We have collected the most relevant information on V4l2 Audio. Open the URLs, which are collected below, and you will find all the info you are interested in.
Documentation:Modules/v4l2 - VideoLAN Wiki
https://wiki.videolan.org/Documentation:Modules/v4l2/
These options do not apply to audio streams in compressed data. v4l2-adev < string > : Audio input device default value: "". v4l2-audio-method < integer > : Allowed audio input methods (bitmask: 1 for OSS, 2 for ALSA) default value: 3. v4l2-stereo : Capture audio in stereo default value: enabled. v4l2-samplerate < integer > : Audio input sample ...
linux - Can v4l2 be used to read audio and video from the ...
https://stackoverflow.com/questions/917060/can-v4l2-be-used-to-read-audio-and-video-from-the-same-device
IF you want your driver to play with gstreamer etc. a separate audio device generally is what is expected. Most of the cheap v4l2 capture card's audio is only an analog pass through with a volume control requiring a jumper to capture the audio via the sound card's line input. Share Improve this answer answered Dec 24 '09 at 19:53 wkulecz 1 1
GitHub - licaibiao/v4l2_video_audio_encode_live
https://github.com/licaibiao/v4l2_video_audio_encode_live
rtsp/live555_rtsp_live_v4l2. 《使用live555 直播来自v4l2的摄像头数据》. 使用x246软编码将v4l2采集到的摄像头数据编码成h264数据流，然后借助live555库将h264流推送到流媒体服务器.
7.22. ioctl VIDIOC_G_AUDIO, VIDIOC_S_AUDIO — The …
https://www.kernel.org/doc/html/latest/userspace-api/media/v4l/vidioc-g-audio.html
Audio inputs have one writable property, the audio mode. To select the current audio input and change the audio mode, applications initialize the index and mode fields, and the reserved array of a struct v4l2_audio structure and call the VIDIOC_S_AUDIO ioctl. Drivers may switch to a different audio mode if the request cannot be satisfied.
1.5. Audio Inputs and Outputs — The Linux Kernel …
https://www.kernel.org/doc/html/v4.9/media/uapi/v4l/audio.html
Assumed two composite video inputs and two audio inputs exist, there may be up to four valid combinations. The relation of video and audio connectors is defined in the audioset field of the respective struct v4l2_input or struct v4l2_output, where each bit represents the index number, starting at zero, of one audio input or output.
Jamie McClelland | video4linux and audio
https://current.workingdirectory.net/posts/2010/video4linux-and-audio/
Audio proved to be the most difficult piece - way harder than video. Many of my problems seemed to have been largely specific to my computer, but not all of them. Part of the problem with audio is that, on linux, it’s a real mess. There are a half dozen methods in use for accessing your audio card.
Video and audio lag when using v4l2 with audio file ...
https://github.com/mpv-player/mpv/issues/9595
Reproduction steps and actual behavior. According to this page v4l Input I want to stream video from video capture card dev/video0, if only using v4l2 it can play smoothly. mpv av://v4l2:/dev/video0 --profile=low-latency. But after adding audio file both video and audio are laggy with lots of drop frame.
Where I can find example in using v4l2 codec driver ...
https://stackoverflow.com/questions/20436592/where-i-can-find-example-in-using-v4l2-codec-driver
v4l2 is very liberal when it comes to formats: e.g. capture devices can deliver frames in virtually any format. So if you are writing a user-land tool (application, library,...; as opposed to a kernel-driver), though shalt not fiddle with codecs (if you can avoid it).
v4l2src - GStreamer
https://gstreamer.freedesktop.org/documentation/video4linux2/v4l2src.html
v4l2src can be used to capture video from v4l2 devices, like webcams and tv cards. Example launch lines gst-launch-1.0 v4l2src ! xvimagesink This pipeline shows the video captured from /dev/video0 tv card and for webcams. gst-launch-1.0 v4l2src ! jpegdec ! xvimagesink This pipeline shows the video captured from a webcam that delivers jpeg images.
V4L capturing - LinuxTVWiki
https://linuxtv.org/wiki/index.php/V4L_capturing
Much like audio, you can spend as long as you like cleaning your video. But whereas audio cleaning tends to be about doing one thing really well (separating out frequencies of signal and noise), video cleaning tends to be about getting decent results in different circumstances.
Now you know V4l2 Audio
Now that you know V4l2 Audio, we suggest that you familiarize yourself with information on similar questions.
