Testing with Video Files

The file player allows you to run the entire system without cameras by feeding recorded video files into the shared memory pipeline. This is essential for:

• Initial setup — verify the system works before connecting cameras
• Training operators — practice distance measurement with known jumps
• Tuning motion detection — adjust thresholds using repeatable test data
• Grid line calibration — calibrate anchor points from reference footage
• Development — test code changes without hardware

Step-by-Step: Full Pipeline from Files

1. Prepare Video Files

You need one video file per camera feed. These can be:

• MP4/MKV/AVI recordings from the actual cameras
• Raw YUV420 files captured previously
• Any video file that Media Foundation can decode

2. Determine Frame Offsets

If your three video files were not started at the same moment, you need frame offsets to synchronize them. Find a visible event (e.g., a jumper crossing a reference point) in all three feeds and count the frame difference.

Example: if the same event appears at frame 8167 in feed 0, frame 6015 in feed 1, and frame 5032 in feed 2:

Feed 0 offset: 8167
Feed 1 offset: 6015
Feed 2 offset: 5032

3. Start the File Players

Open three command prompts and run one file player per feed:

bin\fileplayer.exe 0 videos\camera_bottom.mp4 8167
bin\fileplayer.exe 1 videos\camera_middle.mp4 6015
bin\fileplayer.exe 2 videos\camera_top.mp4 5032

Each player writes frames at 60fps into its feed's shared memory buffer.

4. Start Motion Detection

Open three more command prompts:

bin\motion.exe 0 settings.txt
bin\motion.exe 1 settings.txt
bin\motion.exe 2 settings.txt

Or use the controller: click Start All (but do not start capture processes, since file players replace them).

5. Start the Video Generator

bin\videogen.exe settings.txt

6. Start the Viewer

bin\viewer.exe settings.txt

You should now see the merged video output with the ability to scroll through frames and measure distances.

Using the Controller for File Playback

You can also manage file playback through the controller, but you need to start the file players manually from the command line (the controller's Start Capture buttons launch capture.exe, not fileplayer.exe). A typical workflow:

1. Start file players manually in command prompts (Step 3 above)
2. Launch controller.exe settings.txt
3. On the Processes tab, start Motion 0/1/2, VideoGen, and Viewer

Single-Feed Testing

For quick testing with just one camera, you can run a single feed:

bin\fileplayer.exe 1 test_video.mp4
bin\motion.exe 1 settings.txt
bin\viewer.exe settings.txt

The viewer will show whatever is in the output buffer. Without videogen, you can still navigate the raw feed frames.

Looping Playback

The file player exits when it reaches the end of the file. To loop continuously, restart the players. The circular buffer retains the last 520 frames (~8.7 seconds), so there will be a brief gap when the player restarts.

Troubleshooting File Playback

See Also

• File Player — command reference
• Motion Detection Tuning
• Grid Line Calibration
• Quick Start