png_set_tRNS

Name

png_set_tRNS -- set transparency values for images

Synopsis

#include <png.h>

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"