ComfyUI Channel Ops (live-preview)

Comfyui custom node that modifies image channels with various per-channel operations across RGB, HSV, and Oklab color-space with live in-node preview

Note: Destination parameter has no effect on any operations other than Overwrite

Operations

Operation	Effect
Invert	Inverts selected channel(s).
Overwrite	Overwrites destination channel with source channel.
Set	Sets selected channel(s) to Amount.
Add	Adds Amount.
Subtract	Subtracts Amount.
Multiply	Multiplies by factor.
Divide	Divides by factor.
Clamp Min	Clamps selected channel(s) to be ≥ Amount.
Clamp Max	Clamps selected channel(s) to be ≤ Amount.
Truncate	Quantizes using a step derived from Amount.
Contrast	Adjusts contrast around mid-gray based on Amount.

Sources

Source	Channels
RGB	R, G, B
R	Red
G	Green
B	Blue
HSV	H, S, V
H	Hue
S	Saturation
V	Value
Oklab	L, a, b

after node execution, the node saves a preview PNG and pushes a refresh for instant display.

if you find mismatch between preview and output image, make issue on repo.

MIT