Filter Shader
BasicShaderFilter Shader
The Filter shader filters another shader or a bitmap. You can use it to adjust a shader or bitmap’s brightness, contrast, hue, saturation, gamma, gradient curves, etc.
The Filter shader is especially useful for adjusting HDRI textures. For example, high-contrast HDRIs with bright lights usually cause flickering in the animation when rendering GI (Image Base Lighting). You can quickly resolve this problem by adjusting the Gamma value.