Unity3d Post Processing package contains different algorithms that add effects and filters to your camera. Some many other tutorials and videos exist on the internet about installing this package to your Unity3D project but many of them are already deprecated and unable to use.
In this writing, I’m going to show how to install this package to Unity3D 2019.4
The first step in installing this package is opening:
Window -> Package Manager
After waiting for a little, you can see a package named Post Processing in the left menu. Click the Post Processing package then click install.
After installing the package close the Package Manager and return to Unity3D.
You can see Post Processing in the packages window after installing.
Open the Runtime directory, which is under PostProcessing/PostProcessing/ directory in project panel.
Drag and Drop PostProcessLayer.cs and PostProcessVolume.cs files to the Camera.
After drag and drop your camera must have this settings inside its inpector.
Top of the inspector you can see Layer settings click it and click Add Layer
Add a new layer, I use ‘camera’ as a layer name but you can rename it.
You can add effects by clicking add effect button.