lsusb告诉Bus 003 Device 003: ID 046d:0825 Logitech, Inc. Webcam C270。
ls -la /dev/video*告诉
crw-rw----+ 1 root video 81, 0 juin 2 12:47 /dev/video0
crw-rw----+ 1 root video 81, 1 juin 2 12:47 /dev/video1
有或没有sudo，guvcview -d /dev/video0告诉
GUVCVIEW: version 2.0.6
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Aucun fichier ou dossier de ce type
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Aucun fichier ou dossier de ce type
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Aucun fichier ou dossier de ce type
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Aucun fichier ou dossier de ce type
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Aucun fichier ou dossier de ce type
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Aucun fichier ou dossier de ce type
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Aucun fichier ou dossier de ce type
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Aucun fichier ou dossier de ce type
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Aucun fichier ou dossier de ce type
ALSA lib pcm.c:2642:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.rear
ALSA lib pcm.c:2642:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.center_lfe
ALSA lib pcm.c:2642:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.side
ALSA lib pcm_route.c:869:(find_matching_chmap) Found no matching channel map
ALSA lib pcm_route.c:869:(find_matching_chmap) Found no matching channel map
ALSA lib pcm_route.c:869:(find_matching_chmap) Found no matching channel map
ALSA lib pcm_route.c:869:(find_matching_chmap) Found no matching channel map
Cannot connect to server socket err = Aucun fichier ou dossier de ce type
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 = Aucun fichier ou dossier de ce type
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
Cannot connect to server socket err = Aucun fichier ou dossier de ce type
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): Ressource temporairement non disponible
V4L2_CORE: Could not grab image (select timeout): Ressource temporairement non disponible
V4L2_CORE: Could not grab image (select timeout): Ressource temporairement non disponible
V4L2_CORE: Could not grab image (select timeout): Ressource temporairement non disponible
...最后一行永远重复。
如果我切换到video1，GUI 会告诉我“未找到视频设备”，并且我有一个列表框，其中包含两次相同的输入设备 (046d:0825)。第二个没有任何反应，选择第一个会返回上面的日志。
这是外置网络摄像头。声音正常，但没有图像。
lsb_release -a告诉
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 20.04.2 LTS
Release: 20.04
Codename: focal