MP4 export - quality control

[khinkalo]

I've used the mp4 export function a few times (and love you for having implemented it), but it is very rare that I manage to pin the quality meter to desired results. So it always takes 2-3 attempts before coming close. Does the meter actually corresponds to something like the b:v parameter in ffmpeg or does it vastly depend on the content? I'm ideally aiming for close to 10Mbps.

Thank you as always for your continued work

PS. Not to have to start another topic: if I set subtitles to be burned in before exporting, will the final mp4 also have those present?

[Carsten]

Yes to burn-in subtitles - they will show up in the MP4.

The quality parameter is indeed tricky. I understand most people would want to have a datarate/file size indicator, but I don't know if this is possible at all for the MP4 codecs.

I use Handbrake occasionally, but I don't know if data rate control is among it's features for h.264/mp4.

[carl]

The number is passed to FFmpeg as "crf" or "constant rate factor". See https://trac.ffmpeg.org/wiki/Encode/H.264

Are you aiming for some particular perceptual quality, or a target bitrate?