News:

--

Main Menu

Append video problem

Started by w3bk3rn3l, October 30, 2019, 09:10:59 PM

Previous topic - Next topic

w3bk3rn3l

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

#1
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.

w3bk3rn3l

I think I understood. But the 2 files have the same codes, which is H.264.

eumagga0x2a

#3
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?

w3bk3rn3l

No warning at all. I am using Linux version and can't find any admlog.

eumagga0x2a

Oops, please launch Avidemux from terminal and redirect stdout and stderr to file:

avidemux3_qt5 > ~/admlog.txt 2>&1

w3bk3rn3l

I am attaching the compressed file.

eumagga0x2a

#7
[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.

w3bk3rn3l

No, it's Display All Alerts. But I didn't get any.

eumagga0x2a

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

Too late here now. I will do that tomorrow and post here.
Thanks for your support.