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How-To Guides

Task-oriented guides for solving specific problems with Quagga2. These assume you have basic familiarity with the library and focus on getting things done.

Configuration & Setup

Configure Barcode Readers

Select which barcode formats to scan (EAN, CODE 128, UPC, etc.) and understand the trade-offs.

Use Debug Flags 🆕

Enable diagnostic output to troubleshoot issues with localization, decoding, or camera setup.

Performance & Quality

Optimize Performance

Improve scanning speed and reduce CPU usage through configuration tuning.

Handle Difficult Barcodes

Techniques for decoding barcodes with poor lighting, damage, rotation, or small size.

Advanced Features

Create External Readers

Build custom barcode decoder plugins to support additional formats.

Camera & Input

Select Specific Camera (Coming Soon)

Choose between front/back cameras on mobile devices or select from multiple USB cameras.

Adjust Camera Settings (Coming Soon)

Control focus, zoom, flash/torch, and other camera parameters.

Drawing & Visualization

Working with Box Coordinates 🆕

Understand how box, boxes, and line coordinates relate to processed vs. original image dimensions, and how to properly scale coordinates for overlay rendering on video elements.

Tips & Best Practices

Tips and Tricks

Practical advice for getting the best results with Quagga2, including camera setup, user experience, and handling results.

Integration

Handle Multiple Barcodes (Coming Soon)

Detect and decode several barcodes in a single frame simultaneously.

Scan in Background (Coming Soon)

Continue scanning while users interact with other UI elements.

Differences from Tutorials

Tutorials are for learning - they’re comprehensive, beginner-friendly, and explain why you’re doing each step.

How-To Guides are for doing - they’re focused, assume knowledge, and show how to accomplish specific goals.

If you’re new to Quagga2, start with Tutorials instead.

Contributing

Have a useful technique or solution to share? We welcome contributions! See the Contributing Guide.


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