Not applicable to __prod_name software.

Video Tracker Acquisition Entity Properties

These settings control how the video tracker acquisition entity processes video frames as they are received from the capture card. The acquisition entity settings are shown on the properties page when a video tracker is selected in the properties tree.


1. Acquisition Entity Name This is the unique name that is used to identify this video tracker acquisition entity. It is the name you chose when you created the acquisition entity.
2.Red Threshold Settings Checking the box next to this setting will enable tracking on red threshold crossings. When enabled, the value specified by the threshold entry box will be will be used for tracking the red components of the video. This value can be any whole number between 0 (every pixel with a red component is used) and 255 (no pixels with a red component are used). Values outside of that range will be set to the closest valid value. Alternatively, you can click the up or down arrows next to the entry box to increase (up) or decrease (down) the threshold. The red value of the pixel is calculated using a pure color algorithm that subtracts the intensity value from the red component of a pixel. When the enable check box is not checked, the threshold entry box will be grayed out. This setting cannot be changed while Cheetah is recording.
3.Green Threshold Settings Checking the box next to this setting will enable tracking on green threshold crossings. When enabled, the value specified by the threshold entry box will be will be used for tracking the green components of the video. This value can be any whole number between 0 (every pixel with a green component is used) and 255 (no pixels with a green component are used). Values outside of that range will be set to the closest valid value. Alternatively, you can click the up or down arrows next to the entry box to increase (up) or decrease (down) the threshold.The green value of the pixel is calculated using a pure color algorithm that subtracts the intensity value from the green component of a pixel. When the enable check box is not checked, the threshold entry box will be grayed out. This setting cannot be changed while Cheetah is recording.
4. Blue Threshold Settings Checking the box next to this setting will enable tracking on blue threshold crossings. When enabled, the value specified by the threshold entry box will be will be used for tracking the blue components of the video. This value can be any whole number between 0 (every pixel with a blue component is used) and 255 (no pixels with a blue component are used). Values outside of that range will be set to the closest valid value. Alternatively, you can click the up or down arrows next to the entry box to increase (up) or decrease (down) the threshold.The blue value of the pixel is calculated using a pure color algorithm that subtracts the intensity value from the blue component of a pixel. When the enable check box is not checked, the threshold entry box will be grayed out. This setting cannot be changed while Cheetah is recording.
5. Intensity Threshold Settings Checking the box next to this setting will enable tracking on intensity threshold crossings. When enabled, the value specified by the threshold entry box will be will be used for tracking the intensity components of the video. This value can be any whole number between 0 (every pixel with any color information is used) and 255 (only pure white pixels will be tracked). Values outside of that range will be set to the closest valid value. Alternatively, you can click the up or down arrows next to the entry box to increase (up) or decrease (down) the threshold.The Intensity value of the pixel is calculated by taking the average of the RGB pixel components. When the enable check box is not checked, the threshold entry box will be grayed out. This setting cannot be changed while Cheetah is recording.
6. Field Estimation Enable Enables or disables field processing of video frames. When this box is checked, Cheetah is In field processing mode. This means that Cheetah will process the even and odd lines of the video frame into separate video records. The odd lines will be timestamped at the start time of the frame, but the even lines will be timestamped at the midpoint between the odd lines and the beginning of the next frame. The timestamp of the even lines is an estimation of the field timestamp. When this box is not checked, Cheetah uses the normal processing mode method of frame processing. In this mode, all lines are processed into a single video record, and the timestamp is the beginning of the frame. This setting cannot be changed when Cheetah is either in acquisition or recording mode.
7. Camera Delay Settings Checking this box enables a static camera delay for adjusting each video record's timestamp inside Cheetah. This is used when the processing delay of the camera is known; does not change; and causes a significant time shift for video relative to neurological data. Every video record will have this value subtracted from its timestamp prior to the record being written to a file. When camera delay is enabled, you can enterany positive whole number or 0, specifying the number of microseconds of delay to be used for each record into the delay entry box. When the camera delay is disabled, the delay entry box will be grayed out, and no adjustment will be made to the video record's timestamp. This setting cannot be changed when Cheetah is either in acquisition or recording mode.
8. Data File Output Setting When this box is checked, all video records will be saved to the file that is shown right beneath this check box. Removing the check next to this setting will disable video record file writing. When file writing is disabled, you will still be able to see visual representations of the records in the video plot, as well as be able to receive records via NetCom. However, no information will be permanently saved while you are recording.
9. Tracking Mode Selection Specifies the tracking mode you wish to use for this video tracker. Cheetah supports the following tracking types:
  1. None: No direction finding or position tracking will be done. The video tracker will simply record transitions above thresholds. All x and y positions and head direction valuesin video records will be 0.
  2. 2 LED : Cheetah will calculate position and direction based on the assumption that there are 2 LEDs of interest. The direction is determined by the color of each of the LEDs along with the direction offset. The LED color and direction offset can be changed by pressing the setup button to show the Direction Finding Configuration window.
  3. HS-54 : Cheetah will assume that you are using a standard HS-54 layout and track direction and position based on that layout. Direction is determined by used the standard HS-54 colors along with the direction offset. The LED color can be viewed and direction offset can be changed by pressing the setup button to show the Direction Finding Configuration window.

Changing the tracking configuration to one that does not correspond to your actual tracking needs can give erroneous direction and position values. This setting cannot be changed while Cheetah is recording.
10. Tracking Mode Setup Clicking this button will show you the Direction Finding Configuration window.
11. Maximum Target Radius This should be used as a last resort for adjusting tracking options. Attempt to adjust the threshold or video settings before modifying this value. The target radius is the maximum number of pixels between two targets to consider them related for position tracking purposes. This value can be adjusted down if you notice that there is noise being included in your position tracking. It can be adjusted up if Cheetah is tracking a smaller target that is not the object you are trying to track.

Example: In 2LED tracking, the right LED is red and the left LED is green, and the LEDs are pretty close together. Someone puts a green marker on one edge of the maze, that now creates a large green target, throwing off the center calculation. If the target radius is small, the new target will not be considered to be related to the red target and the center will be based on the green LED.
There are a couple of exceptions to this rule:
  1. If there are no other green targets within the target radius, the video tracker will use the largest green target it can find for the left LED target.
  2. If the erroneous target is located within the target radius from the red target, it will be used as the green LED target.
This value can be any positive whole number greater or equal to 1 that will be within the video frame. Radius values that would make the target radius larger than the video image are not allowed, and will be adjusted to the maximum allowable radius for the current video image (i.e. if the resolution is 720 x 480, the maximum value is 865). It cannot be changed while Cheetah is in either acquisition or recording mode.
12. Effective Tracker Frame Rate This informational section indicates the current frame rate at which the video tracker is acquiring frames. The video tracker is limited to processing a maximum of 60 frames per second, so selecting a camera frame rate in excess of this will cause the video tracker frame rate to be decreased.
13. Video File Output Enable Checking this box enables video file output using compression to the file specified in the output filebox. This can be done concurrently with standard Cheetah video tracking. When recording is started, Cheetah will begin to compress the live video image, without processing, and save that video to the file specified in the output file box. A subtitle file will be recorded, along with the compressed video, to allow you to view the Cheetah timestamp overlaid over each video frame in any media player that supports subtitles. It is not recommended that you start and stop recording multiple times while recording live video, as it causes the video file to not be playable in some media players. This setting is only available if you are using a video tracking capture card that supports hardware video encoding or using GigE vision cameras. This setting cannot be changed while Cheetah is recording.
14. Compressed Video Output File Name This is the current file that Cheetah is using for video output. Video output is only available if you are using a video tracking capture card that supports hardware video encoding, or using GigE vision cameras.
15. Video Compression Setup There are no current video encoder properties that can be changed, so this button is disabled for Cheetah.