我已经使用 Logitech C270 网络摄像头好几年了，我的系统上安装了 Ubuntu 20.10，没有任何问题。但从昨天开始，网络摄像头停止在 Zoom 和所有其他视频捕获程序中输出视频。摄像头上的灯会亮起，表示它正在捕获视频。dmesg 和 lsusb 表示检测到了摄像头，但没有显示任何错误。除了安装内核更新外，我不知道我做了什么可能导致这种情况。
我尝试恢复到较旧的内核版本 linux-image-5.8.0-55-generic（我安装的最新版本是 linux-image-5.8.0-59-generic），没有任何变化。
我能找到的唯一反馈是运行 guvcview。输出如下：
GUVCVIEW: version 2.0.6
GUVCVIEW: couldn't open /home/etrochim/.config/guvcview2/video0 for read: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
ALSA lib pcm_dsnoop.c:642:(snd_pcm_dsnoop_open) unable to open slave
ALSA lib pcm_dmix.c:1090:(snd_pcm_dmix_open) unable to open slave
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.rear
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.center_lfe
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.side
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
jack server is not running or cannot be started
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
jack server is not running or cannot be started
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
ALSA lib pcm_oss.c:377:(_snd_pcm_oss_open) Unknown field port
ALSA lib pcm_oss.c:377:(_snd_pcm_oss_open) Unknown field port
ALSA lib pcm_usb_stream.c:486:(_snd_pcm_usb_stream_open) Invalid type for card
ALSA lib pcm_usb_stream.c:486:(_snd_pcm_usb_stream_open) Invalid type for card
ALSA lib pcm_dmix.c:1090:(snd_pcm_dmix_open) unable to open slave
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
jack server is not running or cannot be started
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
V4L2_CORE: Could not grab image (select timeout): Resource temporarily unavailable
V4L2_CORE: Could not grab image (select timeout): Resource temporarily unavailable
V4L2_CORE: Could not grab image (select timeout): Resource temporarily unavailable
V4L2_CORE: Could not grab image (select timeout): Resource temporarily unavailable
V4L2_CORE: Could not grab image (select timeout): Resource temporarily unavailable
V4L2_CORE: Could not grab image (select timeout): Resource temporarily unavailable
V4L2_CORE: Could not grab image (select timeout): Resource temporarily unavailable
GUVCVIEW: (status) saving video to /home/etrochim/my_video-1.mkv
ENCODER: add stream 0 to stream list
ENCODER: add stream 1 to stream list
ENCODER: (matroska) add seekhead entry 0 (max 10)
ENCODER: (matroska) add seekhead entry 1 (max 10)
V4L2_CORE: Could not grab image (select timeout): Resource temporarily unavailable
V4L2_CORE: Could not grab image (select timeout): Resource temporarily unavailable
V4L2_CORE: Could not grab image (select timeout): Resource temporarily unavailable
V4L2_CORE: Could not grab image (select timeout): Resource temporarily unavailable
V4L2_CORE: Could not grab image (select timeout): Resource temporarily unavailable
V4L2_CORE: Could not grab image (select timeout): Resource temporarily unavailable
V4L2_CORE: Could not grab image (select timeout): Resource temporarily unavailable
对于可能出现什么问题您有什么想法吗？
答案1
当然，我发布问题后就解决了这个问题。网络摄像头通过显示器上的 USB 端口连接到我的桌面。我最初尝试断开显示器和桌面之间的 USB 电缆并重新连接，但没有成功。但断开显示器和网络摄像头之间的连接后却成功了。我不知道为什么，但至少我又可以正常工作了。