Notch Notch Manual 0.9.23
 Light | Dark
Video Feature Emitter

Video Feature Emitter

Eemits particles from feature points of a video.

image

Method #

This node emits particles from an image or video by extracting feature points from the image or video frame. The source supplied may be set directly using the Image attribute, or taken from a node connected via the Video Node attribute. Features are extracted by looking for corners or areas of interest in the video frame that make good tracking points.

If the source is a video the feature points are then tracked through the motion of the video. Tracking can make use of motion vectors if a Video Optical Flow node is connected to the Optical Flow Node input.

The location of emitted particles depends on the way the image is supplied to the emitter. If an image is supplied via the Image attribute or linked from a Video node it will be emitted from a unit plane in the XY axis, combined with the transform from the emitter itself. If an Image Plane node is linked to the emitter’s Video Node input the transform from the Image Plane is used, so the particles will emit at the same location in 3D space as the pixels in the Image Plane, assuming the emitter’s own transform doesn’t offset it.

Requires an image to be supplied via the Image property or the Video Node input to function.

The transformation values of this node will be inherited by its children. Furthermore, Affectors, Shading, and Rendering nodes will only be effective to the particles emit by this emitter.

Parameters

These properties control the 3D transforms of the node. Transforms will generally be inherited by child nodes, although they can be ignored through the Inherit Transform Channels attributes.

ParameterDetails
Position XMove along the local x-axis.
Position YMove along the local y-axis.
Position ZMove along the local z-axis.
Rotation HeadingRotate around the local y-axis.
Rotation PitchRotate around the local x-axis.
Rotation BankRotate around the local z-axis.
Scale XScale along the local x-axis.
Scale YScale along the local y-axis.
Scale ZScale along the local z-axis.

Toggle which transform channels should be inherited from the parent node. By default, all transforms will be inherited.

ParameterDetails
Position XToggle inheritance of the X Position from the parent.
Position YToggle inheritance of the Y Position from the parent.
Position ZToggle inheritance of the Z Position from the parent.
Rotation HeadingToggle inheritance of the Rotation Heading from the parent.
Rotation PitchToggle inheritance of the Rotation Pitch from the parent.
Rotation BankToggle inheritance of the Rotation Bank from the parent.
Scale XToggle inheritance of the X Scale from the parent.
Scale YToggle inheritance of the Y Scale from the parent.
Scale ZToggle inheritance of the Z Scale from the parent.
World Position OnlyInherit the world position from the parent only, rotation and scale will be ignored. Overrides above properties.
Inherit TimeToggle inheritance of time from the parent.

These properties control the core behaviours of the node.

ParameterDetails
ImageOverride the input image with an image selected from the drop down menu.
RandomnessHow much randomness is added in the particles movement.
LifeControl how low long each particle exists for.
Life RandomnessControl the randomness for the life of each particle.
Emission RateWhat percentage of the particles are emitted from the emitter per second.
Max Particle CountSet a maximum particle count for the emitter.
Use ThicknessChange the thickness of the three dimensional area the particles can spawn in. Only functions if ‘Use Thickness’ is on.
Depth VideoModifies the z position of the particles, based on the input video.
Motion Vector VideoSelect a motion vector video to apply to the object.
Motion Vector EffectScales the magnitude of motion vectors when applied to the particles.
Motion Vector BiasControl whether there is a bias towards either axis from the motion vector video.
Avi FPSChange the frames per second the video is played at.
Motion Vector FPSControl the frames per second of the input motion video.
Time OffsetOffset the time the effect is running.
Feature OffsetLimits which parts of the video emit particles.
Feature Minimum DistanceThe minimum allowed distance between generated feature points - prevents too many feature points from being spawned in one place.
Track Edge Features OnlyToggle whether to track edges, or track the whole image.
Edge Detect ThresholdControl the threshold at which the edge can be detected.
Limit Emissions Per PointToggle whether the number of particles that can be emitted per pixel can be limited.
Emissions Area MinControl the minimum area that the particles will be emitted.
Emissions Area MaxControl the maximum area that the particles will be emitted.

These properties control the material the particles use for emission.

ParameterDetails
ColourRGB colour of particles.
DiffuseControl how much the light is scattered from the surface of the object.
EmissivenessControl how much light is emitted by the particle.
Life Colour Affecter WeightControls how much the result of any Life Colour Shading nodes are blended with the particle’s colour.
Particle ScaleScale the size of the particle.
Dof AmountHow much depth of field effects the particles material.
DensityThe density, for use in some simulations.
TemperatureThe density, for use in some simulations.
Cooling RateThe cooling rate, for thermal dynamics simulations.
Density DecayControl the rate of decay in the density.
Fade In TimeWhat percentage through the particles life span the particle fades in.
Fade Out TimeWhat percentage through the particles life span the particle fades out.

Inputs

NameDescriptionTypical Input
Video Nodeimage or video to be used as a source to emit particles from.Video Loader
Optical Flow NodeVideo used to calculate motion for the particles.Optical Flow
Video Feature NodeThe input video feature node.Video Find Features
Colour Control NodesControl the colours of the particles on emission.Colour Ramp
Transform ModifierApply the transforms of another node to this node.Null
Target NodeModifiy the rotations of the node to always direct the z axis towards the input.Null
Local Transform OverrideApply the transforms of another node to this node, relative to its parent.Null

Related Videos