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Channel Merge

Channel Merge
Color

Combines up to four single-channel images into one RGBA image, with per-channel fill defaults for any unconnected input.

Channel Merge takes up to four single-channel inputs (R, G, B, A) and assembles them into a single RGBA image. Each input is optional: when a channel is unconnected, it’s filled with a per-channel constant (Zero, One, or a custom value of your choice from 0 to 255).

Defaults are 0 for R/G/B and 255 for A, so wiring just one channel produces a usable image instead of garbage. At least one input must be connected, and all connected inputs must share the same dimensions; the output matches that size.

This is the natural inverse of Channel Split, and it also accepts the single-channel output of nodes like Mask From Image, Mask Paint, Mask Refine, Magic Wand, or Color Range.

Parameters

Section titled “Parameters”

Pins

RMask
InputOptional
GMask
InputOptional
BMask
InputOptional
AMask
InputOptional
ImageImage
Output

Red Channel

Red FillChoice
Default: Zero Range: Zero / One / Custom
When red input is not connected

Fill mode for the red channel when not connected

Red ValueInteger
Default: 0 Range: 0–255
When fill mode == Custom

Constant value used to fill the red channel

Green Channel

Green FillChoice
Default: Zero Range: Zero / One / Custom
When green input is not connected

Fill mode for the green channel when not connected

Green ValueInteger
Default: 0 Range: 0–255
When fill mode == Custom

Constant value used to fill the green channel

Blue Channel

Blue FillChoice
Default: Zero Range: Zero / One / Custom
When blue input is not connected

Fill mode for the blue channel when not connected

Blue ValueInteger
Default: 0 Range: 0–255
When fill mode == Custom

Constant value used to fill the blue channel

Alpha Channel

Alpha FillChoice
Default: One Range: Zero / One / Custom
When alpha input is not connected

Fill mode for the alpha channel when not connected (default: One)

Alpha ValueInteger
Default: 0 Range: 0–255
When fill mode == Custom

Constant value used to fill the alpha channel

Usage Tips

Section titled “Usage Tips”
  • Pair with Channel Split to operate on individual channels and recombine. For example, blur only the alpha or curve only the red channel.
  • Wire a single channel into R and leave G/B/A on defaults to view that channel as a red-on-black RGBA image.
  • Assemble a normal map from externally processed channels by wiring them into R, G, B with A defaulted to 255. To generate a normal map from a height map, use the dedicated Normal Map node instead.
  • Use Custom fill with a specific value (e.g. 128) to set a channel to a fixed neutral instead of pure black or white.
Section titled “Related Nodes”