VHS Effect Shader for Unity

A custom Unity shader that recreates the nostalgic visual artifacts of VHS recordings, including scanlines, color bleeding, noise, distortion, and chromatic aberration effects.

VHS.mp4

Features

• Authentic VHS Artifacts: Scanlines, color bleeding, static noise, and horizontal distortion
• Customizable Parameters: Fine-tune intensity, frequency, and speed of all effects
• Real-time Animation: Time-based effects for dynamic VHS-style degradation
• Easy Integration: Simple post-processing script for immediate use
• Performance Optimized: Efficient shader implementation suitable for real-time applications

Quick Start

1. Grab the setup for Quad and Canvas/Image from TvSetupScene.unity

2. Customize the Effect

   • Select the VHSMaterial in the Project window
   • Adjust parameters in the Inspector to achieve your desired look

Shader Parameters

Parameter	Range	Description
_ScanlineIntensity	0-4	Controls the strength of horizontal scanlines
_NoiseIntensity	0-2	Controls the amount of static/noise overlay
_ColorBleed	0-10	Controls chromatic aberration and color channel offset
_Distortion	0-10	Controls horizontal wobble/distortion intensity
_WobbleFrequency	0-110	Controls the frequency of the wobble effect
_WobbleSpeed	0-20	Controls the speed of animated distortion
_ScanlineCount	Float	Number of scanlines across the screen

Project Structure

Assets/VHS/
├── Shaders/
│   └── VHSEffect.shader          # Main VHS effect shader
├── Scripts/
│   └── VHSPostProcess.cs         # Post-processing component
├── Materials/
│   └── VHSMaterial.mat           # Pre-configured material
├── Textures/
│   └── VHSRenderTexture.renderTexture
└── Scenes/
    └── TvSetupScene.unity        # Demo scene

Usage Examples

Basic Post-Processing Setup

using UnityEngine;
using VHS.Scripts;

public class VHSController : MonoBehaviour
{
    public Material vhsMaterial;
    
    void Start()
    {
        var postProcess = Camera.main.gameObject.AddComponent<VhsPostProcess>();
        postProcess._vhsMaterial = vhsMaterial;
    }
}

Runtime Parameter Control

public class VHSEffectController : MonoBehaviour
{
    public Material vhsMaterial;
    
    private void Update()
    {
        // Animate noise intensity over time
        float noise = Mathf.Sin(Time.time) * 0.5f + 0.5f;
        vhsMaterial.SetFloat("_NoiseIntensity", noise);
        
        // Control distortion with input
        if (Input.GetKey(KeyCode.Space))
        {
            vhsMaterial.SetFloat("_Distortion", 2.0f);
        }
    }
}

Technical Details

Built for Unity's built-in render pipeline

Implementation Notes

The shader implements several key VHS characteristics:

1. Scanlines: Sine wave-based horizontal lines with adjustable intensity
2. Color Grading: Subtle desaturation and blue tint typical of VHS
3. Chromatic Aberration: RGB channel separation for color bleeding effect
4. Noise: Time-based random static overlay
5. Distortion: Animated horizontal wobble using sine waves

Contributing

Feel free to submit issues, fork the repository, and create pull requests for any improvements.

License

This project is licensed under the MIT License - see the LICENSE file for details.