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Imported from libpng-0.82.tar

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This commit is contained in:
Guy Schalnat
1995-11-28 11:22:13 -06:00
committed by Glenn Randers-Pehrson
parent 51f0eb4584
commit 0f71645dfe
16 changed files with 1233 additions and 475 deletions
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107
pngwrite.c
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@@ -57,25 +57,30 @@ png_write_info(png_struct *png_ptr, png_info *info)
if (info->valid & PNG_INFO_bKGD)
png_write_bKGD(png_ptr, &(info->background), info->color_type);
#endif
#if defined(PNG_WRITE_hIST_SUPPORTED)
if (info->valid & PNG_INFO_hIST)
png_write_hIST(png_ptr, info->hist, info->num_palette);
#endif
#if defined(PNG_WRITE_pHYs_SUPPORTED)
if (info->valid & PNG_INFO_pHYs)
png_write_pHYs(png_ptr, info->x_pixels_per_unit,
info->y_pixels_per_unit, info->phys_unit_type);
#endif
#if defined(PNG_WRITE_oFFs_SUPPORTED)
if (info->valid & PNG_INFO_oFFs)
png_write_oFFs(png_ptr, info->x_offset, info->y_offset,
info->offset_unit_type);
#endif
#if defined(PNG_WRITE_tIME_SUPPORTED)
if (info->valid & PNG_INFO_tIME)
png_write_tIME(png_ptr, &(info->mod_time));
/* Check to see if we need to write text chunks */
#endif
#if defined(PNG_WRITE_tEXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
if (info->num_text)
{
@@ -84,6 +89,12 @@ png_write_info(png_struct *png_ptr, png_info *info)
/* loop through the text chunks */
for (i = 0; i < info->num_text; i++)
{
if (strlen(info->text[i].key) > 80)
{
(*(png_ptr->warning_fn))(png_ptr,"tEXt keyword more than 80 chars");
continue;
}
/* if chunk is compressed */
if (info->text[i].compression >= 0)
{
@@ -104,7 +115,8 @@ png_write_info(png_struct *png_ptr, png_info *info)
}
}
}
#endif
#endif /* PNG_WRITE_tEXt_SUPPORTED || PNG_WRITE_zTXt_SUPPORTED */
png_ptr->mode = PNG_HAVE_IHDR;
}
/* writes the end of the png file. If you don't want to write comments or
@@ -114,6 +126,9 @@ png_write_info(png_struct *png_ptr, png_info *info)
void
png_write_end(png_struct *png_ptr, png_info *info)
{
if (info && png_ptr->mode == PNG_AFTER_IEND)
return;
/* see if user wants us to write information chunks */
if (info)
{
@@ -122,6 +137,7 @@ png_write_end(png_struct *png_ptr, png_info *info)
if (info->valid & PNG_INFO_tIME)
png_write_tIME(png_ptr, &(info->mod_time));
#endif
#if defined(PNG_WRITE_tEXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
/* check to see if we need to write comment chunks */
if (info->num_text)
@@ -151,10 +167,12 @@ png_write_end(png_struct *png_ptr, png_info *info)
}
}
}
#endif
#endif /* PNG_WRITE_tEXt_SUPPORTED || PNG_WRITE_zTXt_SUPPORTED */
}
/* write end of png file */
png_write_IEND(png_ptr);
png_ptr->mode = PNG_AFTER_IEND;
}
#if defined(PNG_WRITE_tIME_SUPPORTED)
@@ -177,7 +195,7 @@ png_convert_from_time_t(png_time *ptime, time_t ttime)
tbuf = gmtime(&ttime);
png_convert_from_struct_tm(ptime, tbuf);
}
#endif
#endif /* PNG_WRITE_tIME_SUPPORTED */
/* initialize png structure, and allocate any memory needed */
void
@@ -243,11 +261,13 @@ void
png_write_row(png_struct *png_ptr, png_bytef *row)
{
/* initialize transformations and other stuff if first time */
if (png_ptr->row_number == 0 && png_ptr->pass == 0)
if (png_ptr->mode < PNG_HAVE_IDAT)
{
png_write_start_row(png_ptr);
}
png_ptr->mode = PNG_HAVE_IDAT;
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
/* if interlaced and not interested in row, return */
if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
@@ -305,7 +325,7 @@ png_write_row(png_struct *png_ptr, png_bytef *row)
break;
}
}
#endif
#endif /* PNG_WRITE_INTERLACE_SUPPORTED */
/* set up row info for transformations */
png_ptr->row_info.color_type = png_ptr->color_type;
@@ -334,7 +354,7 @@ png_write_row(png_struct *png_ptr, png_bytef *row)
return;
}
}
#endif
#endif /* PNG_WRITE_INTERLACE_SUPPORTED */
/* handle other transformations */
if (png_ptr->transformations)
@@ -367,6 +387,7 @@ png_write_row(png_struct *png_ptr, png_bytef *row)
/* set up the zlib input buffer */
png_ptr->zstream->next_in = png_ptr->row_buf;
png_ptr->zstream->avail_in = (uInt)png_ptr->row_info.rowbytes + 1;
/* repeat until we have compressed all the data */
do
{
@@ -378,9 +399,9 @@ png_write_row(png_struct *png_ptr, png_bytef *row)
if (ret != Z_OK)
{
if (png_ptr->zstream->msg)
png_error(png_ptr, png_ptr->zstream->msg);
(*(png_ptr->error_fn))(png_ptr, png_ptr->zstream->msg);
else
png_error(png_ptr, "zlib error");
(*(png_ptr->error_fn))(png_ptr, "zlib error");
}
/* see if it is time to write another IDAT */
@@ -396,8 +417,77 @@ png_write_row(png_struct *png_ptr, png_bytef *row)
/* finish row - updates counters and flushes zlib if last row */
png_write_finish_row(png_ptr);
#if defined(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 /* PNG_WRITE_FLUSH_SUPPORTED */
}
#if defined(PNG_WRITE_FLUSH_SUPPORTED)
/* Set the automatic flush interval or 0 to turn flushing off */
void
png_set_flush(png_struct *png_ptr, int nrows)
{
png_ptr->flush_dist = (nrows < 0 ? 0 : nrows);
}
/* flush the current output buffers now */
void
png_write_flush(png_struct *png_ptr)
{
char wrote_IDAT;
if (png_ptr->mode != PNG_HAVE_IDAT)
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)
(*(png_ptr->error_fn))(png_ptr, png_ptr->zstream->msg);
else
(*(png_ptr->error_fn))(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_ptr->output_flush_fn))(png_ptr);
}
#endif /* PNG_WRITE_FLUSH_SUPPORTED */
/* free any memory used in png struct */
void
png_write_destroy(png_struct *png_ptr)
@@ -416,6 +506,7 @@ png_write_destroy(png_struct *png_ptr)
png_memset(png_ptr, 0, sizeof (png_struct));
png_memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf));
}
void
png_set_filtering(png_struct *png_ptr, int filter)
{