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Rev | Author | Line No. | Line |
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96 | giacomo | 1 | |
2 | /* pngwutil.c - utilities to write a PNG file |
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3 | * |
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4 | * libpng 1.2.5 - October 3, 2002 |
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5 | * For conditions of distribution and use, see copyright notice in png.h |
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6 | * Copyright (c) 1998-2002 Glenn Randers-Pehrson |
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7 | * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) |
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8 | * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) |
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9 | */ |
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10 | |||
11 | #define PNG_INTERNAL |
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12 | #include "png.h" |
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13 | #ifdef PNG_WRITE_SUPPORTED |
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14 | |||
15 | /* Place a 32-bit number into a buffer in PNG byte order. We work |
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16 | * with unsigned numbers for convenience, although one supported |
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17 | * ancillary chunk uses signed (two's complement) numbers. |
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18 | */ |
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19 | void /* PRIVATE */ |
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20 | png_save_uint_32(png_bytep buf, png_uint_32 i) |
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21 | { |
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22 | buf[0] = (png_byte)((i >> 24) & 0xff); |
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23 | buf[1] = (png_byte)((i >> 16) & 0xff); |
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24 | buf[2] = (png_byte)((i >> 8) & 0xff); |
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25 | buf[3] = (png_byte)(i & 0xff); |
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26 | } |
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27 | |||
28 | #if defined(PNG_WRITE_pCAL_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED) |
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29 | /* The png_save_int_32 function assumes integers are stored in two's |
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30 | * complement format. If this isn't the case, then this routine needs to |
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31 | * be modified to write data in two's complement format. |
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32 | */ |
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33 | void /* PRIVATE */ |
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34 | png_save_int_32(png_bytep buf, png_int_32 i) |
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35 | { |
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36 | buf[0] = (png_byte)((i >> 24) & 0xff); |
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37 | buf[1] = (png_byte)((i >> 16) & 0xff); |
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38 | buf[2] = (png_byte)((i >> 8) & 0xff); |
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39 | buf[3] = (png_byte)(i & 0xff); |
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40 | } |
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41 | #endif |
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42 | |||
43 | /* Place a 16-bit number into a buffer in PNG byte order. |
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44 | * The parameter is declared unsigned int, not png_uint_16, |
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45 | * just to avoid potential problems on pre-ANSI C compilers. |
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46 | */ |
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47 | void /* PRIVATE */ |
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48 | png_save_uint_16(png_bytep buf, unsigned int i) |
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49 | { |
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50 | buf[0] = (png_byte)((i >> 8) & 0xff); |
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51 | buf[1] = (png_byte)(i & 0xff); |
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52 | } |
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53 | |||
54 | /* Write a PNG chunk all at once. The type is an array of ASCII characters |
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55 | * representing the chunk name. The array must be at least 4 bytes in |
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56 | * length, and does not need to be null terminated. To be safe, pass the |
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57 | * pre-defined chunk names here, and if you need a new one, define it |
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58 | * where the others are defined. The length is the length of the data. |
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59 | * All the data must be present. If that is not possible, use the |
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60 | * png_write_chunk_start(), png_write_chunk_data(), and png_write_chunk_end() |
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61 | * functions instead. |
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62 | */ |
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63 | void PNGAPI |
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64 | png_write_chunk(png_structp png_ptr, png_bytep chunk_name, |
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65 | png_bytep data, png_size_t length) |
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66 | { |
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67 | png_write_chunk_start(png_ptr, chunk_name, (png_uint_32)length); |
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68 | png_write_chunk_data(png_ptr, data, length); |
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69 | png_write_chunk_end(png_ptr); |
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70 | } |
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71 | |||
72 | /* Write the start of a PNG chunk. The type is the chunk type. |
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73 | * The total_length is the sum of the lengths of all the data you will be |
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74 | * passing in png_write_chunk_data(). |
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75 | */ |
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76 | void PNGAPI |
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77 | png_write_chunk_start(png_structp png_ptr, png_bytep chunk_name, |
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78 | png_uint_32 length) |
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79 | { |
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80 | png_byte buf[4]; |
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81 | png_debug2(0, "Writing %s chunk (%lu bytes)\n", chunk_name, length); |
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82 | |||
83 | /* write the length */ |
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84 | png_save_uint_32(buf, length); |
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85 | png_write_data(png_ptr, buf, (png_size_t)4); |
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86 | |||
87 | /* write the chunk name */ |
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88 | png_write_data(png_ptr, chunk_name, (png_size_t)4); |
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89 | /* reset the crc and run it over the chunk name */ |
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90 | png_reset_crc(png_ptr); |
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91 | png_calculate_crc(png_ptr, chunk_name, (png_size_t)4); |
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92 | } |
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93 | |||
94 | /* Write the data of a PNG chunk started with png_write_chunk_start(). |
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95 | * Note that multiple calls to this function are allowed, and that the |
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96 | * sum of the lengths from these calls *must* add up to the total_length |
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97 | * given to png_write_chunk_start(). |
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98 | */ |
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99 | void PNGAPI |
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100 | png_write_chunk_data(png_structp png_ptr, png_bytep data, png_size_t length) |
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101 | { |
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102 | /* write the data, and run the CRC over it */ |
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103 | if (data != NULL && length > 0) |
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104 | { |
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105 | png_calculate_crc(png_ptr, data, length); |
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106 | png_write_data(png_ptr, data, length); |
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107 | } |
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108 | } |
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109 | |||
110 | /* Finish a chunk started with png_write_chunk_start(). */ |
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111 | void PNGAPI |
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112 | png_write_chunk_end(png_structp png_ptr) |
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113 | { |
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114 | png_byte buf[4]; |
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115 | |||
116 | /* write the crc */ |
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117 | png_save_uint_32(buf, png_ptr->crc); |
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118 | |||
119 | png_write_data(png_ptr, buf, (png_size_t)4); |
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120 | } |
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121 | |||
122 | /* Simple function to write the signature. If we have already written |
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123 | * the magic bytes of the signature, or more likely, the PNG stream is |
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124 | * being embedded into another stream and doesn't need its own signature, |
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125 | * we should call png_set_sig_bytes() to tell libpng how many of the |
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126 | * bytes have already been written. |
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127 | */ |
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128 | void /* PRIVATE */ |
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129 | png_write_sig(png_structp png_ptr) |
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130 | { |
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131 | png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10}; |
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132 | /* write the rest of the 8 byte signature */ |
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133 | png_write_data(png_ptr, &png_signature[png_ptr->sig_bytes], |
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134 | (png_size_t)8 - png_ptr->sig_bytes); |
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135 | if(png_ptr->sig_bytes < 3) |
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136 | png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE; |
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137 | } |
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138 | |||
139 | #if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_iCCP_SUPPORTED) |
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140 | /* |
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141 | * This pair of functions encapsulates the operation of (a) compressing a |
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142 | * text string, and (b) issuing it later as a series of chunk data writes. |
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143 | * The compression_state structure is shared context for these functions |
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144 | * set up by the caller in order to make the whole mess thread-safe. |
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145 | */ |
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146 | |||
147 | typedef struct |
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148 | { |
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149 | char *input; /* the uncompressed input data */ |
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150 | int input_len; /* its length */ |
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151 | int num_output_ptr; /* number of output pointers used */ |
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152 | int max_output_ptr; /* size of output_ptr */ |
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153 | png_charpp output_ptr; /* array of pointers to output */ |
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154 | } compression_state; |
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155 | |||
156 | /* compress given text into storage in the png_ptr structure */ |
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157 | static int /* PRIVATE */ |
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158 | png_text_compress(png_structp png_ptr, |
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159 | png_charp text, png_size_t text_len, int compression, |
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160 | compression_state *comp) |
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161 | { |
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162 | int ret; |
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163 | |||
164 | comp->num_output_ptr = comp->max_output_ptr = 0; |
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165 | comp->output_ptr = NULL; |
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166 | comp->input = NULL; |
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167 | |||
168 | /* we may just want to pass the text right through */ |
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169 | if (compression == PNG_TEXT_COMPRESSION_NONE) |
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170 | { |
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171 | comp->input = text; |
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172 | comp->input_len = text_len; |
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173 | return((int)text_len); |
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174 | } |
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175 | |||
176 | if (compression >= PNG_TEXT_COMPRESSION_LAST) |
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177 | { |
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178 | #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE) |
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179 | char msg[50]; |
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180 | sprintf(msg, "Unknown compression type %d", compression); |
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181 | png_warning(png_ptr, msg); |
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182 | #else |
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183 | png_warning(png_ptr, "Unknown compression type"); |
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184 | #endif |
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185 | } |
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186 | |||
187 | /* We can't write the chunk until we find out how much data we have, |
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188 | * which means we need to run the compressor first and save the |
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189 | * output. This shouldn't be a problem, as the vast majority of |
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190 | * comments should be reasonable, but we will set up an array of |
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191 | * malloc'd pointers to be sure. |
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192 | * |
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193 | * If we knew the application was well behaved, we could simplify this |
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194 | * greatly by assuming we can always malloc an output buffer large |
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195 | * enough to hold the compressed text ((1001 * text_len / 1000) + 12) |
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196 | * and malloc this directly. The only time this would be a bad idea is |
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197 | * if we can't malloc more than 64K and we have 64K of random input |
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198 | * data, or if the input string is incredibly large (although this |
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199 | * wouldn't cause a failure, just a slowdown due to swapping). |
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200 | */ |
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201 | |||
202 | /* set up the compression buffers */ |
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203 | png_ptr->zstream.avail_in = (uInt)text_len; |
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204 | png_ptr->zstream.next_in = (Bytef *)text; |
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205 | png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; |
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206 | png_ptr->zstream.next_out = (Bytef *)png_ptr->zbuf; |
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207 | |||
208 | /* this is the same compression loop as in png_write_row() */ |
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209 | do |
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210 | { |
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211 | /* compress the data */ |
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212 | ret = deflate(&png_ptr->zstream, Z_NO_FLUSH); |
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213 | if (ret != Z_OK) |
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214 | { |
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215 | /* error */ |
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216 | if (png_ptr->zstream.msg != NULL) |
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217 | png_error(png_ptr, png_ptr->zstream.msg); |
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218 | else |
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219 | png_error(png_ptr, "zlib error"); |
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220 | } |
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221 | /* check to see if we need more room */ |
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222 | if (!png_ptr->zstream.avail_out && png_ptr->zstream.avail_in) |
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223 | { |
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224 | /* make sure the output array has room */ |
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225 | if (comp->num_output_ptr >= comp->max_output_ptr) |
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226 | { |
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227 | int old_max; |
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228 | |||
229 | old_max = comp->max_output_ptr; |
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230 | comp->max_output_ptr = comp->num_output_ptr + 4; |
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231 | if (comp->output_ptr != NULL) |
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232 | { |
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233 | png_charpp old_ptr; |
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234 | |||
235 | old_ptr = comp->output_ptr; |
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236 | comp->output_ptr = (png_charpp)png_malloc(png_ptr, |
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237 | (png_uint_32)(comp->max_output_ptr * sizeof (png_charpp))); |
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238 | png_memcpy(comp->output_ptr, old_ptr, old_max |
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239 | * sizeof (png_charp)); |
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240 | png_free(png_ptr, old_ptr); |
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241 | } |
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242 | else |
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243 | comp->output_ptr = (png_charpp)png_malloc(png_ptr, |
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244 | (png_uint_32)(comp->max_output_ptr * sizeof (png_charp))); |
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245 | } |
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246 | |||
247 | /* save the data */ |
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248 | comp->output_ptr[comp->num_output_ptr] = (png_charp)png_malloc(png_ptr, |
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249 | (png_uint_32)png_ptr->zbuf_size); |
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250 | png_memcpy(comp->output_ptr[comp->num_output_ptr], png_ptr->zbuf, |
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251 | png_ptr->zbuf_size); |
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252 | comp->num_output_ptr++; |
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253 | |||
254 | /* and reset the buffer */ |
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255 | png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; |
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256 | png_ptr->zstream.next_out = png_ptr->zbuf; |
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257 | } |
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258 | /* continue until we don't have any more to compress */ |
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259 | } while (png_ptr->zstream.avail_in); |
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260 | |||
261 | /* finish the compression */ |
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262 | do |
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263 | { |
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264 | /* tell zlib we are finished */ |
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265 | ret = deflate(&png_ptr->zstream, Z_FINISH); |
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266 | |||
267 | if (ret == Z_OK) |
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268 | { |
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269 | /* check to see if we need more room */ |
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270 | if (!(png_ptr->zstream.avail_out)) |
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271 | { |
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272 | /* check to make sure our output array has room */ |
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273 | if (comp->num_output_ptr >= comp->max_output_ptr) |
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274 | { |
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275 | int old_max; |
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276 | |||
277 | old_max = comp->max_output_ptr; |
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278 | comp->max_output_ptr = comp->num_output_ptr + 4; |
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279 | if (comp->output_ptr != NULL) |
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280 | { |
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281 | png_charpp old_ptr; |
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282 | |||
283 | old_ptr = comp->output_ptr; |
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284 | /* This could be optimized to realloc() */ |
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285 | comp->output_ptr = (png_charpp)png_malloc(png_ptr, |
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286 | (png_uint_32)(comp->max_output_ptr * sizeof (png_charpp))); |
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287 | png_memcpy(comp->output_ptr, old_ptr, |
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288 | old_max * sizeof (png_charp)); |
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289 | png_free(png_ptr, old_ptr); |
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290 | } |
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291 | else |
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292 | comp->output_ptr = (png_charpp)png_malloc(png_ptr, |
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293 | (png_uint_32)(comp->max_output_ptr * sizeof (png_charp))); |
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294 | } |
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295 | |||
296 | /* save off the data */ |
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297 | comp->output_ptr[comp->num_output_ptr] = |
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298 | (png_charp)png_malloc(png_ptr, (png_uint_32)png_ptr->zbuf_size); |
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299 | png_memcpy(comp->output_ptr[comp->num_output_ptr], png_ptr->zbuf, |
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300 | png_ptr->zbuf_size); |
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301 | comp->num_output_ptr++; |
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302 | |||
303 | /* and reset the buffer pointers */ |
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304 | png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; |
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305 | png_ptr->zstream.next_out = png_ptr->zbuf; |
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306 | } |
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307 | } |
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308 | else if (ret != Z_STREAM_END) |
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309 | { |
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310 | /* we got an error */ |
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311 | if (png_ptr->zstream.msg != NULL) |
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312 | png_error(png_ptr, png_ptr->zstream.msg); |
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313 | else |
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314 | png_error(png_ptr, "zlib error"); |
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315 | } |
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316 | } while (ret != Z_STREAM_END); |
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317 | |||
318 | /* text length is number of buffers plus last buffer */ |
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319 | text_len = png_ptr->zbuf_size * comp->num_output_ptr; |
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320 | if (png_ptr->zstream.avail_out < png_ptr->zbuf_size) |
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321 | text_len += png_ptr->zbuf_size - (png_size_t)png_ptr->zstream.avail_out; |
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322 | |||
323 | return((int)text_len); |
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324 | } |
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325 | |||
326 | /* ship the compressed text out via chunk writes */ |
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327 | static void /* PRIVATE */ |
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328 | png_write_compressed_data_out(png_structp png_ptr, compression_state *comp) |
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329 | { |
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330 | int i; |
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331 | |||
332 | /* handle the no-compression case */ |
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333 | if (comp->input) |
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334 | { |
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335 | png_write_chunk_data(png_ptr, (png_bytep)comp->input, |
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336 | (png_size_t)comp->input_len); |
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337 | return; |
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338 | } |
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339 | |||
340 | /* write saved output buffers, if any */ |
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341 | for (i = 0; i < comp->num_output_ptr; i++) |
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342 | { |
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343 | png_write_chunk_data(png_ptr,(png_bytep)comp->output_ptr[i], |
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344 | png_ptr->zbuf_size); |
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345 | png_free(png_ptr, comp->output_ptr[i]); |
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346 | comp->output_ptr[i]=NULL; |
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347 | } |
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348 | if (comp->max_output_ptr != 0) |
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349 | png_free(png_ptr, comp->output_ptr); |
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350 | comp->output_ptr=NULL; |
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351 | /* write anything left in zbuf */ |
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352 | if (png_ptr->zstream.avail_out < (png_uint_32)png_ptr->zbuf_size) |
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353 | png_write_chunk_data(png_ptr, png_ptr->zbuf, |
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354 | png_ptr->zbuf_size - png_ptr->zstream.avail_out); |
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355 | |||
356 | /* reset zlib for another zTXt/iTXt or the image data */ |
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357 | deflateReset(&png_ptr->zstream); |
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358 | |||
359 | } |
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360 | #endif |
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361 | |||
362 | /* Write the IHDR chunk, and update the png_struct with the necessary |
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363 | * information. Note that the rest of this code depends upon this |
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364 | * information being correct. |
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365 | */ |
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366 | void /* PRIVATE */ |
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367 | png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height, |
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368 | int bit_depth, int color_type, int compression_type, int filter_type, |
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369 | int interlace_type) |
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370 | { |
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371 | #ifdef PNG_USE_LOCAL_ARRAYS |
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372 | PNG_IHDR; |
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373 | #endif |
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374 | png_byte buf[13]; /* buffer to store the IHDR info */ |
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375 | |||
376 | png_debug(1, "in png_write_IHDR\n"); |
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377 | /* Check that we have valid input data from the application info */ |
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378 | switch (color_type) |
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379 | { |
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380 | case PNG_COLOR_TYPE_GRAY: |
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381 | switch (bit_depth) |
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382 | { |
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383 | case 1: |
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384 | case 2: |
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385 | case 4: |
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386 | case 8: |
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387 | case 16: png_ptr->channels = 1; break; |
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388 | default: png_error(png_ptr,"Invalid bit depth for grayscale image"); |
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389 | } |
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390 | break; |
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391 | case PNG_COLOR_TYPE_RGB: |
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392 | if (bit_depth != 8 && bit_depth != 16) |
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393 | png_error(png_ptr, "Invalid bit depth for RGB image"); |
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394 | png_ptr->channels = 3; |
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395 | break; |
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396 | case PNG_COLOR_TYPE_PALETTE: |
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397 | switch (bit_depth) |
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398 | { |
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399 | case 1: |
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400 | case 2: |
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401 | case 4: |
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402 | case 8: png_ptr->channels = 1; break; |
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403 | default: png_error(png_ptr, "Invalid bit depth for paletted image"); |
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404 | } |
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405 | break; |
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406 | case PNG_COLOR_TYPE_GRAY_ALPHA: |
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407 | if (bit_depth != 8 && bit_depth != 16) |
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408 | png_error(png_ptr, "Invalid bit depth for grayscale+alpha image"); |
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409 | png_ptr->channels = 2; |
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410 | break; |
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411 | case PNG_COLOR_TYPE_RGB_ALPHA: |
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412 | if (bit_depth != 8 && bit_depth != 16) |
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413 | png_error(png_ptr, "Invalid bit depth for RGBA image"); |
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414 | png_ptr->channels = 4; |
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415 | break; |
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416 | default: |
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417 | png_error(png_ptr, "Invalid image color type specified"); |
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418 | } |
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419 | |||
420 | if (compression_type != PNG_COMPRESSION_TYPE_BASE) |
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421 | { |
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422 | png_warning(png_ptr, "Invalid compression type specified"); |
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423 | compression_type = PNG_COMPRESSION_TYPE_BASE; |
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424 | } |
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425 | |||
426 | /* Write filter_method 64 (intrapixel differencing) only if |
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427 | * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and |
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428 | * 2. Libpng did not write a PNG signature (this filter_method is only |
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429 | * used in PNG datastreams that are embedded in MNG datastreams) and |
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430 | * 3. The application called png_permit_mng_features with a mask that |
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431 | * included PNG_FLAG_MNG_FILTER_64 and |
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432 | * 4. The filter_method is 64 and |
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433 | * 5. The color_type is RGB or RGBA |
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434 | */ |
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435 | if ( |
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436 | #if defined(PNG_MNG_FEATURES_SUPPORTED) |
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437 | !((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) && |
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438 | ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) == 0) && |
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439 | (color_type == PNG_COLOR_TYPE_RGB || |
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440 | color_type == PNG_COLOR_TYPE_RGB_ALPHA) && |
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441 | (filter_type == PNG_INTRAPIXEL_DIFFERENCING)) && |
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442 | #endif |
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443 | filter_type != PNG_FILTER_TYPE_BASE) |
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444 | { |
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445 | png_warning(png_ptr, "Invalid filter type specified"); |
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446 | filter_type = PNG_FILTER_TYPE_BASE; |
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447 | } |
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448 | |||
449 | #ifdef PNG_WRITE_INTERLACING_SUPPORTED |
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450 | if (interlace_type != PNG_INTERLACE_NONE && |
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451 | interlace_type != PNG_INTERLACE_ADAM7) |
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452 | { |
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453 | png_warning(png_ptr, "Invalid interlace type specified"); |
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454 | interlace_type = PNG_INTERLACE_ADAM7; |
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455 | } |
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456 | #else |
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457 | interlace_type=PNG_INTERLACE_NONE; |
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458 | #endif |
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459 | |||
460 | /* save off the relevent information */ |
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461 | png_ptr->bit_depth = (png_byte)bit_depth; |
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462 | png_ptr->color_type = (png_byte)color_type; |
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463 | png_ptr->interlaced = (png_byte)interlace_type; |
||
464 | #if defined(PNG_MNG_FEATURES_SUPPORTED) |
||
465 | png_ptr->filter_type = (png_byte)filter_type; |
||
466 | #endif |
||
467 | png_ptr->width = width; |
||
468 | png_ptr->height = height; |
||
469 | |||
470 | png_ptr->pixel_depth = (png_byte)(bit_depth * png_ptr->channels); |
||
471 | png_ptr->rowbytes = ((width * (png_size_t)png_ptr->pixel_depth + 7) >> 3); |
||
472 | /* set the usr info, so any transformations can modify it */ |
||
473 | png_ptr->usr_width = png_ptr->width; |
||
474 | png_ptr->usr_bit_depth = png_ptr->bit_depth; |
||
475 | png_ptr->usr_channels = png_ptr->channels; |
||
476 | |||
477 | /* pack the header information into the buffer */ |
||
478 | png_save_uint_32(buf, width); |
||
479 | png_save_uint_32(buf + 4, height); |
||
480 | buf[8] = (png_byte)bit_depth; |
||
481 | buf[9] = (png_byte)color_type; |
||
482 | buf[10] = (png_byte)compression_type; |
||
483 | buf[11] = (png_byte)filter_type; |
||
484 | buf[12] = (png_byte)interlace_type; |
||
485 | |||
486 | /* write the chunk */ |
||
487 | png_write_chunk(png_ptr, (png_bytep)png_IHDR, buf, (png_size_t)13); |
||
488 | |||
489 | /* initialize zlib with PNG info */ |
||
490 | png_ptr->zstream.zalloc = png_zalloc; |
||
491 | png_ptr->zstream.zfree = png_zfree; |
||
492 | png_ptr->zstream.opaque = (voidpf)png_ptr; |
||
493 | if (!(png_ptr->do_filter)) |
||
494 | { |
||
495 | if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE || |
||
496 | png_ptr->bit_depth < 8) |
||
497 | png_ptr->do_filter = PNG_FILTER_NONE; |
||
498 | else |
||
499 | png_ptr->do_filter = PNG_ALL_FILTERS; |
||
500 | } |
||
501 | if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_STRATEGY)) |
||
502 | { |
||
503 | if (png_ptr->do_filter != PNG_FILTER_NONE) |
||
504 | png_ptr->zlib_strategy = Z_FILTERED; |
||
505 | else |
||
506 | png_ptr->zlib_strategy = Z_DEFAULT_STRATEGY; |
||
507 | } |
||
508 | if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_LEVEL)) |
||
509 | png_ptr->zlib_level = Z_DEFAULT_COMPRESSION; |
||
510 | if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL)) |
||
511 | png_ptr->zlib_mem_level = 8; |
||
512 | if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS)) |
||
513 | png_ptr->zlib_window_bits = 15; |
||
514 | if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_METHOD)) |
||
515 | png_ptr->zlib_method = 8; |
||
516 | deflateInit2(&png_ptr->zstream, png_ptr->zlib_level, |
||
517 | png_ptr->zlib_method, png_ptr->zlib_window_bits, |
||
518 | png_ptr->zlib_mem_level, png_ptr->zlib_strategy); |
||
519 | png_ptr->zstream.next_out = png_ptr->zbuf; |
||
520 | png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; |
||
521 | |||
522 | png_ptr->mode = PNG_HAVE_IHDR; |
||
523 | } |
||
524 | |||
525 | /* write the palette. We are careful not to trust png_color to be in the |
||
526 | * correct order for PNG, so people can redefine it to any convenient |
||
527 | * structure. |
||
528 | */ |
||
529 | void /* PRIVATE */ |
||
530 | png_write_PLTE(png_structp png_ptr, png_colorp palette, png_uint_32 num_pal) |
||
531 | { |
||
532 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
533 | PNG_PLTE; |
||
534 | #endif |
||
535 | png_uint_32 i; |
||
536 | png_colorp pal_ptr; |
||
537 | png_byte buf[3]; |
||
538 | |||
539 | png_debug(1, "in png_write_PLTE\n"); |
||
540 | if (( |
||
541 | #if defined(PNG_MNG_FEATURES_SUPPORTED) |
||
542 | !(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) && |
||
543 | #endif |
||
544 | num_pal == 0) || num_pal > 256) |
||
545 | { |
||
546 | if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
||
547 | { |
||
548 | png_error(png_ptr, "Invalid number of colors in palette"); |
||
549 | } |
||
550 | else |
||
551 | { |
||
552 | png_warning(png_ptr, "Invalid number of colors in palette"); |
||
553 | return; |
||
554 | } |
||
555 | } |
||
556 | |||
557 | if (!(png_ptr->color_type&PNG_COLOR_MASK_COLOR)) |
||
558 | { |
||
559 | png_warning(png_ptr, |
||
560 | "Ignoring request to write a PLTE chunk in grayscale PNG"); |
||
561 | return; |
||
562 | } |
||
563 | |||
564 | png_ptr->num_palette = (png_uint_16)num_pal; |
||
565 | png_debug1(3, "num_palette = %d\n", png_ptr->num_palette); |
||
566 | |||
567 | png_write_chunk_start(png_ptr, (png_bytep)png_PLTE, num_pal * 3); |
||
568 | #ifndef PNG_NO_POINTER_INDEXING |
||
569 | for (i = 0, pal_ptr = palette; i < num_pal; i++, pal_ptr++) |
||
570 | { |
||
571 | buf[0] = pal_ptr->red; |
||
572 | buf[1] = pal_ptr->green; |
||
573 | buf[2] = pal_ptr->blue; |
||
574 | png_write_chunk_data(png_ptr, buf, (png_size_t)3); |
||
575 | } |
||
576 | #else |
||
577 | /* This is a little slower but some buggy compilers need to do this instead */ |
||
578 | pal_ptr=palette; |
||
579 | for (i = 0; i < num_pal; i++) |
||
580 | { |
||
581 | buf[0] = pal_ptr[i].red; |
||
582 | buf[1] = pal_ptr[i].green; |
||
583 | buf[2] = pal_ptr[i].blue; |
||
584 | png_write_chunk_data(png_ptr, buf, (png_size_t)3); |
||
585 | } |
||
586 | #endif |
||
587 | png_write_chunk_end(png_ptr); |
||
588 | png_ptr->mode |= PNG_HAVE_PLTE; |
||
589 | } |
||
590 | |||
591 | /* write an IDAT chunk */ |
||
592 | void /* PRIVATE */ |
||
593 | png_write_IDAT(png_structp png_ptr, png_bytep data, png_size_t length) |
||
594 | { |
||
595 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
596 | PNG_IDAT; |
||
597 | #endif |
||
598 | png_debug(1, "in png_write_IDAT\n"); |
||
599 | png_write_chunk(png_ptr, (png_bytep)png_IDAT, data, length); |
||
600 | png_ptr->mode |= PNG_HAVE_IDAT; |
||
601 | } |
||
602 | |||
603 | /* write an IEND chunk */ |
||
604 | void /* PRIVATE */ |
||
605 | png_write_IEND(png_structp png_ptr) |
||
606 | { |
||
607 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
608 | PNG_IEND; |
||
609 | #endif |
||
610 | png_debug(1, "in png_write_IEND\n"); |
||
611 | png_write_chunk(png_ptr, (png_bytep)png_IEND, png_bytep_NULL, |
||
612 | (png_size_t)0); |
||
613 | png_ptr->mode |= PNG_HAVE_IEND; |
||
614 | } |
||
615 | |||
616 | #if defined(PNG_WRITE_gAMA_SUPPORTED) |
||
617 | /* write a gAMA chunk */ |
||
618 | #ifdef PNG_FLOATING_POINT_SUPPORTED |
||
619 | void /* PRIVATE */ |
||
620 | png_write_gAMA(png_structp png_ptr, double file_gamma) |
||
621 | { |
||
622 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
623 | PNG_gAMA; |
||
624 | #endif |
||
625 | png_uint_32 igamma; |
||
626 | png_byte buf[4]; |
||
627 | |||
628 | png_debug(1, "in png_write_gAMA\n"); |
||
629 | /* file_gamma is saved in 1/100,000ths */ |
||
630 | igamma = (png_uint_32)(file_gamma * 100000.0 + 0.5); |
||
631 | png_save_uint_32(buf, igamma); |
||
632 | png_write_chunk(png_ptr, (png_bytep)png_gAMA, buf, (png_size_t)4); |
||
633 | } |
||
634 | #endif |
||
635 | #ifdef PNG_FIXED_POINT_SUPPORTED |
||
636 | void /* PRIVATE */ |
||
637 | png_write_gAMA_fixed(png_structp png_ptr, png_fixed_point file_gamma) |
||
638 | { |
||
639 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
640 | PNG_gAMA; |
||
641 | #endif |
||
642 | png_byte buf[4]; |
||
643 | |||
644 | png_debug(1, "in png_write_gAMA\n"); |
||
645 | /* file_gamma is saved in 1/100,000ths */ |
||
646 | png_save_uint_32(buf, (png_uint_32)file_gamma); |
||
647 | png_write_chunk(png_ptr, (png_bytep)png_gAMA, buf, (png_size_t)4); |
||
648 | } |
||
649 | #endif |
||
650 | #endif |
||
651 | |||
652 | #if defined(PNG_WRITE_sRGB_SUPPORTED) |
||
653 | /* write a sRGB chunk */ |
||
654 | void /* PRIVATE */ |
||
655 | png_write_sRGB(png_structp png_ptr, int srgb_intent) |
||
656 | { |
||
657 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
658 | PNG_sRGB; |
||
659 | #endif |
||
660 | png_byte buf[1]; |
||
661 | |||
662 | png_debug(1, "in png_write_sRGB\n"); |
||
663 | if(srgb_intent >= PNG_sRGB_INTENT_LAST) |
||
664 | png_warning(png_ptr, |
||
665 | "Invalid sRGB rendering intent specified"); |
||
666 | buf[0]=(png_byte)srgb_intent; |
||
667 | png_write_chunk(png_ptr, (png_bytep)png_sRGB, buf, (png_size_t)1); |
||
668 | } |
||
669 | #endif |
||
670 | |||
671 | #if defined(PNG_WRITE_iCCP_SUPPORTED) |
||
672 | /* write an iCCP chunk */ |
||
673 | void /* PRIVATE */ |
||
674 | png_write_iCCP(png_structp png_ptr, png_charp name, int compression_type, |
||
675 | png_charp profile, int profile_len) |
||
676 | { |
||
677 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
678 | PNG_iCCP; |
||
679 | #endif |
||
680 | png_size_t name_len; |
||
681 | png_charp new_name; |
||
682 | compression_state comp; |
||
683 | |||
684 | png_debug(1, "in png_write_iCCP\n"); |
||
685 | if (name == NULL || (name_len = png_check_keyword(png_ptr, name, |
||
686 | &new_name)) == 0) |
||
687 | { |
||
688 | png_warning(png_ptr, "Empty keyword in iCCP chunk"); |
||
689 | return; |
||
690 | } |
||
691 | |||
692 | if (compression_type != PNG_COMPRESSION_TYPE_BASE) |
||
693 | png_warning(png_ptr, "Unknown compression type in iCCP chunk"); |
||
694 | |||
695 | if (profile == NULL) |
||
696 | profile_len = 0; |
||
697 | |||
698 | if (profile_len) |
||
699 | profile_len = png_text_compress(png_ptr, profile, (png_size_t)profile_len, |
||
700 | PNG_COMPRESSION_TYPE_BASE, &comp); |
||
701 | |||
702 | /* make sure we include the NULL after the name and the compression type */ |
||
703 | png_write_chunk_start(png_ptr, (png_bytep)png_iCCP, |
||
704 | (png_uint_32)name_len+profile_len+2); |
||
705 | new_name[name_len+1]=0x00; |
||
706 | png_write_chunk_data(png_ptr, (png_bytep)new_name, name_len + 2); |
||
707 | |||
708 | if (profile_len) |
||
709 | png_write_compressed_data_out(png_ptr, &comp); |
||
710 | |||
711 | png_write_chunk_end(png_ptr); |
||
712 | png_free(png_ptr, new_name); |
||
713 | } |
||
714 | #endif |
||
715 | |||
716 | #if defined(PNG_WRITE_sPLT_SUPPORTED) |
||
717 | /* write a sPLT chunk */ |
||
718 | void /* PRIVATE */ |
||
719 | png_write_sPLT(png_structp png_ptr, png_sPLT_tp spalette) |
||
720 | { |
||
721 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
722 | PNG_sPLT; |
||
723 | #endif |
||
724 | png_size_t name_len; |
||
725 | png_charp new_name; |
||
726 | png_byte entrybuf[10]; |
||
727 | int entry_size = (spalette->depth == 8 ? 6 : 10); |
||
728 | int palette_size = entry_size * spalette->nentries; |
||
729 | png_sPLT_entryp ep; |
||
730 | #ifdef PNG_NO_POINTER_INDEXING |
||
731 | int i; |
||
732 | #endif |
||
733 | |||
734 | png_debug(1, "in png_write_sPLT\n"); |
||
735 | if (spalette->name == NULL || (name_len = png_check_keyword(png_ptr, |
||
736 | spalette->name, &new_name))==0) |
||
737 | { |
||
738 | png_warning(png_ptr, "Empty keyword in sPLT chunk"); |
||
739 | return; |
||
740 | } |
||
741 | |||
742 | /* make sure we include the NULL after the name */ |
||
743 | png_write_chunk_start(png_ptr, (png_bytep)png_sPLT, |
||
744 | (png_uint_32)(name_len + 2 + palette_size)); |
||
745 | png_write_chunk_data(png_ptr, (png_bytep)new_name, name_len + 1); |
||
746 | png_write_chunk_data(png_ptr, (png_bytep)&spalette->depth, 1); |
||
747 | |||
748 | /* loop through each palette entry, writing appropriately */ |
||
749 | #ifndef PNG_NO_POINTER_INDEXING |
||
750 | for (ep = spalette->entries; ep<spalette->entries+spalette->nentries; ep++) |
||
751 | { |
||
752 | if (spalette->depth == 8) |
||
753 | { |
||
754 | entrybuf[0] = (png_byte)ep->red; |
||
755 | entrybuf[1] = (png_byte)ep->green; |
||
756 | entrybuf[2] = (png_byte)ep->blue; |
||
757 | entrybuf[3] = (png_byte)ep->alpha; |
||
758 | png_save_uint_16(entrybuf + 4, ep->frequency); |
||
759 | } |
||
760 | else |
||
761 | { |
||
762 | png_save_uint_16(entrybuf + 0, ep->red); |
||
763 | png_save_uint_16(entrybuf + 2, ep->green); |
||
764 | png_save_uint_16(entrybuf + 4, ep->blue); |
||
765 | png_save_uint_16(entrybuf + 6, ep->alpha); |
||
766 | png_save_uint_16(entrybuf + 8, ep->frequency); |
||
767 | } |
||
768 | png_write_chunk_data(png_ptr, entrybuf, (png_size_t)entry_size); |
||
769 | } |
||
770 | #else |
||
771 | ep=spalette->entries; |
||
772 | for (i=0; i>spalette->nentries; i++) |
||
773 | { |
||
774 | if (spalette->depth == 8) |
||
775 | { |
||
776 | entrybuf[0] = (png_byte)ep[i].red; |
||
777 | entrybuf[1] = (png_byte)ep[i].green; |
||
778 | entrybuf[2] = (png_byte)ep[i].blue; |
||
779 | entrybuf[3] = (png_byte)ep[i].alpha; |
||
780 | png_save_uint_16(entrybuf + 4, ep[i].frequency); |
||
781 | } |
||
782 | else |
||
783 | { |
||
784 | png_save_uint_16(entrybuf + 0, ep[i].red); |
||
785 | png_save_uint_16(entrybuf + 2, ep[i].green); |
||
786 | png_save_uint_16(entrybuf + 4, ep[i].blue); |
||
787 | png_save_uint_16(entrybuf + 6, ep[i].alpha); |
||
788 | png_save_uint_16(entrybuf + 8, ep[i].frequency); |
||
789 | } |
||
790 | png_write_chunk_data(png_ptr, entrybuf, entry_size); |
||
791 | } |
||
792 | #endif |
||
793 | |||
794 | png_write_chunk_end(png_ptr); |
||
795 | png_free(png_ptr, new_name); |
||
796 | } |
||
797 | #endif |
||
798 | |||
799 | #if defined(PNG_WRITE_sBIT_SUPPORTED) |
||
800 | /* write the sBIT chunk */ |
||
801 | void /* PRIVATE */ |
||
802 | png_write_sBIT(png_structp png_ptr, png_color_8p sbit, int color_type) |
||
803 | { |
||
804 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
805 | PNG_sBIT; |
||
806 | #endif |
||
807 | png_byte buf[4]; |
||
808 | png_size_t size; |
||
809 | |||
810 | png_debug(1, "in png_write_sBIT\n"); |
||
811 | /* make sure we don't depend upon the order of PNG_COLOR_8 */ |
||
812 | if (color_type & PNG_COLOR_MASK_COLOR) |
||
813 | { |
||
814 | png_byte maxbits; |
||
815 | |||
816 | maxbits = (png_byte)(color_type==PNG_COLOR_TYPE_PALETTE ? 8 : |
||
817 | png_ptr->usr_bit_depth); |
||
818 | if (sbit->red == 0 || sbit->red > maxbits || |
||
819 | sbit->green == 0 || sbit->green > maxbits || |
||
820 | sbit->blue == 0 || sbit->blue > maxbits) |
||
821 | { |
||
822 | png_warning(png_ptr, "Invalid sBIT depth specified"); |
||
823 | return; |
||
824 | } |
||
825 | buf[0] = sbit->red; |
||
826 | buf[1] = sbit->green; |
||
827 | buf[2] = sbit->blue; |
||
828 | size = 3; |
||
829 | } |
||
830 | else |
||
831 | { |
||
832 | if (sbit->gray == 0 || sbit->gray > png_ptr->usr_bit_depth) |
||
833 | { |
||
834 | png_warning(png_ptr, "Invalid sBIT depth specified"); |
||
835 | return; |
||
836 | } |
||
837 | buf[0] = sbit->gray; |
||
838 | size = 1; |
||
839 | } |
||
840 | |||
841 | if (color_type & PNG_COLOR_MASK_ALPHA) |
||
842 | { |
||
843 | if (sbit->alpha == 0 || sbit->alpha > png_ptr->usr_bit_depth) |
||
844 | { |
||
845 | png_warning(png_ptr, "Invalid sBIT depth specified"); |
||
846 | return; |
||
847 | } |
||
848 | buf[size++] = sbit->alpha; |
||
849 | } |
||
850 | |||
851 | png_write_chunk(png_ptr, (png_bytep)png_sBIT, buf, size); |
||
852 | } |
||
853 | #endif |
||
854 | |||
855 | #if defined(PNG_WRITE_cHRM_SUPPORTED) |
||
856 | /* write the cHRM chunk */ |
||
857 | #ifdef PNG_FLOATING_POINT_SUPPORTED |
||
858 | void /* PRIVATE */ |
||
859 | png_write_cHRM(png_structp png_ptr, double white_x, double white_y, |
||
860 | double red_x, double red_y, double green_x, double green_y, |
||
861 | double blue_x, double blue_y) |
||
862 | { |
||
863 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
864 | PNG_cHRM; |
||
865 | #endif |
||
866 | png_byte buf[32]; |
||
867 | png_uint_32 itemp; |
||
868 | |||
869 | png_debug(1, "in png_write_cHRM\n"); |
||
870 | /* each value is saved in 1/100,000ths */ |
||
871 | if (white_x < 0 || white_x > 0.8 || white_y < 0 || white_y > 0.8 || |
||
872 | white_x + white_y > 1.0) |
||
873 | { |
||
874 | png_warning(png_ptr, "Invalid cHRM white point specified"); |
||
875 | #if !defined(PNG_NO_CONSOLE_IO) |
||
876 | cprintf("white_x=%f, white_y=%f\n",white_x, white_y); |
||
877 | #endif |
||
878 | return; |
||
879 | } |
||
880 | itemp = (png_uint_32)(white_x * 100000.0 + 0.5); |
||
881 | png_save_uint_32(buf, itemp); |
||
882 | itemp = (png_uint_32)(white_y * 100000.0 + 0.5); |
||
883 | png_save_uint_32(buf + 4, itemp); |
||
884 | |||
885 | if (red_x < 0 || red_x > 0.8 || red_y < 0 || red_y > 0.8 || |
||
886 | red_x + red_y > 1.0) |
||
887 | { |
||
888 | png_warning(png_ptr, "Invalid cHRM red point specified"); |
||
889 | return; |
||
890 | } |
||
891 | itemp = (png_uint_32)(red_x * 100000.0 + 0.5); |
||
892 | png_save_uint_32(buf + 8, itemp); |
||
893 | itemp = (png_uint_32)(red_y * 100000.0 + 0.5); |
||
894 | png_save_uint_32(buf + 12, itemp); |
||
895 | |||
896 | if (green_x < 0 || green_x > 0.8 || green_y < 0 || green_y > 0.8 || |
||
897 | green_x + green_y > 1.0) |
||
898 | { |
||
899 | png_warning(png_ptr, "Invalid cHRM green point specified"); |
||
900 | return; |
||
901 | } |
||
902 | itemp = (png_uint_32)(green_x * 100000.0 + 0.5); |
||
903 | png_save_uint_32(buf + 16, itemp); |
||
904 | itemp = (png_uint_32)(green_y * 100000.0 + 0.5); |
||
905 | png_save_uint_32(buf + 20, itemp); |
||
906 | |||
907 | if (blue_x < 0 || blue_x > 0.8 || blue_y < 0 || blue_y > 0.8 || |
||
908 | blue_x + blue_y > 1.0) |
||
909 | { |
||
910 | png_warning(png_ptr, "Invalid cHRM blue point specified"); |
||
911 | return; |
||
912 | } |
||
913 | itemp = (png_uint_32)(blue_x * 100000.0 + 0.5); |
||
914 | png_save_uint_32(buf + 24, itemp); |
||
915 | itemp = (png_uint_32)(blue_y * 100000.0 + 0.5); |
||
916 | png_save_uint_32(buf + 28, itemp); |
||
917 | |||
918 | png_write_chunk(png_ptr, (png_bytep)png_cHRM, buf, (png_size_t)32); |
||
919 | } |
||
920 | #endif |
||
921 | #ifdef PNG_FIXED_POINT_SUPPORTED |
||
922 | void /* PRIVATE */ |
||
923 | png_write_cHRM_fixed(png_structp png_ptr, png_fixed_point white_x, |
||
924 | png_fixed_point white_y, png_fixed_point red_x, png_fixed_point red_y, |
||
925 | png_fixed_point green_x, png_fixed_point green_y, png_fixed_point blue_x, |
||
926 | png_fixed_point blue_y) |
||
927 | { |
||
928 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
929 | PNG_cHRM; |
||
930 | #endif |
||
931 | png_byte buf[32]; |
||
932 | |||
933 | png_debug(1, "in png_write_cHRM\n"); |
||
934 | /* each value is saved in 1/100,000ths */ |
||
935 | if (white_x > 80000L || white_y > 80000L || white_x + white_y > 100000L) |
||
936 | { |
||
937 | png_warning(png_ptr, "Invalid fixed cHRM white point specified"); |
||
938 | #if !defined(PNG_NO_CONSOLE_IO) |
||
939 | cprintf("white_x=%ld, white_y=%ld\n",white_x, white_y); |
||
940 | #endif |
||
941 | return; |
||
942 | } |
||
943 | png_save_uint_32(buf, (png_uint_32)white_x); |
||
944 | png_save_uint_32(buf + 4, (png_uint_32)white_y); |
||
945 | |||
946 | if (red_x > 80000L || red_y > 80000L || red_x + red_y > 100000L) |
||
947 | { |
||
948 | png_warning(png_ptr, "Invalid cHRM fixed red point specified"); |
||
949 | return; |
||
950 | } |
||
951 | png_save_uint_32(buf + 8, (png_uint_32)red_x); |
||
952 | png_save_uint_32(buf + 12, (png_uint_32)red_y); |
||
953 | |||
954 | if (green_x > 80000L || green_y > 80000L || green_x + green_y > 100000L) |
||
955 | { |
||
956 | png_warning(png_ptr, "Invalid fixed cHRM green point specified"); |
||
957 | return; |
||
958 | } |
||
959 | png_save_uint_32(buf + 16, (png_uint_32)green_x); |
||
960 | png_save_uint_32(buf + 20, (png_uint_32)green_y); |
||
961 | |||
962 | if (blue_x > 80000L || blue_y > 80000L || blue_x + blue_y > 100000L) |
||
963 | { |
||
964 | png_warning(png_ptr, "Invalid fixed cHRM blue point specified"); |
||
965 | return; |
||
966 | } |
||
967 | png_save_uint_32(buf + 24, (png_uint_32)blue_x); |
||
968 | png_save_uint_32(buf + 28, (png_uint_32)blue_y); |
||
969 | |||
970 | png_write_chunk(png_ptr, (png_bytep)png_cHRM, buf, (png_size_t)32); |
||
971 | } |
||
972 | #endif |
||
973 | #endif |
||
974 | |||
975 | #if defined(PNG_WRITE_tRNS_SUPPORTED) |
||
976 | /* write the tRNS chunk */ |
||
977 | void /* PRIVATE */ |
||
978 | png_write_tRNS(png_structp png_ptr, png_bytep trans, png_color_16p tran, |
||
979 | int num_trans, int color_type) |
||
980 | { |
||
981 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
982 | PNG_tRNS; |
||
983 | #endif |
||
984 | png_byte buf[6]; |
||
985 | |||
986 | png_debug(1, "in png_write_tRNS\n"); |
||
987 | if (color_type == PNG_COLOR_TYPE_PALETTE) |
||
988 | { |
||
989 | if (num_trans <= 0 || num_trans > (int)png_ptr->num_palette) |
||
990 | { |
||
991 | png_warning(png_ptr,"Invalid number of transparent colors specified"); |
||
992 | return; |
||
993 | } |
||
994 | /* write the chunk out as it is */ |
||
995 | png_write_chunk(png_ptr, (png_bytep)png_tRNS, trans, (png_size_t)num_trans); |
||
996 | } |
||
997 | else if (color_type == PNG_COLOR_TYPE_GRAY) |
||
998 | { |
||
999 | /* one 16 bit value */ |
||
1000 | if(tran->gray >= (1 << png_ptr->bit_depth)) |
||
1001 | { |
||
1002 | png_warning(png_ptr, |
||
1003 | "Ignoring attempt to write tRNS chunk out-of-range for bit_depth"); |
||
1004 | return; |
||
1005 | } |
||
1006 | png_save_uint_16(buf, tran->gray); |
||
1007 | png_write_chunk(png_ptr, (png_bytep)png_tRNS, buf, (png_size_t)2); |
||
1008 | } |
||
1009 | else if (color_type == PNG_COLOR_TYPE_RGB) |
||
1010 | { |
||
1011 | /* three 16 bit values */ |
||
1012 | png_save_uint_16(buf, tran->red); |
||
1013 | png_save_uint_16(buf + 2, tran->green); |
||
1014 | png_save_uint_16(buf + 4, tran->blue); |
||
1015 | if(png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4])) |
||
1016 | { |
||
1017 | png_warning(png_ptr, |
||
1018 | "Ignoring attempt to write 16-bit tRNS chunk when bit_depth is 8"); |
||
1019 | return; |
||
1020 | } |
||
1021 | png_write_chunk(png_ptr, (png_bytep)png_tRNS, buf, (png_size_t)6); |
||
1022 | } |
||
1023 | else |
||
1024 | { |
||
1025 | png_warning(png_ptr, "Can't write tRNS with an alpha channel"); |
||
1026 | } |
||
1027 | } |
||
1028 | #endif |
||
1029 | |||
1030 | #if defined(PNG_WRITE_bKGD_SUPPORTED) |
||
1031 | /* write the background chunk */ |
||
1032 | void /* PRIVATE */ |
||
1033 | png_write_bKGD(png_structp png_ptr, png_color_16p back, int color_type) |
||
1034 | { |
||
1035 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
1036 | PNG_bKGD; |
||
1037 | #endif |
||
1038 | png_byte buf[6]; |
||
1039 | |||
1040 | png_debug(1, "in png_write_bKGD\n"); |
||
1041 | if (color_type == PNG_COLOR_TYPE_PALETTE) |
||
1042 | { |
||
1043 | if ( |
||
1044 | #if defined(PNG_MNG_FEATURES_SUPPORTED) |
||
1045 | (png_ptr->num_palette || |
||
1046 | (!(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE))) && |
||
1047 | #endif |
||
1048 | back->index > png_ptr->num_palette) |
||
1049 | { |
||
1050 | png_warning(png_ptr, "Invalid background palette index"); |
||
1051 | return; |
||
1052 | } |
||
1053 | buf[0] = back->index; |
||
1054 | png_write_chunk(png_ptr, (png_bytep)png_bKGD, buf, (png_size_t)1); |
||
1055 | } |
||
1056 | else if (color_type & PNG_COLOR_MASK_COLOR) |
||
1057 | { |
||
1058 | png_save_uint_16(buf, back->red); |
||
1059 | png_save_uint_16(buf + 2, back->green); |
||
1060 | png_save_uint_16(buf + 4, back->blue); |
||
1061 | if(png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4])) |
||
1062 | { |
||
1063 | png_warning(png_ptr, |
||
1064 | "Ignoring attempt to write 16-bit bKGD chunk when bit_depth is 8"); |
||
1065 | return; |
||
1066 | } |
||
1067 | png_write_chunk(png_ptr, (png_bytep)png_bKGD, buf, (png_size_t)6); |
||
1068 | } |
||
1069 | else |
||
1070 | { |
||
1071 | if(back->gray >= (1 << png_ptr->bit_depth)) |
||
1072 | { |
||
1073 | png_warning(png_ptr, |
||
1074 | "Ignoring attempt to write bKGD chunk out-of-range for bit_depth"); |
||
1075 | return; |
||
1076 | } |
||
1077 | png_save_uint_16(buf, back->gray); |
||
1078 | png_write_chunk(png_ptr, (png_bytep)png_bKGD, buf, (png_size_t)2); |
||
1079 | } |
||
1080 | } |
||
1081 | #endif |
||
1082 | |||
1083 | #if defined(PNG_WRITE_hIST_SUPPORTED) |
||
1084 | /* write the histogram */ |
||
1085 | void /* PRIVATE */ |
||
1086 | png_write_hIST(png_structp png_ptr, png_uint_16p hist, int num_hist) |
||
1087 | { |
||
1088 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
1089 | PNG_hIST; |
||
1090 | #endif |
||
1091 | int i; |
||
1092 | png_byte buf[3]; |
||
1093 | |||
1094 | png_debug(1, "in png_write_hIST\n"); |
||
1095 | if (num_hist > (int)png_ptr->num_palette) |
||
1096 | { |
||
1097 | png_debug2(3, "num_hist = %d, num_palette = %d\n", num_hist, |
||
1098 | png_ptr->num_palette); |
||
1099 | png_warning(png_ptr, "Invalid number of histogram entries specified"); |
||
1100 | return; |
||
1101 | } |
||
1102 | |||
1103 | png_write_chunk_start(png_ptr, (png_bytep)png_hIST, (png_uint_32)(num_hist * 2)); |
||
1104 | for (i = 0; i < num_hist; i++) |
||
1105 | { |
||
1106 | png_save_uint_16(buf, hist[i]); |
||
1107 | png_write_chunk_data(png_ptr, buf, (png_size_t)2); |
||
1108 | } |
||
1109 | png_write_chunk_end(png_ptr); |
||
1110 | } |
||
1111 | #endif |
||
1112 | |||
1113 | #if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \ |
||
1114 | defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED) |
||
1115 | /* Check that the tEXt or zTXt keyword is valid per PNG 1.0 specification, |
||
1116 | * and if invalid, correct the keyword rather than discarding the entire |
||
1117 | * chunk. The PNG 1.0 specification requires keywords 1-79 characters in |
||
1118 | * length, forbids leading or trailing whitespace, multiple internal spaces, |
||
1119 | * and the non-break space (0x80) from ISO 8859-1. Returns keyword length. |
||
1120 | * |
||
1121 | * The new_key is allocated to hold the corrected keyword and must be freed |
||
1122 | * by the calling routine. This avoids problems with trying to write to |
||
1123 | * static keywords without having to have duplicate copies of the strings. |
||
1124 | */ |
||
1125 | png_size_t /* PRIVATE */ |
||
1126 | png_check_keyword(png_structp png_ptr, png_charp key, png_charpp new_key) |
||
1127 | { |
||
1128 | png_size_t key_len; |
||
1129 | png_charp kp, dp; |
||
1130 | int kflag; |
||
1131 | int kwarn=0; |
||
1132 | |||
1133 | png_debug(1, "in png_check_keyword\n"); |
||
1134 | *new_key = NULL; |
||
1135 | |||
1136 | if (key == NULL || (key_len = png_strlen(key)) == 0) |
||
1137 | { |
||
1138 | png_warning(png_ptr, "zero length keyword"); |
||
1139 | return ((png_size_t)0); |
||
1140 | } |
||
1141 | |||
1142 | png_debug1(2, "Keyword to be checked is '%s'\n", key); |
||
1143 | |||
1144 | *new_key = (png_charp)png_malloc(png_ptr, (png_uint_32)(key_len + 2)); |
||
1145 | |||
1146 | /* Replace non-printing characters with a blank and print a warning */ |
||
1147 | for (kp = key, dp = *new_key; *kp != '\0'; kp++, dp++) |
||
1148 | { |
||
1149 | if (*kp < 0x20 || (*kp > 0x7E && (png_byte)*kp < 0xA1)) |
||
1150 | { |
||
1151 | #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE) |
||
1152 | char msg[40]; |
||
1153 | |||
1154 | sprintf(msg, "invalid keyword character 0x%02X", *kp); |
||
1155 | png_warning(png_ptr, msg); |
||
1156 | #else |
||
1157 | png_warning(png_ptr, "invalid character in keyword"); |
||
1158 | #endif |
||
1159 | *dp = ' '; |
||
1160 | } |
||
1161 | else |
||
1162 | { |
||
1163 | *dp = *kp; |
||
1164 | } |
||
1165 | } |
||
1166 | *dp = '\0'; |
||
1167 | |||
1168 | /* Remove any trailing white space. */ |
||
1169 | kp = *new_key + key_len - 1; |
||
1170 | if (*kp == ' ') |
||
1171 | { |
||
1172 | png_warning(png_ptr, "trailing spaces removed from keyword"); |
||
1173 | |||
1174 | while (*kp == ' ') |
||
1175 | { |
||
1176 | *(kp--) = '\0'; |
||
1177 | key_len--; |
||
1178 | } |
||
1179 | } |
||
1180 | |||
1181 | /* Remove any leading white space. */ |
||
1182 | kp = *new_key; |
||
1183 | if (*kp == ' ') |
||
1184 | { |
||
1185 | png_warning(png_ptr, "leading spaces removed from keyword"); |
||
1186 | |||
1187 | while (*kp == ' ') |
||
1188 | { |
||
1189 | kp++; |
||
1190 | key_len--; |
||
1191 | } |
||
1192 | } |
||
1193 | |||
1194 | png_debug1(2, "Checking for multiple internal spaces in '%s'\n", kp); |
||
1195 | |||
1196 | /* Remove multiple internal spaces. */ |
||
1197 | for (kflag = 0, dp = *new_key; *kp != '\0'; kp++) |
||
1198 | { |
||
1199 | if (*kp == ' ' && kflag == 0) |
||
1200 | { |
||
1201 | *(dp++) = *kp; |
||
1202 | kflag = 1; |
||
1203 | } |
||
1204 | else if (*kp == ' ') |
||
1205 | { |
||
1206 | key_len--; |
||
1207 | kwarn=1; |
||
1208 | } |
||
1209 | else |
||
1210 | { |
||
1211 | *(dp++) = *kp; |
||
1212 | kflag = 0; |
||
1213 | } |
||
1214 | } |
||
1215 | *dp = '\0'; |
||
1216 | if(kwarn) |
||
1217 | png_warning(png_ptr, "extra interior spaces removed from keyword"); |
||
1218 | |||
1219 | if (key_len == 0) |
||
1220 | { |
||
1221 | png_free(png_ptr, *new_key); |
||
1222 | *new_key=NULL; |
||
1223 | png_warning(png_ptr, "Zero length keyword"); |
||
1224 | } |
||
1225 | |||
1226 | if (key_len > 79) |
||
1227 | { |
||
1228 | png_warning(png_ptr, "keyword length must be 1 - 79 characters"); |
||
1229 | new_key[79] = '\0'; |
||
1230 | key_len = 79; |
||
1231 | } |
||
1232 | |||
1233 | return (key_len); |
||
1234 | } |
||
1235 | #endif |
||
1236 | |||
1237 | #if defined(PNG_WRITE_tEXt_SUPPORTED) |
||
1238 | /* write a tEXt chunk */ |
||
1239 | void /* PRIVATE */ |
||
1240 | png_write_tEXt(png_structp png_ptr, png_charp key, png_charp text, |
||
1241 | png_size_t text_len) |
||
1242 | { |
||
1243 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
1244 | PNG_tEXt; |
||
1245 | #endif |
||
1246 | png_size_t key_len; |
||
1247 | png_charp new_key; |
||
1248 | |||
1249 | png_debug(1, "in png_write_tEXt\n"); |
||
1250 | if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0) |
||
1251 | { |
||
1252 | png_warning(png_ptr, "Empty keyword in tEXt chunk"); |
||
1253 | return; |
||
1254 | } |
||
1255 | |||
1256 | if (text == NULL || *text == '\0') |
||
1257 | text_len = 0; |
||
1258 | else |
||
1259 | text_len = png_strlen(text); |
||
1260 | |||
1261 | /* make sure we include the 0 after the key */ |
||
1262 | png_write_chunk_start(png_ptr, (png_bytep)png_tEXt, (png_uint_32)key_len+text_len+1); |
||
1263 | /* |
||
1264 | * We leave it to the application to meet PNG-1.0 requirements on the |
||
1265 | * contents of the text. PNG-1.0 through PNG-1.2 discourage the use of |
||
1266 | * any non-Latin-1 characters except for NEWLINE. ISO PNG will forbid them. |
||
1267 | * The NUL character is forbidden by PNG-1.0 through PNG-1.2 and ISO PNG. |
||
1268 | */ |
||
1269 | png_write_chunk_data(png_ptr, (png_bytep)new_key, key_len + 1); |
||
1270 | if (text_len) |
||
1271 | png_write_chunk_data(png_ptr, (png_bytep)text, text_len); |
||
1272 | |||
1273 | png_write_chunk_end(png_ptr); |
||
1274 | png_free(png_ptr, new_key); |
||
1275 | } |
||
1276 | #endif |
||
1277 | |||
1278 | #if defined(PNG_WRITE_zTXt_SUPPORTED) |
||
1279 | /* write a compressed text chunk */ |
||
1280 | void /* PRIVATE */ |
||
1281 | png_write_zTXt(png_structp png_ptr, png_charp key, png_charp text, |
||
1282 | png_size_t text_len, int compression) |
||
1283 | { |
||
1284 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
1285 | PNG_zTXt; |
||
1286 | #endif |
||
1287 | png_size_t key_len; |
||
1288 | char buf[1]; |
||
1289 | png_charp new_key; |
||
1290 | compression_state comp; |
||
1291 | |||
1292 | png_debug(1, "in png_write_zTXt\n"); |
||
1293 | |||
1294 | if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0) |
||
1295 | { |
||
1296 | png_warning(png_ptr, "Empty keyword in zTXt chunk"); |
||
1297 | return; |
||
1298 | } |
||
1299 | |||
1300 | if (text == NULL || *text == '\0' || compression==PNG_TEXT_COMPRESSION_NONE) |
||
1301 | { |
||
1302 | png_write_tEXt(png_ptr, new_key, text, (png_size_t)0); |
||
1303 | png_free(png_ptr, new_key); |
||
1304 | return; |
||
1305 | } |
||
1306 | |||
1307 | text_len = png_strlen(text); |
||
1308 | |||
1309 | png_free(png_ptr, new_key); |
||
1310 | |||
1311 | /* compute the compressed data; do it now for the length */ |
||
1312 | text_len = png_text_compress(png_ptr, text, text_len, compression, |
||
1313 | &comp); |
||
1314 | |||
1315 | /* write start of chunk */ |
||
1316 | png_write_chunk_start(png_ptr, (png_bytep)png_zTXt, (png_uint_32) |
||
1317 | (key_len+text_len+2)); |
||
1318 | /* write key */ |
||
1319 | png_write_chunk_data(png_ptr, (png_bytep)key, key_len + 1); |
||
1320 | buf[0] = (png_byte)compression; |
||
1321 | /* write compression */ |
||
1322 | png_write_chunk_data(png_ptr, (png_bytep)buf, (png_size_t)1); |
||
1323 | /* write the compressed data */ |
||
1324 | png_write_compressed_data_out(png_ptr, &comp); |
||
1325 | |||
1326 | /* close the chunk */ |
||
1327 | png_write_chunk_end(png_ptr); |
||
1328 | } |
||
1329 | #endif |
||
1330 | |||
1331 | #if defined(PNG_WRITE_iTXt_SUPPORTED) |
||
1332 | /* write an iTXt chunk */ |
||
1333 | void /* PRIVATE */ |
||
1334 | png_write_iTXt(png_structp png_ptr, int compression, png_charp key, |
||
1335 | png_charp lang, png_charp lang_key, png_charp text) |
||
1336 | { |
||
1337 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
1338 | PNG_iTXt; |
||
1339 | #endif |
||
1340 | png_size_t lang_len, key_len, lang_key_len, text_len; |
||
1341 | png_charp new_lang, new_key; |
||
1342 | png_byte cbuf[2]; |
||
1343 | compression_state comp; |
||
1344 | |||
1345 | png_debug(1, "in png_write_iTXt\n"); |
||
1346 | |||
1347 | if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0) |
||
1348 | { |
||
1349 | png_warning(png_ptr, "Empty keyword in iTXt chunk"); |
||
1350 | return; |
||
1351 | } |
||
1352 | if (lang == NULL || (lang_len = png_check_keyword(png_ptr, lang, &new_lang))==0) |
||
1353 | { |
||
1354 | png_warning(png_ptr, "Empty language field in iTXt chunk"); |
||
1355 | new_lang = NULL; |
||
1356 | lang_len = 0; |
||
1357 | } |
||
1358 | |||
1359 | if (lang_key == NULL) |
||
1360 | lang_key_len = 0; |
||
1361 | else |
||
1362 | lang_key_len = png_strlen(lang_key); |
||
1363 | |||
1364 | if (text == NULL) |
||
1365 | text_len = 0; |
||
1366 | else |
||
1367 | text_len = png_strlen(text); |
||
1368 | |||
1369 | /* compute the compressed data; do it now for the length */ |
||
1370 | text_len = png_text_compress(png_ptr, text, text_len, compression-2, |
||
1371 | &comp); |
||
1372 | |||
1373 | |||
1374 | /* make sure we include the compression flag, the compression byte, |
||
1375 | * and the NULs after the key, lang, and lang_key parts */ |
||
1376 | |||
1377 | png_write_chunk_start(png_ptr, (png_bytep)png_iTXt, |
||
1378 | (png_uint_32)( |
||
1379 | 5 /* comp byte, comp flag, terminators for key, lang and lang_key */ |
||
1380 | + key_len |
||
1381 | + lang_len |
||
1382 | + lang_key_len |
||
1383 | + text_len)); |
||
1384 | |||
1385 | /* |
||
1386 | * We leave it to the application to meet PNG-1.0 requirements on the |
||
1387 | * contents of the text. PNG-1.0 through PNG-1.2 discourage the use of |
||
1388 | * any non-Latin-1 characters except for NEWLINE. ISO PNG will forbid them. |
||
1389 | * The NUL character is forbidden by PNG-1.0 through PNG-1.2 and ISO PNG. |
||
1390 | */ |
||
1391 | png_write_chunk_data(png_ptr, (png_bytep)new_key, key_len + 1); |
||
1392 | |||
1393 | /* set the compression flag */ |
||
1394 | if (compression == PNG_ITXT_COMPRESSION_NONE || \ |
||
1395 | compression == PNG_TEXT_COMPRESSION_NONE) |
||
1396 | cbuf[0] = 0; |
||
1397 | else /* compression == PNG_ITXT_COMPRESSION_zTXt */ |
||
1398 | cbuf[0] = 1; |
||
1399 | /* set the compression method */ |
||
1400 | cbuf[1] = 0; |
||
1401 | png_write_chunk_data(png_ptr, cbuf, 2); |
||
1402 | |||
1403 | cbuf[0] = 0; |
||
1404 | png_write_chunk_data(png_ptr, (new_lang ? (png_bytep)new_lang : cbuf), lang_len + 1); |
||
1405 | png_write_chunk_data(png_ptr, (lang_key ? (png_bytep)lang_key : cbuf), lang_key_len + 1); |
||
1406 | png_write_compressed_data_out(png_ptr, &comp); |
||
1407 | |||
1408 | png_write_chunk_end(png_ptr); |
||
1409 | png_free(png_ptr, new_key); |
||
1410 | if (new_lang) |
||
1411 | png_free(png_ptr, new_lang); |
||
1412 | } |
||
1413 | #endif |
||
1414 | |||
1415 | #if defined(PNG_WRITE_oFFs_SUPPORTED) |
||
1416 | /* write the oFFs chunk */ |
||
1417 | void /* PRIVATE */ |
||
1418 | png_write_oFFs(png_structp png_ptr, png_int_32 x_offset, png_int_32 y_offset, |
||
1419 | int unit_type) |
||
1420 | { |
||
1421 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
1422 | PNG_oFFs; |
||
1423 | #endif |
||
1424 | png_byte buf[9]; |
||
1425 | |||
1426 | png_debug(1, "in png_write_oFFs\n"); |
||
1427 | if (unit_type >= PNG_OFFSET_LAST) |
||
1428 | png_warning(png_ptr, "Unrecognized unit type for oFFs chunk"); |
||
1429 | |||
1430 | png_save_int_32(buf, x_offset); |
||
1431 | png_save_int_32(buf + 4, y_offset); |
||
1432 | buf[8] = (png_byte)unit_type; |
||
1433 | |||
1434 | png_write_chunk(png_ptr, (png_bytep)png_oFFs, buf, (png_size_t)9); |
||
1435 | } |
||
1436 | #endif |
||
1437 | |||
1438 | #if defined(PNG_WRITE_pCAL_SUPPORTED) |
||
1439 | /* write the pCAL chunk (described in the PNG extensions document) */ |
||
1440 | void /* PRIVATE */ |
||
1441 | png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0, |
||
1442 | png_int_32 X1, int type, int nparams, png_charp units, png_charpp params) |
||
1443 | { |
||
1444 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
1445 | PNG_pCAL; |
||
1446 | #endif |
||
1447 | png_size_t purpose_len, units_len, total_len; |
||
1448 | png_uint_32p params_len; |
||
1449 | png_byte buf[10]; |
||
1450 | png_charp new_purpose; |
||
1451 | int i; |
||
1452 | |||
1453 | png_debug1(1, "in png_write_pCAL (%d parameters)\n", nparams); |
||
1454 | if (type >= PNG_EQUATION_LAST) |
||
1455 | png_warning(png_ptr, "Unrecognized equation type for pCAL chunk"); |
||
1456 | |||
1457 | purpose_len = png_check_keyword(png_ptr, purpose, &new_purpose) + 1; |
||
1458 | png_debug1(3, "pCAL purpose length = %d\n", (int)purpose_len); |
||
1459 | units_len = png_strlen(units) + (nparams == 0 ? 0 : 1); |
||
1460 | png_debug1(3, "pCAL units length = %d\n", (int)units_len); |
||
1461 | total_len = purpose_len + units_len + 10; |
||
1462 | |||
1463 | params_len = (png_uint_32p)png_malloc(png_ptr, (png_uint_32)(nparams |
||
1464 | *sizeof(png_uint_32))); |
||
1465 | |||
1466 | /* Find the length of each parameter, making sure we don't count the |
||
1467 | null terminator for the last parameter. */ |
||
1468 | for (i = 0; i < nparams; i++) |
||
1469 | { |
||
1470 | params_len[i] = png_strlen(params[i]) + (i == nparams - 1 ? 0 : 1); |
||
1471 | png_debug2(3, "pCAL parameter %d length = %lu\n", i, params_len[i]); |
||
1472 | total_len += (png_size_t)params_len[i]; |
||
1473 | } |
||
1474 | |||
1475 | png_debug1(3, "pCAL total length = %d\n", (int)total_len); |
||
1476 | png_write_chunk_start(png_ptr, (png_bytep)png_pCAL, (png_uint_32)total_len); |
||
1477 | png_write_chunk_data(png_ptr, (png_bytep)new_purpose, purpose_len); |
||
1478 | png_save_int_32(buf, X0); |
||
1479 | png_save_int_32(buf + 4, X1); |
||
1480 | buf[8] = (png_byte)type; |
||
1481 | buf[9] = (png_byte)nparams; |
||
1482 | png_write_chunk_data(png_ptr, buf, (png_size_t)10); |
||
1483 | png_write_chunk_data(png_ptr, (png_bytep)units, (png_size_t)units_len); |
||
1484 | |||
1485 | png_free(png_ptr, new_purpose); |
||
1486 | |||
1487 | for (i = 0; i < nparams; i++) |
||
1488 | { |
||
1489 | png_write_chunk_data(png_ptr, (png_bytep)params[i], |
||
1490 | (png_size_t)params_len[i]); |
||
1491 | } |
||
1492 | |||
1493 | png_free(png_ptr, params_len); |
||
1494 | png_write_chunk_end(png_ptr); |
||
1495 | } |
||
1496 | #endif |
||
1497 | |||
1498 | #if defined(PNG_WRITE_sCAL_SUPPORTED) |
||
1499 | /* write the sCAL chunk */ |
||
1500 | #if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO) |
||
1501 | void /* PRIVATE */ |
||
1502 | png_write_sCAL(png_structp png_ptr, int unit, double width,double height) |
||
1503 | { |
||
1504 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
1505 | PNG_sCAL; |
||
1506 | #endif |
||
1507 | png_size_t total_len; |
||
1508 | char wbuf[32], hbuf[32]; |
||
1509 | |||
1510 | png_debug(1, "in png_write_sCAL\n"); |
||
1511 | |||
1512 | #if defined(_WIN32_WCE) |
||
1513 | /* sprintf() function is not supported on WindowsCE */ |
||
1514 | { |
||
1515 | wchar_t wc_buf[32]; |
||
1516 | swprintf(wc_buf, TEXT("%12.12e"), width); |
||
1517 | WideCharToMultiByte(CP_ACP, 0, wc_buf, -1, wbuf, 32, NULL, NULL); |
||
1518 | swprintf(wc_buf, TEXT("%12.12e"), height); |
||
1519 | WideCharToMultiByte(CP_ACP, 0, wc_buf, -1, hbuf, 32, NULL, NULL); |
||
1520 | } |
||
1521 | #else |
||
1522 | sprintf(wbuf, "%12.12e", width); |
||
1523 | sprintf(hbuf, "%12.12e", height); |
||
1524 | #endif |
||
1525 | total_len = 1 + png_strlen(wbuf)+1 + png_strlen(hbuf); |
||
1526 | |||
1527 | png_debug1(3, "sCAL total length = %d\n", (int)total_len); |
||
1528 | png_write_chunk_start(png_ptr, (png_bytep)png_sCAL, (png_uint_32)total_len); |
||
1529 | png_write_chunk_data(png_ptr, (png_bytep)&unit, 1); |
||
1530 | png_write_chunk_data(png_ptr, (png_bytep)wbuf, png_strlen(wbuf)+1); |
||
1531 | png_write_chunk_data(png_ptr, (png_bytep)hbuf, png_strlen(hbuf)); |
||
1532 | |||
1533 | png_write_chunk_end(png_ptr); |
||
1534 | } |
||
1535 | #else |
||
1536 | #ifdef PNG_FIXED_POINT_SUPPORTED |
||
1537 | void /* PRIVATE */ |
||
1538 | png_write_sCAL_s(png_structp png_ptr, int unit, png_charp width, |
||
1539 | png_charp height) |
||
1540 | { |
||
1541 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
1542 | PNG_sCAL; |
||
1543 | #endif |
||
1544 | png_size_t total_len; |
||
1545 | char wbuf[32], hbuf[32]; |
||
1546 | |||
1547 | png_debug(1, "in png_write_sCAL_s\n"); |
||
1548 | |||
1549 | png_strcpy(wbuf,(const char *)width); |
||
1550 | png_strcpy(hbuf,(const char *)height); |
||
1551 | total_len = 1 + png_strlen(wbuf)+1 + png_strlen(hbuf); |
||
1552 | |||
1553 | png_debug1(3, "sCAL total length = %d\n", total_len); |
||
1554 | png_write_chunk_start(png_ptr, (png_bytep)png_sCAL, (png_uint_32)total_len); |
||
1555 | png_write_chunk_data(png_ptr, (png_bytep)&unit, 1); |
||
1556 | png_write_chunk_data(png_ptr, (png_bytep)wbuf, png_strlen(wbuf)+1); |
||
1557 | png_write_chunk_data(png_ptr, (png_bytep)hbuf, png_strlen(hbuf)); |
||
1558 | |||
1559 | png_write_chunk_end(png_ptr); |
||
1560 | } |
||
1561 | #endif |
||
1562 | #endif |
||
1563 | #endif |
||
1564 | |||
1565 | #if defined(PNG_WRITE_pHYs_SUPPORTED) |
||
1566 | /* write the pHYs chunk */ |
||
1567 | void /* PRIVATE */ |
||
1568 | png_write_pHYs(png_structp png_ptr, png_uint_32 x_pixels_per_unit, |
||
1569 | png_uint_32 y_pixels_per_unit, |
||
1570 | int unit_type) |
||
1571 | { |
||
1572 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
1573 | PNG_pHYs; |
||
1574 | #endif |
||
1575 | png_byte buf[9]; |
||
1576 | |||
1577 | png_debug(1, "in png_write_pHYs\n"); |
||
1578 | if (unit_type >= PNG_RESOLUTION_LAST) |
||
1579 | png_warning(png_ptr, "Unrecognized unit type for pHYs chunk"); |
||
1580 | |||
1581 | png_save_uint_32(buf, x_pixels_per_unit); |
||
1582 | png_save_uint_32(buf + 4, y_pixels_per_unit); |
||
1583 | buf[8] = (png_byte)unit_type; |
||
1584 | |||
1585 | png_write_chunk(png_ptr, (png_bytep)png_pHYs, buf, (png_size_t)9); |
||
1586 | } |
||
1587 | #endif |
||
1588 | |||
1589 | #if defined(PNG_WRITE_tIME_SUPPORTED) |
||
1590 | /* Write the tIME chunk. Use either png_convert_from_struct_tm() |
||
1591 | * or png_convert_from_time_t(), or fill in the structure yourself. |
||
1592 | */ |
||
1593 | void /* PRIVATE */ |
||
1594 | png_write_tIME(png_structp png_ptr, png_timep mod_time) |
||
1595 | { |
||
1596 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
1597 | PNG_tIME; |
||
1598 | #endif |
||
1599 | png_byte buf[7]; |
||
1600 | |||
1601 | png_debug(1, "in png_write_tIME\n"); |
||
1602 | if (mod_time->month > 12 || mod_time->month < 1 || |
||
1603 | mod_time->day > 31 || mod_time->day < 1 || |
||
1604 | mod_time->hour > 23 || mod_time->second > 60) |
||
1605 | { |
||
1606 | png_warning(png_ptr, "Invalid time specified for tIME chunk"); |
||
1607 | return; |
||
1608 | } |
||
1609 | |||
1610 | png_save_uint_16(buf, mod_time->year); |
||
1611 | buf[2] = mod_time->month; |
||
1612 | buf[3] = mod_time->day; |
||
1613 | buf[4] = mod_time->hour; |
||
1614 | buf[5] = mod_time->minute; |
||
1615 | buf[6] = mod_time->second; |
||
1616 | |||
1617 | png_write_chunk(png_ptr, (png_bytep)png_tIME, buf, (png_size_t)7); |
||
1618 | } |
||
1619 | #endif |
||
1620 | |||
1621 | /* initializes the row writing capability of libpng */ |
||
1622 | void /* PRIVATE */ |
||
1623 | png_write_start_row(png_structp png_ptr) |
||
1624 | { |
||
1625 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
1626 | /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */ |
||
1627 | |||
1628 | /* start of interlace block */ |
||
1629 | int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0}; |
||
1630 | |||
1631 | /* offset to next interlace block */ |
||
1632 | int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; |
||
1633 | |||
1634 | /* start of interlace block in the y direction */ |
||
1635 | int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1}; |
||
1636 | |||
1637 | /* offset to next interlace block in the y direction */ |
||
1638 | int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2}; |
||
1639 | #endif |
||
1640 | |||
1641 | png_size_t buf_size; |
||
1642 | |||
1643 | png_debug(1, "in png_write_start_row\n"); |
||
1644 | buf_size = (png_size_t)(((png_ptr->width * png_ptr->usr_channels * |
||
1645 | png_ptr->usr_bit_depth + 7) >> 3) + 1); |
||
1646 | |||
1647 | /* set up row buffer */ |
||
1648 | png_ptr->row_buf = (png_bytep)png_malloc(png_ptr, (png_uint_32)buf_size); |
||
1649 | png_ptr->row_buf[0] = PNG_FILTER_VALUE_NONE; |
||
1650 | |||
1651 | /* set up filtering buffer, if using this filter */ |
||
1652 | if (png_ptr->do_filter & PNG_FILTER_SUB) |
||
1653 | { |
||
1654 | png_ptr->sub_row = (png_bytep)png_malloc(png_ptr, |
||
1655 | (png_ptr->rowbytes + 1)); |
||
1656 | png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB; |
||
1657 | } |
||
1658 | |||
1659 | /* We only need to keep the previous row if we are using one of these. */ |
||
1660 | if (png_ptr->do_filter & (PNG_FILTER_AVG | PNG_FILTER_UP | PNG_FILTER_PAETH)) |
||
1661 | { |
||
1662 | /* set up previous row buffer */ |
||
1663 | png_ptr->prev_row = (png_bytep)png_malloc(png_ptr, (png_uint_32)buf_size); |
||
1664 | png_memset(png_ptr->prev_row, 0, buf_size); |
||
1665 | |||
1666 | if (png_ptr->do_filter & PNG_FILTER_UP) |
||
1667 | { |
||
1668 | png_ptr->up_row = (png_bytep )png_malloc(png_ptr, |
||
1669 | (png_ptr->rowbytes + 1)); |
||
1670 | png_ptr->up_row[0] = PNG_FILTER_VALUE_UP; |
||
1671 | } |
||
1672 | |||
1673 | if (png_ptr->do_filter & PNG_FILTER_AVG) |
||
1674 | { |
||
1675 | png_ptr->avg_row = (png_bytep)png_malloc(png_ptr, |
||
1676 | (png_ptr->rowbytes + 1)); |
||
1677 | png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG; |
||
1678 | } |
||
1679 | |||
1680 | if (png_ptr->do_filter & PNG_FILTER_PAETH) |
||
1681 | { |
||
1682 | png_ptr->paeth_row = (png_bytep )png_malloc(png_ptr, |
||
1683 | (png_ptr->rowbytes + 1)); |
||
1684 | png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH; |
||
1685 | } |
||
1686 | } |
||
1687 | |||
1688 | #ifdef PNG_WRITE_INTERLACING_SUPPORTED |
||
1689 | /* if interlaced, we need to set up width and height of pass */ |
||
1690 | if (png_ptr->interlaced) |
||
1691 | { |
||
1692 | if (!(png_ptr->transformations & PNG_INTERLACE)) |
||
1693 | { |
||
1694 | png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 - |
||
1695 | png_pass_ystart[0]) / png_pass_yinc[0]; |
||
1696 | png_ptr->usr_width = (png_ptr->width + png_pass_inc[0] - 1 - |
||
1697 | png_pass_start[0]) / png_pass_inc[0]; |
||
1698 | } |
||
1699 | else |
||
1700 | { |
||
1701 | png_ptr->num_rows = png_ptr->height; |
||
1702 | png_ptr->usr_width = png_ptr->width; |
||
1703 | } |
||
1704 | } |
||
1705 | else |
||
1706 | #endif |
||
1707 | { |
||
1708 | png_ptr->num_rows = png_ptr->height; |
||
1709 | png_ptr->usr_width = png_ptr->width; |
||
1710 | } |
||
1711 | png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; |
||
1712 | png_ptr->zstream.next_out = png_ptr->zbuf; |
||
1713 | } |
||
1714 | |||
1715 | /* Internal use only. Called when finished processing a row of data. */ |
||
1716 | void /* PRIVATE */ |
||
1717 | png_write_finish_row(png_structp png_ptr) |
||
1718 | { |
||
1719 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
1720 | /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */ |
||
1721 | |||
1722 | /* start of interlace block */ |
||
1723 | int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0}; |
||
1724 | |||
1725 | /* offset to next interlace block */ |
||
1726 | int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; |
||
1727 | |||
1728 | /* start of interlace block in the y direction */ |
||
1729 | int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1}; |
||
1730 | |||
1731 | /* offset to next interlace block in the y direction */ |
||
1732 | int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2}; |
||
1733 | #endif |
||
1734 | |||
1735 | int ret; |
||
1736 | |||
1737 | png_debug(1, "in png_write_finish_row\n"); |
||
1738 | /* next row */ |
||
1739 | png_ptr->row_number++; |
||
1740 | |||
1741 | /* see if we are done */ |
||
1742 | if (png_ptr->row_number < png_ptr->num_rows) |
||
1743 | return; |
||
1744 | |||
1745 | #ifdef PNG_WRITE_INTERLACING_SUPPORTED |
||
1746 | /* if interlaced, go to next pass */ |
||
1747 | if (png_ptr->interlaced) |
||
1748 | { |
||
1749 | png_ptr->row_number = 0; |
||
1750 | if (png_ptr->transformations & PNG_INTERLACE) |
||
1751 | { |
||
1752 | png_ptr->pass++; |
||
1753 | } |
||
1754 | else |
||
1755 | { |
||
1756 | /* loop until we find a non-zero width or height pass */ |
||
1757 | do |
||
1758 | { |
||
1759 | png_ptr->pass++; |
||
1760 | if (png_ptr->pass >= 7) |
||
1761 | break; |
||
1762 | png_ptr->usr_width = (png_ptr->width + |
||
1763 | png_pass_inc[png_ptr->pass] - 1 - |
||
1764 | png_pass_start[png_ptr->pass]) / |
||
1765 | png_pass_inc[png_ptr->pass]; |
||
1766 | png_ptr->num_rows = (png_ptr->height + |
||
1767 | png_pass_yinc[png_ptr->pass] - 1 - |
||
1768 | png_pass_ystart[png_ptr->pass]) / |
||
1769 | png_pass_yinc[png_ptr->pass]; |
||
1770 | if (png_ptr->transformations & PNG_INTERLACE) |
||
1771 | break; |
||
1772 | } while (png_ptr->usr_width == 0 || png_ptr->num_rows == 0); |
||
1773 | |||
1774 | } |
||
1775 | |||
1776 | /* reset the row above the image for the next pass */ |
||
1777 | if (png_ptr->pass < 7) |
||
1778 | { |
||
1779 | if (png_ptr->prev_row != NULL) |
||
1780 | png_memset(png_ptr->prev_row, 0, |
||
1781 | (png_size_t) (((png_uint_32)png_ptr->usr_channels * |
||
1782 | (png_uint_32)png_ptr->usr_bit_depth * |
||
1783 | png_ptr->width + 7) >> 3) + 1); |
||
1784 | return; |
||
1785 | } |
||
1786 | } |
||
1787 | #endif |
||
1788 | |||
1789 | /* if we get here, we've just written the last row, so we need |
||
1790 | to flush the compressor */ |
||
1791 | do |
||
1792 | { |
||
1793 | /* tell the compressor we are done */ |
||
1794 | ret = deflate(&png_ptr->zstream, Z_FINISH); |
||
1795 | /* check for an error */ |
||
1796 | if (ret == Z_OK) |
||
1797 | { |
||
1798 | /* check to see if we need more room */ |
||
1799 | if (!(png_ptr->zstream.avail_out)) |
||
1800 | { |
||
1801 | png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size); |
||
1802 | png_ptr->zstream.next_out = png_ptr->zbuf; |
||
1803 | png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; |
||
1804 | } |
||
1805 | } |
||
1806 | else if (ret != Z_STREAM_END) |
||
1807 | { |
||
1808 | if (png_ptr->zstream.msg != NULL) |
||
1809 | png_error(png_ptr, png_ptr->zstream.msg); |
||
1810 | else |
||
1811 | png_error(png_ptr, "zlib error"); |
||
1812 | } |
||
1813 | } while (ret != Z_STREAM_END); |
||
1814 | |||
1815 | /* write any extra space */ |
||
1816 | if (png_ptr->zstream.avail_out < png_ptr->zbuf_size) |
||
1817 | { |
||
1818 | png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size - |
||
1819 | png_ptr->zstream.avail_out); |
||
1820 | } |
||
1821 | |||
1822 | deflateReset(&png_ptr->zstream); |
||
1823 | } |
||
1824 | |||
1825 | #if defined(PNG_WRITE_INTERLACING_SUPPORTED) |
||
1826 | /* Pick out the correct pixels for the interlace pass. |
||
1827 | * The basic idea here is to go through the row with a source |
||
1828 | * pointer and a destination pointer (sp and dp), and copy the |
||
1829 | * correct pixels for the pass. As the row gets compacted, |
||
1830 | * sp will always be >= dp, so we should never overwrite anything. |
||
1831 | * See the default: case for the easiest code to understand. |
||
1832 | */ |
||
1833 | void /* PRIVATE */ |
||
1834 | png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass) |
||
1835 | { |
||
1836 | #ifdef PNG_USE_LOCAL_ARRAYS |
||
1837 | /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */ |
||
1838 | |||
1839 | /* start of interlace block */ |
||
1840 | int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0}; |
||
1841 | |||
1842 | /* offset to next interlace block */ |
||
1843 | int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; |
||
1844 | #endif |
||
1845 | |||
1846 | png_debug(1, "in png_do_write_interlace\n"); |
||
1847 | /* we don't have to do anything on the last pass (6) */ |
||
1848 | #if defined(PNG_USELESS_TESTS_SUPPORTED) |
||
1849 | if (row != NULL && row_info != NULL && pass < 6) |
||
1850 | #else |
||
1851 | if (pass < 6) |
||
1852 | #endif |
||
1853 | { |
||
1854 | /* each pixel depth is handled separately */ |
||
1855 | switch (row_info->pixel_depth) |
||
1856 | { |
||
1857 | case 1: |
||
1858 | { |
||
1859 | png_bytep sp; |
||
1860 | png_bytep dp; |
||
1861 | int shift; |
||
1862 | int d; |
||
1863 | int value; |
||
1864 | png_uint_32 i; |
||
1865 | png_uint_32 row_width = row_info->width; |
||
1866 | |||
1867 | dp = row; |
||
1868 | d = 0; |
||
1869 | shift = 7; |
||
1870 | for (i = png_pass_start[pass]; i < row_width; |
||
1871 | i += png_pass_inc[pass]) |
||
1872 | { |
||
1873 | sp = row + (png_size_t)(i >> 3); |
||
1874 | value = (int)(*sp >> (7 - (int)(i & 0x07))) & 0x01; |
||
1875 | d |= (value << shift); |
||
1876 | |||
1877 | if (shift == 0) |
||
1878 | { |
||
1879 | shift = 7; |
||
1880 | *dp++ = (png_byte)d; |
||
1881 | d = 0; |
||
1882 | } |
||
1883 | else |
||
1884 | shift--; |
||
1885 | |||
1886 | } |
||
1887 | if (shift != 7) |
||
1888 | *dp = (png_byte)d; |
||
1889 | break; |
||
1890 | } |
||
1891 | case 2: |
||
1892 | { |
||
1893 | png_bytep sp; |
||
1894 | png_bytep dp; |
||
1895 | int shift; |
||
1896 | int d; |
||
1897 | int value; |
||
1898 | png_uint_32 i; |
||
1899 | png_uint_32 row_width = row_info->width; |
||
1900 | |||
1901 | dp = row; |
||
1902 | shift = 6; |
||
1903 | d = 0; |
||
1904 | for (i = png_pass_start[pass]; i < row_width; |
||
1905 | i += png_pass_inc[pass]) |
||
1906 | { |
||
1907 | sp = row + (png_size_t)(i >> 2); |
||
1908 | value = (*sp >> ((3 - (int)(i & 0x03)) << 1)) & 0x03; |
||
1909 | d |= (value << shift); |
||
1910 | |||
1911 | if (shift == 0) |
||
1912 | { |
||
1913 | shift = 6; |
||
1914 | *dp++ = (png_byte)d; |
||
1915 | d = 0; |
||
1916 | } |
||
1917 | else |
||
1918 | shift -= 2; |
||
1919 | } |
||
1920 | if (shift != 6) |
||
1921 | *dp = (png_byte)d; |
||
1922 | break; |
||
1923 | } |
||
1924 | case 4: |
||
1925 | { |
||
1926 | png_bytep sp; |
||
1927 | png_bytep dp; |
||
1928 | int shift; |
||
1929 | int d; |
||
1930 | int value; |
||
1931 | png_uint_32 i; |
||
1932 | png_uint_32 row_width = row_info->width; |
||
1933 | |||
1934 | dp = row; |
||
1935 | shift = 4; |
||
1936 | d = 0; |
||
1937 | for (i = png_pass_start[pass]; i < row_width; |
||
1938 | i += png_pass_inc[pass]) |
||
1939 | { |
||
1940 | sp = row + (png_size_t)(i >> 1); |
||
1941 | value = (*sp >> ((1 - (int)(i & 0x01)) << 2)) & 0x0f; |
||
1942 | d |= (value << shift); |
||
1943 | |||
1944 | if (shift == 0) |
||
1945 | { |
||
1946 | shift = 4; |
||
1947 | *dp++ = (png_byte)d; |
||
1948 | d = 0; |
||
1949 | } |
||
1950 | else |
||
1951 | shift -= 4; |
||
1952 | } |
||
1953 | if (shift != 4) |
||
1954 | *dp = (png_byte)d; |
||
1955 | break; |
||
1956 | } |
||
1957 | default: |
||
1958 | { |
||
1959 | png_bytep sp; |
||
1960 | png_bytep dp; |
||
1961 | png_uint_32 i; |
||
1962 | png_uint_32 row_width = row_info->width; |
||
1963 | png_size_t pixel_bytes; |
||
1964 | |||
1965 | /* start at the beginning */ |
||
1966 | dp = row; |
||
1967 | /* find out how many bytes each pixel takes up */ |
||
1968 | pixel_bytes = (row_info->pixel_depth >> 3); |
||
1969 | /* loop through the row, only looking at the pixels that |
||
1970 | matter */ |
||
1971 | for (i = png_pass_start[pass]; i < row_width; |
||
1972 | i += png_pass_inc[pass]) |
||
1973 | { |
||
1974 | /* find out where the original pixel is */ |
||
1975 | sp = row + (png_size_t)i * pixel_bytes; |
||
1976 | /* move the pixel */ |
||
1977 | if (dp != sp) |
||
1978 | png_memcpy(dp, sp, pixel_bytes); |
||
1979 | /* next pixel */ |
||
1980 | dp += pixel_bytes; |
||
1981 | } |
||
1982 | break; |
||
1983 | } |
||
1984 | } |
||
1985 | /* set new row width */ |
||
1986 | row_info->width = (row_info->width + |
||
1987 | png_pass_inc[pass] - 1 - |
||
1988 | png_pass_start[pass]) / |
||
1989 | png_pass_inc[pass]; |
||
1990 | row_info->rowbytes = ((row_info->width * |
||
1991 | row_info->pixel_depth + 7) >> 3); |
||
1992 | } |
||
1993 | } |
||
1994 | #endif |
||
1995 | |||
1996 | /* This filters the row, chooses which filter to use, if it has not already |
||
1997 | * been specified by the application, and then writes the row out with the |
||
1998 | * chosen filter. |
||
1999 | */ |
||
2000 | #define PNG_MAXSUM (~((png_uint_32)0) >> 1) |
||
2001 | #define PNG_HISHIFT 10 |
||
2002 | #define PNG_LOMASK ((png_uint_32)0xffffL) |
||
2003 | #define PNG_HIMASK ((png_uint_32)(~PNG_LOMASK >> PNG_HISHIFT)) |
||
2004 | void /* PRIVATE */ |
||
2005 | png_write_find_filter(png_structp png_ptr, png_row_infop row_info) |
||
2006 | { |
||
2007 | png_bytep prev_row, best_row, row_buf; |
||
2008 | png_uint_32 mins, bpp; |
||
2009 | png_byte filter_to_do = png_ptr->do_filter; |
||
2010 | png_uint_32 row_bytes = row_info->rowbytes; |
||
2011 | #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) |
||
2012 | int num_p_filters = (int)png_ptr->num_prev_filters; |
||
2013 | #endif |
||
2014 | |||
2015 | png_debug(1, "in png_write_find_filter\n"); |
||
2016 | /* find out how many bytes offset each pixel is */ |
||
2017 | bpp = (row_info->pixel_depth + 7) / 8; |
||
2018 | |||
2019 | prev_row = png_ptr->prev_row; |
||
2020 | best_row = row_buf = png_ptr->row_buf; |
||
2021 | mins = PNG_MAXSUM; |
||
2022 | |||
2023 | /* The prediction method we use is to find which method provides the |
||
2024 | * smallest value when summing the absolute values of the distances |
||
2025 | * from zero, using anything >= 128 as negative numbers. This is known |
||
2026 | * as the "minimum sum of absolute differences" heuristic. Other |
||
2027 | * heuristics are the "weighted minimum sum of absolute differences" |
||
2028 | * (experimental and can in theory improve compression), and the "zlib |
||
2029 | * predictive" method (not implemented yet), which does test compressions |
||
2030 | * of lines using different filter methods, and then chooses the |
||
2031 | * (series of) filter(s) that give minimum compressed data size (VERY |
||
2032 | * computationally expensive). |
||
2033 | * |
||
2034 | * GRR 980525: consider also |
||
2035 | * (1) minimum sum of absolute differences from running average (i.e., |
||
2036 | * keep running sum of non-absolute differences & count of bytes) |
||
2037 | * [track dispersion, too? restart average if dispersion too large?] |
||
2038 | * (1b) minimum sum of absolute differences from sliding average, probably |
||
2039 | * with window size <= deflate window (usually 32K) |
||
2040 | * (2) minimum sum of squared differences from zero or running average |
||
2041 | * (i.e., ~ root-mean-square approach) |
||
2042 | */ |
||
2043 | |||
2044 | |||
2045 | /* We don't need to test the 'no filter' case if this is the only filter |
||
2046 | * that has been chosen, as it doesn't actually do anything to the data. |
||
2047 | */ |
||
2048 | if ((filter_to_do & PNG_FILTER_NONE) && |
||
2049 | filter_to_do != PNG_FILTER_NONE) |
||
2050 | { |
||
2051 | png_bytep rp; |
||
2052 | png_uint_32 sum = 0; |
||
2053 | png_uint_32 i; |
||
2054 | int v; |
||
2055 | |||
2056 | for (i = 0, rp = row_buf + 1; i < row_bytes; i++, rp++) |
||
2057 | { |
||
2058 | v = *rp; |
||
2059 | sum += (v < 128) ? v : 256 - v; |
||
2060 | } |
||
2061 | |||
2062 | #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) |
||
2063 | if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) |
||
2064 | { |
||
2065 | png_uint_32 sumhi, sumlo; |
||
2066 | int j; |
||
2067 | sumlo = sum & PNG_LOMASK; |
||
2068 | sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; /* Gives us some footroom */ |
||
2069 | |||
2070 | /* Reduce the sum if we match any of the previous rows */ |
||
2071 | for (j = 0; j < num_p_filters; j++) |
||
2072 | { |
||
2073 | if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_NONE) |
||
2074 | { |
||
2075 | sumlo = (sumlo * png_ptr->filter_weights[j]) >> |
||
2076 | PNG_WEIGHT_SHIFT; |
||
2077 | sumhi = (sumhi * png_ptr->filter_weights[j]) >> |
||
2078 | PNG_WEIGHT_SHIFT; |
||
2079 | } |
||
2080 | } |
||
2081 | |||
2082 | /* Factor in the cost of this filter (this is here for completeness, |
||
2083 | * but it makes no sense to have a "cost" for the NONE filter, as |
||
2084 | * it has the minimum possible computational cost - none). |
||
2085 | */ |
||
2086 | sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_NONE]) >> |
||
2087 | PNG_COST_SHIFT; |
||
2088 | sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_NONE]) >> |
||
2089 | PNG_COST_SHIFT; |
||
2090 | |||
2091 | if (sumhi > PNG_HIMASK) |
||
2092 | sum = PNG_MAXSUM; |
||
2093 | else |
||
2094 | sum = (sumhi << PNG_HISHIFT) + sumlo; |
||
2095 | } |
||
2096 | #endif |
||
2097 | mins = sum; |
||
2098 | } |
||
2099 | |||
2100 | /* sub filter */ |
||
2101 | if (filter_to_do == PNG_FILTER_SUB) |
||
2102 | /* it's the only filter so no testing is needed */ |
||
2103 | { |
||
2104 | png_bytep rp, lp, dp; |
||
2105 | png_uint_32 i; |
||
2106 | for (i = 0, rp = row_buf + 1, dp = png_ptr->sub_row + 1; i < bpp; |
||
2107 | i++, rp++, dp++) |
||
2108 | { |
||
2109 | *dp = *rp; |
||
2110 | } |
||
2111 | for (lp = row_buf + 1; i < row_bytes; |
||
2112 | i++, rp++, lp++, dp++) |
||
2113 | { |
||
2114 | *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff); |
||
2115 | } |
||
2116 | best_row = png_ptr->sub_row; |
||
2117 | } |
||
2118 | |||
2119 | else if (filter_to_do & PNG_FILTER_SUB) |
||
2120 | { |
||
2121 | png_bytep rp, dp, lp; |
||
2122 | png_uint_32 sum = 0, lmins = mins; |
||
2123 | png_uint_32 i; |
||
2124 | int v; |
||
2125 | |||
2126 | #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) |
||
2127 | /* We temporarily increase the "minimum sum" by the factor we |
||
2128 | * would reduce the sum of this filter, so that we can do the |
||
2129 | * early exit comparison without scaling the sum each time. |
||
2130 | */ |
||
2131 | if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) |
||
2132 | { |
||
2133 | int j; |
||
2134 | png_uint_32 lmhi, lmlo; |
||
2135 | lmlo = lmins & PNG_LOMASK; |
||
2136 | lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK; |
||
2137 | |||
2138 | for (j = 0; j < num_p_filters; j++) |
||
2139 | { |
||
2140 | if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_SUB) |
||
2141 | { |
||
2142 | lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >> |
||
2143 | PNG_WEIGHT_SHIFT; |
||
2144 | lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >> |
||
2145 | PNG_WEIGHT_SHIFT; |
||
2146 | } |
||
2147 | } |
||
2148 | |||
2149 | lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >> |
||
2150 | PNG_COST_SHIFT; |
||
2151 | lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >> |
||
2152 | PNG_COST_SHIFT; |
||
2153 | |||
2154 | if (lmhi > PNG_HIMASK) |
||
2155 | lmins = PNG_MAXSUM; |
||
2156 | else |
||
2157 | lmins = (lmhi << PNG_HISHIFT) + lmlo; |
||
2158 | } |
||
2159 | #endif |
||
2160 | |||
2161 | for (i = 0, rp = row_buf + 1, dp = png_ptr->sub_row + 1; i < bpp; |
||
2162 | i++, rp++, dp++) |
||
2163 | { |
||
2164 | v = *dp = *rp; |
||
2165 | |||
2166 | sum += (v < 128) ? v : 256 - v; |
||
2167 | } |
||
2168 | for (lp = row_buf + 1; i < row_info->rowbytes; |
||
2169 | i++, rp++, lp++, dp++) |
||
2170 | { |
||
2171 | v = *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff); |
||
2172 | |||
2173 | sum += (v < 128) ? v : 256 - v; |
||
2174 | |||
2175 | if (sum > lmins) /* We are already worse, don't continue. */ |
||
2176 | break; |
||
2177 | } |
||
2178 | |||
2179 | #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) |
||
2180 | if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) |
||
2181 | { |
||
2182 | int j; |
||
2183 | png_uint_32 sumhi, sumlo; |
||
2184 | sumlo = sum & PNG_LOMASK; |
||
2185 | sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; |
||
2186 | |||
2187 | for (j = 0; j < num_p_filters; j++) |
||
2188 | { |
||
2189 | if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_SUB) |
||
2190 | { |
||
2191 | sumlo = (sumlo * png_ptr->inv_filter_weights[j]) >> |
||
2192 | PNG_WEIGHT_SHIFT; |
||
2193 | sumhi = (sumhi * png_ptr->inv_filter_weights[j]) >> |
||
2194 | PNG_WEIGHT_SHIFT; |
||
2195 | } |
||
2196 | } |
||
2197 | |||
2198 | sumlo = (sumlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >> |
||
2199 | PNG_COST_SHIFT; |
||
2200 | sumhi = (sumhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >> |
||
2201 | PNG_COST_SHIFT; |
||
2202 | |||
2203 | if (sumhi > PNG_HIMASK) |
||
2204 | sum = PNG_MAXSUM; |
||
2205 | else |
||
2206 | sum = (sumhi << PNG_HISHIFT) + sumlo; |
||
2207 | } |
||
2208 | #endif |
||
2209 | |||
2210 | if (sum < mins) |
||
2211 | { |
||
2212 | mins = sum; |
||
2213 | best_row = png_ptr->sub_row; |
||
2214 | } |
||
2215 | } |
||
2216 | |||
2217 | /* up filter */ |
||
2218 | if (filter_to_do == PNG_FILTER_UP) |
||
2219 | { |
||
2220 | png_bytep rp, dp, pp; |
||
2221 | png_uint_32 i; |
||
2222 | |||
2223 | for (i = 0, rp = row_buf + 1, dp = png_ptr->up_row + 1, |
||
2224 | pp = prev_row + 1; i < row_bytes; |
||
2225 | i++, rp++, pp++, dp++) |
||
2226 | { |
||
2227 | *dp = (png_byte)(((int)*rp - (int)*pp) & 0xff); |
||
2228 | } |
||
2229 | best_row = png_ptr->up_row; |
||
2230 | } |
||
2231 | |||
2232 | else if (filter_to_do & PNG_FILTER_UP) |
||
2233 | { |
||
2234 | png_bytep rp, dp, pp; |
||
2235 | png_uint_32 sum = 0, lmins = mins; |
||
2236 | png_uint_32 i; |
||
2237 | int v; |
||
2238 | |||
2239 | |||
2240 | #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) |
||
2241 | if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) |
||
2242 | { |
||
2243 | int j; |
||
2244 | png_uint_32 lmhi, lmlo; |
||
2245 | lmlo = lmins & PNG_LOMASK; |
||
2246 | lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK; |
||
2247 | |||
2248 | for (j = 0; j < num_p_filters; j++) |
||
2249 | { |
||
2250 | if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_UP) |
||
2251 | { |
||
2252 | lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >> |
||
2253 | PNG_WEIGHT_SHIFT; |
||
2254 | lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >> |
||
2255 | PNG_WEIGHT_SHIFT; |
||
2256 | } |
||
2257 | } |
||
2258 | |||
2259 | lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_UP]) >> |
||
2260 | PNG_COST_SHIFT; |
||
2261 | lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_UP]) >> |
||
2262 | PNG_COST_SHIFT; |
||
2263 | |||
2264 | if (lmhi > PNG_HIMASK) |
||
2265 | lmins = PNG_MAXSUM; |
||
2266 | else |
||
2267 | lmins = (lmhi << PNG_HISHIFT) + lmlo; |
||
2268 | } |
||
2269 | #endif |
||
2270 | |||
2271 | for (i = 0, rp = row_buf + 1, dp = png_ptr->up_row + 1, |
||
2272 | pp = prev_row + 1; i < row_bytes; i++) |
||
2273 | { |
||
2274 | v = *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff); |
||
2275 | |||
2276 | sum += (v < 128) ? v : 256 - v; |
||
2277 | |||
2278 | if (sum > lmins) /* We are already worse, don't continue. */ |
||
2279 | break; |
||
2280 | } |
||
2281 | |||
2282 | #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) |
||
2283 | if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) |
||
2284 | { |
||
2285 | int j; |
||
2286 | png_uint_32 sumhi, sumlo; |
||
2287 | sumlo = sum & PNG_LOMASK; |
||
2288 | sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; |
||
2289 | |||
2290 | for (j = 0; j < num_p_filters; j++) |
||
2291 | { |
||
2292 | if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_UP) |
||
2293 | { |
||
2294 | sumlo = (sumlo * png_ptr->filter_weights[j]) >> |
||
2295 | PNG_WEIGHT_SHIFT; |
||
2296 | sumhi = (sumhi * png_ptr->filter_weights[j]) >> |
||
2297 | PNG_WEIGHT_SHIFT; |
||
2298 | } |
||
2299 | } |
||
2300 | |||
2301 | sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_UP]) >> |
||
2302 | PNG_COST_SHIFT; |
||
2303 | sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_UP]) >> |
||
2304 | PNG_COST_SHIFT; |
||
2305 | |||
2306 | if (sumhi > PNG_HIMASK) |
||
2307 | sum = PNG_MAXSUM; |
||
2308 | else |
||
2309 | sum = (sumhi << PNG_HISHIFT) + sumlo; |
||
2310 | } |
||
2311 | #endif |
||
2312 | |||
2313 | if (sum < mins) |
||
2314 | { |
||
2315 | mins = sum; |
||
2316 | best_row = png_ptr->up_row; |
||
2317 | } |
||
2318 | } |
||
2319 | |||
2320 | /* avg filter */ |
||
2321 | if (filter_to_do == PNG_FILTER_AVG) |
||
2322 | { |
||
2323 | png_bytep rp, dp, pp, lp; |
||
2324 | png_uint_32 i; |
||
2325 | for (i = 0, rp = row_buf + 1, dp = png_ptr->avg_row + 1, |
||
2326 | pp = prev_row + 1; i < bpp; i++) |
||
2327 | { |
||
2328 | *dp++ = (png_byte)(((int)*rp++ - ((int)*pp++ / 2)) & 0xff); |
||
2329 | } |
||
2330 | for (lp = row_buf + 1; i < row_bytes; i++) |
||
2331 | { |
||
2332 | *dp++ = (png_byte)(((int)*rp++ - (((int)*pp++ + (int)*lp++) / 2)) |
||
2333 | & 0xff); |
||
2334 | } |
||
2335 | best_row = png_ptr->avg_row; |
||
2336 | } |
||
2337 | |||
2338 | else if (filter_to_do & PNG_FILTER_AVG) |
||
2339 | { |
||
2340 | png_bytep rp, dp, pp, lp; |
||
2341 | png_uint_32 sum = 0, lmins = mins; |
||
2342 | png_uint_32 i; |
||
2343 | int v; |
||
2344 | |||
2345 | #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) |
||
2346 | if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) |
||
2347 | { |
||
2348 | int j; |
||
2349 | png_uint_32 lmhi, lmlo; |
||
2350 | lmlo = lmins & PNG_LOMASK; |
||
2351 | lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK; |
||
2352 | |||
2353 | for (j = 0; j < num_p_filters; j++) |
||
2354 | { |
||
2355 | if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_AVG) |
||
2356 | { |
||
2357 | lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >> |
||
2358 | PNG_WEIGHT_SHIFT; |
||
2359 | lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >> |
||
2360 | PNG_WEIGHT_SHIFT; |
||
2361 | } |
||
2362 | } |
||
2363 | |||
2364 | lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_AVG]) >> |
||
2365 | PNG_COST_SHIFT; |
||
2366 | lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_AVG]) >> |
||
2367 | PNG_COST_SHIFT; |
||
2368 | |||
2369 | if (lmhi > PNG_HIMASK) |
||
2370 | lmins = PNG_MAXSUM; |
||
2371 | else |
||
2372 | lmins = (lmhi << PNG_HISHIFT) + lmlo; |
||
2373 | } |
||
2374 | #endif |
||
2375 | |||
2376 | for (i = 0, rp = row_buf + 1, dp = png_ptr->avg_row + 1, |
||
2377 | pp = prev_row + 1; i < bpp; i++) |
||
2378 | { |
||
2379 | v = *dp++ = (png_byte)(((int)*rp++ - ((int)*pp++ / 2)) & 0xff); |
||
2380 | |||
2381 | sum += (v < 128) ? v : 256 - v; |
||
2382 | } |
||
2383 | for (lp = row_buf + 1; i < row_bytes; i++) |
||
2384 | { |
||
2385 | v = *dp++ = |
||
2386 | (png_byte)(((int)*rp++ - (((int)*pp++ + (int)*lp++) / 2)) & 0xff); |
||
2387 | |||
2388 | sum += (v < 128) ? v : 256 - v; |
||
2389 | |||
2390 | if (sum > lmins) /* We are already worse, don't continue. */ |
||
2391 | break; |
||
2392 | } |
||
2393 | |||
2394 | #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) |
||
2395 | if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) |
||
2396 | { |
||
2397 | int j; |
||
2398 | png_uint_32 sumhi, sumlo; |
||
2399 | sumlo = sum & PNG_LOMASK; |
||
2400 | sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; |
||
2401 | |||
2402 | for (j = 0; j < num_p_filters; j++) |
||
2403 | { |
||
2404 | if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_NONE) |
||
2405 | { |
||
2406 | sumlo = (sumlo * png_ptr->filter_weights[j]) >> |
||
2407 | PNG_WEIGHT_SHIFT; |
||
2408 | sumhi = (sumhi * png_ptr->filter_weights[j]) >> |
||
2409 | PNG_WEIGHT_SHIFT; |
||
2410 | } |
||
2411 | } |
||
2412 | |||
2413 | sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_AVG]) >> |
||
2414 | PNG_COST_SHIFT; |
||
2415 | sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_AVG]) >> |
||
2416 | PNG_COST_SHIFT; |
||
2417 | |||
2418 | if (sumhi > PNG_HIMASK) |
||
2419 | sum = PNG_MAXSUM; |
||
2420 | else |
||
2421 | sum = (sumhi << PNG_HISHIFT) + sumlo; |
||
2422 | } |
||
2423 | #endif |
||
2424 | |||
2425 | if (sum < mins) |
||
2426 | { |
||
2427 | mins = sum; |
||
2428 | best_row = png_ptr->avg_row; |
||
2429 | } |
||
2430 | } |
||
2431 | |||
2432 | /* Paeth filter */ |
||
2433 | if (filter_to_do == PNG_FILTER_PAETH) |
||
2434 | { |
||
2435 | png_bytep rp, dp, pp, cp, lp; |
||
2436 | png_uint_32 i; |
||
2437 | for (i = 0, rp = row_buf + 1, dp = png_ptr->paeth_row + 1, |
||
2438 | pp = prev_row + 1; i < bpp; i++) |
||
2439 | { |
||
2440 | *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff); |
||
2441 | } |
||
2442 | |||
2443 | for (lp = row_buf + 1, cp = prev_row + 1; i < row_bytes; i++) |
||
2444 | { |
||
2445 | int a, b, c, pa, pb, pc, p; |
||
2446 | |||
2447 | b = *pp++; |
||
2448 | c = *cp++; |
||
2449 | a = *lp++; |
||
2450 | |||
2451 | p = b - c; |
||
2452 | pc = a - c; |
||
2453 | |||
2454 | #ifdef PNG_USE_ABS |
||
2455 | pa = abs(p); |
||
2456 | pb = abs(pc); |
||
2457 | pc = abs(p + pc); |
||
2458 | #else |
||
2459 | pa = p < 0 ? -p : p; |
||
2460 | pb = pc < 0 ? -pc : pc; |
||
2461 | pc = (p + pc) < 0 ? -(p + pc) : p + pc; |
||
2462 | #endif |
||
2463 | |||
2464 | p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c; |
||
2465 | |||
2466 | *dp++ = (png_byte)(((int)*rp++ - p) & 0xff); |
||
2467 | } |
||
2468 | best_row = png_ptr->paeth_row; |
||
2469 | } |
||
2470 | |||
2471 | else if (filter_to_do & PNG_FILTER_PAETH) |
||
2472 | { |
||
2473 | png_bytep rp, dp, pp, cp, lp; |
||
2474 | png_uint_32 sum = 0, lmins = mins; |
||
2475 | png_uint_32 i; |
||
2476 | int v; |
||
2477 | |||
2478 | #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) |
||
2479 | if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) |
||
2480 | { |
||
2481 | int j; |
||
2482 | png_uint_32 lmhi, lmlo; |
||
2483 | lmlo = lmins & PNG_LOMASK; |
||
2484 | lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK; |
||
2485 | |||
2486 | for (j = 0; j < num_p_filters; j++) |
||
2487 | { |
||
2488 | if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_PAETH) |
||
2489 | { |
||
2490 | lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >> |
||
2491 | PNG_WEIGHT_SHIFT; |
||
2492 | lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >> |
||
2493 | PNG_WEIGHT_SHIFT; |
||
2494 | } |
||
2495 | } |
||
2496 | |||
2497 | lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_PAETH]) >> |
||
2498 | PNG_COST_SHIFT; |
||
2499 | lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_PAETH]) >> |
||
2500 | PNG_COST_SHIFT; |
||
2501 | |||
2502 | if (lmhi > PNG_HIMASK) |
||
2503 | lmins = PNG_MAXSUM; |
||
2504 | else |
||
2505 | lmins = (lmhi << PNG_HISHIFT) + lmlo; |
||
2506 | } |
||
2507 | #endif |
||
2508 | |||
2509 | for (i = 0, rp = row_buf + 1, dp = png_ptr->paeth_row + 1, |
||
2510 | pp = prev_row + 1; i < bpp; i++) |
||
2511 | { |
||
2512 | v = *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff); |
||
2513 | |||
2514 | sum += (v < 128) ? v : 256 - v; |
||
2515 | } |
||
2516 | |||
2517 | for (lp = row_buf + 1, cp = prev_row + 1; i < row_bytes; i++) |
||
2518 | { |
||
2519 | int a, b, c, pa, pb, pc, p; |
||
2520 | |||
2521 | b = *pp++; |
||
2522 | c = *cp++; |
||
2523 | a = *lp++; |
||
2524 | |||
2525 | #ifndef PNG_SLOW_PAETH |
||
2526 | p = b - c; |
||
2527 | pc = a - c; |
||
2528 | #ifdef PNG_USE_ABS |
||
2529 | pa = abs(p); |
||
2530 | pb = abs(pc); |
||
2531 | pc = abs(p + pc); |
||
2532 | #else |
||
2533 | pa = p < 0 ? -p : p; |
||
2534 | pb = pc < 0 ? -pc : pc; |
||
2535 | pc = (p + pc) < 0 ? -(p + pc) : p + pc; |
||
2536 | #endif |
||
2537 | p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c; |
||
2538 | #else /* PNG_SLOW_PAETH */ |
||
2539 | p = a + b - c; |
||
2540 | pa = abs(p - a); |
||
2541 | pb = abs(p - b); |
||
2542 | pc = abs(p - c); |
||
2543 | if (pa <= pb && pa <= pc) |
||
2544 | p = a; |
||
2545 | else if (pb <= pc) |
||
2546 | p = b; |
||
2547 | else |
||
2548 | p = c; |
||
2549 | #endif /* PNG_SLOW_PAETH */ |
||
2550 | |||
2551 | v = *dp++ = (png_byte)(((int)*rp++ - p) & 0xff); |
||
2552 | |||
2553 | sum += (v < 128) ? v : 256 - v; |
||
2554 | |||
2555 | if (sum > lmins) /* We are already worse, don't continue. */ |
||
2556 | break; |
||
2557 | } |
||
2558 | |||
2559 | #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) |
||
2560 | if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) |
||
2561 | { |
||
2562 | int j; |
||
2563 | png_uint_32 sumhi, sumlo; |
||
2564 | sumlo = sum & PNG_LOMASK; |
||
2565 | sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; |
||
2566 | |||
2567 | for (j = 0; j < num_p_filters; j++) |
||
2568 | { |
||
2569 | if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_PAETH) |
||
2570 | { |
||
2571 | sumlo = (sumlo * png_ptr->filter_weights[j]) >> |
||
2572 | PNG_WEIGHT_SHIFT; |
||
2573 | sumhi = (sumhi * png_ptr->filter_weights[j]) >> |
||
2574 | PNG_WEIGHT_SHIFT; |
||
2575 | } |
||
2576 | } |
||
2577 | |||
2578 | sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_PAETH]) >> |
||
2579 | PNG_COST_SHIFT; |
||
2580 | sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_PAETH]) >> |
||
2581 | PNG_COST_SHIFT; |
||
2582 | |||
2583 | if (sumhi > PNG_HIMASK) |
||
2584 | sum = PNG_MAXSUM; |
||
2585 | else |
||
2586 | sum = (sumhi << PNG_HISHIFT) + sumlo; |
||
2587 | } |
||
2588 | #endif |
||
2589 | |||
2590 | if (sum < mins) |
||
2591 | { |
||
2592 | best_row = png_ptr->paeth_row; |
||
2593 | } |
||
2594 | } |
||
2595 | |||
2596 | /* Do the actual writing of the filtered row data from the chosen filter. */ |
||
2597 | |||
2598 | png_write_filtered_row(png_ptr, best_row); |
||
2599 | |||
2600 | #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) |
||
2601 | /* Save the type of filter we picked this time for future calculations */ |
||
2602 | if (png_ptr->num_prev_filters > 0) |
||
2603 | { |
||
2604 | int j; |
||
2605 | for (j = 1; j < num_p_filters; j++) |
||
2606 | { |
||
2607 | png_ptr->prev_filters[j] = png_ptr->prev_filters[j - 1]; |
||
2608 | } |
||
2609 | png_ptr->prev_filters[j] = best_row[0]; |
||
2610 | } |
||
2611 | #endif |
||
2612 | } |
||
2613 | |||
2614 | |||
2615 | /* Do the actual writing of a previously filtered row. */ |
||
2616 | void /* PRIVATE */ |
||
2617 | png_write_filtered_row(png_structp png_ptr, png_bytep filtered_row) |
||
2618 | { |
||
2619 | png_debug(1, "in png_write_filtered_row\n"); |
||
2620 | png_debug1(2, "filter = %d\n", filtered_row[0]); |
||
2621 | /* set up the zlib input buffer */ |
||
2622 | |||
2623 | png_ptr->zstream.next_in = filtered_row; |
||
2624 | png_ptr->zstream.avail_in = (uInt)png_ptr->row_info.rowbytes + 1; |
||
2625 | /* repeat until we have compressed all the data */ |
||
2626 | do |
||
2627 | { |
||
2628 | int ret; /* return of zlib */ |
||
2629 | |||
2630 | /* compress the data */ |
||
2631 | ret = deflate(&png_ptr->zstream, Z_NO_FLUSH); |
||
2632 | /* check for compression errors */ |
||
2633 | if (ret != Z_OK) |
||
2634 | { |
||
2635 | if (png_ptr->zstream.msg != NULL) |
||
2636 | png_error(png_ptr, png_ptr->zstream.msg); |
||
2637 | else |
||
2638 | png_error(png_ptr, "zlib error"); |
||
2639 | } |
||
2640 | |||
2641 | /* see if it is time to write another IDAT */ |
||
2642 | if (!(png_ptr->zstream.avail_out)) |
||
2643 | { |
||
2644 | /* write the IDAT and reset the zlib output buffer */ |
||
2645 | png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size); |
||
2646 | png_ptr->zstream.next_out = png_ptr->zbuf; |
||
2647 | png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; |
||
2648 | } |
||
2649 | /* repeat until all data has been compressed */ |
||
2650 | } while (png_ptr->zstream.avail_in); |
||
2651 | |||
2652 | /* swap the current and previous rows */ |
||
2653 | if (png_ptr->prev_row != NULL) |
||
2654 | { |
||
2655 | png_bytep tptr; |
||
2656 | |||
2657 | tptr = png_ptr->prev_row; |
||
2658 | png_ptr->prev_row = png_ptr->row_buf; |
||
2659 | png_ptr->row_buf = tptr; |
||
2660 | } |
||
2661 | |||
2662 | /* finish row - updates counters and flushes zlib if last row */ |
||
2663 | png_write_finish_row(png_ptr); |
||
2664 | |||
2665 | #if defined(PNG_WRITE_FLUSH_SUPPORTED) |
||
2666 | png_ptr->flush_rows++; |
||
2667 | |||
2668 | if (png_ptr->flush_dist > 0 && |
||
2669 | png_ptr->flush_rows >= png_ptr->flush_dist) |
||
2670 | { |
||
2671 | png_write_flush(png_ptr); |
||
2672 | } |
||
2673 | #endif |
||
2674 | } |
||
2675 | #endif /* PNG_WRITE_SUPPORTED */ |