/* pngwrite.c - general routines to write a PNG file
*
* libpng 1.2.5 - October 3, 2002
* For conditions of distribution and use, see copyright notice in png.h
* Copyright (c) 1998-2002 Glenn Randers-Pehrson
* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
* (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
*/
/* get internal access to png.h */
#define PNG_INTERNAL
#include "png.h"
#ifdef PNG_WRITE_SUPPORTED
/* Writes all the PNG information. This is the suggested way to use the
* library. If you have a new chunk to add, make a function to write it,
* and put it in the correct location here. If you want the chunk written
* after the image data, put it in png_write_end(). I strongly encourage
* you to supply a PNG_INFO_ flag, and check info_ptr->valid before writing
* the chunk, as that will keep the code from breaking if you want to just
* write a plain PNG file. If you have long comments, I suggest writing
* them in png_write_end(), and compressing them.
*/
void PNGAPI
png_write_info_before_PLTE
(png_structp png_ptr
, png_infop info_ptr
)
{
png_debug
(1, "in png_write_info_before_PLTE\n");
if (!(png_ptr
->mode
& PNG_WROTE_INFO_BEFORE_PLTE
))
{
png_write_sig
(png_ptr
); /* write PNG signature */
#if defined(PNG_MNG_FEATURES_SUPPORTED)
if((png_ptr
->mode
&PNG_HAVE_PNG_SIGNATURE
)&&(png_ptr
->mng_features_permitted
))
{
png_warning
(png_ptr
,"MNG features are not allowed in a PNG datastream\n");
png_ptr
->mng_features_permitted
=0;
}
#endif
/* write IHDR information. */
png_write_IHDR
(png_ptr
, info_ptr
->width
, info_ptr
->height
,
info_ptr
->bit_depth
, info_ptr
->color_type
, info_ptr
->compression_type
,
info_ptr
->filter_type
,
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
info_ptr
->interlace_type
);
#else
0);
#endif
/* the rest of these check to see if the valid field has the appropriate
flag set, and if it does, writes the chunk. */
#if defined(PNG_WRITE_gAMA_SUPPORTED)
if (info_ptr
->valid
& PNG_INFO_gAMA
)
{
# ifdef PNG_FLOATING_POINT_SUPPORTED
png_write_gAMA
(png_ptr
, info_ptr
->gamma
);
#else
#ifdef PNG_FIXED_POINT_SUPPORTED
png_write_gAMA_fixed
(png_ptr
, info_ptr
->int_gamma
);
# endif
#endif
}
#endif
#if defined(PNG_WRITE_sRGB_SUPPORTED)
if (info_ptr
->valid
& PNG_INFO_sRGB
)
png_write_sRGB
(png_ptr
, (int)info_ptr
->srgb_intent
);
#endif
#if defined(PNG_WRITE_iCCP_SUPPORTED)
if (info_ptr
->valid
& PNG_INFO_iCCP
)
png_write_iCCP
(png_ptr
, info_ptr
->iccp_name
, PNG_COMPRESSION_TYPE_BASE
,
info_ptr
->iccp_profile
, (int)info_ptr
->iccp_proflen
);
#endif
#if defined(PNG_WRITE_sBIT_SUPPORTED)
if (info_ptr
->valid
& PNG_INFO_sBIT
)
png_write_sBIT
(png_ptr
, &(info_ptr
->sig_bit
), info_ptr
->color_type
);
#endif
#if defined(PNG_WRITE_cHRM_SUPPORTED)
if (info_ptr
->valid
& PNG_INFO_cHRM
)
{
#ifdef PNG_FLOATING_POINT_SUPPORTED
png_write_cHRM
(png_ptr
,
info_ptr
->x_white
, info_ptr
->y_white
,
info_ptr
->x_red
, info_ptr
->y_red
,
info_ptr
->x_green
, info_ptr
->y_green
,
info_ptr
->x_blue
, info_ptr
->y_blue
);
#else
# ifdef PNG_FIXED_POINT_SUPPORTED
png_write_cHRM_fixed
(png_ptr
,
info_ptr
->int_x_white
, info_ptr
->int_y_white
,
info_ptr
->int_x_red
, info_ptr
->int_y_red
,
info_ptr
->int_x_green
, info_ptr
->int_y_green
,
info_ptr
->int_x_blue
, info_ptr
->int_y_blue
);
# endif
#endif
}
#endif
#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
if (info_ptr
->unknown_chunks_num
)
{
png_unknown_chunk
*up
;
png_debug
(5, "writing extra chunks\n");
for (up
= info_ptr
->unknown_chunks
;
up
< info_ptr
->unknown_chunks
+ info_ptr
->unknown_chunks_num
;
up
++)
{
int keep
=png_handle_as_unknown
(png_ptr
, up
->name
);
if (keep
!= HANDLE_CHUNK_NEVER
&&
up
->location
&& (!(up
->location
& PNG_HAVE_PLTE
)) &&
((up
->name
[3] & 0x20) || keep
== HANDLE_CHUNK_ALWAYS
||
(png_ptr
->flags
& PNG_FLAG_KEEP_UNSAFE_CHUNKS
)))
{
png_write_chunk
(png_ptr
, up
->name
, up
->data
, up
->size
);
}
}
}
#endif
png_ptr
->mode
|= PNG_WROTE_INFO_BEFORE_PLTE
;
}
}
void PNGAPI
png_write_info
(png_structp png_ptr
, png_infop info_ptr
)
{
#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
int i
;
#endif
png_debug
(1, "in png_write_info\n");
png_write_info_before_PLTE
(png_ptr
, info_ptr
);
if (info_ptr
->valid
& PNG_INFO_PLTE
)
png_write_PLTE
(png_ptr
, info_ptr
->palette
,
(png_uint_32
)info_ptr
->num_palette
);
else if (info_ptr
->color_type
== PNG_COLOR_TYPE_PALETTE
)
png_error
(png_ptr
, "Valid palette required for paletted images\n");
#if defined(PNG_WRITE_tRNS_SUPPORTED)
if (info_ptr
->valid
& PNG_INFO_tRNS
)
{
#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
/* invert the alpha channel (in tRNS) */
if ((png_ptr
->transformations
& PNG_INVERT_ALPHA
) &&
info_ptr
->color_type
== PNG_COLOR_TYPE_PALETTE
)
{
int j
;
for (j
=0; j
<(int)info_ptr
->num_trans
; j
++)
info_ptr
->trans
[j
] = (png_byte
)(255 - info_ptr
->trans
[j
]);
}
#endif
png_write_tRNS
(png_ptr
, info_ptr
->trans
, &(info_ptr
->trans_values
),
info_ptr
->num_trans
, info_ptr
->color_type
);
}
#endif
#if defined(PNG_WRITE_bKGD_SUPPORTED)
if (info_ptr
->valid
& PNG_INFO_bKGD
)
png_write_bKGD
(png_ptr
, &(info_ptr
->background
), info_ptr
->color_type
);
#endif
#if defined(PNG_WRITE_hIST_SUPPORTED)
if (info_ptr
->valid
& PNG_INFO_hIST
)
png_write_hIST
(png_ptr
, info_ptr
->hist
, info_ptr
->num_palette
);
#endif
#if defined(PNG_WRITE_oFFs_SUPPORTED)
if (info_ptr
->valid
& PNG_INFO_oFFs
)
png_write_oFFs
(png_ptr
, info_ptr
->x_offset
, info_ptr
->y_offset
,
info_ptr
->offset_unit_type
);
#endif
#if defined(PNG_WRITE_pCAL_SUPPORTED)
if (info_ptr
->valid
& PNG_INFO_pCAL
)
png_write_pCAL
(png_ptr
, info_ptr
->pcal_purpose
, info_ptr
->pcal_X0
,
info_ptr
->pcal_X1
, info_ptr
->pcal_type
, info_ptr
->pcal_nparams
,
info_ptr
->pcal_units
, info_ptr
->pcal_params
);
#endif
#if defined(PNG_WRITE_sCAL_SUPPORTED)
if (info_ptr
->valid
& PNG_INFO_sCAL
)
#if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
png_write_sCAL
(png_ptr
, (int)info_ptr
->scal_unit
,
info_ptr
->scal_pixel_width
, info_ptr
->scal_pixel_height
);
#else
#ifdef PNG_FIXED_POINT_SUPPORTED
png_write_sCAL_s
(png_ptr
, (int)info_ptr
->scal_unit
,
info_ptr
->scal_s_width
, info_ptr
->scal_s_height
);
#else
png_warning
(png_ptr
,
"png_write_sCAL not supported; sCAL chunk not written.\n");
#endif
#endif
#endif
#if defined(PNG_WRITE_pHYs_SUPPORTED)
if (info_ptr
->valid
& PNG_INFO_pHYs
)
png_write_pHYs
(png_ptr
, info_ptr
->x_pixels_per_unit
,
info_ptr
->y_pixels_per_unit
, info_ptr
->phys_unit_type
);
#endif
#if defined(PNG_WRITE_tIME_SUPPORTED)
if (info_ptr
->valid
& PNG_INFO_tIME
)
{
png_write_tIME
(png_ptr
, &(info_ptr
->mod_time
));
png_ptr
->mode
|= PNG_WROTE_tIME
;
}
#endif
#if defined(PNG_WRITE_sPLT_SUPPORTED)
if (info_ptr
->valid
& PNG_INFO_sPLT
)
for (i
= 0; i
< (int)info_ptr
->splt_palettes_num
; i
++)
png_write_sPLT
(png_ptr
, info_ptr
->splt_palettes
+ i
);
#endif
#if defined(PNG_WRITE_TEXT_SUPPORTED)
/* Check to see if we need to write text chunks */
for (i
= 0; i
< info_ptr
->num_text
; i
++)
{
png_debug2
(2, "Writing header text chunk %d, type %d\n", i
,
info_ptr
->text
[i
].
compression);
/* an internationalized chunk? */
if (info_ptr
->text
[i
].
compression > 0)
{
#if defined(PNG_WRITE_iTXt_SUPPORTED)
/* write international chunk */
png_write_iTXt
(png_ptr
,
info_ptr
->text
[i
].
compression,
info_ptr
->text
[i
].
key,
info_ptr
->text
[i
].
lang,
info_ptr
->text
[i
].
lang_key,
info_ptr
->text
[i
].
text);
#else
png_warning
(png_ptr
, "Unable to write international text\n");
#endif
/* Mark this chunk as written */
info_ptr
->text
[i
].
compression = PNG_TEXT_COMPRESSION_NONE_WR
;
}
/* If we want a compressed text chunk */
else if (info_ptr
->text
[i
].
compression == PNG_TEXT_COMPRESSION_zTXt
)
{
#if defined(PNG_WRITE_zTXt_SUPPORTED)
/* write compressed chunk */
png_write_zTXt
(png_ptr
, info_ptr
->text
[i
].
key,
info_ptr
->text
[i
].
text, 0,
info_ptr
->text
[i
].
compression);
#else
png_warning
(png_ptr
, "Unable to write compressed text\n");
#endif
/* Mark this chunk as written */
info_ptr
->text
[i
].
compression = PNG_TEXT_COMPRESSION_zTXt_WR
;
}
else if (info_ptr
->text
[i
].
compression == PNG_TEXT_COMPRESSION_NONE
)
{
#if defined(PNG_WRITE_tEXt_SUPPORTED)
/* write uncompressed chunk */
png_write_tEXt
(png_ptr
, info_ptr
->text
[i
].
key,
info_ptr
->text
[i
].
text,
0);
#else
png_warning
(png_ptr
, "Unable to write uncompressed text\n");
#endif
/* Mark this chunk as written */
info_ptr
->text
[i
].
compression = PNG_TEXT_COMPRESSION_NONE_WR
;
}
}
#endif
#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
if (info_ptr
->unknown_chunks_num
)
{
png_unknown_chunk
*up
;
png_debug
(5, "writing extra chunks\n");
for (up
= info_ptr
->unknown_chunks
;
up
< info_ptr
->unknown_chunks
+ info_ptr
->unknown_chunks_num
;
up
++)
{
int keep
=png_handle_as_unknown
(png_ptr
, up
->name
);
if (keep
!= HANDLE_CHUNK_NEVER
&&
up
->location
&& (up
->location
& PNG_HAVE_PLTE
) &&
!(up
->location
& PNG_HAVE_IDAT
) &&
((up
->name
[3] & 0x20) || keep
== HANDLE_CHUNK_ALWAYS
||
(png_ptr
->flags
& PNG_FLAG_KEEP_UNSAFE_CHUNKS
)))
{
png_write_chunk
(png_ptr
, up
->name
, up
->data
, up
->size
);
}
}
}
#endif
}
/* Writes the end of the PNG file. If you don't want to write comments or
* time information, you can pass NULL for info. If you already wrote these
* in png_write_info(), do not write them again here. If you have long
* comments, I suggest writing them here, and compressing them.
*/
void PNGAPI
png_write_end
(png_structp png_ptr
, png_infop info_ptr
)
{
png_debug
(1, "in png_write_end\n");
if (!(png_ptr
->mode
& PNG_HAVE_IDAT
))
png_error
(png_ptr
, "No IDATs written into file");
/* see if user wants us to write information chunks */
if (info_ptr
!= NULL
)
{
#if defined(PNG_WRITE_TEXT_SUPPORTED)
int i
; /* local index variable */
#endif
#if defined(PNG_WRITE_tIME_SUPPORTED)
/* check to see if user has supplied a time chunk */
if ((info_ptr
->valid
& PNG_INFO_tIME
) &&
!(png_ptr
->mode
& PNG_WROTE_tIME
))
png_write_tIME
(png_ptr
, &(info_ptr
->mod_time
));
#endif
#if defined(PNG_WRITE_TEXT_SUPPORTED)
/* loop through comment chunks */
for (i
= 0; i
< info_ptr
->num_text
; i
++)
{
png_debug2
(2, "Writing trailer text chunk %d, type %d\n", i
,
info_ptr
->text
[i
].
compression);
/* an internationalized chunk? */
if (info_ptr
->text
[i
].
compression > 0)
{
#if defined(PNG_WRITE_iTXt_SUPPORTED)
/* write international chunk */
png_write_iTXt
(png_ptr
,
info_ptr
->text
[i
].
compression,
info_ptr
->text
[i
].
key,
info_ptr
->text
[i
].
lang,
info_ptr
->text
[i
].
lang_key,
info_ptr
->text
[i
].
text);
#else
png_warning
(png_ptr
, "Unable to write international text\n");
#endif
/* Mark this chunk as written */
info_ptr
->text
[i
].
compression = PNG_TEXT_COMPRESSION_NONE_WR
;
}
else if (info_ptr
->text
[i
].
compression >= PNG_TEXT_COMPRESSION_zTXt
)
{
#if defined(PNG_WRITE_zTXt_SUPPORTED)
/* write compressed chunk */
png_write_zTXt
(png_ptr
, info_ptr
->text
[i
].
key,
info_ptr
->text
[i
].
text, 0,
info_ptr
->text
[i
].
compression);
#else
png_warning
(png_ptr
, "Unable to write compressed text\n");
#endif
/* Mark this chunk as written */
info_ptr
->text
[i
].
compression = PNG_TEXT_COMPRESSION_zTXt_WR
;
}
else if (info_ptr
->text
[i
].
compression == PNG_TEXT_COMPRESSION_NONE
)
{
#if defined(PNG_WRITE_tEXt_SUPPORTED)
/* write uncompressed chunk */
png_write_tEXt
(png_ptr
, info_ptr
->text
[i
].
key,
info_ptr
->text
[i
].
text, 0);
#else
png_warning
(png_ptr
, "Unable to write uncompressed text\n");
#endif
/* Mark this chunk as written */
info_ptr
->text
[i
].
compression = PNG_TEXT_COMPRESSION_NONE_WR
;
}
}
#endif
#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
if (info_ptr
->unknown_chunks_num
)
{
png_unknown_chunk
*up
;
png_debug
(5, "writing extra chunks\n");
for (up
= info_ptr
->unknown_chunks
;
up
< info_ptr
->unknown_chunks
+ info_ptr
->unknown_chunks_num
;
up
++)
{
int keep
=png_handle_as_unknown
(png_ptr
, up
->name
);
if (keep
!= HANDLE_CHUNK_NEVER
&&
up
->location
&& (up
->location
& PNG_AFTER_IDAT
) &&
((up
->name
[3] & 0x20) || keep
== HANDLE_CHUNK_ALWAYS
||
(png_ptr
->flags
& PNG_FLAG_KEEP_UNSAFE_CHUNKS
)))
{
png_write_chunk
(png_ptr
, up
->name
, up
->data
, up
->size
);
}
}
}
#endif
}
png_ptr
->mode
|= PNG_AFTER_IDAT
;
/* write end of PNG file */
png_write_IEND
(png_ptr
);
#if 0
/* This flush, added in libpng-1.0.8, causes some applications to crash
because they do not set png_ptr->output_flush_fn */
png_flush
(png_ptr
);
#endif
}
#if defined(PNG_WRITE_tIME_SUPPORTED)
#if !defined(_WIN32_WCE)
/* "time.h" functions are not supported on WindowsCE */
void PNGAPI
png_convert_from_struct_tm
(png_timep ptime
, struct tm FAR
* ttime
)
{
png_debug
(1, "in png_convert_from_struct_tm\n");
ptime
->year
= (png_uint_16
)(1900 + ttime
->tm_year
);
ptime
->month
= (png_byte
)(ttime
->tm_mon
+ 1);
ptime
->day
= (png_byte
)ttime
->tm_mday
;
ptime
->hour
= (png_byte
)ttime
->tm_hour
;
ptime
->minute
= (png_byte
)ttime
->tm_min
;
ptime
->second
= (png_byte
)ttime
->tm_sec
;
}
void PNGAPI
png_convert_from_time_t
(png_timep ptime
, time_t ttime
)
{
struct tm
*tbuf
;
png_debug
(1, "in png_convert_from_time_t\n");
tbuf
= gmtime(&ttime
);
png_convert_from_struct_tm
(ptime
, tbuf
);
}
#endif
#endif
/* Initialize png_ptr structure, and allocate any memory needed */
png_structp PNGAPI
png_create_write_struct
(png_const_charp user_png_ver
, png_voidp error_ptr
,
png_error_ptr error_fn
, png_error_ptr warn_fn
)
{
#ifdef PNG_USER_MEM_SUPPORTED
return (png_create_write_struct_2
(user_png_ver
, error_ptr
, error_fn
,
warn_fn
, png_voidp_NULL
, png_malloc_ptr_NULL
, png_free_ptr_NULL
));
}
/* Alternate initialize png_ptr structure, and allocate any memory needed */
png_structp PNGAPI
png_create_write_struct_2
(png_const_charp user_png_ver
, png_voidp error_ptr
,
png_error_ptr error_fn
, png_error_ptr warn_fn
, png_voidp mem_ptr
,
png_malloc_ptr malloc_fn
, png_free_ptr free_fn
)
{
#endif /* PNG_USER_MEM_SUPPORTED */
png_structp png_ptr
;
#ifdef PNG_SETJMP_SUPPORTED
#ifdef USE_FAR_KEYWORD
jmp_buf jmpbuf
;
#endif
#endif
int i
;
png_debug
(1, "in png_create_write_struct\n");
#ifdef PNG_USER_MEM_SUPPORTED
png_ptr
= (png_structp
)png_create_struct_2
(PNG_STRUCT_PNG
,
(png_malloc_ptr
)malloc_fn
, (png_voidp
)mem_ptr
);
#else
png_ptr
= (png_structp
)png_create_struct
(PNG_STRUCT_PNG
);
#endif /* PNG_USER_MEM_SUPPORTED */
if (png_ptr
== NULL
)
return (NULL
);
#if !defined(PNG_1_0_X)
#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
png_init_mmx_flags
(png_ptr
); /* 1.2.0 addition */
#endif
#endif /* PNG_1_0_X */
#ifdef PNG_SETJMP_SUPPORTED
#ifdef USE_FAR_KEYWORD
if (setjmp(jmpbuf
))
#else
if (setjmp(png_ptr
->jmpbuf
))
#endif
{
png_free
(png_ptr
, png_ptr
->zbuf
);
png_ptr
->zbuf
=NULL
;
png_destroy_struct
(png_ptr
);
return (NULL
);
}
#ifdef USE_FAR_KEYWORD
png_memcpy
(png_ptr
->jmpbuf
,jmpbuf
,sizeof(jmp_buf
));
#endif
#endif
#ifdef PNG_USER_MEM_SUPPORTED
png_set_mem_fn
(png_ptr
, mem_ptr
, malloc_fn
, free_fn
);
#endif /* PNG_USER_MEM_SUPPORTED */
png_set_error_fn
(png_ptr
, error_ptr
, error_fn
, warn_fn
);
i
=0;
do
{
if(user_png_ver
[i
] != png_libpng_ver
[i
])
png_ptr
->flags
|= PNG_FLAG_LIBRARY_MISMATCH
;
} while (png_libpng_ver
[i
++]);
if (png_ptr
->flags
& PNG_FLAG_LIBRARY_MISMATCH
)
{
/* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
* we must recompile any applications that use any older library version.
* For versions after libpng 1.0, we will be compatible, so we need
* only check the first digit.
*/
if (user_png_ver
== NULL
|| user_png_ver
[0] != png_libpng_ver
[0] ||
(user_png_ver
[0] == '1' && user_png_ver
[2] != png_libpng_ver
[2]) ||
(user_png_ver
[0] == '0' && user_png_ver
[2] < '9'))
{
#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
char msg
[80];
if (user_png_ver
)
{
sprintf(msg
, "Application was compiled with png.h from libpng-%.20s",
user_png_ver
);
png_warning
(png_ptr
, msg
);
}
sprintf(msg
, "Application is running with png.c from libpng-%.20s",
png_libpng_ver
);
png_warning
(png_ptr
, msg
);
#endif
#ifdef PNG_ERROR_NUMBERS_SUPPORTED
png_ptr
->flags
=0;
#endif
png_error
(png_ptr
,
"Incompatible libpng version in application and library");
}
}
/* initialize zbuf - compression buffer */
png_ptr
->zbuf_size
= PNG_ZBUF_SIZE
;
png_ptr
->zbuf
= (png_bytep
)png_malloc
(png_ptr
,
(png_uint_32
)png_ptr
->zbuf_size
);
png_set_write_fn
(png_ptr
, png_voidp_NULL
, png_rw_ptr_NULL
,
png_flush_ptr_NULL
);
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
png_set_filter_heuristics
(png_ptr
, PNG_FILTER_HEURISTIC_DEFAULT
,
1, png_doublep_NULL
, png_doublep_NULL
);
#endif
#ifdef PNG_SETJMP_SUPPORTED
/* Applications that neglect to set up their own setjmp() and then encounter
a png_error() will longjmp here. Since the jmpbuf is then meaningless we
abort instead of returning. */
#ifdef USE_FAR_KEYWORD
if (setjmp(jmpbuf
))
PNG_ABORT
();
png_memcpy
(png_ptr
->jmpbuf
,jmpbuf
,sizeof(jmp_buf
));
#else
if (setjmp(png_ptr
->jmpbuf
))
PNG_ABORT
();
#endif
#endif
return (png_ptr
);
}
/* Initialize png_ptr structure, and allocate any memory needed */
#undef png_write_init
void PNGAPI
png_write_init
(png_structp png_ptr
)
{
/* We only come here via pre-1.0.7-compiled applications */
png_write_init_2
(png_ptr
, "1.0.6 or earlier", 0, 0);
}
void PNGAPI
png_write_init_2
(png_structp png_ptr
, png_const_charp user_png_ver
,
png_size_t png_struct_size
, png_size_t png_info_size
)
{
/* We only come here via pre-1.0.12-compiled applications */
#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
if(sizeof(png_struct
) > png_struct_size
|| sizeof(png_info
) > png_info_size
)
{
char msg
[80];
png_ptr
->warning_fn
=NULL
;
if (user_png_ver
)
{
sprintf(msg
, "Application was compiled with png.h from libpng-%.20s",
user_png_ver
);
png_warning
(png_ptr
, msg
);
}
sprintf(msg
, "Application is running with png.c from libpng-%.20s",
png_libpng_ver
);
png_warning
(png_ptr
, msg
);
}
#endif
if(sizeof(png_struct
) > png_struct_size
)
{
png_ptr
->error_fn
=NULL
;
#ifdef PNG_ERROR_NUMBERS_SUPPORTED
png_ptr
->flags
=0;
#endif
png_error
(png_ptr
,
"The png struct allocated by the application for writing is too small.");
}
if(sizeof(png_info
) > png_info_size
)
{
png_ptr
->error_fn
=NULL
;
#ifdef PNG_ERROR_NUMBERS_SUPPORTED
png_ptr
->flags
=0;
#endif
png_error
(png_ptr
,
"The info struct allocated by the application for writing is too small.");
}
png_write_init_3
(&png_ptr
, user_png_ver
, png_struct_size
);
}
void PNGAPI
png_write_init_3
(png_structpp ptr_ptr
, png_const_charp user_png_ver
,
png_size_t png_struct_size
)
{
png_structp png_ptr
=*ptr_ptr
;
#ifdef PNG_SETJMP_SUPPORTED
jmp_buf tmp_jmp
; /* to save current jump buffer */
#endif
int i
= 0;
do
{
if (user_png_ver
[i
] != png_libpng_ver
[i
])
{
#ifdef PNG_LEGACY_SUPPORTED
png_ptr
->flags
|= PNG_FLAG_LIBRARY_MISMATCH
;
#else
png_ptr
->warning_fn
=NULL
;
png_warning
(png_ptr
,
"Application uses deprecated png_write_init() and should be recompiled.");
break;
#endif
}
} while (png_libpng_ver
[i
++]);
png_debug
(1, "in png_write_init_3\n");
#ifdef PNG_SETJMP_SUPPORTED
/* save jump buffer and error functions */
png_memcpy
(tmp_jmp
, png_ptr
->jmpbuf
, sizeof (jmp_buf
));
#endif
if (sizeof(png_struct
) > png_struct_size
)
{
png_destroy_struct
(png_ptr
);
png_ptr
= (png_structp
)png_create_struct
(PNG_STRUCT_PNG
);
*ptr_ptr
= png_ptr
;
}
/* reset all variables to 0 */
png_memset
(png_ptr
, 0, sizeof (png_struct
));
#if !defined(PNG_1_0_X)
#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
png_init_mmx_flags
(png_ptr
); /* 1.2.0 addition */
#endif
#endif /* PNG_1_0_X */
#ifdef PNG_SETJMP_SUPPORTED
/* restore jump buffer */
png_memcpy
(png_ptr
->jmpbuf
, tmp_jmp
, sizeof (jmp_buf
));
#endif
png_set_write_fn
(png_ptr
, png_voidp_NULL
, png_rw_ptr_NULL
,
png_flush_ptr_NULL
);
/* initialize zbuf - compression buffer */
png_ptr
->zbuf_size
= PNG_ZBUF_SIZE
;
png_ptr
->zbuf
= (png_bytep
)png_malloc
(png_ptr
,
(png_uint_32
)png_ptr
->zbuf_size
);
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
png_set_filter_heuristics
(png_ptr
, PNG_FILTER_HEURISTIC_DEFAULT
,
1, png_doublep_NULL
, png_doublep_NULL
);
#endif
}
/* Write a few rows of image data. If the image is interlaced,
* either you will have to write the 7 sub images, or, if you
* have called png_set_interlace_handling(), you will have to
* "write" the image seven times.
*/
void PNGAPI
png_write_rows
(png_structp png_ptr
, png_bytepp row
,
png_uint_32 num_rows
)
{
png_uint_32 i
; /* row counter */
png_bytepp rp
; /* row pointer */
png_debug
(1, "in png_write_rows\n");
/* loop through the rows */
for (i
= 0, rp
= row
; i
< num_rows
; i
++, rp
++)
{
png_write_row
(png_ptr
, *rp
);
}
}
/* Write the image. You only need to call this function once, even
* if you are writing an interlaced image.
*/
void PNGAPI
png_write_image
(png_structp png_ptr
, png_bytepp image
)
{
png_uint_32 i
; /* row index */
int pass
, num_pass
; /* pass variables */
png_bytepp rp
; /* points to current row */
png_debug
(1, "in png_write_image\n");
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
/* intialize interlace handling. If image is not interlaced,
this will set pass to 1 */
num_pass
= png_set_interlace_handling
(png_ptr
);
#else
num_pass
= 1;
#endif
/* loop through passes */
for (pass
= 0; pass
< num_pass
; pass
++)
{
/* loop through image */
for (i
= 0, rp
= image
; i
< png_ptr
->height
; i
++, rp
++)
{
png_write_row
(png_ptr
, *rp
);
}
}
}
/* called by user to write a row of image data */
void PNGAPI
png_write_row
(png_structp png_ptr
, png_bytep row
)
{
png_debug2
(1, "in png_write_row (row %ld, pass %d)\n",
png_ptr
->row_number
, png_ptr
->pass
);
/* initialize transformations and other stuff if first time */
if (png_ptr
->row_number
== 0 && png_ptr
->pass
== 0)
{
/* make sure we wrote the header info */
if (!(png_ptr
->mode
& PNG_WROTE_INFO_BEFORE_PLTE
))
png_error
(png_ptr
,
"png_write_info was never called before png_write_row.");
/* check for transforms that have been set but were defined out */
#if !defined(PNG_WRITE_INVERT_SUPPORTED) && defined(PNG_READ_INVERT_SUPPORTED)
if (png_ptr
->transformations
& PNG_INVERT_MONO
)
png_warning
(png_ptr
, "PNG_WRITE_INVERT_SUPPORTED is not defined.");
#endif
#if !defined(PNG_WRITE_FILLER_SUPPORTED) && defined(PNG_READ_FILLER_SUPPORTED)
if (png_ptr
->transformations
& PNG_FILLER
)
png_warning
(png_ptr
, "PNG_WRITE_FILLER_SUPPORTED is not defined.");
#endif
#if !defined(PNG_WRITE_PACKSWAP_SUPPORTED) && defined(PNG_READ_PACKSWAP_SUPPORTED)
if (png_ptr
->transformations
& PNG_PACKSWAP
)
png_warning
(png_ptr
, "PNG_WRITE_PACKSWAP_SUPPORTED is not defined.");
#endif
#if !defined(PNG_WRITE_PACK_SUPPORTED) && defined(PNG_READ_PACK_SUPPORTED)
if (png_ptr
->transformations
& PNG_PACK
)
png_warning
(png_ptr
, "PNG_WRITE_PACK_SUPPORTED is not defined.");
#endif
#if !defined(PNG_WRITE_SHIFT_SUPPORTED) && defined(PNG_READ_SHIFT_SUPPORTED)
if (png_ptr
->transformations
& PNG_SHIFT
)
png_warning
(png_ptr
, "PNG_WRITE_SHIFT_SUPPORTED is not defined.");
#endif
#if !defined(PNG_WRITE_BGR_SUPPORTED) && defined(PNG_READ_BGR_SUPPORTED)
if (png_ptr
->transformations
& PNG_BGR
)
png_warning
(png_ptr
, "PNG_WRITE_BGR_SUPPORTED is not defined.");
#endif
#if !defined(PNG_WRITE_SWAP_SUPPORTED) && defined(PNG_READ_SWAP_SUPPORTED)
if (png_ptr
->transformations
& PNG_SWAP_BYTES
)
png_warning
(png_ptr
, "PNG_WRITE_SWAP_SUPPORTED is not defined.");
#endif
png_write_start_row
(png_ptr
);
}
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
/* if interlaced and not interested in row, return */
if (png_ptr
->interlaced
&& (png_ptr
->transformations
& PNG_INTERLACE
))
{
switch (png_ptr
->pass
)
{
case 0:
if (png_ptr
->row_number
& 0x07)
{
png_write_finish_row
(png_ptr
);
return;
}
break;
case 1:
if ((png_ptr
->row_number
& 0x07) || png_ptr
->width
< 5)
{
png_write_finish_row
(png_ptr
);
return;
}
break;
case 2:
if ((png_ptr
->row_number
& 0x07) != 4)
{
png_write_finish_row
(png_ptr
);
return;
}
break;
case 3:
if ((png_ptr
->row_number
& 0x03) || png_ptr
->width
< 3)
{
png_write_finish_row
(png_ptr
);
return;
}
break;
case 4:
if ((png_ptr
->row_number
& 0x03) != 2)
{
png_write_finish_row
(png_ptr
);
return;
}
break;
case 5:
if ((png_ptr
->row_number
& 0x01) || png_ptr
->width
< 2)
{
png_write_finish_row
(png_ptr
);
return;
}
break;
case 6:
if (!(png_ptr
->row_number
& 0x01))
{
png_write_finish_row
(png_ptr
);
return;
}
break;
}
}
#endif
/* set up row info for transformations */
png_ptr
->row_info.
color_type = png_ptr
->color_type
;
png_ptr
->row_info.
width = png_ptr
->usr_width
;
png_ptr
->row_info.
channels = png_ptr
->usr_channels
;
png_ptr
->row_info.
bit_depth = png_ptr
->usr_bit_depth
;
png_ptr
->row_info.
pixel_depth = (png_byte
)(png_ptr
->row_info.
bit_depth *
png_ptr
->row_info.
channels);
png_ptr
->row_info.
rowbytes = ((png_ptr
->row_info.
width *
(png_uint_32
)png_ptr
->row_info.
pixel_depth + 7) >> 3);
png_debug1
(3, "row_info->color_type = %d\n", png_ptr
->row_info.
color_type);
png_debug1
(3, "row_info->width = %lu\n", png_ptr
->row_info.
width);
png_debug1
(3, "row_info->channels = %d\n", png_ptr
->row_info.
channels);
png_debug1
(3, "row_info->bit_depth = %d\n", png_ptr
->row_info.
bit_depth);
png_debug1
(3, "row_info->pixel_depth = %d\n", png_ptr
->row_info.
pixel_depth);
png_debug1
(3, "row_info->rowbytes = %lu\n", png_ptr
->row_info.
rowbytes);
/* Copy user's row into buffer, leaving room for filter byte. */
png_memcpy_check
(png_ptr
, png_ptr
->row_buf
+ 1, row
,
png_ptr
->row_info.
rowbytes);
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
/* handle interlacing */
if (png_ptr
->interlaced
&& png_ptr
->pass
< 6 &&
(png_ptr
->transformations
& PNG_INTERLACE
))
{
png_do_write_interlace
(&(png_ptr
->row_info
),
png_ptr
->row_buf
+ 1, png_ptr
->pass
);
/* this should always get caught above, but still ... */
if (!(png_ptr
->row_info.
width))
{
png_write_finish_row
(png_ptr
);
return;
}
}
#endif
/* handle other transformations */
if (png_ptr
->transformations
)
png_do_write_transformations
(png_ptr
);
#if defined(PNG_MNG_FEATURES_SUPPORTED)
/* Write filter_method 64 (intrapixel differencing) only if
* 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
* 2. Libpng did not write a PNG signature (this filter_method is only
* used in PNG datastreams that are embedded in MNG datastreams) and
* 3. The application called png_permit_mng_features with a mask that
* included PNG_FLAG_MNG_FILTER_64 and
* 4. The filter_method is 64 and
* 5. The color_type is RGB or RGBA
*/
if((png_ptr
->mng_features_permitted
& PNG_FLAG_MNG_FILTER_64
) &&
(png_ptr
->filter_type
== PNG_INTRAPIXEL_DIFFERENCING
))
{
/* Intrapixel differencing */
png_do_write_intrapixel
(&(png_ptr
->row_info
), png_ptr
->row_buf
+ 1);
}
#endif
/* Find a filter if necessary, filter the row and write it out. */
png_write_find_filter
(png_ptr
, &(png_ptr
->row_info
));
if (png_ptr
->write_row_fn
!= NULL
)
(*(png_ptr
->write_row_fn
))(png_ptr
, png_ptr
->row_number
, png_ptr
->pass
);
}
#if defined(PNG_WRITE_FLUSH_SUPPORTED)
/* Set the automatic flush interval or 0 to turn flushing off */
void PNGAPI
png_set_flush
(png_structp png_ptr
, int nrows
)
{
png_debug
(1, "in png_set_flush\n");
png_ptr
->flush_dist
= (nrows
< 0 ? 0 : nrows
);
}
/* flush the current output buffers now */
void PNGAPI
png_write_flush
(png_structp png_ptr
)
{
int wrote_IDAT
;
png_debug
(1, "in png_write_flush\n");
/* We have already written out all of the data */
if (png_ptr
->row_number
>= png_ptr
->num_rows
)
return;
do
{
int ret
;
/* compress the data */
ret
= deflate
(&png_ptr
->zstream
, Z_SYNC_FLUSH
);
wrote_IDAT
= 0;
/* check for compression errors */
if (ret
!= Z_OK
)
{
if (png_ptr
->zstream.
msg != NULL
)
png_error
(png_ptr
, png_ptr
->zstream.
msg);
else
png_error
(png_ptr
, "zlib error");
}
if (!(png_ptr
->zstream.
avail_out))
{
/* write the IDAT and reset the zlib output buffer */
png_write_IDAT
(png_ptr
, png_ptr
->zbuf
,
png_ptr
->zbuf_size
);
png_ptr
->zstream.
next_out = png_ptr
->zbuf
;
png_ptr
->zstream.
avail_out = (uInt
)png_ptr
->zbuf_size
;
wrote_IDAT
= 1;
}
} while(wrote_IDAT
== 1);
/* If there is any data left to be output, write it into a new IDAT */
if (png_ptr
->zbuf_size
!= png_ptr
->zstream.
avail_out)
{
/* write the IDAT and reset the zlib output buffer */
png_write_IDAT
(png_ptr
, png_ptr
->zbuf
,
png_ptr
->zbuf_size
- png_ptr
->zstream.
avail_out);
png_ptr
->zstream.
next_out = png_ptr
->zbuf
;
png_ptr
->zstream.
avail_out = (uInt
)png_ptr
->zbuf_size
;
}
png_ptr
->flush_rows
= 0;
png_flush
(png_ptr
);
}
#endif /* PNG_WRITE_FLUSH_SUPPORTED */
/* free all memory used by the write */
void PNGAPI
png_destroy_write_struct
(png_structpp png_ptr_ptr
, png_infopp info_ptr_ptr
)
{
png_structp png_ptr
= NULL
;
png_infop info_ptr
= NULL
;
#ifdef PNG_USER_MEM_SUPPORTED
png_free_ptr free_fn
= NULL
;
png_voidp mem_ptr
= NULL
;
#endif
png_debug
(1, "in png_destroy_write_struct\n");
if (png_ptr_ptr
!= NULL
)
{
png_ptr
= *png_ptr_ptr
;
#ifdef PNG_USER_MEM_SUPPORTED
free_fn
= png_ptr
->free_fn
;
mem_ptr
= png_ptr
->mem_ptr
;
#endif
}
if (info_ptr_ptr
!= NULL
)
info_ptr
= *info_ptr_ptr
;
if (info_ptr
!= NULL
)
{
png_free_data
(png_ptr
, info_ptr
, PNG_FREE_ALL
, -1);
#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
if (png_ptr
->num_chunk_list
)
{
png_free
(png_ptr
, png_ptr
->chunk_list
);
png_ptr
->chunk_list
=NULL
;
png_ptr
->num_chunk_list
=0;
}
#endif
#ifdef PNG_USER_MEM_SUPPORTED
png_destroy_struct_2
((png_voidp
)info_ptr
, (png_free_ptr
)free_fn
,
(png_voidp
)mem_ptr
);
#else
png_destroy_struct
((png_voidp
)info_ptr
);
#endif
*info_ptr_ptr
= NULL
;
}
if (png_ptr
!= NULL
)
{
png_write_destroy
(png_ptr
);
#ifdef PNG_USER_MEM_SUPPORTED
png_destroy_struct_2
((png_voidp
)png_ptr
, (png_free_ptr
)free_fn
,
(png_voidp
)mem_ptr
);
#else
png_destroy_struct
((png_voidp
)png_ptr
);
#endif
*png_ptr_ptr
= NULL
;
}
}
/* Free any memory used in png_ptr struct (old method) */
void /* PRIVATE */
png_write_destroy
(png_structp png_ptr
)
{
#ifdef PNG_SETJMP_SUPPORTED
jmp_buf tmp_jmp
; /* save jump buffer */
#endif
png_error_ptr error_fn
;
png_error_ptr warning_fn
;
png_voidp error_ptr
;
#ifdef PNG_USER_MEM_SUPPORTED
png_free_ptr free_fn
;
#endif
png_debug
(1, "in png_write_destroy\n");
/* free any memory zlib uses */
deflateEnd
(&png_ptr
->zstream
);
/* free our memory. png_free checks NULL for us. */
png_free
(png_ptr
, png_ptr
->zbuf
);
png_free
(png_ptr
, png_ptr
->row_buf
);
png_free
(png_ptr
, png_ptr
->prev_row
);
png_free
(png_ptr
, png_ptr
->sub_row
);
png_free
(png_ptr
, png_ptr
->up_row
);
png_free
(png_ptr
, png_ptr
->avg_row
);
png_free
(png_ptr
, png_ptr
->paeth_row
);
#if defined(PNG_TIME_RFC1123_SUPPORTED)
png_free
(png_ptr
, png_ptr
->time_buffer
);
#endif
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
png_free
(png_ptr
, png_ptr
->prev_filters
);
png_free
(png_ptr
, png_ptr
->filter_weights
);
png_free
(png_ptr
, png_ptr
->inv_filter_weights
);
png_free
(png_ptr
, png_ptr
->filter_costs
);
png_free
(png_ptr
, png_ptr
->inv_filter_costs
);
#endif
#ifdef PNG_SETJMP_SUPPORTED
/* reset structure */
png_memcpy
(tmp_jmp
, png_ptr
->jmpbuf
, sizeof (jmp_buf
));
#endif
error_fn
= png_ptr
->error_fn
;
warning_fn
= png_ptr
->warning_fn
;
error_ptr
= png_ptr
->error_ptr
;
#ifdef PNG_USER_MEM_SUPPORTED
free_fn
= png_ptr
->free_fn
;
#endif
png_memset
(png_ptr
, 0, sizeof (png_struct
));
png_ptr
->error_fn
= error_fn
;
png_ptr
->warning_fn
= warning_fn
;
png_ptr
->error_ptr
= error_ptr
;
#ifdef PNG_USER_MEM_SUPPORTED
png_ptr
->free_fn
= free_fn
;
#endif
#ifdef PNG_SETJMP_SUPPORTED
png_memcpy
(png_ptr
->jmpbuf
, tmp_jmp
, sizeof (jmp_buf
));
#endif
}
/* Allow the application to select one or more row filters to use. */
void PNGAPI
png_set_filter
(png_structp png_ptr
, int method
, int filters
)
{
png_debug
(1, "in png_set_filter\n");
#if defined(PNG_MNG_FEATURES_SUPPORTED)
if((png_ptr
->mng_features_permitted
& PNG_FLAG_MNG_FILTER_64
) &&
(method
== PNG_INTRAPIXEL_DIFFERENCING
))
method
= PNG_FILTER_TYPE_BASE
;
#endif
if (method
== PNG_FILTER_TYPE_BASE
)
{
switch (filters
& (PNG_ALL_FILTERS
| 0x07))
{
case 5:
case 6:
case 7: png_warning
(png_ptr
, "Unknown row filter for method 0");
case PNG_FILTER_VALUE_NONE
: png_ptr
->do_filter
=PNG_FILTER_NONE
; break;
case PNG_FILTER_VALUE_SUB
: png_ptr
->do_filter
=PNG_FILTER_SUB
; break;
case PNG_FILTER_VALUE_UP
: png_ptr
->do_filter
=PNG_FILTER_UP
; break;
case PNG_FILTER_VALUE_AVG
: png_ptr
->do_filter
=PNG_FILTER_AVG
; break;
case PNG_FILTER_VALUE_PAETH
: png_ptr
->do_filter
=PNG_FILTER_PAETH
;break;
default: png_ptr
->do_filter
= (png_byte
)filters
; break;
}
/* If we have allocated the row_buf, this means we have already started
* with the image and we should have allocated all of the filter buffers
* that have been selected. If prev_row isn't already allocated, then
* it is too late to start using the filters that need it, since we
* will be missing the data in the previous row. If an application
* wants to start and stop using particular filters during compression,
* it should start out with all of the filters, and then add and
* remove them after the start of compression.
*/
if (png_ptr
->row_buf
!= NULL
)
{
if ((png_ptr
->do_filter
& PNG_FILTER_SUB
) && png_ptr
->sub_row
== NULL
)
{
png_ptr
->sub_row
= (png_bytep
)png_malloc
(png_ptr
,
(png_ptr
->rowbytes
+ 1));
png_ptr
->sub_row
[0] = PNG_FILTER_VALUE_SUB
;
}
if ((png_ptr
->do_filter
& PNG_FILTER_UP
) && png_ptr
->up_row
== NULL
)
{
if (png_ptr
->prev_row
== NULL
)
{
png_warning
(png_ptr
, "Can't add Up filter after starting");
png_ptr
->do_filter
&= ~PNG_FILTER_UP
;
}
else
{
png_ptr
->up_row
= (png_bytep
)png_malloc
(png_ptr
,
(png_ptr
->rowbytes
+ 1));
png_ptr
->up_row
[0] = PNG_FILTER_VALUE_UP
;
}
}
if ((png_ptr
->do_filter
& PNG_FILTER_AVG
) && png_ptr
->avg_row
== NULL
)
{
if (png_ptr
->prev_row
== NULL
)
{
png_warning
(png_ptr
, "Can't add Average filter after starting");
png_ptr
->do_filter
&= ~PNG_FILTER_AVG
;
}
else
{
png_ptr
->avg_row
= (png_bytep
)png_malloc
(png_ptr
,
(png_ptr
->rowbytes
+ 1));
png_ptr
->avg_row
[0] = PNG_FILTER_VALUE_AVG
;
}
}
if ((png_ptr
->do_filter
& PNG_FILTER_PAETH
) &&
png_ptr
->paeth_row
== NULL
)
{
if (png_ptr
->prev_row
== NULL
)
{
png_warning
(png_ptr
, "Can't add Paeth filter after starting");
png_ptr
->do_filter
&= (png_byte
)(~PNG_FILTER_PAETH
);
}
else
{
png_ptr
->paeth_row
= (png_bytep
)png_malloc
(png_ptr
,
(png_ptr
->rowbytes
+ 1));
png_ptr
->paeth_row
[0] = PNG_FILTER_VALUE_PAETH
;
}
}
if (png_ptr
->do_filter
== PNG_NO_FILTERS
)
png_ptr
->do_filter
= PNG_FILTER_NONE
;
}
}
else
png_error
(png_ptr
, "Unknown custom filter method");
}
/* This allows us to influence the way in which libpng chooses the "best"
* filter for the current scanline. While the "minimum-sum-of-absolute-
* differences metric is relatively fast and effective, there is some
* question as to whether it can be improved upon by trying to keep the
* filtered data going to zlib more consistent, hopefully resulting in
* better compression.
*/
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* GRR 970116 */
void PNGAPI
png_set_filter_heuristics
(png_structp png_ptr
, int heuristic_method
,
int num_weights
, png_doublep filter_weights
,
png_doublep filter_costs
)
{
int i
;
png_debug
(1, "in png_set_filter_heuristics\n");
if (heuristic_method
>= PNG_FILTER_HEURISTIC_LAST
)
{
png_warning
(png_ptr
, "Unknown filter heuristic method");
return;
}
if (heuristic_method
== PNG_FILTER_HEURISTIC_DEFAULT
)
{
heuristic_method
= PNG_FILTER_HEURISTIC_UNWEIGHTED
;
}
if (num_weights
< 0 || filter_weights
== NULL
||
heuristic_method
== PNG_FILTER_HEURISTIC_UNWEIGHTED
)
{
num_weights
= 0;
}
png_ptr
->num_prev_filters
= (png_byte
)num_weights
;
png_ptr
->heuristic_method
= (png_byte
)heuristic_method
;
if (num_weights
> 0)
{
if (png_ptr
->prev_filters
== NULL
)
{
png_ptr
->prev_filters
= (png_bytep
)png_malloc
(png_ptr
,
(png_uint_32
)(sizeof(png_byte
) * num_weights
));
/* To make sure that the weighting starts out fairly */
for (i
= 0; i
< num_weights
; i
++)
{
png_ptr
->prev_filters
[i
] = 255;
}
}
if (png_ptr
->filter_weights
== NULL
)
{
png_ptr
->filter_weights
= (png_uint_16p
)png_malloc
(png_ptr
,
(png_uint_32
)(sizeof(png_uint_16
) * num_weights
));
png_ptr
->inv_filter_weights
= (png_uint_16p
)png_malloc
(png_ptr
,
(png_uint_32
)(sizeof(png_uint_16
) * num_weights
));
for (i
= 0; i
< num_weights
; i
++)
{
png_ptr
->inv_filter_weights
[i
] =
png_ptr
->filter_weights
[i
] = PNG_WEIGHT_FACTOR
;
}
}
for (i
= 0; i
< num_weights
; i
++)
{
if (filter_weights
[i
] < 0.0)
{
png_ptr
->inv_filter_weights
[i
] =
png_ptr
->filter_weights
[i
] = PNG_WEIGHT_FACTOR
;
}
else
{
png_ptr
->inv_filter_weights
[i
] =
(png_uint_16
)((double)PNG_WEIGHT_FACTOR
*filter_weights
[i
]+0.5);
png_ptr
->filter_weights
[i
] =
(png_uint_16
)((double)PNG_WEIGHT_FACTOR
/filter_weights
[i
]+0.5);
}
}
}
/* If, in the future, there are other filter methods, this would
* need to be based on png_ptr->filter.
*/
if (png_ptr
->filter_costs
== NULL
)
{
png_ptr
->filter_costs
= (png_uint_16p
)png_malloc
(png_ptr
,
(png_uint_32
)(sizeof(png_uint_16
) * PNG_FILTER_VALUE_LAST
));
png_ptr
->inv_filter_costs
= (png_uint_16p
)png_malloc
(png_ptr
,
(png_uint_32
)(sizeof(png_uint_16
) * PNG_FILTER_VALUE_LAST
));
for (i
= 0; i
< PNG_FILTER_VALUE_LAST
; i
++)
{
png_ptr
->inv_filter_costs
[i
] =
png_ptr
->filter_costs
[i
] = PNG_COST_FACTOR
;
}
}
/* Here is where we set the relative costs of the different filters. We
* should take the desired compression level into account when setting
* the costs, so that Paeth, for instance, has a high relative cost at low
* compression levels, while it has a lower relative cost at higher
* compression settings. The filter types are in order of increasing
* relative cost, so it would be possible to do this with an algorithm.
*/
for (i
= 0; i
< PNG_FILTER_VALUE_LAST
; i
++)
{
if (filter_costs
== NULL
|| filter_costs
[i
] < 0.0)
{
png_ptr
->inv_filter_costs
[i
] =
png_ptr
->filter_costs
[i
] = PNG_COST_FACTOR
;
}
else if (filter_costs
[i
] >= 1.0)
{
png_ptr
->inv_filter_costs
[i
] =
(png_uint_16
)((double)PNG_COST_FACTOR
/ filter_costs
[i
] + 0.5);
png_ptr
->filter_costs
[i
] =
(png_uint_16
)((double)PNG_COST_FACTOR
* filter_costs
[i
] + 0.5);
}
}
}
#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
void PNGAPI
png_set_compression_level
(png_structp png_ptr
, int level
)
{
png_debug
(1, "in png_set_compression_level\n");
png_ptr
->flags
|= PNG_FLAG_ZLIB_CUSTOM_LEVEL
;
png_ptr
->zlib_level
= level
;
}
void PNGAPI
png_set_compression_mem_level
(png_structp png_ptr
, int mem_level
)
{
png_debug
(1, "in png_set_compression_mem_level\n");
png_ptr
->flags
|= PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL
;
png_ptr
->zlib_mem_level
= mem_level
;
}
void PNGAPI
png_set_compression_strategy
(png_structp png_ptr
, int strategy
)
{
png_debug
(1, "in png_set_compression_strategy\n");
png_ptr
->flags
|= PNG_FLAG_ZLIB_CUSTOM_STRATEGY
;
png_ptr
->zlib_strategy
= strategy
;
}
void PNGAPI
png_set_compression_window_bits
(png_structp png_ptr
, int window_bits
)
{
if (window_bits
> 15)
png_warning
(png_ptr
, "Only compression windows <= 32k supported by PNG");
else if (window_bits
< 8)
png_warning
(png_ptr
, "Only compression windows >= 256 supported by PNG");
#ifndef WBITS_8_OK
/* avoid libpng bug with 256-byte windows */
if (window_bits
== 8)
{
png_warning
(png_ptr
, "Compression window is being reset to 512");
window_bits
=9;
}
#endif
png_ptr
->flags
|= PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS
;
png_ptr
->zlib_window_bits
= window_bits
;
}
void PNGAPI
png_set_compression_method
(png_structp png_ptr
, int method
)
{
png_debug
(1, "in png_set_compression_method\n");
if (method
!= 8)
png_warning
(png_ptr
, "Only compression method 8 is supported by PNG");
png_ptr
->flags
|= PNG_FLAG_ZLIB_CUSTOM_METHOD
;
png_ptr
->zlib_method
= method
;
}
void PNGAPI
png_set_write_status_fn
(png_structp png_ptr
, png_write_status_ptr write_row_fn
)
{
png_ptr
->write_row_fn
= write_row_fn
;
}
#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
void PNGAPI
png_set_write_user_transform_fn
(png_structp png_ptr
, png_user_transform_ptr
write_user_transform_fn
)
{
png_debug
(1, "in png_set_write_user_transform_fn\n");
png_ptr
->transformations
|= PNG_USER_TRANSFORM
;
png_ptr
->write_user_transform_fn
= write_user_transform_fn
;
}
#endif
#if defined(PNG_INFO_IMAGE_SUPPORTED)
void PNGAPI
png_write_png
(png_structp png_ptr
, png_infop info_ptr
,
int transforms
, voidp params
)
{
#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
/* invert the alpha channel from opacity to transparency */
if (transforms
& PNG_TRANSFORM_INVERT_ALPHA
)
png_set_invert_alpha
(png_ptr
);
#endif
/* Write the file header information. */
png_write_info
(png_ptr
, info_ptr
);
/* ------ these transformations don't touch the info structure ------- */
#if defined(PNG_WRITE_INVERT_SUPPORTED)
/* invert monochrome pixels */
if (transforms
& PNG_TRANSFORM_INVERT_MONO
)
png_set_invert_mono
(png_ptr
);
#endif
#if defined(PNG_WRITE_SHIFT_SUPPORTED)
/* Shift the pixels up to a legal bit depth and fill in
* as appropriate to correctly scale the image.
*/
if ((transforms
& PNG_TRANSFORM_SHIFT
)
&& (info_ptr
->valid
& PNG_INFO_sBIT
))
png_set_shift
(png_ptr
, &info_ptr
->sig_bit
);
#endif
#if defined(PNG_WRITE_PACK_SUPPORTED)
/* pack pixels into bytes */
if (transforms
& PNG_TRANSFORM_PACKING
)
png_set_packing
(png_ptr
);
#endif
#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
/* swap location of alpha bytes from ARGB to RGBA */
if (transforms
& PNG_TRANSFORM_SWAP_ALPHA
)
png_set_swap_alpha
(png_ptr
);
#endif
#if defined(PNG_WRITE_FILLER_SUPPORTED)
/* Get rid of filler (OR ALPHA) bytes, pack XRGB/RGBX/ARGB/RGBA into
* RGB (4 channels -> 3 channels). The second parameter is not used.
*/
if (transforms
& PNG_TRANSFORM_STRIP_FILLER
)
png_set_filler
(png_ptr
, 0, PNG_FILLER_BEFORE
);
#endif
#if defined(PNG_WRITE_BGR_SUPPORTED)
/* flip BGR pixels to RGB */
if (transforms
& PNG_TRANSFORM_BGR
)
png_set_bgr
(png_ptr
);
#endif
#if defined(PNG_WRITE_SWAP_SUPPORTED)
/* swap bytes of 16-bit files to most significant byte first */
if (transforms
& PNG_TRANSFORM_SWAP_ENDIAN
)
png_set_swap
(png_ptr
);
#endif
#if defined(PNG_WRITE_PACKSWAP_SUPPORTED)
/* swap bits of 1, 2, 4 bit packed pixel formats */
if (transforms
& PNG_TRANSFORM_PACKSWAP
)
png_set_packswap
(png_ptr
);
#endif
/* ----------------------- end of transformations ------------------- */
/* write the bits */
if (info_ptr
->valid
& PNG_INFO_IDAT
)
png_write_image
(png_ptr
, info_ptr
->row_pointers
);
/* It is REQUIRED to call this to finish writing the rest of the file */
png_write_end
(png_ptr
, info_ptr
);
if(transforms
== 0 || params
== NULL
)
/* quiet compiler warnings */ return;
}
#endif
#endif /* PNG_WRITE_SUPPORTED */