PNG_FORMAT_RGBA    43 contrib/examples/pngtopng.c          image.format = PNG_FORMAT_RGBA;
PNG_FORMAT_RGBA    63 example.c               image.format = PNG_FORMAT_RGBA;
PNG_FORMAT_RGBA  2930 png.h          #define PNG_FORMAT_ARGB (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_AFIRST)
PNG_FORMAT_RGBA  2950 png.h          #define PNG_FORMAT_RGBA_COLORMAP (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_COLORMAP)