marcegeek / v4l2_webcam

Webcam Streaming with V4L2 and SDL

This code basically handles a webcam, activates the stream mode and renders it on a SDL Window.

Most part of the code was based on some other implementations like: https://github.com/kryali/SmileTime/blob/master/SDL-capture-example.cpp http://www.cs.fsu.edu/~baker/devices/projects/pendawchi/src/capture.c https://jwhsmith.net/2014/12/capturing-a-webcam-stream-using-v4l2/

In these cases, the developer converted YUYV (grabbed from webcam) to RGB, to be able to draw it in an SDL_Surface. So, I didn't wanted to learn such algorithm, and by using SDL2 I created a texture with YUY2 as pixel format, and so we can draw YUV frames directly without any convertion.

For MJPEG, SDL2 loads the "picture" from memory, create a texture and renders. Easier in this case.

Notes:

• This code just implements YUVY and MJPEG, but better cameras should have another formats
• It's a very basic support, just an example of how to do it

References: http://sdl.beuc.net/sdl.wiki/SDL_Overlay https://en.wikipedia.org/wiki/YUV

Build

To test this code, need the following dependencies:

• meson (build system)
• SDL2-devel
• SDL2_image-devel

If you want to try this app using flatpak, you can follow the steps below:

• Install flatpak
• Execute make (it will install this application locally)
• Execute "flatpak run org.test.V4lWebcam" to run the app