Avidemux Forum

Avidemux => Windows => Topic started by: me444 on June 04, 2020, 12:16:20 PM

Title: Since april 30 versions, problem to cut some MP4 in copy mode (corrupted output)
Post by: me444 on June 04, 2020, 12:16:20 PM
I'm not an expert in codecs and formats, so i try to explain my problem from a usage perspective as best as i can:

Until (including) nightly avidemux_r200415_win64Qt5_96.zip  april 15th, #96 all worked fine.
Since #97 from april 30th (avidemux_r200430_win64Qt5_97.zip) i encounted:

Attempt to cut some MP4 files in copy mode:
- Step forward to a keyframe > 0 ad set as start marker
- Step forward again and set an end marker
- Use "copy" for both video and audio portion and save the file
Result:
- The ADM builtin player does not play it (it does not find any contents resp. keyframe after position 0)
- Using MPC-HC Home cinema as player:
  Audio playback will start immediately. Video playback has a delay of a couple of seconds until it begins the playback.

Maybe the file(s) does not meet the ADM's format expectation, but, as told, before april 30th it did work perfectly.

Remark: i would like to avoid a re-encoding of the file which was not necessary before at all.

I'm able to provide a smal testcase (appraox. 16MB) together with small cut results from april 15th and the latest nightly from june 01  .... if i only knew where to store them.
 

Title: Re: Since april 30 versions, problem to cut some MP4 in copy mode (corrupted output)
Post by: eumagga0x2a on June 04, 2020, 12:39:19 PM
Quote from: me444 on June 04, 2020, 12:16:20 PM
Attempt to cut some MP4 files in copy mode:
- Step forward to a keyframe > 0 ad set as start marker
- Step forward again and set an end marker

What do you mean by "step" here? Usually it means a single frame. Or do you mean "seek to the next keyframe"?
Quote- Use "copy" for both video and audio portion and save the file
Result:
- The ADM builtin player does not play it (it does not find any contents resp. keyframe after position 0)
- Using MPC-HC Home cinema as player:
  Audio playback will start immediately. Video playback has a delay of a couple of seconds until it begins the playback.

Maybe the file(s) does not meet the ADM's format expectation, but, as told, before april 30th it did work perfectly.

Difficult to tell.

QuoteI'm able to provide a smal testcase (appraox. 16MB) together with small cut results from april 15th and the latest nightly from june 01  .... if i only knew where to store them.

Please use WeTransfer (you don't need to provide an email address, even if it looks as it it were necessary!), Mega, Dropbox or Google Drive. I would need only the source video and steps to reproduce, but getting the output from the cut won't harm.
Title: Re: Since april 30 versions, problem to cut some MP4 in copy mode (corrupted output)
Post by: me444 on June 04, 2020, 01:04:44 PM
Hi eumagga0x2a,

ok, via WeTransfer:  https://we.tl/t-RKofVXKAw7

> What do you mean by "step" here?
5th button from the left "Go to next keyframe (UP)"
Title: Re: Since april 30 versions, problem to cut some MP4 in copy mode (corrupted output)
Post by: eumagga0x2a on June 04, 2020, 02:51:02 PM
Thank you, I can reproduce the issue, looking into it.

The workaround for now: save the entire video in copy mode as MPEG-TS. The resulting .ts file can be cut as usual, also when saving as .mp4.
Title: Re: Since april 30 versions, problem to cut some MP4 in copy mode (corrupted output)
Post by: eumagga0x2a on June 04, 2020, 06:09:53 PM
Regression from April 17 fixed by [muxerGate/videoCopySeiInjector] Fix typo of doom which broke copy mode for H.264 streams with SEI unregistered data present when we actually injected SEI message (https://github.com/mean00/avidemux2/commit/2169adc5b32443c6cbbbbe6e136ca4c93caa9769).

Thank you very much for your report.
Title: Re: Since april 30 versions, problem to cut some MP4 in copy mode (corrupted output)
Post by: me444 on June 05, 2020, 08:09:27 AM
Great news - thanks a lot for your efforts ! :) :)
I'll check with the next nightly
Title: Re: Since april 30 versions, problem to cut some MP4 in copy mode (corrupted output)
Post by: me444 on June 06, 2020, 09:09:42 AM
Tried latest nightly (avidemux_r200606_win64Qt5_105.zip) and find it to work fine again.
Perfect! :) Many thanks eumagga0x2a !  :)
Title: Re: Since april 30 versions, problem to cut some MP4 in copy mode (corrupted output)
Post by: eumagga0x2a on June 06, 2020, 10:16:57 AM
You are welcome, my apologies for inconvenience. Please don't hesitate to report problems (especially regressions) right away in the future.