#include "pngpriv.h"
#ifdef PNG_WRITE_SUPPORTED
#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
void PNGAPI
png_save_uint_32(png_bytep buf, png_uint_32 i)
{
buf[0] = (png_byte)(i >> 24);
buf[1] = (png_byte)(i >> 16);
buf[2] = (png_byte)(i >> 8);
buf[3] = (png_byte)(i );
}
void PNGAPI
png_save_uint_16(png_bytep buf, unsigned int i)
{
buf[0] = (png_byte)(i >> 8);
buf[1] = (png_byte)(i );
}
#endif
void PNGAPI
png_write_sig(png_structrp png_ptr)
{
png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
#ifdef PNG_IO_STATE_SUPPORTED
png_ptr->io_state = PNG_IO_WRITING | PNG_IO_SIGNATURE;
#endif
png_write_data(png_ptr, &png_signature[png_ptr->sig_bytes],
(png_size_t)(8 - png_ptr->sig_bytes));
if (png_ptr->sig_bytes < 3)
png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE;
}
static void
png_write_chunk_header(png_structrp png_ptr, png_uint_32 chunk_name,
png_uint_32 length)
{
png_byte buf[8];
#if defined(PNG_DEBUG) && (PNG_DEBUG > 0)
PNG_CSTRING_FROM_CHUNK(buf, chunk_name);
png_debug2(0, "Writing %s chunk, length = %lu", buf, (unsigned long)length);
#endif
if (png_ptr == NULL)
return;
#ifdef PNG_IO_STATE_SUPPORTED
png_ptr->io_state = PNG_IO_WRITING | PNG_IO_CHUNK_HDR;
#endif
png_save_uint_32(buf, length);
png_save_uint_32(buf + 4, chunk_name);
png_write_data(png_ptr, buf, 8);
png_ptr->chunk_name = chunk_name;
png_reset_crc(png_ptr);
png_calculate_crc(png_ptr, buf + 4, 4);
#ifdef PNG_IO_STATE_SUPPORTED
png_ptr->io_state = PNG_IO_WRITING | PNG_IO_CHUNK_DATA;
#endif
}
void PNGAPI
png_write_chunk_start(png_structrp png_ptr, png_const_bytep chunk_string,
png_uint_32 length)
{
png_write_chunk_header(png_ptr, PNG_CHUNK_FROM_STRING(chunk_string), length);
}
void PNGAPI
png_write_chunk_data(png_structrp png_ptr, png_const_bytep data,
png_size_t length)
{
if (png_ptr == NULL)
return;
if (data != NULL && length > 0)
{
png_write_data(png_ptr, data, length);
png_calculate_crc(png_ptr, data, length);
}
}
void PNGAPI
png_write_chunk_end(png_structrp png_ptr)
{
png_byte buf[4];
if (png_ptr == NULL) return;
#ifdef PNG_IO_STATE_SUPPORTED
png_ptr->io_state = PNG_IO_WRITING | PNG_IO_CHUNK_CRC;
#endif
png_save_uint_32(buf, png_ptr->crc);
png_write_data(png_ptr, buf, (png_size_t)4);
}
static void
png_write_complete_chunk(png_structrp png_ptr, png_uint_32 chunk_name,
png_const_bytep data, png_size_t length)
{
if (png_ptr == NULL)
return;
if (length > PNG_UINT_31_MAX)
png_error(png_ptr, "length exceeds PNG maximum");
png_write_chunk_header(png_ptr, chunk_name, (png_uint_32)length);
png_write_chunk_data(png_ptr, data, length);
png_write_chunk_end(png_ptr);
}
void PNGAPI
png_write_chunk(png_structrp png_ptr, png_const_bytep chunk_string,
png_const_bytep data, png_size_t length)
{
png_write_complete_chunk(png_ptr, PNG_CHUNK_FROM_STRING(chunk_string), data,
length);
}
static png_alloc_size_t
png_image_size(png_structrp png_ptr)
{
png_uint_32 h = png_ptr->height;
if (png_ptr->rowbytes < 32768 && h < 32768)
{
if (png_ptr->interlaced != 0)
{
png_uint_32 w = png_ptr->width;
unsigned int pd = png_ptr->pixel_depth;
png_alloc_size_t cb_base;
int pass;
for (cb_base=0, pass=0; pass<=6; ++pass)
{
png_uint_32 pw = PNG_PASS_COLS(w, pass);
if (pw > 0)
cb_base += (PNG_ROWBYTES(pd, pw)+1) * PNG_PASS_ROWS(h, pass);
}
return cb_base;
}
else
return (png_ptr->rowbytes+1) * h;
}
else
return 0xffffffffU;
}
#ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
static void
optimize_cmf(png_bytep data, png_alloc_size_t data_size)
{
if (data_size <= 16384)
{
unsigned int z_cmf = data[0];
if ((z_cmf & 0x0f) == 8 && (z_cmf & 0xf0) <= 0x70)
{
unsigned int z_cinfo;
unsigned int half_z_window_size;
z_cinfo = z_cmf >> 4;
half_z_window_size = 1U << (z_cinfo + 7);
if (data_size <= half_z_window_size)
{
unsigned int tmp;
do
{
half_z_window_size >>= 1;
--z_cinfo;
}
while (z_cinfo > 0 && data_size <= half_z_window_size);
z_cmf = (z_cmf & 0x0f) | (z_cinfo << 4);
data[0] = (png_byte)z_cmf;
tmp = data[1] & 0xe0;
tmp += 0x1f - ((z_cmf << 8) + tmp) % 0x1f;
data[1] = (png_byte)tmp;
}
}
}
}
#endif
static int
png_deflate_claim(png_structrp png_ptr, png_uint_32 owner,
png_alloc_size_t data_size)
{
if (png_ptr->zowner != 0)
{
#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_ERROR_TEXT_SUPPORTED)
char msg[64];
PNG_STRING_FROM_CHUNK(msg, owner);
msg[4] = ':';
msg[5] = ' ';
PNG_STRING_FROM_CHUNK(msg+6, png_ptr->zowner);
(void)png_safecat(msg, (sizeof msg), 10, " using zstream");
#endif
#if PNG_RELEASE_BUILD
png_warning(png_ptr, msg);
if (png_ptr->zowner == png_IDAT)
{
png_ptr->zstream.msg = PNGZ_MSG_CAST("in use by IDAT");
return Z_STREAM_ERROR;
}
png_ptr->zowner = 0;
#else
png_error(png_ptr, msg);
#endif
}
{
int level = png_ptr->zlib_level;
int method = png_ptr->zlib_method;
int windowBits = png_ptr->zlib_window_bits;
int memLevel = png_ptr->zlib_mem_level;
int strategy;
int ret;
if (owner == png_IDAT)
{
if ((png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_STRATEGY) != 0)
strategy = png_ptr->zlib_strategy;
else if (png_ptr->do_filter != PNG_FILTER_NONE)
strategy = PNG_Z_DEFAULT_STRATEGY;
else
strategy = PNG_Z_DEFAULT_NOFILTER_STRATEGY;
}
else
{
#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
level = png_ptr->zlib_text_level;
method = png_ptr->zlib_text_method;
windowBits = png_ptr->zlib_text_window_bits;
memLevel = png_ptr->zlib_text_mem_level;
strategy = png_ptr->zlib_text_strategy;
#else
strategy = Z_DEFAULT_STRATEGY;
#endif
}
if (data_size <= 16384)
{
unsigned int half_window_size = 1U << (windowBits-1);
while (data_size + 262 <= half_window_size)
{
half_window_size >>= 1;
--windowBits;
}
}
if ((png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED) != 0 &&
(png_ptr->zlib_set_level != level ||
png_ptr->zlib_set_method != method ||
png_ptr->zlib_set_window_bits != windowBits ||
png_ptr->zlib_set_mem_level != memLevel ||
png_ptr->zlib_set_strategy != strategy))
{
if (deflateEnd(&png_ptr->zstream) != Z_OK)
png_warning(png_ptr, "deflateEnd failed (ignored)");
png_ptr->flags &= ~PNG_FLAG_ZSTREAM_INITIALIZED;
}
png_ptr->zstream.next_in = NULL;
png_ptr->zstream.avail_in = 0;
png_ptr->zstream.next_out = NULL;
png_ptr->zstream.avail_out = 0;
if ((png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED) != 0)
ret = deflateReset(&png_ptr->zstream);
else
{
ret = deflateInit2(&png_ptr->zstream, level, method, windowBits,
memLevel, strategy);
if (ret == Z_OK)
png_ptr->flags |= PNG_FLAG_ZSTREAM_INITIALIZED;
}
if (ret == Z_OK)
png_ptr->zowner = owner;
else
png_zstream_error(png_ptr, ret);
return ret;
}
}
void
png_free_buffer_list(png_structrp png_ptr, png_compression_bufferp *listp)
{
png_compression_bufferp list = *listp;
if (list != NULL)
{
*listp = NULL;
do
{
png_compression_bufferp next = list->next;
png_free(png_ptr, list);
list = next;
}
while (list != NULL);
}
}
#ifdef PNG_WRITE_COMPRESSED_TEXT_SUPPORTED
typedef struct
{
png_const_bytep input;
png_alloc_size_t input_len;
png_uint_32 output_len;
png_byte output[1024];
} compression_state;
static void
png_text_compress_init(compression_state *comp, png_const_bytep input,
png_alloc_size_t input_len)
{
comp->input = input;
comp->input_len = input_len;
comp->output_len = 0;
}
static int
png_text_compress(png_structrp png_ptr, png_uint_32 chunk_name,
compression_state *comp, png_uint_32 prefix_len)
{
int ret;
ret = png_deflate_claim(png_ptr, chunk_name, comp->input_len);
if (ret != Z_OK)
return ret;
{
png_compression_bufferp *end = &png_ptr->zbuffer_list;
png_alloc_size_t input_len = comp->input_len;
png_uint_32 output_len;
png_ptr->zstream.next_in = PNGZ_INPUT_CAST(comp->input);
png_ptr->zstream.avail_in = 0;
png_ptr->zstream.next_out = comp->output;
png_ptr->zstream.avail_out = (sizeof comp->output);
output_len = png_ptr->zstream.avail_out;
do
{
uInt avail_in = ZLIB_IO_MAX;
if (avail_in > input_len)
avail_in = (uInt)input_len;
input_len -= avail_in;
png_ptr->zstream.avail_in = avail_in;
if (png_ptr->zstream.avail_out == 0)
{
png_compression_buffer *next;
if (output_len + prefix_len > PNG_UINT_31_MAX)
{
ret = Z_MEM_ERROR;
break;
}
next = *end;
if (next == NULL)
{
next = png_voidcast(png_compression_bufferp, png_malloc_base
(png_ptr, PNG_COMPRESSION_BUFFER_SIZE(png_ptr)));
if (next == NULL)
{
ret = Z_MEM_ERROR;
break;
}
next->next = NULL;
*end = next;
}
png_ptr->zstream.next_out = next->output;
png_ptr->zstream.avail_out = png_ptr->zbuffer_size;
output_len += png_ptr->zstream.avail_out;
end = &next->next;
}
ret = deflate(&png_ptr->zstream,
input_len > 0 ? Z_NO_FLUSH : Z_FINISH);
input_len += png_ptr->zstream.avail_in;
png_ptr->zstream.avail_in = 0;
}
while (ret == Z_OK);
output_len -= png_ptr->zstream.avail_out;
png_ptr->zstream.avail_out = 0;
comp->output_len = output_len;
if (output_len + prefix_len >= PNG_UINT_31_MAX)
{
png_ptr->zstream.msg = PNGZ_MSG_CAST("compressed data too long");
ret = Z_MEM_ERROR;
}
else
png_zstream_error(png_ptr, ret);
png_ptr->zowner = 0;
if (ret == Z_STREAM_END && input_len == 0)
{
#ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
optimize_cmf(comp->output, comp->input_len);
#endif
return Z_OK;
}
else
return ret;
}
}
static void
png_write_compressed_data_out(png_structrp png_ptr, compression_state *comp)
{
png_uint_32 output_len = comp->output_len;
png_const_bytep output = comp->output;
png_uint_32 avail = (sizeof comp->output);
png_compression_buffer *next = png_ptr->zbuffer_list;
for (;;)
{
if (avail > output_len)
avail = output_len;
png_write_chunk_data(png_ptr, output, avail);
output_len -= avail;
if (output_len == 0 || next == NULL)
break;
avail = png_ptr->zbuffer_size;
output = next->output;
next = next->next;
}
if (output_len > 0)
png_error(png_ptr, "error writing ancillary chunked compressed data");
}
#endif
#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
static png_uint_32
png_check_keyword(png_structrp png_ptr, png_const_charp key, png_bytep new_key)
{
png_const_charp orig_key = key;
png_uint_32 key_len = 0;
int bad_character = 0;
int space = 1;
png_debug(1, "in png_check_keyword");
if (key == NULL)
{
*new_key = 0;
return 0;
}
while (*key && key_len < 79)
{
png_byte ch = (png_byte)*key++;
if ((ch > 32 && ch <= 126) || (ch >= 161 ))
*new_key++ = ch, ++key_len, space = 0;
else if (space == 0)
{
*new_key++ = 32, ++key_len, space = 1;
if (ch != 32)
bad_character = ch;
}
else if (bad_character == 0)
bad_character = ch;
}
if (key_len > 0 && space != 0)
{
--key_len, --new_key;
if (bad_character == 0)
bad_character = 32;
}
*new_key = 0;
if (key_len == 0)
return 0;
#ifdef PNG_WARNINGS_SUPPORTED
if (*key != 0)
png_warning(png_ptr, "keyword truncated");
else if (bad_character != 0)
{
PNG_WARNING_PARAMETERS(p)
png_warning_parameter(p, 1, orig_key);
png_warning_parameter_signed(p, 2, PNG_NUMBER_FORMAT_02x, bad_character);
png_formatted_warning(png_ptr, p, "keyword \"@1\": bad character '0x@2'");
}
#endif
return key_len;
}
#endif
void
png_write_IHDR(png_structrp png_ptr, png_uint_32 width, png_uint_32 height,
int bit_depth, int color_type, int compression_type, int filter_type,
int interlace_type)
{
png_byte buf[13];
png_debug(1, "in png_write_IHDR");
switch (color_type)
{
case PNG_COLOR_TYPE_GRAY:
switch (bit_depth)
{
case 1:
case 2:
case 4:
case 8:
#ifdef PNG_WRITE_16BIT_SUPPORTED
case 16:
#endif
png_ptr->channels = 1; break;
default:
png_error(png_ptr,
"Invalid bit depth for grayscale image");
}
break;
case PNG_COLOR_TYPE_RGB:
#ifdef PNG_WRITE_16BIT_SUPPORTED
if (bit_depth != 8 && bit_depth != 16)
#else
if (bit_depth != 8)
#endif
png_error(png_ptr, "Invalid bit depth for RGB image");
png_ptr->channels = 3;
break;
case PNG_COLOR_TYPE_PALETTE:
switch (bit_depth)
{
case 1:
case 2:
case 4:
case 8:
png_ptr->channels = 1;
break;
default:
png_error(png_ptr, "Invalid bit depth for paletted image");
}
break;
case PNG_COLOR_TYPE_GRAY_ALPHA:
if (bit_depth != 8 && bit_depth != 16)
png_error(png_ptr, "Invalid bit depth for grayscale+alpha image");
png_ptr->channels = 2;
break;
case PNG_COLOR_TYPE_RGB_ALPHA:
#ifdef PNG_WRITE_16BIT_SUPPORTED
if (bit_depth != 8 && bit_depth != 16)
#else
if (bit_depth != 8)
#endif
png_error(png_ptr, "Invalid bit depth for RGBA image");
png_ptr->channels = 4;
break;
default:
png_error(png_ptr, "Invalid image color type specified");
}
if (compression_type != PNG_COMPRESSION_TYPE_BASE)
{
png_warning(png_ptr, "Invalid compression type specified");
compression_type = PNG_COMPRESSION_TYPE_BASE;
}
if (
#ifdef PNG_MNG_FEATURES_SUPPORTED
!((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) != 0 &&
((png_ptr->mode & PNG_HAVE_PNG_SIGNATURE) == 0) &&
(color_type == PNG_COLOR_TYPE_RGB ||
color_type == PNG_COLOR_TYPE_RGB_ALPHA) &&
(filter_type == PNG_INTRAPIXEL_DIFFERENCING)) &&
#endif
filter_type != PNG_FILTER_TYPE_BASE)
{
png_warning(png_ptr, "Invalid filter type specified");
filter_type = PNG_FILTER_TYPE_BASE;
}
#ifdef PNG_WRITE_INTERLACING_SUPPORTED
if (interlace_type != PNG_INTERLACE_NONE &&
interlace_type != PNG_INTERLACE_ADAM7)
{
png_warning(png_ptr, "Invalid interlace type specified");
interlace_type = PNG_INTERLACE_ADAM7;
}
#else
interlace_type=PNG_INTERLACE_NONE;
#endif
png_ptr->bit_depth = (png_byte)bit_depth;
png_ptr->color_type = (png_byte)color_type;
png_ptr->interlaced = (png_byte)interlace_type;
#ifdef PNG_MNG_FEATURES_SUPPORTED
png_ptr->filter_type = (png_byte)filter_type;
#endif
png_ptr->compression_type = (png_byte)compression_type;
png_ptr->width = width;
png_ptr->height = height;
png_ptr->pixel_depth = (png_byte)(bit_depth * png_ptr->channels);
png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, width);
png_ptr->usr_width = png_ptr->width;
png_ptr->usr_bit_depth = png_ptr->bit_depth;
png_ptr->usr_channels = png_ptr->channels;
png_save_uint_32(buf, width);
png_save_uint_32(buf + 4, height);
buf[8] = (png_byte)bit_depth;
buf[9] = (png_byte)color_type;
buf[10] = (png_byte)compression_type;
buf[11] = (png_byte)filter_type;
buf[12] = (png_byte)interlace_type;
png_write_complete_chunk(png_ptr, png_IHDR, buf, (png_size_t)13);
if ((png_ptr->do_filter) == PNG_NO_FILTERS)
{
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE ||
png_ptr->bit_depth < 8)
png_ptr->do_filter = PNG_FILTER_NONE;
else
png_ptr->do_filter = PNG_ALL_FILTERS;
}
png_ptr->mode = PNG_HAVE_IHDR;
}
void
png_write_PLTE(png_structrp png_ptr, png_const_colorp palette,
png_uint_32 num_pal)
{
png_uint_32 max_palette_length, i;
png_const_colorp pal_ptr;
png_byte buf[3];
png_debug(1, "in png_write_PLTE");
max_palette_length = (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ?
(1 << png_ptr->bit_depth) : PNG_MAX_PALETTE_LENGTH;
if ((
#ifdef PNG_MNG_FEATURES_SUPPORTED
(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) == 0 &&
#endif
num_pal == 0) || num_pal > max_palette_length)
{
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
{
png_error(png_ptr, "Invalid number of colors in palette");
}
else
{
png_warning(png_ptr, "Invalid number of colors in palette");
return;
}
}
if ((png_ptr->color_type & PNG_COLOR_MASK_COLOR) == 0)
{
png_warning(png_ptr,
"Ignoring request to write a PLTE chunk in grayscale PNG");
return;
}
png_ptr->num_palette = (png_uint_16)num_pal;
png_debug1(3, "num_palette = %d", png_ptr->num_palette);
png_write_chunk_header(png_ptr, png_PLTE, (png_uint_32)(num_pal * 3));
#ifdef PNG_POINTER_INDEXING_SUPPORTED
for (i = 0, pal_ptr = palette; i < num_pal; i++, pal_ptr++)
{
buf[0] = pal_ptr->red;
buf[1] = pal_ptr->green;
buf[2] = pal_ptr->blue;
png_write_chunk_data(png_ptr, buf, (png_size_t)3);
}
#else
pal_ptr=palette;
for (i = 0; i < num_pal; i++)
{
buf[0] = pal_ptr[i].red;
buf[1] = pal_ptr[i].green;
buf[2] = pal_ptr[i].blue;
png_write_chunk_data(png_ptr, buf, (png_size_t)3);
}
#endif
png_write_chunk_end(png_ptr);
png_ptr->mode |= PNG_HAVE_PLTE;
}
void
png_compress_IDAT(png_structrp png_ptr, png_const_bytep input,
png_alloc_size_t input_len, int flush)
{
if (png_ptr->zowner != png_IDAT)
{
if (png_ptr->zbuffer_list == NULL)
{
png_ptr->zbuffer_list = png_voidcast(png_compression_bufferp,
png_malloc(png_ptr, PNG_COMPRESSION_BUFFER_SIZE(png_ptr)));
png_ptr->zbuffer_list->next = NULL;
}
else
png_free_buffer_list(png_ptr, &png_ptr->zbuffer_list->next);
if (png_deflate_claim(png_ptr, png_IDAT, png_image_size(png_ptr)) != Z_OK)
png_error(png_ptr, png_ptr->zstream.msg);
png_ptr->zstream.next_out = png_ptr->zbuffer_list->output;
png_ptr->zstream.avail_out = png_ptr->zbuffer_size;
}
png_ptr->zstream.next_in = PNGZ_INPUT_CAST(input);
png_ptr->zstream.avail_in = 0;
for (;;)
{
int ret;
uInt avail = ZLIB_IO_MAX;
if (avail > input_len)
avail = (uInt)input_len;
png_ptr->zstream.avail_in = avail;
input_len -= avail;
ret = deflate(&png_ptr->zstream, input_len > 0 ? Z_NO_FLUSH : flush);
input_len += png_ptr->zstream.avail_in;
png_ptr->zstream.avail_in = 0;
if (png_ptr->zstream.avail_out == 0)
{
png_bytep data = png_ptr->zbuffer_list->output;
uInt size = png_ptr->zbuffer_size;
#ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
if ((png_ptr->mode & PNG_HAVE_IDAT) == 0 &&
png_ptr->compression_type == PNG_COMPRESSION_TYPE_BASE)
optimize_cmf(data, png_image_size(png_ptr));
#endif
png_write_complete_chunk(png_ptr, png_IDAT, data, size);
png_ptr->mode |= PNG_HAVE_IDAT;
png_ptr->zstream.next_out = data;
png_ptr->zstream.avail_out = size;
if (ret == Z_OK && flush != Z_NO_FLUSH)
continue;
}
if (ret == Z_OK)
{
if (input_len == 0)
{
if (flush == Z_FINISH)
png_error(png_ptr, "Z_OK on Z_FINISH with output space");
return;
}
}
else if (ret == Z_STREAM_END && flush == Z_FINISH)
{
png_bytep data = png_ptr->zbuffer_list->output;
uInt size = png_ptr->zbuffer_size - png_ptr->zstream.avail_out;
#ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
if ((png_ptr->mode & PNG_HAVE_IDAT) == 0 &&
png_ptr->compression_type == PNG_COMPRESSION_TYPE_BASE)
optimize_cmf(data, png_image_size(png_ptr));
#endif
png_write_complete_chunk(png_ptr, png_IDAT, data, size);
png_ptr->zstream.avail_out = 0;
png_ptr->zstream.next_out = NULL;
png_ptr->mode |= PNG_HAVE_IDAT | PNG_AFTER_IDAT;
png_ptr->zowner = 0;
return;
}
else
{
png_zstream_error(png_ptr, ret);
png_error(png_ptr, png_ptr->zstream.msg);
}
}
}
void
png_write_IEND(png_structrp png_ptr)
{
png_debug(1, "in png_write_IEND");
png_write_complete_chunk(png_ptr, png_IEND, NULL, (png_size_t)0);
png_ptr->mode |= PNG_HAVE_IEND;
}
#ifdef PNG_WRITE_gAMA_SUPPORTED
void
png_write_gAMA_fixed(png_structrp png_ptr, png_fixed_point file_gamma)
{
png_byte buf[4];
png_debug(1, "in png_write_gAMA");
png_save_uint_32(buf, (png_uint_32)file_gamma);
png_write_complete_chunk(png_ptr, png_gAMA, buf, (png_size_t)4);
}
#endif
#ifdef PNG_WRITE_sRGB_SUPPORTED
void
png_write_sRGB(png_structrp png_ptr, int srgb_intent)
{
png_byte buf[1];
png_debug(1, "in png_write_sRGB");
if (srgb_intent >= PNG_sRGB_INTENT_LAST)
png_warning(png_ptr,
"Invalid sRGB rendering intent specified");
buf[0]=(png_byte)srgb_intent;
png_write_complete_chunk(png_ptr, png_sRGB, buf, (png_size_t)1);
}
#endif
#ifdef PNG_WRITE_iCCP_SUPPORTED
void
png_write_iCCP(png_structrp png_ptr, png_const_charp name,
png_const_bytep profile)
{
png_uint_32 name_len;
png_uint_32 profile_len;
png_byte new_name[81];
compression_state comp;
png_uint_32 temp;
png_debug(1, "in png_write_iCCP");
if (profile == NULL)
png_error(png_ptr, "No profile for iCCP chunk");
profile_len = png_get_uint_32(profile);
if (profile_len < 132)
png_error(png_ptr, "ICC profile too short");
temp = (png_uint_32) (*(profile+8));
if (temp > 3 && (profile_len & 0x03))
png_error(png_ptr, "ICC profile length invalid (not a multiple of 4)");
{
png_uint_32 embedded_profile_len = png_get_uint_32(profile);
if (profile_len != embedded_profile_len)
png_error(png_ptr, "Profile length does not match profile");
}
name_len = png_check_keyword(png_ptr, name, new_name);
if (name_len == 0)
png_error(png_ptr, "iCCP: invalid keyword");
new_name[++name_len] = PNG_COMPRESSION_TYPE_BASE;
++name_len;
png_text_compress_init(&comp, profile, profile_len);
if (png_text_compress(png_ptr, png_iCCP, &comp, name_len) != Z_OK)
png_error(png_ptr, png_ptr->zstream.msg);
png_write_chunk_header(png_ptr, png_iCCP, name_len + comp.output_len);
png_write_chunk_data(png_ptr, new_name, name_len);
png_write_compressed_data_out(png_ptr, &comp);
png_write_chunk_end(png_ptr);
}
#endif
#ifdef PNG_WRITE_sPLT_SUPPORTED
void
png_write_sPLT(png_structrp png_ptr, png_const_sPLT_tp spalette)
{
png_uint_32 name_len;
png_byte new_name[80];
png_byte entrybuf[10];
png_size_t entry_size = (spalette->depth == 8 ? 6 : 10);
png_size_t palette_size = entry_size * spalette->nentries;
png_sPLT_entryp ep;
#ifndef PNG_POINTER_INDEXING_SUPPORTED
int i;
#endif
png_debug(1, "in png_write_sPLT");
name_len = png_check_keyword(png_ptr, spalette->name, new_name);
if (name_len == 0)
png_error(png_ptr, "sPLT: invalid keyword");
png_write_chunk_header(png_ptr, png_sPLT,
(png_uint_32)(name_len + 2 + palette_size));
png_write_chunk_data(png_ptr, (png_bytep)new_name,
(png_size_t)(name_len + 1));
png_write_chunk_data(png_ptr, &spalette->depth, (png_size_t)1);
#ifdef PNG_POINTER_INDEXING_SUPPORTED
for (ep = spalette->entries; ep<spalette->entries + spalette->nentries; ep++)
{
if (spalette->depth == 8)
{
entrybuf[0] = (png_byte)ep->red;
entrybuf[1] = (png_byte)ep->green;
entrybuf[2] = (png_byte)ep->blue;
entrybuf[3] = (png_byte)ep->alpha;
png_save_uint_16(entrybuf + 4, ep->frequency);
}
else
{
png_save_uint_16(entrybuf + 0, ep->red);
png_save_uint_16(entrybuf + 2, ep->green);
png_save_uint_16(entrybuf + 4, ep->blue);
png_save_uint_16(entrybuf + 6, ep->alpha);
png_save_uint_16(entrybuf + 8, ep->frequency);
}
png_write_chunk_data(png_ptr, entrybuf, entry_size);
}
#else
ep=spalette->entries;
for (i = 0; i>spalette->nentries; i++)
{
if (spalette->depth == 8)
{
entrybuf[0] = (png_byte)ep[i].red;
entrybuf[1] = (png_byte)ep[i].green;
entrybuf[2] = (png_byte)ep[i].blue;
entrybuf[3] = (png_byte)ep[i].alpha;
png_save_uint_16(entrybuf + 4, ep[i].frequency);
}
else
{
png_save_uint_16(entrybuf + 0, ep[i].red);
png_save_uint_16(entrybuf + 2, ep[i].green);
png_save_uint_16(entrybuf + 4, ep[i].blue);
png_save_uint_16(entrybuf + 6, ep[i].alpha);
png_save_uint_16(entrybuf + 8, ep[i].frequency);
}
png_write_chunk_data(png_ptr, entrybuf, entry_size);
}
#endif
png_write_chunk_end(png_ptr);
}
#endif
#ifdef PNG_WRITE_sBIT_SUPPORTED
void
png_write_sBIT(png_structrp png_ptr, png_const_color_8p sbit, int color_type)
{
png_byte buf[4];
png_size_t size;
png_debug(1, "in png_write_sBIT");
if ((color_type & PNG_COLOR_MASK_COLOR) != 0)
{
png_byte maxbits;
maxbits = (png_byte)(color_type==PNG_COLOR_TYPE_PALETTE ? 8 :
png_ptr->usr_bit_depth);
if (sbit->red == 0 || sbit->red > maxbits ||
sbit->green == 0 || sbit->green > maxbits ||
sbit->blue == 0 || sbit->blue > maxbits)
{
png_warning(png_ptr, "Invalid sBIT depth specified");
return;
}
buf[0] = sbit->red;
buf[1] = sbit->green;
buf[2] = sbit->blue;
size = 3;
}
else
{
if (sbit->gray == 0 || sbit->gray > png_ptr->usr_bit_depth)
{
png_warning(png_ptr, "Invalid sBIT depth specified");
return;
}
buf[0] = sbit->gray;
size = 1;
}
if ((color_type & PNG_COLOR_MASK_ALPHA) != 0)
{
if (sbit->alpha == 0 || sbit->alpha > png_ptr->usr_bit_depth)
{
png_warning(png_ptr, "Invalid sBIT depth specified");
return;
}
buf[size++] = sbit->alpha;
}
png_write_complete_chunk(png_ptr, png_sBIT, buf, size);
}
#endif
#ifdef PNG_WRITE_cHRM_SUPPORTED
void
png_write_cHRM_fixed(png_structrp png_ptr, const png_xy *xy)
{
png_byte buf[32];
png_debug(1, "in png_write_cHRM");
png_save_int_32(buf, xy->whitex);
png_save_int_32(buf + 4, xy->whitey);
png_save_int_32(buf + 8, xy->redx);
png_save_int_32(buf + 12, xy->redy);
png_save_int_32(buf + 16, xy->greenx);
png_save_int_32(buf + 20, xy->greeny);
png_save_int_32(buf + 24, xy->bluex);
png_save_int_32(buf + 28, xy->bluey);
png_write_complete_chunk(png_ptr, png_cHRM, buf, 32);
}
#endif
#ifdef PNG_WRITE_tRNS_SUPPORTED
void
png_write_tRNS(png_structrp png_ptr, png_const_bytep trans_alpha,
png_const_color_16p tran, int num_trans, int color_type)
{
png_byte buf[6];
png_debug(1, "in png_write_tRNS");
if (color_type == PNG_COLOR_TYPE_PALETTE)
{
if (num_trans <= 0 || num_trans > (int)png_ptr->num_palette)
{
png_app_warning(png_ptr,
"Invalid number of transparent colors specified");
return;
}
png_write_complete_chunk(png_ptr, png_tRNS, trans_alpha,
(png_size_t)num_trans);
}
else if (color_type == PNG_COLOR_TYPE_GRAY)
{
if (tran->gray >= (1 << png_ptr->bit_depth))
{
png_app_warning(png_ptr,
"Ignoring attempt to write tRNS chunk out-of-range for bit_depth");
return;
}
png_save_uint_16(buf, tran->gray);
png_write_complete_chunk(png_ptr, png_tRNS, buf, (png_size_t)2);
}
else if (color_type == PNG_COLOR_TYPE_RGB)
{
png_save_uint_16(buf, tran->red);
png_save_uint_16(buf + 2, tran->green);
png_save_uint_16(buf + 4, tran->blue);
#ifdef PNG_WRITE_16BIT_SUPPORTED
if (png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4]) != 0)
#else
if ((buf[0] | buf[2] | buf[4]) != 0)
#endif
{
png_app_warning(png_ptr,
"Ignoring attempt to write 16-bit tRNS chunk when bit_depth is 8");
return;
}
png_write_complete_chunk(png_ptr, png_tRNS, buf, (png_size_t)6);
}
else
{
png_app_warning(png_ptr, "Can't write tRNS with an alpha channel");
}
}
#endif
#ifdef PNG_WRITE_bKGD_SUPPORTED
void
png_write_bKGD(png_structrp png_ptr, png_const_color_16p back, int color_type)
{
png_byte buf[6];
png_debug(1, "in png_write_bKGD");
if (color_type == PNG_COLOR_TYPE_PALETTE)
{
if (
#ifdef PNG_MNG_FEATURES_SUPPORTED
(png_ptr->num_palette != 0 ||
(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) == 0) &&
#endif
back->index >= png_ptr->num_palette)
{
png_warning(png_ptr, "Invalid background palette index");
return;
}
buf[0] = back->index;
png_write_complete_chunk(png_ptr, png_bKGD, buf, (png_size_t)1);
}
else if ((color_type & PNG_COLOR_MASK_COLOR) != 0)
{
png_save_uint_16(buf, back->red);
png_save_uint_16(buf + 2, back->green);
png_save_uint_16(buf + 4, back->blue);
#ifdef PNG_WRITE_16BIT_SUPPORTED
if (png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4]) != 0)
#else
if ((buf[0] | buf[2] | buf[4]) != 0)
#endif
{
png_warning(png_ptr,
"Ignoring attempt to write 16-bit bKGD chunk when bit_depth is 8");
return;
}
png_write_complete_chunk(png_ptr, png_bKGD, buf, (png_size_t)6);
}
else
{
if (back->gray >= (1 << png_ptr->bit_depth))
{
png_warning(png_ptr,
"Ignoring attempt to write bKGD chunk out-of-range for bit_depth");
return;
}
png_save_uint_16(buf, back->gray);
png_write_complete_chunk(png_ptr, png_bKGD, buf, (png_size_t)2);
}
}
#endif
#ifdef PNG_WRITE_hIST_SUPPORTED
void
png_write_hIST(png_structrp png_ptr, png_const_uint_16p hist, int num_hist)
{
int i;
png_byte buf[3];
png_debug(1, "in png_write_hIST");
if (num_hist > (int)png_ptr->num_palette)
{
png_debug2(3, "num_hist = %d, num_palette = %d", num_hist,
png_ptr->num_palette);
png_warning(png_ptr, "Invalid number of histogram entries specified");
return;
}
png_write_chunk_header(png_ptr, png_hIST, (png_uint_32)(num_hist * 2));
for (i = 0; i < num_hist; i++)
{
png_save_uint_16(buf, hist[i]);
png_write_chunk_data(png_ptr, buf, (png_size_t)2);
}
png_write_chunk_end(png_ptr);
}
#endif
#ifdef PNG_WRITE_tEXt_SUPPORTED
void
png_write_tEXt(png_structrp png_ptr, png_const_charp key, png_const_charp text,
png_size_t text_len)
{
png_uint_32 key_len;
png_byte new_key[80];
png_debug(1, "in png_write_tEXt");
key_len = png_check_keyword(png_ptr, key, new_key);
if (key_len == 0)
png_error(png_ptr, "tEXt: invalid keyword");
if (text == NULL || *text == '\0')
text_len = 0;
else
text_len = strlen(text);
if (text_len > PNG_UINT_31_MAX - (key_len+1))
png_error(png_ptr, "tEXt: text too long");
png_write_chunk_header(png_ptr, png_tEXt,
(png_uint_32)(key_len + text_len + 1));
png_write_chunk_data(png_ptr, new_key, key_len + 1);
if (text_len != 0)
png_write_chunk_data(png_ptr, (png_const_bytep)text, text_len);
png_write_chunk_end(png_ptr);
}
#endif
#ifdef PNG_WRITE_zTXt_SUPPORTED
void
png_write_zTXt(png_structrp png_ptr, png_const_charp key, png_const_charp text,
int compression)
{
png_uint_32 key_len;
png_byte new_key[81];
compression_state comp;
png_debug(1, "in png_write_zTXt");
if (compression == PNG_TEXT_COMPRESSION_NONE)
{
png_write_tEXt(png_ptr, key, text, 0);
return;
}
if (compression != PNG_TEXT_COMPRESSION_zTXt)
png_error(png_ptr, "zTXt: invalid compression type");
key_len = png_check_keyword(png_ptr, key, new_key);
if (key_len == 0)
png_error(png_ptr, "zTXt: invalid keyword");
new_key[++key_len] = PNG_COMPRESSION_TYPE_BASE;
++key_len;
png_text_compress_init(&comp, (png_const_bytep)text,
text == NULL ? 0 : strlen(text));
if (png_text_compress(png_ptr, png_zTXt, &comp, key_len) != Z_OK)
png_error(png_ptr, png_ptr->zstream.msg);
png_write_chunk_header(png_ptr, png_zTXt, key_len + comp.output_len);
png_write_chunk_data(png_ptr, new_key, key_len);
png_write_compressed_data_out(png_ptr, &comp);
png_write_chunk_end(png_ptr);
}
#endif
#ifdef PNG_WRITE_iTXt_SUPPORTED
void
png_write_iTXt(png_structrp png_ptr, int compression, png_const_charp key,
png_const_charp lang, png_const_charp lang_key, png_const_charp text)
{
png_uint_32 key_len, prefix_len;
png_size_t lang_len, lang_key_len;
png_byte new_key[82];
compression_state comp;
png_debug(1, "in png_write_iTXt");
key_len = png_check_keyword(png_ptr, key, new_key);
if (key_len == 0)
png_error(png_ptr, "iTXt: invalid keyword");
switch (compression)
{
case PNG_ITXT_COMPRESSION_NONE:
case PNG_TEXT_COMPRESSION_NONE:
compression = new_key[++key_len] = 0;
break;
case PNG_TEXT_COMPRESSION_zTXt:
case PNG_ITXT_COMPRESSION_zTXt:
compression = new_key[++key_len] = 1;
break;
default:
png_error(png_ptr, "iTXt: invalid compression");
}
new_key[++key_len] = PNG_COMPRESSION_TYPE_BASE;
++key_len;
if (lang == NULL) lang = "";
lang_len = strlen(lang)+1;
if (lang_key == NULL) lang_key = "";
lang_key_len = strlen(lang_key)+1;
if (text == NULL) text = "";
prefix_len = key_len;
if (lang_len > PNG_UINT_31_MAX-prefix_len)
prefix_len = PNG_UINT_31_MAX;
else
prefix_len = (png_uint_32)(prefix_len + lang_len);
if (lang_key_len > PNG_UINT_31_MAX-prefix_len)
prefix_len = PNG_UINT_31_MAX;
else
prefix_len = (png_uint_32)(prefix_len + lang_key_len);
png_text_compress_init(&comp, (png_const_bytep)text, strlen(text));
if (compression != 0)
{
if (png_text_compress(png_ptr, png_iTXt, &comp, prefix_len) != Z_OK)
png_error(png_ptr, png_ptr->zstream.msg);
}
else
{
if (comp.input_len > PNG_UINT_31_MAX-prefix_len)
png_error(png_ptr, "iTXt: uncompressed text too long");
comp.output_len = (png_uint_32)comp.input_len;
}
png_write_chunk_header(png_ptr, png_iTXt, comp.output_len + prefix_len);
png_write_chunk_data(png_ptr, new_key, key_len);
png_write_chunk_data(png_ptr, (png_const_bytep)lang, lang_len);
png_write_chunk_data(png_ptr, (png_const_bytep)lang_key, lang_key_len);
if (compression != 0)
png_write_compressed_data_out(png_ptr, &comp);
else
png_write_chunk_data(png_ptr, (png_const_bytep)text, comp.output_len);
png_write_chunk_end(png_ptr);
}
#endif
#ifdef PNG_WRITE_oFFs_SUPPORTED
void
png_write_oFFs(png_structrp png_ptr, png_int_32 x_offset, png_int_32 y_offset,
int unit_type)
{
png_byte buf[9];
png_debug(1, "in png_write_oFFs");
if (unit_type >= PNG_OFFSET_LAST)
png_warning(png_ptr, "Unrecognized unit type for oFFs chunk");
png_save_int_32(buf, x_offset);
png_save_int_32(buf + 4, y_offset);
buf[8] = (png_byte)unit_type;
png_write_complete_chunk(png_ptr, png_oFFs, buf, (png_size_t)9);
}
#endif
#ifdef PNG_WRITE_pCAL_SUPPORTED
void
png_write_pCAL(png_structrp png_ptr, png_charp purpose, png_int_32 X0,
png_int_32 X1, int type, int nparams, png_const_charp units,
png_charpp params)
{
png_uint_32 purpose_len;
png_size_t units_len, total_len;
png_size_tp params_len;
png_byte buf[10];
png_byte new_purpose[80];
int i;
png_debug1(1, "in png_write_pCAL (%d parameters)", nparams);
if (type >= PNG_EQUATION_LAST)
png_error(png_ptr, "Unrecognized equation type for pCAL chunk");
purpose_len = png_check_keyword(png_ptr, purpose, new_purpose);
if (purpose_len == 0)
png_error(png_ptr, "pCAL: invalid keyword");
++purpose_len;
png_debug1(3, "pCAL purpose length = %d", (int)purpose_len);
units_len = strlen(units) + (nparams == 0 ? 0 : 1);
png_debug1(3, "pCAL units length = %d", (int)units_len);
total_len = purpose_len + units_len + 10;
params_len = (png_size_tp)png_malloc(png_ptr,
(png_alloc_size_t)(nparams * (sizeof (png_size_t))));
for (i = 0; i < nparams; i++)
{
params_len[i] = strlen(params[i]) + (i == nparams - 1 ? 0 : 1);
png_debug2(3, "pCAL parameter %d length = %lu", i,
(unsigned long)params_len[i]);
total_len += params_len[i];
}
png_debug1(3, "pCAL total length = %d", (int)total_len);
png_write_chunk_header(png_ptr, png_pCAL, (png_uint_32)total_len);
png_write_chunk_data(png_ptr, new_purpose, purpose_len);
png_save_int_32(buf, X0);
png_save_int_32(buf + 4, X1);
buf[8] = (png_byte)type;
buf[9] = (png_byte)nparams;
png_write_chunk_data(png_ptr, buf, (png_size_t)10);
png_write_chunk_data(png_ptr, (png_const_bytep)units, (png_size_t)units_len);
for (i = 0; i < nparams; i++)
{
png_write_chunk_data(png_ptr, (png_const_bytep)params[i], params_len[i]);
}
png_free(png_ptr, params_len);
png_write_chunk_end(png_ptr);
}
#endif
#ifdef PNG_WRITE_sCAL_SUPPORTED
void
png_write_sCAL_s(png_structrp png_ptr, int unit, png_const_charp width,
png_const_charp height)
{
png_byte buf[64];
png_size_t wlen, hlen, total_len;
png_debug(1, "in png_write_sCAL_s");
wlen = strlen(width);
hlen = strlen(height);
total_len = wlen + hlen + 2;
if (total_len > 64)
{
png_warning(png_ptr, "Can't write sCAL (buffer too small)");
return;
}
buf[0] = (png_byte)unit;
memcpy(buf + 1, width, wlen + 1);
memcpy(buf + wlen + 2, height, hlen);
png_debug1(3, "sCAL total length = %u", (unsigned int)total_len);
png_write_complete_chunk(png_ptr, png_sCAL, buf, total_len);
}
#endif
#ifdef PNG_WRITE_pHYs_SUPPORTED
void
png_write_pHYs(png_structrp png_ptr, png_uint_32 x_pixels_per_unit,
png_uint_32 y_pixels_per_unit,
int unit_type)
{
png_byte buf[9];
png_debug(1, "in png_write_pHYs");
if (unit_type >= PNG_RESOLUTION_LAST)
png_warning(png_ptr, "Unrecognized unit type for pHYs chunk");
png_save_uint_32(buf, x_pixels_per_unit);
png_save_uint_32(buf + 4, y_pixels_per_unit);
buf[8] = (png_byte)unit_type;
png_write_complete_chunk(png_ptr, png_pHYs, buf, (png_size_t)9);
}
#endif
#ifdef PNG_WRITE_tIME_SUPPORTED
void
png_write_tIME(png_structrp png_ptr, png_const_timep mod_time)
{
png_byte buf[7];
png_debug(1, "in png_write_tIME");
if (mod_time->month > 12 || mod_time->month < 1 ||
mod_time->day > 31 || mod_time->day < 1 ||
mod_time->hour > 23 || mod_time->second > 60)
{
png_warning(png_ptr, "Invalid time specified for tIME chunk");
return;
}
png_save_uint_16(buf, mod_time->year);
buf[2] = mod_time->month;
buf[3] = mod_time->day;
buf[4] = mod_time->hour;
buf[5] = mod_time->minute;
buf[6] = mod_time->second;
png_write_complete_chunk(png_ptr, png_tIME, buf, (png_size_t)7);
}
#endif
void
png_write_start_row(png_structrp png_ptr)
{
#ifdef PNG_WRITE_INTERLACING_SUPPORTED
static PNG_CONST png_byte png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
static PNG_CONST png_byte png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
static PNG_CONST png_byte png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
static PNG_CONST png_byte png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
#endif
png_alloc_size_t buf_size;
int usr_pixel_depth;
#ifdef PNG_WRITE_FILTER_SUPPORTED
png_byte filters;
#endif
png_debug(1, "in png_write_start_row");
usr_pixel_depth = png_ptr->usr_channels * png_ptr->usr_bit_depth;
buf_size = PNG_ROWBYTES(usr_pixel_depth, png_ptr->width) + 1;
png_ptr->transformed_pixel_depth = png_ptr->pixel_depth;
png_ptr->maximum_pixel_depth = (png_byte)usr_pixel_depth;
png_ptr->row_buf = png_voidcast(png_bytep, png_malloc(png_ptr, buf_size));
png_ptr->row_buf[0] = PNG_FILTER_VALUE_NONE;
#ifdef PNG_WRITE_FILTER_SUPPORTED
filters = png_ptr->do_filter;
if (png_ptr->height == 1)
filters &= 0xff & ~(PNG_FILTER_UP|PNG_FILTER_AVG|PNG_FILTER_PAETH);
if (png_ptr->width == 1)
filters &= 0xff & ~(PNG_FILTER_SUB|PNG_FILTER_AVG|PNG_FILTER_PAETH);
if (filters == 0)
filters = PNG_FILTER_NONE;
png_ptr->do_filter = filters;
if (((filters & (PNG_FILTER_SUB | PNG_FILTER_UP | PNG_FILTER_AVG |
PNG_FILTER_PAETH)) != 0) && png_ptr->try_row == NULL)
{
int num_filters = 0;
png_ptr->try_row = png_voidcast(png_bytep, png_malloc(png_ptr, buf_size));
if (filters & PNG_FILTER_SUB)
num_filters++;
if (filters & PNG_FILTER_UP)
num_filters++;
if (filters & PNG_FILTER_AVG)
num_filters++;
if (filters & PNG_FILTER_PAETH)
num_filters++;
if (num_filters > 1)
png_ptr->tst_row = png_voidcast(png_bytep, png_malloc(png_ptr,
buf_size));
}
if ((filters & (PNG_FILTER_AVG | PNG_FILTER_UP | PNG_FILTER_PAETH)) != 0)
png_ptr->prev_row = png_voidcast(png_bytep,
png_calloc(png_ptr, buf_size));
#endif
#ifdef PNG_WRITE_INTERLACING_SUPPORTED
if (png_ptr->interlaced != 0)
{
if ((png_ptr->transformations & PNG_INTERLACE) == 0)
{
png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 -
png_pass_ystart[0]) / png_pass_yinc[0];
png_ptr->usr_width = (png_ptr->width + png_pass_inc[0] - 1 -
png_pass_start[0]) / png_pass_inc[0];
}
else
{
png_ptr->num_rows = png_ptr->height;
png_ptr->usr_width = png_ptr->width;
}
}
else
#endif
{
png_ptr->num_rows = png_ptr->height;
png_ptr->usr_width = png_ptr->width;
}
}
void
png_write_finish_row(png_structrp png_ptr)
{
#ifdef PNG_WRITE_INTERLACING_SUPPORTED
static PNG_CONST png_byte png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
static PNG_CONST png_byte png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
static PNG_CONST png_byte png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
static PNG_CONST png_byte png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
#endif
png_debug(1, "in png_write_finish_row");
png_ptr->row_number++;
if (png_ptr->row_number < png_ptr->num_rows)
return;
#ifdef PNG_WRITE_INTERLACING_SUPPORTED
if (png_ptr->interlaced != 0)
{
png_ptr->row_number = 0;
if ((png_ptr->transformations & PNG_INTERLACE) != 0)
{
png_ptr->pass++;
}
else
{
do
{
png_ptr->pass++;
if (png_ptr->pass >= 7)
break;
png_ptr->usr_width = (png_ptr->width +
png_pass_inc[png_ptr->pass] - 1 -
png_pass_start[png_ptr->pass]) /
png_pass_inc[png_ptr->pass];
png_ptr->num_rows = (png_ptr->height +
png_pass_yinc[png_ptr->pass] - 1 -
png_pass_ystart[png_ptr->pass]) /
png_pass_yinc[png_ptr->pass];
if ((png_ptr->transformations & PNG_INTERLACE) != 0)
break;
} while (png_ptr->usr_width == 0 || png_ptr->num_rows == 0);
}
if (png_ptr->pass < 7)
{
if (png_ptr->prev_row != NULL)
memset(png_ptr->prev_row, 0,
(png_size_t)(PNG_ROWBYTES(png_ptr->usr_channels*
png_ptr->usr_bit_depth, png_ptr->width)) + 1);
return;
}
}
#endif
png_compress_IDAT(png_ptr, NULL, 0, Z_FINISH);
}
#ifdef PNG_WRITE_INTERLACING_SUPPORTED
void
png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass)
{
static PNG_CONST png_byte png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
static PNG_CONST png_byte png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
png_debug(1, "in png_do_write_interlace");
if (pass < 6)
{
switch (row_info->pixel_depth)
{
case 1:
{
png_bytep sp;
png_bytep dp;
unsigned int shift;
int d;
int value;
png_uint_32 i;
png_uint_32 row_width = row_info->width;
dp = row;
d = 0;
shift = 7;
for (i = png_pass_start[pass]; i < row_width;
i += png_pass_inc[pass])
{
sp = row + (png_size_t)(i >> 3);
value = (int)(*sp >> (7 - (int)(i & 0x07))) & 0x01;
d |= (value << shift);
if (shift == 0)
{
shift = 7;
*dp++ = (png_byte)d;
d = 0;
}
else
shift--;
}
if (shift != 7)
*dp = (png_byte)d;
break;
}
case 2:
{
png_bytep sp;
png_bytep dp;
unsigned int shift;
int d;
int value;
png_uint_32 i;
png_uint_32 row_width = row_info->width;
dp = row;
shift = 6;
d = 0;
for (i = png_pass_start[pass]; i < row_width;
i += png_pass_inc[pass])
{
sp = row + (png_size_t)(i >> 2);
value = (*sp >> ((3 - (int)(i & 0x03)) << 1)) & 0x03;
d |= (value << shift);
if (shift == 0)
{
shift = 6;
*dp++ = (png_byte)d;
d = 0;
}
else
shift -= 2;
}
if (shift != 6)
*dp = (png_byte)d;
break;
}
case 4:
{
png_bytep sp;
png_bytep dp;
unsigned int shift;
int d;
int value;
png_uint_32 i;
png_uint_32 row_width = row_info->width;
dp = row;
shift = 4;
d = 0;
for (i = png_pass_start[pass]; i < row_width;
i += png_pass_inc[pass])
{
sp = row + (png_size_t)(i >> 1);
value = (*sp >> ((1 - (int)(i & 0x01)) << 2)) & 0x0f;
d |= (value << shift);
if (shift == 0)
{
shift = 4;
*dp++ = (png_byte)d;
d = 0;
}
else
shift -= 4;
}
if (shift != 4)
*dp = (png_byte)d;
break;
}
default:
{
png_bytep sp;
png_bytep dp;
png_uint_32 i;
png_uint_32 row_width = row_info->width;
png_size_t pixel_bytes;
dp = row;
pixel_bytes = (row_info->pixel_depth >> 3);
for (i = png_pass_start[pass]; i < row_width;
i += png_pass_inc[pass])
{
sp = row + (png_size_t)i * pixel_bytes;
if (dp != sp)
memcpy(dp, sp, pixel_bytes);
dp += pixel_bytes;
}
break;
}
}
row_info->width = (row_info->width +
png_pass_inc[pass] - 1 -
png_pass_start[pass]) /
png_pass_inc[pass];
row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,
row_info->width);
}
}
#endif
static void
png_write_filtered_row(png_structrp png_ptr, png_bytep filtered_row,
png_size_t row_bytes);
#ifdef PNG_WRITE_FILTER_SUPPORTED
static png_size_t
png_setup_sub_row(png_structrp png_ptr, const png_uint_32 bpp,
const png_size_t row_bytes, const png_size_t lmins)
{
png_bytep rp, dp, lp;
png_size_t i;
png_size_t sum = 0;
int v;
png_ptr->try_row[0] = PNG_FILTER_VALUE_SUB;
for (i = 0, rp = png_ptr->row_buf + 1, dp = png_ptr->try_row + 1; i < bpp;
i++, rp++, dp++)
{
v = *dp = *rp;
sum += (v < 128) ? v : 256 - v;
}
for (lp = png_ptr->row_buf + 1; i < row_bytes;
i++, rp++, lp++, dp++)
{
v = *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff);
sum += (v < 128) ? v : 256 - v;
if (sum > lmins)
break;
}
return (sum);
}
static png_size_t
png_setup_up_row(png_structrp png_ptr, const png_size_t row_bytes,
const png_size_t lmins)
{
png_bytep rp, dp, pp;
png_size_t i;
png_size_t sum = 0;
int v;
png_ptr->try_row[0] = PNG_FILTER_VALUE_UP;
for (i = 0, rp = png_ptr->row_buf + 1, dp = png_ptr->try_row + 1,
pp = png_ptr->prev_row + 1; i < row_bytes;
i++, rp++, pp++, dp++)
{
v = *dp = (png_byte)(((int)*rp - (int)*pp) & 0xff);
sum += (v < 128) ? v : 256 - v;
if (sum > lmins)
break;
}
return (sum);
}
static png_size_t
png_setup_avg_row(png_structrp png_ptr, const png_uint_32 bpp,
const png_size_t row_bytes, const png_size_t lmins)
{
png_bytep rp, dp, pp, lp;
png_uint_32 i;
png_size_t sum = 0;
int v;
png_ptr->try_row[0] = PNG_FILTER_VALUE_AVG;
for (i = 0, rp = png_ptr->row_buf + 1, dp = png_ptr->try_row + 1,
pp = png_ptr->prev_row + 1; i < bpp; i++)
{
v = *dp++ = (png_byte)(((int)*rp++ - ((int)*pp++ / 2)) & 0xff);
sum += (v < 128) ? v : 256 - v;
}
for (lp = png_ptr->row_buf + 1; i < row_bytes; i++)
{
v = *dp++ = (png_byte)(((int)*rp++ - (((int)*pp++ + (int)*lp++) / 2))
& 0xff);
sum += (v < 128) ? v : 256 - v;
if (sum > lmins)
break;
}
return (sum);
}
static png_size_t
png_setup_paeth_row(png_structrp png_ptr, const png_uint_32 bpp,
const png_size_t row_bytes, const png_size_t lmins)
{
png_bytep rp, dp, pp, cp, lp;
png_size_t i;
png_size_t sum = 0;
int v;
png_ptr->try_row[0] = PNG_FILTER_VALUE_PAETH;
for (i = 0, rp = png_ptr->row_buf + 1, dp = png_ptr->try_row + 1,
pp = png_ptr->prev_row + 1; i < bpp; i++)
{
v = *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff);
sum += (v < 128) ? v : 256 - v;
}
for (lp = png_ptr->row_buf + 1, cp = png_ptr->prev_row + 1; i < row_bytes;
i++)
{
int a, b, c, pa, pb, pc, p;
b = *pp++;
c = *cp++;
a = *lp++;
p = b - c;
pc = a - c;
#ifdef PNG_USE_ABS
pa = abs(p);
pb = abs(pc);
pc = abs(p + pc);
#else
pa = p < 0 ? -p : p;
pb = pc < 0 ? -pc : pc;
pc = (p + pc) < 0 ? -(p + pc) : p + pc;
#endif
p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c;
v = *dp++ = (png_byte)(((int)*rp++ - p) & 0xff);
sum += (v < 128) ? v : 256 - v;
if (sum > lmins)
break;
}
return (sum);
}
#endif
void
png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
{
#ifndef PNG_WRITE_FILTER_SUPPORTED
png_write_filtered_row(png_ptr, png_ptr->row_buf, row_info->rowbytes+1);
#else
png_byte filter_to_do = png_ptr->do_filter;
png_bytep row_buf;
png_bytep best_row;
png_uint_32 bpp;
png_size_t mins;
png_size_t row_bytes = row_info->rowbytes;
png_debug(1, "in png_write_find_filter");
bpp = (row_info->pixel_depth + 7) >> 3;
row_buf = png_ptr->row_buf;
mins = PNG_SIZE_MAX - 256;
best_row = png_ptr->row_buf;
if ((filter_to_do & PNG_FILTER_NONE) != 0 && filter_to_do != PNG_FILTER_NONE)
{
png_bytep rp;
png_size_t sum = 0;
png_size_t i;
int v;
if (PNG_SIZE_MAX/128 <= row_bytes)
{
for (i = 0, rp = row_buf + 1; i < row_bytes; i++, rp++)
{
if (sum > PNG_SIZE_MAX/128 - 256)
break;
v = *rp;
sum += (v < 128) ? v : 256 - v;
}
}
else
{
for (i = 0, rp = row_buf + 1; i < row_bytes; i++, rp++)
{
v = *rp;
sum += (v < 128) ? v : 256 - v;
}
}
mins = sum;
}
if (filter_to_do == PNG_FILTER_SUB)
{
(void) png_setup_sub_row(png_ptr, bpp, row_bytes, mins);
best_row = png_ptr->try_row;
}
else if ((filter_to_do & PNG_FILTER_SUB) != 0)
{
png_size_t sum;
png_size_t lmins = mins;
sum = png_setup_sub_row(png_ptr, bpp, row_bytes, lmins);
if (sum < mins)
{
mins = sum;
best_row = png_ptr->try_row;
if (png_ptr->tst_row != NULL)
{
png_ptr->try_row = png_ptr->tst_row;
png_ptr->tst_row = best_row;
}
}
}
if (filter_to_do == PNG_FILTER_UP)
{
(void) png_setup_up_row(png_ptr, row_bytes, mins);
best_row = png_ptr->try_row;
}
else if ((filter_to_do & PNG_FILTER_UP) != 0)
{
png_size_t sum;
png_size_t lmins = mins;
sum = png_setup_up_row(png_ptr, row_bytes, lmins);
if (sum < mins)
{
mins = sum;
best_row = png_ptr->try_row;
if (png_ptr->tst_row != NULL)
{
png_ptr->try_row = png_ptr->tst_row;
png_ptr->tst_row = best_row;
}
}
}
if (filter_to_do == PNG_FILTER_AVG)
{
(void) png_setup_avg_row(png_ptr, bpp, row_bytes, mins);
best_row = png_ptr->try_row;
}
else if ((filter_to_do & PNG_FILTER_AVG) != 0)
{
png_size_t sum;
png_size_t lmins = mins;
sum= png_setup_avg_row(png_ptr, bpp, row_bytes, lmins);
if (sum < mins)
{
mins = sum;
best_row = png_ptr->try_row;
if (png_ptr->tst_row != NULL)
{
png_ptr->try_row = png_ptr->tst_row;
png_ptr->tst_row = best_row;
}
}
}
if ((filter_to_do == PNG_FILTER_PAETH) != 0)
{
(void) png_setup_paeth_row(png_ptr, bpp, row_bytes, mins);
best_row = png_ptr->try_row;
}
else if ((filter_to_do & PNG_FILTER_PAETH) != 0)
{
png_size_t sum;
png_size_t lmins = mins;
sum = png_setup_paeth_row(png_ptr, bpp, row_bytes, lmins);
if (sum < mins)
{
best_row = png_ptr->try_row;
if (png_ptr->tst_row != NULL)
{
png_ptr->try_row = png_ptr->tst_row;
png_ptr->tst_row = best_row;
}
}
}
png_write_filtered_row(png_ptr, best_row, row_info->rowbytes+1);
#endif
}
static void
png_write_filtered_row(png_structrp png_ptr, png_bytep filtered_row,
png_size_t full_row_length)
{
png_debug(1, "in png_write_filtered_row");
png_debug1(2, "filter = %d", filtered_row[0]);
png_compress_IDAT(png_ptr, filtered_row, full_row_length, Z_NO_FLUSH);
#ifdef PNG_WRITE_FILTER_SUPPORTED
if (png_ptr->prev_row != NULL)
{
png_bytep tptr;
tptr = png_ptr->prev_row;
png_ptr->prev_row = png_ptr->row_buf;
png_ptr->row_buf = tptr;
}
#endif
png_write_finish_row(png_ptr);
#ifdef PNG_WRITE_FLUSH_SUPPORTED
png_ptr->flush_rows++;
if (png_ptr->flush_dist > 0 &&
png_ptr->flush_rows >= png_ptr->flush_dist)
{
png_write_flush(png_ptr);
}
#endif
}
#endif