Histogram Nodes

Tonal analysis. Both nodes show a live histogram of their input in the Properties panel, with draggable window bars that edit their parameters directly.

Histogram

Type id: histogram

Shows the tonal distribution of its input and lets you remap a slice of it in the same node. Read it to see where your values actually sit; drag its window bars to compress them into a band. Left at defaults the remap is an identity pass, so the node is a pure analyzer.

Inputs

• Input (any texture, required): the texture to analyze and remap.

Outputs

• Output (any texture): the remapped image. The remap runs per channel, so a color input stays in color, and the input’s alpha is preserved.

Parameter	Type	Default	Range / Options	Notes
Position	Float	0.5	0.0 to 1.0	Center of the output band. Edited by dragging the histogram window rather than by a slider; no slider row is shown.
Range	Float	1.0	0.0 to 1.0	Width of the output band. Also edited by dragging the histogram window. At 1.0 with Position 0.5 the remap is an identity passthrough.
Midpoint	Float	0.5	0.05 to 0.95	A levels-style midtone control applied before the band compression. 0.5 is neutral; lower brightens midtones, higher darkens them. Shown as a normal slider.
Mode	Choice	Luminance	Luminance, RGB, Red, Green, Blue	Which distribution the Properties histogram plots. Display only; it does not change the output.
Log Scale	Toggle	Off	On / Off	Plots the histogram on a logarithmic vertical scale, so sparse tones stay visible next to a tall spike. Display only.
Clip Warnings	Toggle	On	On / Off	Highlights values crushed to black or blown to white in the histogram display. Display only.

The remapped image is dithered by up to one 8-bit step on the way out. Squeezing an input into a narrow band compresses its own dithering below one output step, and without this a smooth ramp would come back as visible banding on export.

No Mask input.

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The Properties panel showing the live histogram with its draggable window bars, next to a before/after of an image remapped into a narrower tonal band.

Histogram Scan

Type id: histogram_scan

Sweeps a soft threshold window across the tonal range, a contrast-aware alternative to a hard Threshold. Tones below the window go black, tones above go white, and tones inside ramp between the two, which makes it the better tool when you want to slide a mask through a gradient and watch it grow.

Inputs

• Input (any texture, required): the texture to scan.
• Mask (grayscale, optional): where dark, the input passes through unchanged.

Outputs

• Output (grayscale): the resulting mask. The input’s alpha is preserved.

Parameter	Type	Default	Range / Options	Notes
Position	Float	0.5	0.0 to 1.0	Center of the scanned band. Edited by dragging the histogram window; no slider row is shown.
Contrast	Float	0.5	0.0 to 1.0	Width of the band, inverted: at 0 the ramp spans the whole tonal range, at 1 it collapses to a hard binary cut. Also edited by dragging the histogram window.