Channel Merge

Overview

Combines separate grayscale component images into a color image. Use it to restore components split by Channel Split after processing them, or to assemble colors from mask images.

In each input, white means a stronger component and black means a weaker one.

Examples

• Strengthen only the lightness from Channel Split with Levels, then restore the color with Channel Merge.
• Use grayscale noise as the equivalent of an OKLCH-C input to vary chroma.
• Connect a mask to alpha to cut out the assembled color.

Usage tips

• The standard pattern is a round trip through channel_split: split → process components → merge again.
• A, B, and C are required. Every component image, including a connected Alpha input, must have the same dimensions or evaluation returns a NodeError. Only Alpha may be left unconnected, in which case it defaults to fully opaque.
• Port labels follow the selected space: L/C/H for OKLCH, H/S/V for HSV, and R/G/B for RGB.
• Inventing color from grayscale sources is also powerful. For example, use noise for lightness and a gradient for hue to build a procedural color image.

Related nodes

• channel_split — the matching node for decomposition
• mask — a focused alternative for cutting out by an alpha component
• gradient_map — a simpler route from one component to color