Dataset Playback
Dataset Playback supplies saved images and video frames to Helios so you can test CV scripts without a live capture device. Use it as the workflow’s video source and stop other capture tools first.
Supported Files
- Images: PNG, JPG/JPEG, BMP, WebP, TIF/TIFF.
- Videos: MP4, AVI, MKV, MOV, and WebM, when their codec is supported.
Choose a folder containing the media directly; subfolders are not scanned. Files are sorted by name with numeric ordering. Videos contribute their individual frames to the same playback list.
Use
| Step | Action |
|---|---|
| 1 | Open Dataset Playback and use Browse... to select the folder. |
| 2 | Confirm that frames were found and choose Frame Rate: 30, 60, 120, 144, or 240 FPS. |
| 3 | Start playback, then open a display and start the CV script you want to test. |
| 4 | Use the slider or Previous frame / Next frame buttons to inspect a particular frame. |
| 5 | Enable Auto Fwd and set an interval when frames should advance automatically. |
Frame Rate controls how often the current image is supplied to the workflow. Auto Fwd controls when the selected image changes; these are separate settings. With Auto Fwd off, the current frame repeats until you step or seek. Automatic advancement wraps to the beginning after the last frame.
The interval accepts 1–600,000 milliseconds. This is a dataset testing tool: video frames advance at the configured interval rather than automatically following the video’s original timing. Stop playback before selecting a different folder or frame rate.
Remove an entry from the folder dropdown only after stopping playback. Removing a saved entry does not delete its folder or media files.
Troubleshooting
- No frames found: select the folder containing readable supported files directly.
- Video contributes no frames: check that it opens correctly and uses a supported codec; try exporting a short PNG/JPEG image sequence.
- The same image repeats: enable Auto Fwd or step manually.
- CV has no video: start Dataset Playback first and check Write FPS, then restart the CV tool.
- A large image does not appear: check Output Panel and try resizing the media to a lower resolution.
- Unexpected image: stop other capture sources and confirm the displayed filename/frame position.