png_set_rgb_to_gray_fixed 1712 third_party/libpng/png.h extern PNG_EXPORT(void,png_set_rgb_to_gray_fixed) PNGARG((png_structp png_ptr,
png_set_rgb_to_gray_fixed  694 third_party/libpng/pngrtran.c    png_set_rgb_to_gray_fixed(png_ptr, error_action, red_fixed, green_fixed);