Appending AVI

stephen22 · 10th November 2020, 15:50

I'm often editing soundtrack (audio from another file) without altering the video (direct stream copy) - quick and lossless.

Sometimes the audio ends up not exactly the same length as the video. This doesn't seem to matter - until I start concatenating files. Ill-fitting audio in a segment will push the audio of the next segment out of sync.

Is there a simple way of trimming/expanding audio of an AVI file to fit, which doesn't ivolve extracting the audio and editing it in an audio editor?

videoh · 10th November 2020, 16:36

Don't know about in Vdub, but in Avisynth you have the ++ operator to join clips, doing what you asked for. Nevertheless, it does require decoding/reencoding. I don't know of any tools that can do that in the compressed domain, but let's see what others know about.

stephen22 · 10th November 2020, 17:54

Yes, thanks, in fact I'm looking for a ++ operation in VD - I guess there isn't one.

Suddernly occurred to me - easy to check in File Information which gives the length of both.

shekh · 11th November 2020, 01:48

Do you know there is option Video->Select range->Cut off audio...
You should enable it to minimize a/v length differences. Other than that, there is nothing to help. Appending large amount of segments will definitely increase sync errors.

stephen22 · 11th November 2020, 16:10

Thanks, no, didn't know that. All 3 boxes seem to be ticked by default, but alas doesn't help with concatenation.

10th November 2020, 15:50	#1 \| Link
stephen22 Registered User Join Date: Jan 2007 Posts: 88	Appending AVI I'm often editing soundtrack (audio from another file) without altering the video (direct stream copy) - quick and lossless. Sometimes the audio ends up not exactly the same length as the video. This doesn't seem to matter - until I start concatenating files. Ill-fitting audio in a segment will push the audio of the next segment out of sync. Is there a simple way of trimming/expanding audio of an AVI file to fit, which doesn't ivolve extracting the audio and editing it in an audio editor?

11th November 2020, 01:48	#4 \| Link
shekh Registered User Join Date: Mar 2015 Posts: 775	Do you know there is option Video->Select range->Cut off audio... You should enable it to minimize a/v length differences. Other than that, there is nothing to help. Appending large amount of segments will definitely increase sync errors. __________________ VirtualDub2

10th November 2020, 16:36	#2 \| Link
videoh Useful n00b Join Date: Jul 2014 Posts: 1,667	Don't know about in Vdub, but in Avisynth you have the ++ operator to join clips, doing what you asked for. Nevertheless, it does require decoding/reencoding. I don't know of any tools that can do that in the compressed domain, but let's see what others know about.

10th November 2020, 17:54	#3 \| Link
stephen22 Registered User Join Date: Jan 2007 Posts: 88	Yes, thanks, in fact I'm looking for a ++ operation in VD - I guess there isn't one. Suddernly occurred to me - easy to check in File Information which gives the length of both.

11th November 2020, 16:10	#5 \| Link
stephen22 Registered User Join Date: Jan 2007 Posts: 88	Thanks, no, didn't know that. All 3 boxes seem to be ticked by default, but alas doesn't help with concatenation.