#71 Recorded videos have a duration of zero

[Franco Bugnano]

I'm using Ubuntu 22.04 and I tried recording a video using a Logitech C922 webcam and a Focusrite 2i2 USB audio interface.
For the audio I have to use Jack, or a Jack compatible server (I tried both Jack and PipeWire), in order to be able to route the audio correctly while recording.
Everything seems to work fine, I see the webcam video in the preview window, and when I click "Record Video" I also see the audio meters working correctly.
When I stop recording the video, the size of my_video-1.mkv is only of 772 bytes, and, of course, in such a small size there is no audio or video.
I tried both the version that's available in the default Ubuntu 22.04 repositories, and the version available in the pj-assis PPA, and both have the same behaviour.
The stdout/stderr is as follows (Note that the ALSA errors are before hitting the "Record Video" button, and, as I said, the audio meters during recording work correctly):

GUVCVIEW: version 2.0.8
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: File o directory non esistente
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: File o directory non esistente
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: File o directory non esistente
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: File o directory non esistente
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: File o directory non esistente
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: File o directory non esistente
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: File o directory non esistente
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: File o directory non esistente
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: File o directory non esistente
ALSA lib pcm.c:2664:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.rear
ALSA lib pcm.c:2664:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.center_lfe
ALSA lib pcm.c:2664:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.side
ALSA lib pcm_route.c:877:(find_matching_chmap) Found no matching channel map
ALSA lib pcm_route.c:877:(find_matching_chmap) Found no matching channel map
ALSA lib pcm_route.c:877:(find_matching_chmap) Found no matching channel map
ALSA lib pcm_route.c:877:(find_matching_chmap) Found no matching channel map
ALSA lib pcm_oss.c:397:(_snd_pcm_oss_open) Cannot open device /dev/dsp
ALSA lib pcm_oss.c:397:(_snd_pcm_oss_open) Cannot open device /dev/dsp
ALSA lib confmisc.c:160:(snd_config_get_card) Invalid field card
ALSA lib pcm_usb_stream.c:482:(_snd_pcm_usb_stream_open) Invalid card 'card'
ALSA lib confmisc.c:160:(snd_config_get_card) Invalid field card
ALSA lib pcm_usb_stream.c:482:(_snd_pcm_usb_stream_open) Invalid card 'card'
ENCODER: setting default frame size for audio codec
GUVCVIEW: (status) saving video to /home/fri/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)
AUDIO: (portaudio) Aborting audio stream
AUDIO: Closing audio stream...
ENCODER: (matroska) closing context
ENCODER: (matroska) closing cluster
ENCODER: (matroska)write seekhead
ENCODER: (matroska) end duration = 0 (0,000000)