png_choose_filter  373 libavcodec/pngenc.c                         crow = png_choose_filter(s, crow_buf, progressive_buf, top, pass_row_size, bits_per_pixel>>3);
png_choose_filter  389 libavcodec/pngenc.c             crow = png_choose_filter(s, crow_buf, ptr, top, row_size, bits_per_pixel>>3);