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Does anybody have a glue why I can't get ffmpeg to record my webcam higher than 8 fps, with ffmpeg? I've tried Cheese and GUVCView, under various settings. GUVCView only records a still picture, and Cheese records the audio in mono.

I've tried to force the framerate to 30fps, but then the resulting recording is at the wrong speed, too fast, like in a slapstick movie from the twenties.

My ffmpeg command:

ffmpeg -f alsa -i default -f v4l2 -s 1280x720 -r 30 -i /dev/video0 -c:a copy -b:v 2000k output.mkv

I thought I might record a video in the Web Camera application in Windows 10 - which works - examine the resulting video in ffmpeg, and try to mimick the codecs somehow. However I'm lost at how I can do that.

This is how ffmpeg describes the Windows recording:

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'prufaLenCam_160223.mp4': Metadata: major_brand : mp42 minor_version : 0 compatible_brands: mp41isom creation_time : 2016-02-23 07:56:11 Duration: 00:00:28.50, start: 0.000000, bitrate: 8116 kb/s Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuvj420p(pc), 1280x720 [SAR 1:1 DAR 16:9], 7949 kb/s, 29.69 fps, 30 tbr, 30k tbn, 60 tbc (default) Metadata: creation_time : 2016-02-23 07:56:11 handler_name : VideoHandler encoder : AVC Coding Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 159 kb/s (default) Metadata: creation_time : 2016-02-23 07:56:11 handler_name : SoundHandler No pixel format specified, yuvj420p for H.264 encoding chosen. Use -pix_fmt yuv420p for compatibility with outdated media players.

theodorn
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  • I've been advised, when asking about particular ffmpeg commands, to include the output of the original command, so here it is: http://pastebin.ubuntu.com/15185929/ – theodorn Feb 24 '16 at 06:34

1 Answers1

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Did some more research, and believe I've solved the issue with this command:

ffmpeg -f alsa -i default -f v4l2 -c:v mjpeg -s 1280x720 -i /dev/video0 -t 30 -b:v 2000k test.mp4

Based on information in this question. Thanks to @John Baber-Lucero, who provided the base command, which I adapted for my own system and preferences.

Though I noticed, the picture is frozen for the first few seconds. Not a big problem, I'll just start my recordings with a silence, and cut the bad part out.

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theodorn
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