Stack Overflow
Stack Overflow

Questions tagged [video4linux]

Video4Linux or V4L is a video capture application programming interface (API) for Linux, supporting many USB webcams, TV tuners, and other devices. Video4Linux is closely integrated with the Linux kernel.

Video4Linux or V4L is a video capture application programming interface (API) for Linux, supporting many USB webcams, TV tuners, and other devices. Video4Linux is closely integrated with the Linux kernel.

References

  1. Video4Linux - Wikipedia
41 questions
1
vote
0 answers

Need help configuring FFMPEG to work with a webcams h264 stream

I have been trying to get a H264 stream from a H264 usb webcam working but I am not making much progress so I'm hoping someone knows FFMPEG better than me! There are dozens of questions/answers on SO but none solve my problem. In short, I get a very…
The Welsh Dragon
  • 519
  • 1
  • 4
  • 19
1
vote
0 answers

Missing gstreamer plugin

I've never used gstreamer before but I'm trying to use it and video4linuxloopback to turn my IPad into a jury-rigged webcam. I have an app that outputs the video from the camera to an IP on the local network but no matter what I did I kept getting…
Admiralthrawnbar
  • 11
  • 2
1
vote
0 answers

ffmpeg overwrite v4l2-ctl configuration -> how to do real raw device to network copy?

I need to do a real device to a tcp socket copy like : cat /dev/video0 | /bin/nc 127.0.0.1 8000 -w 1 This very basic command line work for my case. I want to do the same, but with the ffmpeg process. The aim is to standardize the streaming process,…
Serveurperso
  • 11
  • 3
1
vote
1 answer

How to cross compile for arm video for linux and udev

I am trying to make our application work on an Arm device, specs: Architecture: aarch64 Byte Order: Little Endian Model name: ARMv8 Processor rev 3 (v8l) and for this I have installed the necessary cross compiler sudo…
Ferenc Deak
  • 34,348
  • 17
  • 99
  • 167
1
vote
2 answers

webcam + external camera failure, cannot access /dev/video*: No such file or directory

I hope someone out there can help me! I'm working on a Toshiba SATELLITE-L50-A-1DN, and I am having problems connecting a camera to the USB ports, as well as the integrated webcam not being recognised. I am using Ubuntu 16.04 with kernel…
Richard Owen
  • 11
  • 1
  • 2
1
vote
1 answer

Raspberry Pi ffmpeg video4linux2, v4l2 mmap no such device

On my Raspberry pi I've installed ffmpeg. At the begin I type uv4l --driver raspicam --auto-video_nr --width 640 --height 480 --encoding jpeg to run driver. Then I check if devoce0 is registered: ls -la /dev/video* and it returns video0 so it is…
Robert
  • 2,571
  • 10
  • 63
  • 95
1
vote
0 answers

MBP Retina Isight and FFmpeg

I try to reach the video stream from my brand new MacBook Pro Retina (Mavericks) to use it as an input in ffmpeg (and stream it again via RTMP). I've tried different solutions in other stack overflow's topics but none seems to work : wacaw -L…
Manuhoz
  • 89
  • 2
  • 12
1
vote
0 answers

How to retrieve frames from video4linux in c++?

I'm trying to save pixel data from webcam feed. How do I save frames from video4linux with c++?
user2826094
  • 133
  • 4
0
votes
0 answers

Video4linux: Video encoder driver never delivers encoded frames

I have an SoM based on the Qualcomm Snapdragon 410, which has a hardware video encoder which is exposed as a Video4Linux device. I have some C code which uses the device according to the M2M encoder interface…
mort
  • 704
  • 2
  • 9
  • 21
0
votes
0 answers

Are the pixel values in this vendor specific RAW bayer format (V4L2_PIX_FMT_IPU3_SBGGR10) discontiguous in memory?

I'm working with a 10 bit RAW bayer pixel format used by the MIPI-CSI and ISP hardware ("IPU3") on an Intel platform. The memory layout of the RAW format is described here:…
mthiffau
  • 123
  • 1
  • 10
0
votes
0 answers

Bad Image Quality, Raspberry Pi 3 V4L USB Camera MJPG OpenCV

I have a 4K USB Camera connected to a Raspberry Pi 3 and the same model of camera on a RPi 4. After capturing the image via OpenCV: cap = cv2.VideoCapture(0) fourcc = cv2.VideoWriter_fourcc(*'MJPG') cap.set(cv2.CAP_PROP_FOURCC,…
Vertago
  • 315
  • 2
  • 16
0
votes
0 answers

ffmpeg: single frame from video is highly overexposed image

I am using ffmpeg on a Raspberry Pi 400, attached to a camera array to capture one image from each camera. Most images generated are highly overexposed and washed out. I am trying to understand which command line options I should set to prevent…
mcgregor94086
  • 1,467
  • 3
  • 11
  • 22
0
votes
1 answer

RaspberryPi HLS streaming with nginx and ffmpeg; v4l2 error: ioctl(VIDIOC_STREAMON): Protocol error

I'm trying to realize a baby monitoring with a Raspberry Pi (Model 4B, 4GB RAM) and an ordinary Webcam (with integrated Mic). I followed this Tutorial: https://github.com/DeTeam/webcam-stream/blob/master/Tutorial.md Shortly described: I installed…
Mirco Weber
  • 11
  • 2
0
votes
0 answers

How can I record my usb webcam to an mp4 format?

I have been trying for hours to record my USB webcam to a .mp4 file format. The only format that works is .avi right now. I am on a RPi using video4linux2. This code does not work: ffmpeg -f video4linux2 -framerate 30 -s 1280x720 -i /dev/video0…
Todd Murphy
  • 9
  • 4
0
votes
0 answers

Is there a way using C++ to get the number of video devices and their names inside linux?

Currently I use ls -ltrh /dev/video* to list all the video devices in the terminal, or cat /sys/class/video4linux/video0/name to display the name of that video device in terminal. I wonder is there a way to call some api in the C++ to get these…
Tim
  • 47
  • 7
1
2
3