Time stamp stimuli (case 8838)

[JEC]

We had a system a few years ago that was set up like this:

Computer (DirectRT) --serial port--> Black Box ----> Video Recorder
Video Camera--------------------------|

When a new screen or video or stimulus was presented on screen, DirectRT sent a trigger command out the serial port.

Our black box received video from the camera, overlaid timing data & trigger information from DirectRT, then output a composite video signal which contained the original content and the timing data.

Then, using a video recorder or a computer with a video capture card, everything could be lined back up again.

This was built years before in-computer video capture was very stable under Windows.

I wonder if it'd be useful in this situation?

JEC

[cam15]

Hi JEC,

This "black box" sounds like it might work for our purposes. Could you provide more information on the box?

1. Commercial built or lab constructed?

2. What are the capabilities of the box?

3. Did the box send some signal to the video feed or were the video and DirectRT signals combined somehow using the box?

I'd appreciate any further information you could provide. Thanks!

[JEC]

The system is something we've designed in-house.

The black box has two inputs - composite video and an RS232 (serial port) and one output (composite video).

Incoming video then can have arbitrary text overlaid on top of the image in nearly any location.

MediaLab / DirectRT can then send commands through the serial port which display text on different areas of the screen. For example, you might want to include the date, the subject name, or something similar.

Further, the system includes an on-screen timer which matches up with video's timing resolution of 30 frames per second. This timer can be started, stopped and cleared through the serial port. Thus, the computer can send a 'timer go' command when a new stimulus is displayed on screen, and then the on-screen overlay clock will increment on its own until stopped.

Does that help?

[ARLUser]

Hi John,
Are we able to obtain the schematic/parts list for this black box, or is this something we can purchase from Empirisoft?
You state that your black box has a composite video input, so that obviously is not getting the signal from a USB web cam, correct? What type of camera are you using to supply the input signal? The composite video out signal is cabled to what type of video capture card installed in the computer?
arluser

[JEC]

Hi John,
Are we able to obtain the schematic/parts list for this black box, or is this something we can purchase from Empirisoft?
You state that your black box has a composite video input, so that obviously is not getting the signal from a USB web cam, correct? What type of camera are you using to supply the input signal? The composite video out signal is cabled to what type of video capture card installed in the computer?
arluser

Unfortunately, we've not released the source code or schematic diagrams for this system. However, we can ship you something complete, assembled and tested.

This box was designed to use any camera which can output composite video. It was designed well before USB video was possible on Windows, and much earlier than HDMI / HiDef video streams. So if your camera has a yellow output connector that would plug in to a TV or other monitor, you're in business.

Most video capture cards would accept this type of input as well.