PNG_FLAG_MNG_EMPTY_PLTE  907 3rdparty/libpng/pngwutil.c        !(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) &&
PNG_FLAG_MNG_EMPTY_PLTE 1432 3rdparty/libpng/pngwutil.c           (!(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE))) &&