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Matrix

Adds a user defined matrix to the input allowing you to multiply all or specific channels by the matrix values. You can copy and paste an existing matrix, using the Animation menu, or adjust individual fields manually.

The matrix controls how each pixel in the source image is affected by those around it, for example,

-1	-1	-1
-1	8	-1
-1	-1	-1

produces an edge detection filter (see EdgeDetect) by multiplying the center pixel by 8 and the surrounding pixels by -1, and then adding the nine values together to calculate the new value of the center pixel. This process is repeated for every pixel in the source image to create the output image.

NOTE: Matrix results that fall outside the 0-1 range are clipped.

Inputs and Controls

Connection Type	Connection Name	Function
Input	unnamed	The image to pass through the matrix.

Control (UI)	Knob (Scripting)	Default Value	Function
Matrix Tab
channels	channels	all	The effect is only applied to these channels. If you set this to something other than all or none, you can use the checkboxes on the right to select individual channels.
matrix	matrix	N/A	Defines the matrix used to multiply all or specific channels. You can copy and paste an existing matrix, using the Animation menu, or adjust individual fields manually.
normalize	normalize	disabled	When enabled, the matrix is divided by a constant so that it’s sum is 1 (where possible). This causes the output image to have the same brightness as the source image.
mask	N/A	disabled	Enables the associated mask channel to the right. Disabling this checkbox is the same as setting the channel to none.
mask	maskChannelInput	none	The channel to use as a mask. By default, the effect is limited to the non-black areas of this channel.
inject	inject	disabled	Copies the mask input to the predefined mask.a channel. Injecting the mask allows you to use the same mask further downstream.
invert	invert_mask	disabled	Inverts the use of the mask channel, so that the effect is limited to the non-white areas of the mask.
fringe	fringe	disabled	Blurs the edges of the mask.
mix	mix	1	Dissolves between the original image at 0 and the full effect at 1.