Nodes/WAS_Extras/WAS Channel Waveform (Parade)
ComfyUI Node

WAS Channel Waveform (Parade)

A colorist's exposure scope, inside ComfyUI

By WASasquatch·Created 3 years ago·Updated 17 days ago· 43
WAS Channel Waveform (Parade)
  • image
  • red_waveform
  • green_waveform
  • blue_waveform
  • rgb_parade
waveform_height512

This node doesn't change your image at all - it looks at it. If you've used a waveform monitor or RGB parade view in DaVinci Resolve, Premiere, or any real color grading tool, this is the same idea: plot each color channel's brightness across the image's horizontal axis, so you can actually see clipping and channel balance instead of eyeballing it on a screen that might be lying to you about brightness or color.

How it works

Feed it an image and it generates four separate visualizations: individual waveforms for red, green, and blue, plus an "RGB parade" - the three channel waveforms shown side by side, which is the standard view professional colorists use to judge white balance and clipping at a glance. A waveform plots pixel brightness (per channel) against horizontal image position, so a flat line pinned at the top of the graph means blown-out highlights in that channel across that part of the frame, and a channel sitting consistently higher or lower than the other two across the whole image is a color cast.

This is purely diagnostic. It's an output node - it doesn't hand a modified image back downstream, just the four scope visualizations for you to look at (typically with a Preview Image node on the output you care about).

The inputs and outputs that matter

  • image (IMAGE) - what you're analyzing.
  • waveform_height (default 512, range 128–2048) - the vertical resolution of the scope images themselves. This is purely about how readable the output is, not a filter setting - raise it if the waveform looks too coarse to read fine detail in.

Four outputs, all IMAGE: red_waveform, green_waveform, blue_waveform, and rgb_parade. For a quick sanity check, the parade view is usually the one worth previewing; the individual channel waveforms are there for when you need to isolate a problem to one specific channel.

How to install it

Via ComfyUI Manager: search "WAS_Extras", install, restart. Manually:

cd ComfyUI/custom_nodes
git clone https://github.com/WASasquatch/WAS_Extras

Restart ComfyUI. No extra dependencies.

Common issues & troubleshooting

You're staring at four images and don't know what you're looking at. Start with rgb_parade. If the three channel traces roughly overlap and stay within the graph's vertical bounds, exposure and white balance are reasonably in check. A trace pinned flat against the top edge means that channel is clipping in that region of the image; a trace that's consistently offset from the other two across the whole frame is a color cast.

This node doesn't fix anything, it just shows a graph. Correct - it's a scope, not a corrector. Pair it with WAS Apply LUT or basic color-correction nodes to actually act on what the waveform is telling you; this node's job ends at diagnosis.

Want to check for over-saturation after a generation. AI images commonly come out oversaturated and high-contrast by default, and that tends to show up here as channels riding high or clipping at the top of the graph - a useful check right after generation, and again after any color-grading pass (a LUT, a sharpen) to confirm you haven't pushed something into clipping.

Waveform image looks too small or blocky to read. That's waveform_height - raise it for a taller, more legible scope image, especially if you're previewing at a small size in the UI.

CategoryWAS/Image/Scopes

Inputs (2)

NameTypeDefaultDescription
imageIMAGEImages to analyze (NHWC).
waveform_heightINT512128–2048Vertical resolution of waveform display (px).

Outputs (4)

NameTypeDescription
red_waveformIMAGE
green_waveformIMAGE
blue_waveformIMAGE
rgb_paradeIMAGE