png_do_dither    3498 third_party/libpng/png.h PNG_EXTERN void png_do_dither PNGARG((png_row_infop row_info,
png_do_dither    1494 third_party/libpng/pngrtran.c       png_do_dither((png_row_infop)&(png_ptr->row_info), png_ptr->row_buf + 1,