π On This Page
Module 6: Advanced Computer Vision – See Like AI
Duration: Week 12-13
Difficulty: Advanced
Prerequisites: Module 4 completed
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π― What You’ll Learn
Build AI that can identify objects, detect faces, and understand images like self-driving cars do!
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ποΈ Part 1: ResNet – Going Deeper Without Breaking
The Problem
Deeper networks should be better, but they often perform WORSE!
Why? Gradients vanish (become too small to learn)
ResNet’s Solution: Skip Connections
Regular: Input β Layer1 β Layer2 β Layer3 β Output
ResNet: Input β Layer1 β Layer2 β Layer3 β Output
β_____________β (skip connection!)
Analogy: Like having shortcuts in a maze
- Information can flow directly
- Easier to learn
- Can build 50-100 layer networks!
Project: Build ResNet-18
- 18 layers deep
- Dataset: CIFAR-10 or your own photos
- Goal: 80%+ accuracy
- Training: 1-2 hours
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π¨ Part 2: Data Augmentation – Getting More from Less
The Problem
Need 1000s of images, but only have 100?
Solution: Transform existing images!
Transformations:
1. Flip: Mirror image horizontally
2. Rotate: Turn 10-15 degrees
3. Crop: Random sections
4. Color: Adjust brightness, contrast
5. Noise: Add small random changes
Result: 100 images β 1000s of variations!
Project: Augmentation Pipeline
- Use Albumentations library
- Create 10 variations of each image
- Compare: With vs without augmentation
- Result: 10-20% better accuracy!
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π― Part 3: Object Detection – Finding Things in Images
Classification vs Detection
- Classification: “This is a cat” β
- Detection: “There’s a cat at position (100, 200)” ββ
How YOLO Works (You Only Look Once)
1. Divide image into grid (e.g., 7×7)
2. Each cell predicts:
– What object? (cat, dog, car)
– Where is it? (x, y, width, height)
– How confident? (0-100%)
3. Combine predictions
4. Remove duplicates
Speed: 30+ images per second (real-time!)
Project: Simple Object Detector
- Simplified YOLO
- Dataset: COCO subset
- Task: Draw boxes around objects
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ποΈ Part 4: Vision Transformers – Attention for Images
New Idea
Remember transformers from Module 4? Use them for images!
How:
1. Split image into patches (16×16 pixels each)
2. Treat each patch like a “word”
3. Use transformer attention
4. Predict image class
Project: Mini Vision Transformer
- Small ViT (10M parameters)
- Dataset: CIFAR-10
- Training: 2-3 hours
- Compare: CNN vs Transformer
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β‘ ISL Optimization
1. MobileNet Architecture
- Regular convolution: Expensive
- Depthwise separable: 9x faster, same accuracy!
2. Progressive Resizing
Start: 64x64 images (fast!)
Middle: 128x128 images
End: 256x256 images (best quality)
Result: 2x faster training!
3. INT8 Quantization for Inference
- After training, convert to 8-bit
- Result: 4x faster predictions
4. ONNX Runtime
- Export model to ONNX format
- Use optimized runtime
- Result: 2-3x faster inference on CPU
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π Resources
- CIFAR-10, ImageNet subsets
- COCO dataset (object detection)
- Albumentations library
- OpenCV
- Roboflow (create custom datasets)
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β Learning Checklist
- [ ] Build ResNet with skip connections
- [ ] Create data augmentation pipeline
- [ ] Implement object detector
- [ ] Build vision transformer
- [ ] Apply MobileNet optimizations
- [ ] Use progressive resizing
- [ ] Deploy with ONNX Runtime
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π Next Steps
Learn professional techniques to train faster and better!
π References & Further Reading
Dive deeper with these carefully selected resources:
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π ResNet Paper
by He et al.
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π YOLO: Real-Time Object Detection
by Redmon et al.
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π Vision Transformer Paper
by Dosovitskiy et al.
π Related Topics
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ResNets: Skip Connections Explained -
β
Object Detection: YOLO vs R-CNN -
β
Vision Transformers vs CNNs