I found myself disappointed with a lot of VHS style post effects in games, they tend to just throw some horizontal chromatic aberration and noise and call it a day. I studied the artifacts of real VHS encoding and created this much more realistic image effect.
This effect is for Unity's Post Processing package in the built-in render pipeline.
Click here for the Universal Render Pipeline version
The elements of this effect are:
In VHS tapes and many other file formats, color information is stored in lower quality than luminance information. This effect blurs the image, extracts the blurry chrominance, and combines it with the high resolution luminance. It uses the real math used for color compression.
Colors are smeared to the right due to analog signal delay
This is a simple noise overlay, but it also applies to the chrominance separately from the luminance, to simulate how the chrominance data would have its own noise.
I don't know what causes it, but a common artifact in VHS tapes is bright white pixels with trails fading off to the right. I generate these on the GPU and merge them early on in the effect.
A distinct feature of VHS video is dark and light fringes to the left and right of sharp vertical edges. This is implemented using a slightly blurred buffer from the color bleeding step offset to the right.
With all of these working together you get a much more authentic VHS filter!