Revert "cv2.imread(img, -1) for IMREAD_UNCHANGED"

[glenn-jocher]

🛠️ PR Summary

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🌟 Summary

Optimized image loading in data processing pipeline.

📊 Key Changes

• Revised the image reading option in cv2.imread() from -1 (IMREAD_UNCHANGED) to default for datasets.py.

🎯 Purpose & Impact

• 🎨 Ensures consistent color channel loading by removing the IMREAD_UNCHANGED flag, which could potentially lead to unexpected behavior if images with alpha channels or non-standard color spaces are loaded.
• 🚀 Potentially improves compatibility across different image types, leading to fewer errors during image preprocessing.
• ☑️ Might impact users dealing with special image formats, but will make the process more robust for the majority of standard RGB/BGR images.