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[HenryZhuHR]

🛠️ PR Summary

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WARNING ⚠️ this PR is very large, summary may not cover all changes.

🌟 Summary (single-line synopsis)

Updated model loading and export functionalities, enhanced multi-backend support, and improved inference efficiency for YOLOv5 models.

📊 Key Changes (bullet points highlighting any major changes)

• Added handling for various file formats and inference backends (TorchScript, ONNX, TensorFlow, etc.).
• Improved model compatibility with PyTorch and ONNX versions and added mechanisms for dynamic axis support.
• Included enhancements and new options for model quantization and optimization to improve inference speed and reduce model size.
• Introduced updates to various model components and utility functions for streamlined operation and maintenance.

🎯 Purpose & Impact (bullet points explaining any benefits and potential impact to users)

• Enhanced Compatibility: Users can seamlessly work across different inference backends and benefit from the simplicity of exporting models to a variety of formats.
• Optimization and Quantization: Provides options for model size reduction and computational efficiency, making it easier to deploy models on resource-constrained devices.
• Dynamic Axis Support: Allows for more flexible model deployment scenarios by accommodating varying input sizes, thus broadening the range of applications.
• Improved Maintainability: Updates and refactors improve the codebase's maintainability, making it easier for developers to introduce new features or fix issues.

[github-actions]

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[github-actions]

👋 Hello @HenryZhuHR, thank you for submitting a YOLOv5 🚀 PR! To allow your work to be integrated as seamlessly as possible, we advise you to:

• ✅ Verify your PR is up-to-date with ultralytics/yolov5 master branch. If your PR is behind you can update your code by clicking the 'Update branch' button or by running git pull and git merge master locally.
• ✅ Verify all YOLOv5 Continuous Integration (CI) checks are passing.
• ✅ Reduce changes to the absolute minimum required for your bug fix or feature addition. "It is not daily increase but daily decrease, hack away the unessential. The closer to the source, the less wastage there is." — Bruce Lee