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On Sun, Jun 15, 2014 at 1:04 PM, Canek Peláez Valdés <caneko@×××××.com> wrote: |
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> On Sun, Jun 15, 2014 at 12:54 PM, <meino.cramer@×××.de> wrote: |
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>> Hi, |
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>> |
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>> After unsuccessfully trying vlc with a Logitech C920 HD Pro Webcam |
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>> (over 2 seconds delay between audio and video). I played around |
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>> with gstreamer and from bits and pieces from the web I build |
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>> this line: |
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>> |
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>> gst-launch-1.0 v4l2src device=/dev/video1 ! video/x-h264,width=1920,height=1080,framerate=30/1 ! \ |
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>> h264parse ! muxout. alsasrc device="hw:3,0" ! queue ! audioconvert ! lamemp3enc ! \ |
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>> muxout. matroskamux name=muxout streamable=true ! filesink location=c920.mp4 |
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>> |
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>> which records a Full HD video with audio to my harddisc. The delay is |
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>> minimal and the sync between audio and video is good. |
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>> |
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>> But there is one disadvantage: |
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>> I cannot see what I am recording and I cannot watch the webcams stream |
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>> before I fire up the script because otherwise the device would be "already |
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>> in use" (I dont like scripts, which simply kill other applications when |
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>> called). |
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>> |
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>> Any ideas or hints how to manage that? |
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> |
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> Use the tee element. I'm in a hurry, so I cannot test a pipeline right |
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> now, but I will try later. Meanwhile, just try to put a queue element |
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> after each path of the tee. |
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> |
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> gst-inspect-1.0 tee |
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|
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OK, it took me a bit of an effort, but this is my pipeline: |
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gst-launch-1.0 v4l2src norm=NTSC device=/dev/video1 ! queue ! |
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deinterlace mode=1 ! videorate ! |
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video/x-raw,format=YV12,width=720,height=480,framerate=30000/1001 ! |
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tee name=t t. ! queue ! videoconvert ! mpeg2enc ! avimux ! filesink |
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location=file.avi t. ! queue ! videoconvert ! autovideosink |
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My hardware is much more limited (analog RGB), so resolution and |
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famerate are accordingly lower. This captures to an AVI file encoded |
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to MPEG2 the video signal, and at the same time it opens a window to |
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show the stream. |
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It should not be that much of a problem to modify it to your needs; |
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just notice that I didn't capture audio. |
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Regards. |
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-- |
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Canek Peláez Valdés |
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Profesor de asignatura, Facultad de Ciencias |
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Universidad Nacional Autónoma de México |
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