Avidemux Forum

Avidemux => Main version 2.6 => Topic started by: Jonathanfitch.1 on June 21, 2023, 08:43:41 PM

Title: Corrected audio sync is not saved
Post by: Jonathanfitch.1 on June 21, 2023, 08:43:41 PM
When I preview a video with audio sync issues, having chosen the correct audio advance, the preview plays perfectly. But after I then save the video, the audio advance that I previewed is not saved. any ideas?

Thanks for our help!
Title: Re: Corrected audio sync is not saved
Post by: eumagga0x2a on June 21, 2023, 10:16:12 PM
Do you refer to the latest available nightly build or at least the last release (2.8.1)? Anything older is unsupported. Please also mention the muxer (output format) you are using.

If the video has multiple audio tracks, the audio delay combo box in the codec widget as all other settings there affect only the first audio track. To adjust other tracks, you need to use "Select Track" action in the menu "Audio".
Title: Re: Corrected audio sync is not saved
Post by: Jonathanfitch.1 on June 23, 2023, 12:38:37 PM
Hi--Thanks for trying to answer my question. Here's some additinal info. First, I am using version 2.8.1. Second, about the audio tracks, the file properties indicate that there are 2 audio tracks (see attached screenshot #1}. Avidemux sayys thatere's only one track however, and doesn't offer the option to select tracks (see screenshot #2). Any ideas?
Title: Re: Corrected audio sync is not saved
Post by: eumagga0x2a on June 23, 2023, 04:41:59 PM
The first screenshot doesn't show the number of audio tracks, it just states that the first one has two channels.

Audio tracks are not selected in the codecs widget, the latter operates on the first track only. To access more tracks (if the video has multiple audio tracks), use the dedicated location in the GUI I already described in my previous reply.

To enable audio shift, you must check the "Shift" checkbox (I assume you did so). Finally, as delaying audio in MP4 container is done by edit lists, a player without edit list support will play the video as if nothing was changed. For more exact assessment please provide more information and preferably a sample.
Title: Re: Corrected audio sync is not saved
Post by: Jonathanfitch.1 on June 26, 2023, 12:05:53 AM
I was able to work around the problem by converting the file to monaural. Now that the video has only one audio track/channel, avidemux handles the shift just fine. Wish I hadn't had to do that but it's better than living with the poor audio sync.
Title: Re: Corrected audio sync is not saved
Post by: eumagga0x2a on June 26, 2023, 06:19:57 AM
There is absolutely no connection between the number of channels and audio shift. The number of tracks matters, of course, for reasons I tried to explain above.

As audio shift, also for multiple tracks (when set in the "Select Track" dialog in the menu "Audio" – not in the codec widget!), generally works fine for me, please provide more information, especially shift value and which video player is affected (and also try the latest nightly build for the sake of completeness).