Bc1 Da File Extra Quality -

The system will output the embedded quality flag. If it returns Quality: Standard , you cannot upgrade it without re-creating the file from the original source. If it returns Quality: Extra , you are safe.

ffmpeg -i input.mkv -c:v libx264 -preset slow -crf 18 -c:a copy bc1_da_extra_quality.mp4 bc1 da file extra quality