Author Topic: Append video problem  (Read 188 times)

w3bk3rn3l

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Append video problem
« on: October 30, 2019, 09:10:59 PM »
Hi,

I am using version 2.7.4 on ArcosLinux (Arch based) and I made cuts in two mp4 videos. After saving each of them, I opened the first and append the second. I saved with a different name and when I open and play I only see the image and audio of the first one. The audio of the second portion is ok but the image stays grey (like attached picture).

What am I doing wrong?


eumagga0x2a

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Re: Append video problem
« Reply #1 on: October 30, 2019, 09:18:11 PM »
For appended H.264 or HEVC AVCC type (i.e. not AnnexB) streams to be decodable after having been saven in copy mode, the codec configuration (i.e. the extradata) of both streams must match.

For H.264, Avidemux now tries to detect extradata mismatch (but only very cursorily). For HEVC, such a check hasn't been implemented yet.
« Last Edit: October 30, 2019, 09:20:20 PM by eumagga0x2a »

w3bk3rn3l

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Re: Append video problem
« Reply #2 on: October 30, 2019, 09:32:58 PM »
I think I understood. But the 2 files have the same codes, which is H.264.

eumagga0x2a

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Re: Append video problem
« Reply #3 on: October 30, 2019, 09:41:14 PM »
Not only the codec type must match but all the settings which tell a H.264 decoder how to interpret the bits which are fed to it. You can see the start of extradata in the video properties dialog (Alt+Enter). Load each video separately and compare the hex values (complete extradata are printed to the log).

Have you got no warning about codec configuration mismatch when saving appended video? If there wasn't any, could you please load each file separately, close Avidemux, then compress and attach admlog.txt from %localappdata%\avidemux to your reply?
« Last Edit: October 30, 2019, 09:45:44 PM by eumagga0x2a »

w3bk3rn3l

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Re: Append video problem
« Reply #4 on: October 30, 2019, 10:13:05 PM »
No warning at all. I am using Linux version and can't find any admlog.

eumagga0x2a

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Re: Append video problem
« Reply #5 on: October 30, 2019, 10:28:47 PM »
Oops, please launch Avidemux from terminal and redirect stdout and stderr to file:

Code: [Select]
avidemux3_qt5 > ~/admlog.txt 2>&1

w3bk3rn3l

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Re: Append video problem
« Reply #6 on: October 30, 2019, 10:40:25 PM »
I am attaching the compressed file.

eumagga0x2a

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Re: Append video problem
« Reply #7 on: October 30, 2019, 10:48:31 PM »
Code: [Select]
[Editor]The video codec has some extradata (43 bytes)

 0000 : .d......gd.....P   01 64 00 1f ff e1 00 1c 67 64 00 1f ac d1 00 50
 0010 : ...j............   05 bb 01 6a 02 02 02 80 00 00 03 00 80 00 00 1e
 0020 : .......h..,        07 8c 18 89 01 00 04 68 eb 8f 2c




[Editor]The video codec has some extradata (42 bytes)

 0000 : .M@.....gM@...(.   01 4d 40 1f ff e1 00 1b 67 4d 40 1f e8 80 28 02
 0010 : ......@...@.:...   dd 80 b5 01 01 01 40 00 00 fa 40 00 3a 98 03 c6
 0020 : .D....h..          0c 44 80 01 00 04 68 eb ef 20

As you can easily see, extradata don't match.

Regarding missing warning, is the silent mode* turned on?

*) "Message level: no alerts" in the Preferences.
« Last Edit: October 30, 2019, 10:50:19 PM by eumagga0x2a »

w3bk3rn3l

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Re: Append video problem
« Reply #8 on: October 30, 2019, 10:56:08 PM »
No, it's Display All Alerts. But I didn't get any.

eumagga0x2a

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Re: Append video problem
« Reply #9 on: October 30, 2019, 11:07:13 PM »
Then please perform the append + save in copy mode operation and provide the log. Alternatively, please save a very short sample (2 GOPs should suffice) from each file and upload them e.g. to WeTransfer to allow me to investigate the options.

w3bk3rn3l

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Re: Append video problem
« Reply #10 on: October 30, 2019, 11:19:41 PM »
Too late here now. I will do that tomorrow and post here.
Thanks for your support.