Operation
Chooses the channel math operation.
Common choices include Copy, Add, Subtract, Multiply, Divide, Maximum, Minimum and Difference.
← Fusion node reference
Color & ChannelsIntermediate
Channel Booleans
Channel math and copying
Combines, copies and mathematically remaps RGBA channels between foreground and background images.
Channel Booleans
DaVinci Resolve · Fusion
Channel Booleans is a technical compositing node for channel-level operations that are awkward or impossible with normal blend modes.
Overview
What Channel Booleans does
Channel Booleans can copy alpha from one branch to another, add or multiply channels, build technical mattes, invert data or perform boolean-like operations between two images.
It is especially useful when RGB and alpha need to come from different sources. Instead of rebuilding an image, you can preserve the foreground color while replacing its alpha, or create a matte from another branch.
Because channel math can quickly produce values outside the expected range, Channel Booleans is best treated as a deliberate technical node rather than a creative color-correction tool.
Mental model
Think of the node as a channel calculator: Foreground and Background provide RGBA values, and the selected operation determines how each output channel is built.
Common uses
Copy alpha from one image to another
Build a matte from channel data
Multiply or add technical passes
Combine RGB from one source with alpha from another
Create difference or minimum/maximum channel operations
Repair channel layouts in imported assets
Flow anatomy
Inputs & outputs
The port structure shows how this node fits into a Fusion graph.
Foreground
Foreground image placed over the background.
Background
Background image for the composite.
Effect Mask
Limits the operation spatially.
Channel Booleans
Fusion node
Output
Image containing the calculated channel result.
Inspector
Important parameters
Start with these controls before reaching for more complicated workarounds.
Operation: Copy
Uses the Copy operation.
Operation: Add
Uses the Add operation.
Operation: Subtract
Uses the Subtract operation.
Operation: And / Or / Exclusive Or
Uses the And / Or / Exclusive Or operation.
Operation: Multiply
Uses the Multiply operation.
Operation: Divide
Uses the Divide operation.
Operation: Maximum / Minimum
Uses the Maximum / Minimum operation.
Operation: Negative
Uses the Negative operation.
Operation: Solid
Uses the Solid operation.
Operation: Clear
Uses the Clear operation.
Operation: Difference
Uses the Difference operation.
Operation: Signed Add
Uses the Signed Add operation.
To Red
Selects what is written to the output red channel.
To Green
Selects what is written to the output green channel.
To Blue
Selects what is written to the output blue channel.
To Alpha
Selects what is written to the output alpha channel.
Channel Source: Red / Green / Blue / Alpha FG
Provides separate controls for the red, green, blue and alpha channels.
Channel Source: Red / Green / Blue / Alpha BG
Provides separate controls for the red, green, blue and alpha channels.
Channel Source: Hue / Lightness / Saturation
Sets Channel Source to Hue / Lightness / Saturation.
Do Nothing
Leaves the selected destination channel unchanged.
Aux: Enable Extra Channels
Sets Aux to Enable Extra Channels.
To Z Buffer
Routes the selected source channel or value into the Z-buffer output.
To Z Coverage
Writes Z-buffer coverage data to the selected destination.
To Object ID
Assigns the Object ID written to the render passes.
Object IDs provide a clean way to isolate individual 3D objects after rendering.
To Material ID
Assigns the Material ID written to the render passes.
Material IDs can be used later to isolate surfaces in compositing.
To U Texture / To V Texture
Routes UV texture-coordinate data to the selected destination channel.
To X/Y/Z Normal
Routes the X, Y and Z surface-normal components to the selected output channels.
To BG Red / Green / Blue / Alpha
Provides separate controls for the red, green, blue and alpha channels.
To X/Y Vector
Routes the X and Y motion-vector components to the selected output channels.
To X/Y BackVector
Routes the X and Y backward-motion-vector components to the selected output channels.
To X/Y/Z Position
Routes the X, Y and Z position-pass components to the selected output channels.
To X/Y Disparity
Routes the X and Y stereo-disparity components to the selected output channels.
Practical setup
A reliable workflow
- 1
Decide which output channel needs to change.
- 2
Connect Foreground and Background sources.
- 3
Choose the simplest operation that performs the task.
- 4
Set channel mappings deliberately, especially Alpha.
- 5
Inspect RGBA or alpha separately in the Viewer.
- 6
Clamp or normalize later only if the chosen math produces unwanted values.
Typical node chain
Foreground + Background→
Channel Booleans→
Output RGBA
Examples
Where this node fits in real work
Replace alpha
Keep RGB from the foreground while taking alpha from a matte branch.
Foreground RGBMatteChannel BooleansMerge
Technical mask combination
Two mattes are combined using Maximum or Multiply.
Matte AMatte BChannel Booleans
Troubleshooting
Common mistakes
Using channel math without checking alpha separately.
Assuming Copy behaves like a visual Merge.
Adding channels and clipping values above the usable range.
Forgetting which source feeds Foreground versus Background.
Production notes
Practical tips
Name Channel Booleans nodes by purpose, such as CopyAlpha or MultiplyMattes.
Keep channel operations near the branch they repair.
Use a Viewer channel selector to verify R/G/B/A independently.
Related nodes