Unity shader stories - Edge detection using convolution filters
Adding edge detection to a render texture in Unity by using compute shaders to process Sobel filters.
In this tutorial we introduce the VideoPlayer component for adding a video file to a quad in Unity. We then introduce the concept of image convolutions and describe a few examples before implementing the Sobel filters to find the edges of an image. These are then combined and we show how to do thresholding in both a hard and soft manner before colouring and overlaying the edge detection back onto the original video. We do all of this using compute shaders in Unity.
The source code for this project (minus the Adobe stock footage file) is available at:
https://github.com/Firnox/ShaderStori...
Chapters:
0:00 Introduction
0:25 VideoPlayer component and setup
2:45 Image convolution introduction
4:55 Sobel filters
6:00 Shader introduction and greyscale
8:20 Sobel filter shaders
9:15 Running shaders
10:21 Combining Sobel filters
11:04 Thresholding
12:03 Overlaying the edge detection
