Can I edit whatever VLC looks at to determine aspect ratio for play?

[Kevin]

I've been playing around with some .webm files that are 480 x 360--anamorphic?. When I play them in VLC, I have to manually change the aspect ratio to get them to display properly as 16:9.

I know that can resize them to 720 x 360, which works fine if I save as H.264/aac in .mp4 (my preferred default), but I get progressively bad a/v sync).

Is there some parameter editable in AVM that will leave the original resolution but provide the proper signal to VLC that it needs to be stretched horizontally to 16:9 for display? Might be moot at present since I don't appear to be able to save it in it's original VP8 codec in a .webm container, but thought I'd ask for future reference.

[mean]

Container => configure=>force display width
No re-encoding needed

[Kevin]

Container => configure=>force display width
No re-encoding needed

Thank you. I assume that I'd have to choose the .MKV muxer as that's the only one that has the option you mention. My original file had the .WEBM extension. Does that make any difference?

Unfortunately, following your suggestion (with COPY) for both Video and Audio output still results in a file that, although displayed in the correct aspect ratio, has the identical progressively out-of-sync problem that I get when I convert the Webm (VP8/OggVorbis) file to H.264.

The out-of-sync problem does not manifest when playing the original file in VLC, but DOES manifest when playing it in AVM. Is there some known problem with this newer video format and AVM?

[Jan Gruuthuse]

And when playing the newly avidedemux saved video in VLC, do you have the out-of-sync problem?
If not: the audio track 0 (1st) is it AC3?
If multiple audio tracks, not channels!, select stereo track as track 0 (1st).

It could help developer(s) when you provide (upload):
- 10 seconds duration of original webm video
- 10 seconds of that video processed and saved with avidemux with the out-of-sync problem.

ps:- Use a free dropbox account, mega or similar webservice (free public access, without registration to download your uploaded video) thank you.

[Kevin]

Yes, I should have made more clear that the .WEBM files that play synced in VLC go out of sync even when played raw inside AVM. They also go out of sync when saved by AVM in H.264/AAC and played in VLC. I'll try to upload something when I have time. Am I the only one who's reported this behavior--i.e., a synced .WEBM file that goes out of sync when loaded into AVM--even before saving?

[Jan Gruuthuse]

not really:
Original video: source video: VP8 webm
Target video: target video from VP8 webm

[Kevin]

I'm sorry, was the 2nd of those 2 files supposed to demonstrate out-of-sync? It appeared in sync to me.

[Kevin]

I should add that your samples were only 2 mins in length but my files were 30-45 mins in length and the sync degradation was pronounced toward the end.

[Jan Gruuthuse]

No, to indicate I've not come across the audio sync problem, as you mentioned.
So what is your work flow. Step by Step.

[Kevin]

downloaded .WEBM file (no clue how created, but VP8/Ogg Vorbis)

1 - Play in VLC - synced all the way through
2 - Load into AVM - it gets progressively more out of sync as I move through the video within AVM, sampling portions by using the slider
3 - Select COPY for Audio and Video and MKV for output muxer (selecting force 16:9 display in Configure) - per Means

save the file as .MKV

4 - Play .MKV in VLC - it gets progressively more out of sync as I sample portions w/i VLC

The identical result occurs if I instead save as H.264/AAC in .MP4 container.

[Jan Gruuthuse]

video clip NTSC (30/60 fps) or PAL (25/50 fps) style video?
audio running befor or after image?
what size of video file your talking about?

[Kevin]

video clip NTSC (30/60 fps) or PAL (25/50 fps) style video?
audio running befor or after image?
what size of video file your talking about?

NTSC presumably; VLC reports Codec: Google/On2's VP8 Video (VP80); Frame rate:30.000300; Decoded format: Planar 4:2:0 YUV; Audio: Vorbis Audio (vorb); encoder:Google

audio is running after the image (i.e. audio is delayed)

"my files were 30-45 mins in length" (80-145 mb)

[Jan Gruuthuse]

if the source video has similar size could you upload
- source video
- converted video with audio sync issue
Time permitting developer(s) could eventually look at this and see what is going on.

ps:- Use a free dropbox account, mega or similar webservice (free public access, without registration to download your uploaded video) thank you.