png_set_tRNS
Name
png_set_tRNS -- set transparency values for images
Synopsis
void
png_set_tRNS
(png_structp
png_ptr, png_infop
info_ptr, png_bytep
trans, int
num_trans, png_color_16p
trans_values);
Description
png_set_tRNS() shall set the transparency data for paletted images and
image types that don't need a full alpha channel.
For a paletted image, png_set_tRNS() shall set the array of transparency values
for the palette colors to "trans". The number of transparency entries is given
by "num_trans".
For non-paletted images, png_set_tRNS() shall set the single color value or
graylevel to "trans_values"