Color¶
Split RGB¶
Splits an RGB image into its individual Red, Green, and Blue channels.
Details
Each output is a single-channel grayscale image corresponding to one color plane.
| Direction | Port | Type |
|---|---|---|
| Input | image |
image |
| Output | red |
image |
| Output | green |
image |
| Output | blue |
image |
Merge RGB¶
Merges three single-channel grayscale images into a single RGB image.
Details
Any unconnected channel defaults to zero (black). All connected channels must have the same dimensions.
| Direction | Port | Type |
|---|---|---|
| Input | red |
image |
| Input | green |
image |
| Input | blue |
image |
| Output | image |
image |
RGB to Gray¶
Converts an RGB or RGBA image to a single-channel grayscale image.
Details
Method options:
- Luminosity (Rec.601) — standard broadcast weights (PIL default):
L = 0.299R + 0.587G + 0.114B - Luminosity (Rec.709) — HDTV/sRGB weights used by skimage:
L = 0.2125R + 0.7154G + 0.0721B - Average — simple mean of R, G, B
- Red / Green / Blue — extracts a single colour channel as grayscale
Output is single-channel (L-mode) ImageData.
| Direction | Port | Type |
|---|---|---|
| Input | image |
image |
| Output | image |
image |
Properties: Method
Color Deconvolution¶
Separates staining colours in histology images using colour deconvolution.
Details
Stain matrices prefixed with SK are from scikit-image, CD2 matrices are from ImageJ's Colour Deconvolution 2 plugin.
Output mode:
- Colored — each channel retains the stain's original colour on a white background
- Grayscale — intensity map where brighter = more stain (for quantification)
Third stain completion:
- Ruifrok — Ruifrok/Johnston fallback
- Cross Product — stain-3 = stain-1 x stain-2
- Auto — keep matrix as provided
| Direction | Port | Type |
|---|---|---|
| Input | image |
image |
| Output | ch1 |
image |
| Output | ch2 |
image |
| Output | ch3 |
image |
Properties: Stain Matrix, Third Stain, ``
Channel Colorize¶
Remaps RGB channels to custom colors and composites them.
Details
Each channel can be assigned any color. The node multiplies each channel's grayscale intensity by its chosen color, then additively blends all channels into one RGB output.
Use cases:
- Change DAPI from blue to cyan
- Show two channels in magenta + green for better contrast
| Direction | Port | Type |
|---|---|---|
| Input | image |
image |
| Output | image |
image |
Merge Image¶
Additively blend multiple images into one output.
Details
Connect any number of images to the input port. The node sums all input pixel values and clips to [0, 1]. Useful for combining individually color-adjusted channels into a single composite (e.g. merge ch1 + ch2 + ch4, skipping DAPI).
Works with both grayscale and RGB inputs. Grayscale inputs are broadcast across all 3 RGB channels.
| Direction | Port | Type |
|---|---|---|
| Input | image |
image |
| Output | image |
image |