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Old network
As of Houdini 20.5, use Copernicus nodes instead of Compositing nodes. Though both networks still exist, the Compositing network is now designated as COP Network - Old
. The Compositing network and its nodes will be deprecated and then removed in a future Houdini release.
This operation defocuses an image similar to a real camera defocus. Unlike blur, it flares the pixel outwards equally. The shape of the flare can be circular, or that of a regular polygon, to model different types of lenses.
Because computer images tend to have extremely bright spots clipped at white, you can boost values above a certain threshold so that they appear brighter than they actually are, mimicking the defocus circles of a bright light source.
Per Pixel Defocus ¶
Defocus can also be used with a matte to control the areas to defocus. When Per Pixel Defocus is on, the amount of defocus applied at each pixel ranges between 0 (matte is black) and the X/Y sizes (matte is white). Values in the matte above white or below black are clamped. This can be used very effectively for depth of field effects (especially in conjunction with a depth map and the Depth of Field COP - see 'Examples').
Masking ¶
This operation may be masked, which restricts the operation to an area of the image. The mask may be inverted, brightened or dimmed.
The mask input is on the side of the node. The label on the connector indicates the plane being used as a mask.
The mask input can also be scaled to fit the output image’s resolution, if they differ. If this node is changing constantly, and the mask is not, it is somewhat faster to put a Scale COP down to do the resize for the mask image. Otherwise, the scale will occur every time this node cooks.
Scoping ¶
This operation may be restricted to certain planes, or components of planes. In addition, the operation may be applied to a subset of frames within the sequence. An image must have both its frame and plane scoped to be modified.
Images that are not modified are passed through, which does not take any memory or processing time.
Parameters ¶
Defocus
The amount of defocusing to apply (in pixels). This is the diameter of the defocus circle (or poly).
Defocus Y
If you would like to specify a different defocus size for the vertical direction, toggle on this parameter (useful for getting a motion blur defocus effect).
Defocus Shape
The shape of the lens’s circle of confusion.
Polygon Edges
If the defocus shape is a polygon, this is the number of edges that the regular polygon has.
Lens Rotation
If the defocus shape is a polygon, you can rotate the polygon shape to any orientation.
Per Pixel Defocus
This option is enabled when a mask is used (Mask tab). It allows you to vary the amount of defocus applied based on the mask brightness.
There is also a tolerance value which quantizes the defocus sizes. This can speed up the per-pixel defocus, especially when the mask is at a high bit depth (like floating point). It is expressed in defocus size; so a tolerance of 0.01 would have 500 distinct defocus levels between 0 and a defocus size of 5 (0, 0.01, 0.02, … 4.99, 5). Higher tolerances produce faster composites, at the expense of image quality. Artifacts generally become noticeable around 0.1.
Add Edge Ring
Adds a brighter ring area around the defocused area, to mimic a real lens.
Ring Size
The portion of the defocused area that will be visible as a bright ring (its proportional thickness). 0 is none, 1 is the entire area. Normally the ring is only a small portion of the defocused area (around 5%, or 0.05).
Ring Intensity
The extra brightness of the ring (0 is none).
Ring Offset
The ring can be biased more to one side of the bloom; a negative value shifts the bloom ring left or down, while a positive value shift the bloom ring right or up.
Boost Intensity of Bright Spots
If on, values about a certain threshold are brightened to produce visible circles.
Boost Threshold
All luminances above this value will be boosted.
Boost Factor
Multiplies the luminance above the threshold to produce the boost. Produces a more gradual boost.
Boost Level
Boosts the luminance above the threshold amount by this value (by adding it to the luminance). Produces more abrupt changes in color, making the defocus shape stand out more from the image.
Mask ¶
A mask can be chosen to limit the effect of the operator to areas defined by the mask. The mask can be taken from the mask input (side input) or from the first input itself.
Effect Amount
If no mask is present, this blends the output with the input by a constant amount (0 = all input, 1 = all output).
If a mask is present, this amount multiplies the mask.
Operation Mask
Selects the mask plane to use as a mask from the mask input. The mask can be selected from:
A mask can be a component of a plane or an entire plane. If a vector plane is supplied as a mask, its components are multiplied by the images' components.
Scalar Mask ('A', 'C.r')
C.r = I.r * M C.g = I.g * M C.b = I.b * M
Vector Mask ('C')
C.r = I.r * M.r C.g = I.g * M.g C.b = I.b * M.b
First Input
Useful for masking the operation to the image’s own alpha plane.
Mask Input
Selects the mask from the side mask input.
Off
Turns off masking, without requiring disconnection of the mask input (useful for temporarily disabling the mask).
Resize Mask to Fit Image
If the mask image is a different resolution than the output image, turning on this parameter will scale the mask to the output image’s resolution.
If this node is changing constantly, and the mask is not, it is somewhat faster to put a Scale COP down to do the resize for the mask image. Otherwise, the scale will occur every time this node cooks.
Invert Mask
Inverts the mask so that all fully 'masked' portions become unmasked. This saves you from inserting an Invert COP after the node with the mask.
Scope ¶
Plane Scope
Specifies the scope for both the RGB components of Color, Alpha, and other planes. The (C)RGBA mask only affects Color components and Alpha. 'C' will toggle all the RGB components.
For planes other than Color and Alpha, the plane name (plus component, if applicable) should be specified in the string field. The pulldown menu can be used to select planes or components present in this node.
A plane is specified by its name. A component is specified by both its plane and component name. The '*' wildcard may be used to scope all extra planes. Any number of planes or components can be specified, separated by spaces.
Examples:
P N.x N.y P N Pz
Frame Scope ¶
Frame Scope
Allows scoping of specific frames in the frame range. This is in addition to the plane scope (so a plane at a certain frame must be both plane scoped and frame scoped to be modified).
All Frames
All frames are scoped.
Inside Range
All frames inside a subrange are scoped.
Outside Range
All frames outside a subrange are scoped.
Even Frames
Even numbered frames are scoped.
Odd Frames
Odd numbered frames are scoped.
Specific Frames
A user-defined list of frames are scoped.
Frame Range
For Inside/Outside range, this parameter specifies the subrange of the sequence to scope (or unscope). This can be edited in Timeline viewer mode (⌃ Ctrl + 2 in viewer).
Frame Dropoff
For Inside/Outside Range, this parameter specifies certain number of frames before and after to slowly ramp up to scoped. The operation will be blended with its input to 'ease in' or 'ease out' the scoping effect over a number of frames. This can be edited in Timeline viewer mode (⌃ Ctrl + 2 in viewer).
Non-scoped Effect
For unscoped frames, this sets the blend factor between the input and modified images. Normally this is zero (use the input image). By setting this to a non-zero value, you can make unscoped frames be 'slightly' unscoped. The value can vary between 0 (unscoped) and 1 (scoped).
Frame List
The frame list for 'Specific Frames'. Frame numbers should be separated by spaces.
Automatically Adjust for Length Changes
If the sequence range changes, enabling this parameter will adjust the subrange and frame dropoff lengths to fit the new range.
Locals ¶
L
Sequence length
S
Start of sequence
E
End of sequence
IL
Input sequence length
SR
Sequence frame rate
NP
Number of planes in sequence
W,H
Width and height of image
I
Image index (0 at start frame)
IT
Image time (0 at start frame)
AI
Current plane array index
PI
Current plane index
PC
Num of channels in current plane
CXRES
Composite Project X resolution
CYRES
Composite Project Y resolution
CPIXA
Composite Project pixel aspect ratio
CDEPTH
Composite Project raster depth
CBP
Composite Project black point
CWP
Composite Project white point
Examples ¶
Basic Example for Defocus compositing node
This example explores various methods of blurring an image using the Defocus COP.
DepthOfField Example for Defocus compositing node
This example demonstrates how the Defocus COP can mimic a depth of field effect using a detailed mask. An image containing point and normal map information is used. This allows a Depth of Field COP to act as a camera, and create a focus mask for the Defocus COP.
See also |