Should I Change the Default Audio Bitrate (384K) Accordingly to Video Properties

Hi fellas, just got into shotcut and it’s amazing. Simple question here for the audio section when export video. If my video file has 128kbps bitrate in audio, should i still leave it as is in the setting which is 384K? I’m confused as the default is quite high, i’m not sure how it is able to create better audio than the original file with lower audio bitrate.

Thanks!

-absolute noob

TL;DR… Using 192k is sufficient when the audio sources are lossy. Using 128k could be sufficient when the sources are high-quality lossless like WAV.

More detail…

You are correct that using 384k cannot create higher quality audio than the original file. However, the higher bitrates can avoid losing quality with each new generation.

For example, if a source is 128k audio, and you export that, then import the copy and export it again, then import that copy and export it again, it only takes a few generations before the quality noticeably suffers. 128k to 128k to 128k is not a lossless transfer of data. Each generation will compromise a little detail simply because that’s what lossy codecs are designed to do. But if the export is 192k, there is room to hold 128k without having to strip much detail if any. 384k as you suspected is overkill if the sources are only 128k.

@Austin Thanks for your reply. May i know how about sample rate for audio? The default is 48000hz, and if the video is 44.100khz, should i change it accordingly or leave it as default?

Same situation.

If there are lots of video/audio sources and most are 48k, then export at 48k. Shotcut will resample any 44.1k audio to 48k automatically.

But if you’re chopping up a single video that’s 44.1k, then export at 44.1k for the least alteration.

EDIT: As always, “it depends”. Some codecs, like Opus, only support 48k (outside of telecom applications anyway). If you try 44.1k and see export errors, then stick with 48k.