Build an image sample before an annotated dataset
VideoFrame Extractor can help prepare still images for a computer-vision workflow. Choose a local recording, select a meaningful range and sample at a controlled interval. Download the resulting images with timestamped names, then label them in your annotation tool. This workspace does not export YOLO bounding boxes, COCO JSON, class labels or segmentation masks. Those require a separate labeling and validation step.
Sampling decisions affect what the model sees
A one-second interval reduces near-duplicate frames but can miss short events. A smaller interval can show transitions while overrepresenting one scene. Start with a short trial, inspect the images, then decide whether the interval matches the task. Exclude unreadable frames and verify that lighting, backgrounds and object sizes are represented appropriately. Do not assume that a larger number of similar pictures creates a more diverse training set.
Split by source, not only by image name
Adjacent frames from the same recording are strongly related. Randomly placing them across training and evaluation sets can produce an overly optimistic assessment. Track the original recording and requested timestamps outside this tool, and plan splits by an appropriate independent source or scene. Browser timestamp seeking is approximate; use a dedicated decoder if exact frame identity matters. Process short batches within the 120-frame and 96 MB gallery limits, and retain permission to use the footage.
Start with a short test
- Choose a compatible local video and wait for a playable preview.
- Capture one useful moment, or select a short range and interval.
- Compare the actual subject, then download an image or gallery ZIP.
The workspace accepts sources up to 2 GB and 8.3 million decoded pixels per frame. A gallery holds up to 120 images or 96 MB. Seeking depends on the browser and source timing. Keep the source, use media you have permission to process, and check a small output before starting a larger batch.
Questions for this workflow
Can I download YOLO or COCO labels?
No. The ZIP contains images only. Add and validate annotations in a separate dataset tool.
Does the tool automatically remove duplicate frames?
No. Choose an interval and inspect the output. Dataset deduplication and split validation remain separate steps.
Continue your workflow
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