Issue losslessly trimming video without re-encoding

[Jabberwockxeno]

I'm trying to trim out parts of VoD's I downloaded from twitch, but for a number of the files, i'm running into issues where the outputted file has the video "frozen" for the durattion of the time periods I cut out from the video, though the audio still plays fine. Intrestingly, VLC seems to show it working, but VLC is buggy to begin with and displays all video as heavily pixellated messes, so even if it were usable in VLC otherwise, the files are still unwatchable due to that there.

I don't think i'm doing anything wrong. I'm using the up and down arrow keys to make sure all the times I trim stuff are on keyframes, and then I save the video file with the video and audio output set to copy, and the ouput format set to Mp4v2/

One of the twitch files I downloaded came out fine from this, but the video itself was downloaded months ago rather then in the past few days, so I suppose it could be something that twitch did to how it saves their video files since then that makes it incompatable with doing this.

Any help or alternative software suggestions of how to do this would be appreciated. Virtualdub won't work because the original files are Mp4's. I can provide a sample of one of the outputted files if it would be helpful upon request.

[eumagga0x2a]

Which Avidemux revision are you referring to? Have you tested with the latest builds from the current git as well with the 2.6.12 release?

It would be preferable to have a source video file rather than an output to play with.

If this is improssible, please run at least

Code Select Expand

ffprobe -report /path/to/a/source/video/file

(or an equivalent which works on Windows) and attach the generated "ffprobe-<DATE>-<TIME>.log" file. Is ffplay capable of playing the source file properly?

[Jabberwockxeno]

Which Avidemux revision are you referring to? Have you tested with the latest builds from the current git as well with the 2.6.12 release?

It would be preferable to have a source video file rather than an output to play with.

If this is improssible, please run at least

Code Select Expand

ffprobe -report /path/to/a/source/video/file

(or an equivalent which works on Windows) and attach the generated "ffprobe-<DATE>-<TIME>.log" file. Is ffplay capable of playing the source file properly?

2.6.1, I'll try with a more recent build when I have the time.

>It would be preferable to have a source video file rather than an output to play with.

Here: https://drive.google.com/open?id=0Bxi90CWdsCj3d2J0dHk3NjRoMzg

Do you still want the ffprobe thing?

[eumagga0x2a]

Actually neither a sample nor a ffprobe report is of any use before you have confirmed that the issue exists in an Avidemux nightly build from the current git. Should such a build exhibit the problem, further testing with a recent release (due to the given description of the issue, I'd recommend 2.6.12 because there were some changes in 2.6.13 which could be related) would be required to check whether it is a regression.

[Jabberwockxeno]

Alright, i'll test it out on that build when I can.

[andrewk8]

I'd recommend 2.6.12 because there were some changes in 2.6.13 which could be related) would be required to check whether it is a regression.

I mostly use ADM to losslessly trim AVC / AAC MP4.  I tried cutting a couple with 2.6.13 Windows x64 and got garbled video.  I didn't have time to trouble-shoot, much less make a meaningful report, so I went back to 2.6.12 and was fine.  Since you mentioned potential issues with 2.6.13 in this area, I wanted to confirm there's something not working right.

[eumagga0x2a]

I mostly use ADM to losslessly trim AVC / AAC MP4.  I tried cutting a couple with 2.6.13 Windows x64 and got garbled video.  [...] I went back to 2.6.12 and was fine.

Please test with the latest nightly build as well. If it similarly fails to cut video properly, please provide a sample.

[andrewk8]

I mostly use ADM to losslessly trim AVC / AAC MP4.  I tried cutting a couple with 2.6.13 Windows x64 and got garbled video.  [...] I went back to 2.6.12 and was fine.

Please test with the latest nightly build as well. If it similarly fails to cut video properly, please provide a sample.

Unfortunately, I don't know what file that was.  I installed avidemux_2.6.13_r160906_win64 and had a different problem, but was not reproducible on other files.  Of the 4 files I tested, I did not have problems with garbled video with this build.  Do you know of something changed in 2.6.12 --> 2.6.13 that was changed again in 2.6.13 --> 2.6.13 nightlies that would lead you to this question and result?

Anyhow,
Avidemux v2.6.13 (160906_d4f378c512b)
File #1: MPEG-4 / HEVC / AAC source, loslessly cut to:

• MP4 Muxer - "Too short The video has been saved but seems to be incomplete."  Didn't remember problems in 2.6.12 Windows x64, but did not test with this file.
  
• MP4v2 Muxer - "Muxer Cannot open" (another forum thread says HEVC is not supported with MP4v2, but I thought I'd try, anyhow, for completeness)
• Mkv Muxer - working

File #2 MPEG-4 / AVC / AAC source, loslessly cut to:

• MP4 Muxer - working

File #3 MPEG-4 / AVC / AAC source, loslessly cut to:

• MP4 Muxer - working

File #4 MPEG-4 / HEVC / AAC source, loslessly cut to:

• MP4 Muxer - working

Attached is the Application Log for the MPEG-4 / HEVC file that wouldn't cut.