Output file corrupted when recording the screen for a given duration.

[cy_rus]

Hello,
I am trying to start VLC using command line arguments in order to record the screen activity. The recording duration will be variable : between 2 h and 3 h. One image per second is enough. It should start as soon as a user opens a windows session and should stop as soon as soon as he logs out.

The following code produces a valid mp4 file :

Code: Select all

"C:\Program Files (x86)\VideoLAN\VLC\vlc.exe" screen:// --no-one-instance --screen-follow-mouse --screen-fps=1 --no-audio --sout "#transcode{vcodec=h264,vb=400,fps=1,scale=1,width=auto,height=auto,acodec=none}:duplicate{dst=std{access=file,mux=mp4,dst='Test.mp4'}}"

However, when I try to start VLC hidden for a recording session of 30 s (just testing) the mp4 file output is corrupted. Here is the code :

"C:\Program Files (x86)\VideoLAN\VLC\vlc.exe" screen:// -I dummy --dummy-quiet --no-one-instance --screen-follow-mouse --screen-fps=1 --no-audio --start-time=0 --run-time=30 --stop-time=30 --sout "#transcode{vcodec=h264,vb=400,fps=1,scale=1,width=auto,height=auto,acodec=none}:duplicate{dst=std{access=file,mux=mp4,dst='Test.mp4'}}" vlc://quit

I am stuck there. I feel that VLC does not close itself right when I use vlc://quit and --start-time=0 --run-time=30 --stop-time=30. Could it be that some kind of recording buffer is lost when VLC quits ?

Do you have any suggestions ? Am I doing something wrong ? Thanks in advance.

[InTheWings]

time variables have only effect on playback of timed media.
screen capture has undefined timing.

[cy_rus]

Hello InTheWings,

Thanks for your answer. I understand. So, according to you, it explains the fact that VLC quits without saving what it has recorded, right ? (VLC still quits after 30 s so I thought it was really working).

If I don't use vlc://quit, --start-time, --run-time and --stop-time, I still need to find a way to start VLC so that it records the screen activity until the user logs out of windows.

For instance, the following code could be executed each time the user logs on Windows:

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"C:\Program Files (x86)\VideoLAN\VLC\vlc.exe" screen:// -I dummy --dummy-quiet --no-one-instance --screen-follow-mouse --screen-fps=1 --no-audio -- --sout "#transcode{vcodec=h264,vb=400,fps=1,scale=1,width=auto,height=auto,acodec=none}:duplicate{dst=std{access=file,mux=mp4,dst='Test.mp4'}}"

However, I have no way to close VLC properly so that the output file is saved correctly. Neither can I ask the user to close it by himself because it has to stay in the background and to be automatic (still, the user knows that everything he does is recorded for security purposes ; it is clear from the beginning).

What can I do ? Is there a file format that would still be functionnal/repairable if it is not closed properly ? Other toughts ?