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Video Processors

RV2 Video Tracker

RV2 Block Diagram

The RV2 receives triggers from the RZ, processes video frames, and returns tracking information to the RZ for storage and/or further processing. The RV2 must be on the same local network as the PC running Synapse. Its IP address must be set in the Rig Editor.

RV2 Options

RV2 Options

The trigger source can be either an internal clock or an input from another gizmo. The frame number is timestamped and stored to disk. Make sure the frame rate is less than the free run frame rate which is displayed on the RV2 Live tab. Otherwise you will see frames dropped and missing from your video file.

RVM files define the tracking algorithm and the tracked data that the RV2 returns. They are created in RVMap software, which installs with TDT Drivers, and are stored in the configs directory on the RV2. The Filename list contains the RVMs found on your RV2 device. Choose the appropriate one for your experiment.

The buttons next to the list perform the following actions:

Button Action
Open the selected file in RVMap for editing
Refresh the configurations list
Send the selected map file to the RV2 to preview the tracking algorithm on the RV2 screen


Whatever RVM file is selected is also sent to the RV2 when you exit designtime. The RVM Directory allows you to select a local directory of RMV files for offline experiment design when the RV2 is not available.

Each RVM file defines a number of tracked targets. For each Fixed or Relative target defined in the RVM file, positional data consisting of X, Y, and region values is returned to the RZ on each frame. Reference targets also contain heading information.

When an RVM file is selected from the drop-down list, the target information is parsed and the total number of data points is displayed next to the Channel label and the Target Selector drop-down is updated with the list of available tracked targets.

When Enable Output Link is selected, the target information is available for real-time processing by other gizmos. If the RVM file contains a target called 'T1', and 'T1' is selected in the Target Selector, then data sources 'T1X', 'T1Y', 'T1R' can be used by other gizmos for real-time processing. For example, if you want to trigger an event when the subject is in a particular region, you can feed the 'T1R' output to the State Maker gizmo and use it to choose an outcome based on subject position, all in real-time.

All target positional information is output on the AllTracking output link, so if you need to extract more than one target for real-time processing you can connect a Signal Selector gizmo to the AllTracking link and pick off a signal channel for additional real-time processing.

The Tracking Store option saves all target positional data to disk as a Strobe Store when the frame is received. The Selected Target option creates an Epoch Store with information from the target chosen in the Target Selector drop- down.


See the RV2 section of the System 3 Manual for more information about Video Tracker operations and RVMap software.

USB Camera

Camera Block Diagram

The Camera HAL captures images from a USB camera for general subject behavior monitoring. Frames are captured, stored to disk and timestamped in the data block. Camera frames are saved as a DIVX-encoded AVI file in the same folder as your data block, in the form {TANK}_{BLOCK}_{HalName}.avi. The frame numbers are stored in the data tank as epoch events. The AVI file can be used with the OpenScope Video Viewer and annotation tools.


Synapse supports up to two cameras per Rig and frame rates up to 20 fps. For best practice when using two cameras, keep cameras on separate USB Buses. Typically, PCs use separate buses for rear and front accessible USB inputs.


Frame rate is controlled by a software timer and is prone to jitter. For real-time synchronized video capture and tracking, use the RV2.

Adding the HAL

Camera's aren't added to the rig automatically.

To add a camera:

  1. Click Menu, then Edit Rig.

  2. In the Rig Editor, Right-click your system's processor (such as RX or RZ devices), then click Add Cam.

  3. Click OK to close the Rig Editor and update the Processing Tree.

Camera Options

Camera Options

Option Description
Status Shows if camera is connected or not
Resolution Select a screen resolution
Frame Rate Select desired capture rate in fps
Preview On Shows a live stream from the camera in the Options area. The preview can be used to verify correct Camera placement and connection before recording.

Runtime Interface

The runtime tab displays the raw camera video for online monitoring. Please note that high-demand user interface tasks, like resizing windows, can increase jitter.

Runtime Plot with Camera Set to 5 Frames per Second

A subplot is also added to the main runtime multiplot to preview the frame index alongside other plot data.

Improving Performance

If you are having problems with things like dropped frames, we recommend installing the camera drivers to get access to more settings and controls for your camera. Some features like auto-adjust and "RightLight" can cause problems like increased jitter and dropped frames.