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Motion Convert Node

Motion Vectors are 2D vectors that represent the displacement in normalized pixel units of a pixel in the current frame to the next frame (forward motion vector), or its displacement from the previous frame (backward motion vector). Motion Vectors can be rendered by a 3D application when dealing with synthetic images, or produced through image analysis when images come from live action footage.

Use the Motion Convert node to convert normalized 2D vectors into absolute vectors that you can work with in Flame.

You can attach a front clip to the node. Attach forward and backward motion data to the forward flow (green) and backward flow (blue) tabs. Output a result, as well a forward and backward flows. You can attach the forward and backward outputs from the Motion Analysis node or import motion data from another source. See Motion Estimation Using Batch Nodes.

Vector Input Type box
  Select whether the vector inputs are Absolute or Normalized.
Maximum Displacement field
  Displays the level of motion displacement in the image. Set to the same value that was set in the 3D application.
Blue Channel Magnitude button
  Enable to use the blue channel as a magnitude multiplication of the maximum displacement value.
Black As No Movement button
  Enable to set black pixels as no movement in the motion vector. When enabled, you can set a threshold value for near-black pixels.
Threshold field
  Displays the level of near-black pixels taken into account in the conversion.

You can also use the Motion Convert node to display motion analysis data as motion vectors. You can view forward and backward motion vectors, and customize the colour and size of the vectors to make them easier to view. The arrow length displays displacement, and the size of the arrowhead indicates the relative speed of the motion.

Forward button
  Displays the forward motion vectors in the Result view.
Backward button
  Displays the backward motion vectors in the Result view.
Arrow colour pots
  Change the display colour of the forward and backward motion vectors.
Grid fields
  Displays the length of the pixel area used to calculate each vector. For example, enter 5 to sample an area of 25 pixels.
Scaling fields
  Displays the size of the motion vectors.
Blend Previous Frame field
  Displays the level of opacity of the current frame, which is overlaid on the previous frame. Set the value to 100 to display the current frame only.