Preserve audio in 360

[Ellingson]

Is your feature request related to a problem? Please describe. When processing GoPro MAX 360 files, the ffmpeg option "-c:a aac" is added. This causes both audio streams (one is AAC, the other is PCM) to be re-encoded. I would like the original audio streams left alone. Just copy them.

Describe the solution you'd like Offer option in setting to leave PCM audio stream or to re-encode to AAC.

[Ellingson]

Okay, I looked at this and have a possible suggestion.

When using FFMPEG, make the target container MOV and not MP4. This will allow the audio streams to be copied (no PCM to AAC conversion). I'm trying to keep the surround 4-channel audio. A nice side effect is that the join happens much faster.

NOTES:

• Change target from MP4 to MOV
• Use just one "-map 0" command as this will copy all streams and keep the "-ignore_unknown" to skip the two unknown codecs (which are the GoPro TCD and GoPro SOS streams)
• Don't change audio encoding as MOV supports existing formats

ffmpeg -y -f concat -i your_path_to/filelist.txt -c copy -map 0 -ignore_unknown your_output_path/final.mov
udtacopy your_path_to/the_first_GoPro_file.360 your_output_path/final.mov

and of course, then rename the .mov to .360

I found it keeps everything and joins very fast.

THANK YOU!

[rubegartor]

It sounds pretty good, unfortunately it is impossible for me to guarantee correct operation since I do not have .360 files right now, could you share some so I can carry out the tests?

Thanks!

[Ellingson]

Sure! I sent a link to your GMail account. Let me know how I can help further.

[rubegartor]

I've been playing with the MOV format and .360 files (thanks a lot for the video files), honestly I have not seen a better performance, it even takes a little longer to process, although it will depend on the hardware that each one uses, it also produces a larger output file size (MOV - 6,82GB vs MP4 - 6,21GB). A point in favor, as you mention, is that by processing everything in the mov format, the PCM audio can be preserved. Since this has its pros and cons, I propose adding a new option that allows you to select the video format to use.

[Ellingson]

That PCM audio is the spatial audio and is nice to have when viewing the video using a VR headset.

[rubegartor]

I understand, I think the best thing is to add an option to be able to preserve the audio in PCM, I will develop this option when I can in my free time, I will notify any update on this topic in this issue

[rubegartor]

Added in new version 1.3.2 available now