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streamffmpegdebianmjpeg

ffmpeg - Continuously stream webcam to single .jpg file (overwrite)

I have installed ffmpeg and mjpeg-streamer. The latter reads a .jpg file from /tmp/stream and outputs it via http onto a website, so I can stream whatever is in that folder through a web browser.

I wrote a bash script that continuously captures a frame from the webcam and puts it in /tmp/stream:

while true
do
    ffmpeg -f video4linux2 -i /dev/v4l/by-id/usb-Microsoft_Microsoft_LifeCam_VX-5000-video-index0 -vframes 1 /tmp/stream/pic.jpg
done

This works great, but is very slow (~1 fps). In the hopes of speeding it up, I want to use a single ffmpeg command which continuously updates the .jpg at, let's say 10 fps. What I tried was the following:

ffmpeg -f video4linux2 -r 10 -i /dev/v4l/by-id/usb-Microsoft_Microsoft_LifeCam_VX-5000-video-index0 /tmp/stream/pic.jpg

However this - understandably - results in the error message:

[image2 @ 0x1f6c0c0] Could not get frame filename number 2 from pattern '/tmp/stream/pic.jpg'
av_interleaved_write_frame(): Input/output error

...because the output pattern is bad for a continuous stream of images.

Is it possible to stream to just one jpg with ffmpeg?

Thanks...

Solution

  • It is possible to achieve what I wanted by using:

    ./mjpg_streamer -i "input_uvc.so -r 1280×1024 -d /dev/video0 -y" -o "output_http.so -p 8080 -w ./www"

    ...from within the mjpg_streamer's directory. It will do all the nasty work for you by displaying the stream in the browser when using the address: http://{IP-OF-THE-SERVER}:8080/ It's also light-weight enough to run on a Raspberry Pi.

    Here is a good tutorial for setting it up.

    Thanks for the help!