Fix Bulk Image Processing Script

I have a Python script that should perform image transformation—specifically color correction and adjustment focused on brightness and contrast—but it only handles 2 out of 15 images correctly. I’m sharing the current script, a Word document with descriptions and reference images, and an Excel sheet with three live reference URLs that show the exact look I want.

Here’s what I need:

• Review and debug the existing code.
• Implement reliable brightness and contrast adjustment so every image in the batch matches the references.
• Make sure the routine processes an entire folder in one run, with a simple CLI interface (input folder, output folder, overwrite flag).
• Keep the solution in standard Python, using Pillow or OpenCV as needed, and clearly comment any new lines you add.
• Test on my sample set and confirm that all 15 images are processed accurately.

Deliverables
1. Updated .py file ready to run.
2. A concise README listing dependencies and usage.
3. A short change log summarizing the fixes.

When I run `python transform.py --in ./raw --out ./processed`, I should see 15 perfectly corrected images that align with the Word and URL references.