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[libpng14] Imported from libpng-1.4.17beta01.tar

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Glenn Randers-Pehrson
2015-08-19 12:19:45 -05:00
parent 41de766f12
commit cbd9e435ad
14 changed files with 21 additions and 452 deletions
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131
pngwrite.c
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@@ -593,11 +593,6 @@ png_create_write_struct_2(png_const_charp user_png_ver, png_voidp error_ptr,
png_set_write_fn(png_ptr, NULL, NULL, NULL);
#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
png_set_filter_heuristics(png_ptr, PNG_FILTER_HEURISTIC_DEFAULT,
1, NULL, NULL);
#endif
return (png_ptr);
}
@@ -1012,14 +1007,6 @@ png_write_destroy(png_structp png_ptr)
png_free(png_ptr, png_ptr->time_buffer);
#endif
#ifdef 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, png_sizeof(jmp_buf));
@@ -1167,123 +1154,19 @@ png_set_filter(png_structp png_ptr, int method, int filters)
* better compression.
*/
#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* GRR 970116 */
#ifdef PNG_FLOATING_POINT_SUPPORTED
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");
if (png_ptr == NULL)
return;
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)(png_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)(png_sizeof(png_uint_16) * num_weights));
png_ptr->inv_filter_weights = (png_uint_16p)png_malloc(png_ptr,
(png_uint_32)(png_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)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));
png_ptr->inv_filter_costs = (png_uint_16p)png_malloc(png_ptr,
(png_uint_32)(png_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);
}
}
PNG_UNUSED(png_ptr)
PNG_UNUSED(heuristic_method)
PNG_UNUSED(num_weights)
PNG_UNUSED(filter_weights)
PNG_UNUSED(filter_costs)
}
#endif
#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
void PNGAPI