Open Source Summit + Embedded Linux Conference Europe 2020

The Video4Linux2(v4l2) is a complex subsystem in Linux that offers great capabilities for configuring a complete video capture pipeline. This presentation focuses on the challenges of taking a photo with a digital sensor, that in most cases is not adapted to the ambient scenery, and how dedicated hardware and software can help the simple photographer to take the best quality photo that they can. A hardware and software pipeline starts from the basic raw pixel data that comes from the sensor, and it goes through several processing stages, from interpolation of raw BAYER matrix and color space conversion to RGB space, color correction, brightness and contrast adjustment, white balance algorithms to adjust to ambient light, and in the end converting to a user friendly image format type. The presentation allows a non-experienced photographer, or a photographer used to classic cameras, to understand the difficulties of digital photography, and how Linux, and especially v4l2, can control, adjust, and automatically perform tasks that will help anyone take photos easy, with minimum amount of effort. The end goal is to understand the functionality of an Embedded Linux Camera.