在Docker中使用cvlc访问主机网络摄像头

Question

我正在尝试为流媒体服务器设置Docker容器，但当我试图从容器中访问主机的网络摄像头时遇到了麻烦。

我使用以下命令运行容器：docker run -t -i --privileged --rm my/image /bin/bash。VLC拒绝以root用户身份运行，因此我在Dockerfile中创建了一个新用户。

下面是我用来测试摄像头是否正常工作的命令：cvlc v4l2:///dev/video2:chroma=h264 --sout '#std{access=file,mux=ps,dst=test.h264}'。主机上的一切都按预期运行。

当我尝试在容器中运行该命令时，我看到了以下内容：

[0x7fc300003108] mux_ps mux: Open
[0x7fc300003108] main mux debug: using sout mux module "mux_ps"
[0x7fc300000b78] main stream output debug: muxer support adding stream at any time
[0x7fc300000b78] main stream output debug: muxer prefers to wait for all ES before starting to mux
[0x7fc300000f48] stream_out_standard stream out debug: using `file/ps://test.mp4'
[0x7fc300000f48] main stream out debug: using sout stream module "stream_out_standard"
[0x7fc308000ab8] main input debug: using timeshift granularity of 50 MiB, in path '/tmp'
[0x7fc308000ab8] main input debug: `v4l2:///dev/video2:chroma=h264' gives access `v4l2' demux `' path `/dev/video2:chroma=h264'
[0x7fc308000ab8] main input debug: creating demux: access='v4l2' demux='' location='/dev/video2:chroma=h264' file='/dev/video2:chroma=h264'
[0x7fc300004088] main demux debug: looking for access_demux module matching "v4l2": 20 candidates
[0x7fc300004088] v4l2 demux debug: opening device '/dev/video2'
[0x7fc300004088] v4l2 demux error: cannot open device '/dev/video2': Permission denied
[0x7fc300004088] v4l2 demux debug: opening device '/dev/video2'
[0x7fc300004088] v4l2 demux error: cannot open device '/dev/video2': Permission denied
[0x7fc300004088] main demux debug: no access_demux modules matched
[0x7fc308000ab8] main input debug: creating access 'v4l2' location='/dev/video2:chroma=h264', path='/dev/video2:chroma=h264'
[0x7fc300005988] main access debug: looking for access module matching "v4l2": 25 candidates
[0x7fc300005988] v4l2 access debug: opening device '/dev/video2'
[0x7fc300005988] v4l2 access error: cannot open device '/dev/video2': Permission denied
[0x7fc300005988] main access debug: no access modules matched
[0x7fc308000ab8] main input error: open of `v4l2:///dev/video2:chroma=h264' failed
[0x7fc308000ab8] main input error: Your input can't be opened
[0x7fc308000ab8] main input error: VLC is unable to open the MRL 'v4l2:///dev/video2:chroma=h264'. Check the log for details.
[0x927218] main playlist debug: dead input

当我尝试运行类似的工具如ffmpeg时，我看到了相同的权限被拒绝的消息。有没有提示我可能出错的地方？

Answer 1

问题是我的用户不是video组的成员。此外，我还必须将视频设备的权限更改为root.video。

更多信息请点击此处：http://www.tldp.org/HOWTO/html_single/Webcam-HOWTO/#PERMISSIONS