这是第一个问题，因为我一直在寻找以前遇到的所有其他问题的答案，感谢所有在这里做出贡献的人。
我按照本指南使用 gphoto2 和 ffmpeg 将我的 Fuji X-T2 实时馈送用作网络摄像头：
https://medium.com/nerdery/dslr-webcam-setup-for-linux-9b6d1b79ae22
当我第一次启动机器并打开相机时，它运行良好：
$ pkill -f gphoto2
（卸载相机作为卷）
$ gphoto2 --stdout --capture-movie | ffmpeg -i - -vcodec rawvideo -pix_fmt yuv420p -f v4l2 /dev/video0
ffmpeg version 4.4-6ubuntu5 Copyright (c) 2000-2021 the FFmpeg developers
built with gcc 11 (Ubuntu 11.2.0-7ubuntu1)
configuration: --prefix=/usr --extra-version=6ubuntu5 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libdav1d --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librabbitmq --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzimg --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-pocketsphinx --enable-librsvg --enable-libmfx --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-nvenc --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared
libavutil 56. 70.100 / 56. 70.100
libavcodec 58.134.100 / 58.134.100
libavformat 58. 76.100 / 58. 76.100
libavdevice 58. 13.100 / 58. 13.100
libavfilter 7.110.100 / 7.110.100
libswscale 5. 9.100 / 5. 9.100
libswresample 3. 9.100 / 3. 9.100
libpostproc 55. 9.100 / 55. 9.100
Capturing preview frames as movie to 'stdout'. Press Ctrl-C to abort.
[mjpeg @ 0x55b4c5b39340] Format mjpeg detected only with low score of 25, misdetection possible!
Input #0, mjpeg, from 'pipe:':
Duration: N/A, bitrate: N/A
Stream #0:0: Video: mjpeg (Baseline), yuvj422p(pc, bt470bg/unknown/unknown), 1024x768, 25 tbr, 1200k tbn, 25 tbc
Stream mapping:
Stream #0:0 -> #0:0 (mjpeg (native) -> rawvideo (native))
[swscaler @ 0x55b4c5b8c800] deprecated pixel format used, make sure you did set range correctly
Output #0, video4linux2,v4l2, to '/dev/video0':
Metadata:
encoder : Lavf58.76.100
Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p(tv, bt470bg/unknown/unknown, progressive), 1024x768, q=2-31, 235929 kb/s, 25 fps, 25 tbn
Metadata:
encoder : Lavc58.134.100 rawvideo
frame= 444 fps= 32 q=-0.0 Lsize=N/A time=00:00:17.76 bitrate=N/A speed=1.29x
但是，如果我关闭相机并在当天晚些时候尝试再次运行，我最终会收到以下错误消息：
gphoto2 --stdout --capture-movie | ffmpeg -i - -vcodec rawvideo -pix_fmt yuv420p -f v4l2 /dev/video0
ffmpeg version 4.4-6ubuntu5 Copyright (c) 2000-2021 the FFmpeg developers
built with gcc 11 (Ubuntu 11.2.0-7ubuntu1)
configuration: --prefix=/usr --extra-version=6ubuntu5 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libdav1d --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librabbitmq --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzimg --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-pocketsphinx --enable-librsvg --enable-libmfx --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-nvenc --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared
libavutil 56. 70.100 / 56. 70.100
libavcodec 58.134.100 / 58.134.100
libavformat 58. 76.100 / 58. 76.100
libavdevice 58. 13.100 / 58. 13.100
libavfilter 7.110.100 / 7.110.100
libswscale 5. 9.100 / 5. 9.100
libswresample 3. 9.100 / 3. 9.100
libpostproc 55. 9.100 / 55. 9.100
Capturing preview frames as movie to 'stdout'. Press Ctrl-C to abort.
[mjpeg @ 0x5635c5ca0340] Format mjpeg detected only with low score of 25, misdetection possible!
Input #0, mjpeg, from 'pipe:':
Duration: N/A, bitrate: N/A
Stream #0:0: Video: mjpeg (Baseline), yuvj422p(pc, bt470bg/unknown/unknown), 1024x768, 25 tbr, 1200k tbn, 25 tbc
Stream mapping:
Stream #0:0 -> #0:0 (mjpeg (native) -> rawvideo (native))
[swscaler @ 0x5635c5cfc600] deprecated pixel format used, make sure you did set range correctly
[video4linux2,v4l2 @ 0x5635c5ca4080] ioctl(VIDIOC_G_FMT): Invalid argument
Could not write header for output file #0 (incorrect codec parameters ?): Invalid argument
Error initializing output stream 0:0 --
Conversion failed!
我目前唯一的解决方案是重新启动桌面 - 请问有什么关于如何修复/排除故障的想法吗？