Kinect Azure CHOP
The Kinect Azure CHOP can be used to obtain body tracking information, including joint positions and rotations, and IMU sensor data from a Microsoft Kinect Azure camera.
NOTE: This TOP requires Microsoft Windows 10 April 2018 or newer. An NVIDIA GEFORCE GTX 1070 or better graphics card is required to obtain body tracking data from the camera. Kinect Azure System Requirements
This CHOP requires a Kinect Azure TOP to connect to the camera and to configure the camera's settings. Not all configuration settings support body tracking e.g. Passive IR depth mode.
Use the Max Players parameter to determine how many players you would like the camera to track. The TOP will automatically assign any bodies that are discovered by the device to the available player spaces. Due to the system used to detect player skeletons from the depth camera image, body tracking data can lag multiple frames behind the image data. To more closely synchronize body and image data, use the 'Sync Body Tracking To Image' option on the primary Kinect Azure TOP that is controlling the device (synchronization will increase lag in the image capture).
For a diagram of the joints tracked and their hierarchy, visit Microsoft's Kinect Azure SDK.
Acceleration and rotation data from the camera's IMU sensor can be obtained by enabling the 'IMU Channels' parameter.
Parameters - Kinect Azure Page
active - Enable to disable the capturing of body tracking data. The primary Kinect Azure TOP must also be active to receive data.
Kinect Azure TOP
top - The name of the Kinect Azure TOP that is connected to the camera.
maxplayers - The number of player skeletons that should be tracked by the device. If the camera does not find enough skeletons, then the extra channels will be set to zero.
Relative Bone Rotations
relbonerotations - Include rotation data for all bone in the skeleton. Rotation is measured in degrees around the XYZ axes relative to the bone's parent.
Absolute Bone Rotations
absbonerotations - Include absolute rotation data for all bone in the skeleton. Rotation is measured in degrees around the XYZ axes relative to the world.
bonelengths - Include channels for the length of each bone. A bone's length is the distance between a joint and its parent joint. See the Kinect Azure SDK for a diagram of the joint heirarchy.
World Space Positions
worldspace - Include channels for the bone's absolute world position in meters.
Color Image Positions
colorspace - Include channels for the skeleton positions in UV coordinates of the Color Image.
Depth Image Positions
depthspace - Include channels for the skeleton positions in UV coordinates of the Depth Image.
Aspect Correct UVs
aspectcorrectuv - Scale the image space positions to that they match the aspect ratio of the corresponding camera.
Mirror Image V Positions
flipimagev - Flip the v coordinate of the image space positions so that 0,0 would be in the top-left corner. This was the default behaviour prior to version 2020.44130.
Mirror U Positions
flipskelu - Mirror's the U coordintate of Color Image Positions and Depth Image Positions above which is useful when those images have been flipped in U (x axis flip like a mirror).
confidence - The confidence that the sensor has that a joint's position and rotation is correct. It can be one of the following values:
- 0 - The joint is out of range (too far from the camera)
- 1 - The joint cannot be seen by the sensor and is predicted based on the neighbouring joints
- 2 - Medium confidence. The sensor is reasonably confident of the joint's position/rotation. This is currently the highest level of confidence the sensor will produce.
- 3 - High confidence. Reserved for future use.
imuchans - Include temperature, acceleration and rotation data from the camera's IMU sensor.
Color Image Positions
colorspave - Include channels for the skeleton positions in UV coordinates of the Color Image.
Parameters - Common Page
timeslice - Turning this on forces the channels to be "Time Sliced". A Time Slice is the time between the last cook frame and the current cook frame.
scope - To determine which channels get affected, some CHOPs use a Scope string on the Common page.
Sample Rate Match
srselect - ⊞ - Handle cases where multiple input CHOPs' sample rates are different. When Resampling occurs, the curves are interpolated according to the Interpolation Method Option, or "Linear" if the Interpolate Options are not available.
- Resample At First Input's Rate
first- Use rate of first input to resample others.
- Resample At Maximum Rate
max- Resample to the highest sample rate.
- Resample At Minimum Rate
min- Resample to the lowest sample rate.
- Error If Rates Differ
err- Doesn't accept conflicting sample rates.
exportmethod - ⊞ - This will determine how to connect the CHOP channel to the parameter. Refer to the Export article for more information.
- DAT Table by Index
datindex- Uses the docked DAT table and references the channel via the index of the channel in the CHOP.
- DAT Table by Name
datname- Uses the docked DAT table and references the channel via the name of the channel in the CHOP.
- Channel Name is Path:Parameter
autoname- The channel is the full destination of where to export to, such has
autoexportroot - This path points to the root node where all of the paths that exporting by Channel Name is Path:Parameter are relative to.
exporttable - The DAT used to hold the export information when using the DAT Table Export Methods (See above).
Info CHOP Channels
Extra Information for the Kinect Azure CHOP can be accessed via an Info CHOP.
Common CHOP Info Channels
- start - Start of the CHOP interval in samples.
- length - Number of samples in the CHOP.
- sample_rate - The samplerate of the channels in frames per second.
- num_channels - Number of channels in the CHOP.
- time_slice - 1 if CHOP is Time Slice enabled, 0 otherwise.
- export_sernum - A count of how often the export connections have been updated.
Common Operator Info Channels
- total_cooks - Number of times the operator has cooked since the process started.
- cook_time - Duration of the last cook in milliseconds.
- cook_frame - Frame number when this operator was last cooked relative to the component timeline.
- cook_abs_frame - Frame number when this operator was last cooked relative to the absolute time.
- cook_start_time - Time in milliseconds at which the operator started cooking in the frame it was cooked.
- cook_end_time - Time in milliseconds at which the operator finished cooking in the frame it was cooked.
- cooked_this_frame - 1 if operator was cooked this frame.
- warnings - Number of warnings in this operator if any.
- errors - Number of errors in this operator if any.