Volume Leveling on HEVC .mp4 Files

[jmdale1984]

I'm looking for a way to volume level my media collection (which is 95% HEVC .mp4 files) without having to re-encode everything. Being able to do it by the batch would be nice, as there is about 7 TB of files.

Xmedia Recode seems to be able to do this fine with h264 files, but insists on encoding the video (or crashes entirely) with h265/hevc files.

I typically use Handbrake for all of my video encoding, but if there's an option there, I cannot find it. I also have, and am somewhat familiar with Ripbot264, and while it does have a "normalize" option, I don't know of a way to run it without also encoding a video (nor how to run batches with Ripbot).

Does anyone know of a program that can do this?

I'd also like to find reliable software to sync the audio to the video (by retarding or advancing it). Ripbot264 can do this sometimes, but with some files, it seems to fail to move the audio altogether. Not to mention, it also requires re-encoding the file (to h264, which then has to be encoded to hevc). Any advice?

Running a Windows 7 64 bit system.

Thanks in advance. If this is the wrong section, I apologize.

[KarMa]

Something like MKVtoMP4 might be an easy answer, it can do audio only re-encoding with normalization.

https://www.videohelp.com/software/MkvToMp4

[jmdale1984]

Something like MKVtoMP4 might be an easy answer, it can do audio only re-encoding with normalization.

https://www.videohelp.com/software/MkvToMp4

Thanks for the help.

I installed this, but I don't see any way to normalize the audio without also encoding the video... what am I missing?

[Hoser Rob]

7Tb of files? Doesn't your media player have volume normalization?

[jmdale1984]

I use Kodi, and there's no way to do that as far as I can find. At this point, it seems like my best bet is to just convert the worst files back to h264, run them through Xmedia Recode, then convert back to HEVC in Handbrake. Luckily, I think most of the files with the volume out of whack are lower res files. Also lucky I sprung for the i7 instead of the i3 or i5.

[Bernix]

Hi,
i believe reencode video is worst you can do. Lot of time loosing quality. If I were you i would give a try Hybrid. It can just pass through Video and work just with audio, also belive there is more about audio and has batch mode. If not normalize sorry then. But it is robust free software, and i would look here. Of course recommpressing audio will have some impact, but if you are not audiophile and leave enough bitrate for audio will not notice.


Edit: not familiar with Kodi but didnt this help? https://www.reddit.com/r/kodi/comments/421gf7/how_to_normalize_audio_in_kodi/


Bernix

[abolibibelot]

I use Kodi, and there's no way to do that as far as I can find. At this point, it seems like my best bet is to just convert the worst files back to h264, run them through Xmedia Recode, then convert back to HEVC in Handbrake. Luckily, I think most of the files with the volume out of whack are lower res files. Also lucky I sprung for the i7 instead of the i3 or i5.

That's a very inefficient solution, as you'll waste a lot of time and electricity and lose quality at the same time. If you really need to re-encode the audio, you could :
– extract the audio with mp4box

FOR %F in (*.mp4) DO mp4box -add "%F#audio" -new "%~nF.m4a"

– convert the audio with qaac, using its own --normalize switch (and the --limiter switch to prevent possible saturations)

FOR %F in (*.m4a) DO qaac --normalize --limiter "%F" -o "%~nF - qaac.m4a"

– remux the transcoded audio with the untouched video with mp4box

FOR %F in (*.mp4) DO mp4box -add "%F#video" -add "%~nF - qaac.m4a" -new "%~nF - new audio.mp4"

Those are Windows commands, you have to adapt them if you're using a different system. If you add "/R" after "FOR" those commands will process all subdirectories. But processing 7TB all at once would be kinda insane... and completing the conversion of one source MP4 file requires a little more than twice its size in total storage space (size of the source file + size of the converted audio + size of the remuxed file).
With qaac you can also set the quality parameters, but the default setting produces a high quality encoding, which is well advised to transcode from an already lossy compression with no perceptible quality loss. You didn't say if the source files had stereo or 6+ channels audio ; if I'm not mistaken qaac should by default preserve the layout of the input, but this should be verified.