Camera USB Vidgear

This function block provides a flexible USB camera input for live image capture. Use it to scan, select and configure USB cameras, then stream frames into your processing graph. It is designed for continuous capture with simple controls for activation, release and resolution management.

📥 Inputs

Activate Signal Activate the camera and start returning frames (input socket)

Release Signal Release the camera and free resources (input socket)

📤 Outputs

Image Any Current camera frame (output socket)

🕹️ Controls

Scan Connected USB Cameras Scan the system and list available USB cameras

Select USB Camera Dropdown to choose which detected camera to use

Camera Resolution Dropdown to choose a preferred capture resolution

Current Resolution Label showing the active resolution returned by the camera

Open Advanced Setting Opens the camera vendor/system settings dialog when available

Message Area Inline status messages and errors shown to the user

🎨 Features

• Live USB camera capture suitable for production and testing scenarios.

• Easy discovery: scan and pick from connected cameras without leaving the interface.

• Resolution control: select common resolutions and the block shows the actual active resolution.

• Start / stop behavior via Activate Signal and Release Signal to manage resources.

• Graceful handling of temporary stream problems: the block preserves the last good frame, shows informative messages, and will attempt to recover the stream if possible.

• Optional background frame uploader support for asynchronous export or logging (if configured in your environment).

• Visual feedback: current status and helpful messages are displayed in the block UI.

⚙️ How it runs

• Click Scan Connected USB Cameras to populate the camera list, then choose a camera from Select USB Camera.

• Use Camera Resolution to request a preferred width/height; the Current Resolution label shows what the camera actually set.

• When Activate Signal is provided the block starts returning frames on the Image Any output. If the signal is not active, the block continues to hold and return the last captured frame.

• When Release Signal is provided the block stops the camera and frees the resource; the last available frame is still returned until the camera is reactivated.

• If the block encounters repeated blank/corrupted frames or a stream error, it will display an error message and attempt to recover or restart the camera automatically. This prevents silent failures in live scenarios.

📝 Usage Instructions

1. Click Scan Connected USB Cameras to detect cameras.

2. Choose the desired camera using Select USB Camera.

3. Optionally select a resolution from Camera Resolution.

4. Send a Activate Signal to begin receiving frames from the Image Any output.

5. Send a Release Signal when you no longer need the camera to free the device.

💡 Tips and Tricks

• Preview live frames by connecting the Image Any output to the Show Image block for immediate visual feedback.

• To log or save frames, connect the Image Any output to Image Logger, Image Write or Record Video.

• If you need faster processing and can accept lower fidelity, insert Image Resize before heavy processing to reduce compute load.

• Improve detection robustness by inserting simple preprocessing such as Blur, Denoising, or Auto Contrast between the camera output and AI blocks.

• For targeted analysis use Image ROI Select or Image ROI Polygon to crop the scene before detection.

• Combine with AI blocks like Object Detection, Mask Detection, Pose Estimation or Object Detection - Custom to build inspection or analytics pipelines. For tracking use Object_Detection_Tracker after an object detection block.

• To publish results to external systems, route derived numeric/text outputs to MQTT Publish or REST API - Post blocks.

• If you see repeated black frames, try re-scanning the camera list or toggling the Release Signal to force a restart of the selected camera.

🛠️ Troubleshooting

• No cameras listed after scan: confirm the camera is connected, powered and not exclusively used by another application. Re-scan after reconnecting.

• Camera fails to start or stream: check the selected camera in Select USB Camera and try a different resolution in Camera Resolution. Use Release Signal and then re-activate.

• Intermittent black or corrupted frames: the block keeps the last good frame to avoid gaps; if the problem persists, re-scan and re-select the camera or try a different USB port.

• Advanced camera controls not available: some camera vendor dialogs are platform-specific. Use the block’s resolution options or the camera’s system tools when advanced settings are required.

🔗 Example combinations

• Live monitoring: Camera USB Vidgear -> Show Image.

• Recording and post-analysis: Camera USB Vidgear -> Record Video and/or Image Logger; then feed recorded frames into Find Object or Histogram On Line.

• Inspection pipeline: Camera USB Vidgear -> Image ROI Select -> Object Detection -> Object_Detection_Tracker -> Image Write.

Use these combinations to build robust, real-time computer vision flows without touching implementation details.