The VideoLAN Forums

Posted: **13 Jun 2021 11:58**

Hi,

I'm trying to record and display live video from a webcam connected to my computer, using the command prompt.
I tried using the following syntax (generated by the wizard):

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"C:\Program Files (x86)\VideoLAN\VLC\vlc.exe" dshow:// :dshow-vdev="HD Pro Webcam C920" :dshow-aspect-ratio=16\:9 :dshow-size=1920x1080 :dshow-fps=30 :sout=#transcode{vcodec=h264,acodec=mpga,ab=128,channels=2,samplerate=44100,scodec=none}:duplicate{dst=file{dst=D:\\\\TEST_VID.mp4},dst=display} :no-sout-all :sout-keep

While the recording is just fine, the display freezes showing only the first frame. What am I doing wrong?

Any help will be apprecheated!

P.S.: I tried on two different computers and got the same result.

Posted: **20 Jun 2021 14:43**

If I try only to record by using the following line it works just fine:

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dos('"C:\Program Files (x86)\VideoLAN\VLC\vlc.exe" dshow:// :dshow-vdev="HD Pro Webcam C920" :dshow-aspect-ratio=16\:9 :dshow-size=1920x1080 :dshow-fps=30 :sout=#transcode{vcodec=h264,acodec=mpga,ab=128,channels=2,samplerate=44100,scodec=none}:standard{access=file,dst="D:\TEST_VID.mp4"} :no-sout-all :sout-keep')

I also tried to flip the order between the transcoding and the duplicating (maybe duplicating transcoded video is causing the problem?!) using the following syntax:

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dos('"C:\Program Files (x86)\VideoLAN\VLC\vlc.exe" dshow:// :dshow-vdev="HD Pro Webcam C920" :dshow-aspect-ratio=16\:9 :dshow-size=1920x1080 :dshow-fps=30 :sout=#duplicate{dst=display,transcode{vcodec=h264,acodec=mpga,ab=128,channels=2,samplerate=44100,scodec=none}:standard{access=file,dst="D:\TEST_VID.mp4"}} :no-sout-all :sout-keep')

which displays the video perfectly but i get the following error:

duplicate stream out error: * ignore unknown option `transcode'

followed by the message:

duplicate stream out error: * ignore unknown option `standard'

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Recording Webcam Video Doesn't Display

Recording Webcam Video Doesn't Display

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