Upload folder using huggingface_hub
Browse files- README.md +158 -0
- image_processing_eye_gpu.py +1186 -0
- preprocessor_config.json +20 -0
README.md
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| 1 |
+
# EyeCLAHEImageProcessor
|
| 2 |
+
|
| 3 |
+
A GPU-native Hugging Face ImageProcessor for **Color Fundus Photography (CFP)** images, designed for diabetic retinopathy detection and other retinal imaging tasks.
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| 4 |
+
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| 5 |
+
## Features
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| 6 |
+
|
| 7 |
+
- **Eye Region Localization**: Automatically detects and centers on the fundus using gradient-based radial symmetry
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| 8 |
+
- **Smart Cropping**: Border-minimized square crop centered on the detected eye
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| 9 |
+
- **CLAHE Enhancement**: Contrast Limited Adaptive Histogram Equalization for improved visibility
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| 10 |
+
- **Pure PyTorch**: No OpenCV/PIL dependencies at runtime - fully GPU-accelerated
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| 11 |
+
- **Batch Processing**: Efficient batched operations for training pipelines
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| 12 |
+
- **Flexible Input**: Accepts PyTorch tensors, PIL Images, and NumPy arrays
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| 13 |
+
|
| 14 |
+
## Installation
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| 15 |
+
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| 16 |
+
```bash
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| 17 |
+
pip install transformers torch
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| 18 |
+
```
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| 19 |
+
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| 20 |
+
## Quick Start
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| 21 |
+
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| 22 |
+
```python
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| 23 |
+
from transformers import AutoImageProcessor
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| 24 |
+
from PIL import Image
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| 25 |
+
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| 26 |
+
# Load the processor
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| 27 |
+
processor = AutoImageProcessor.from_pretrained("iszt/eye-clahe-processor", trust_remote_code=True)
|
| 28 |
+
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| 29 |
+
# Process a single image
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| 30 |
+
image = Image.open("fundus_image.jpg")
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| 31 |
+
outputs = processor(image, return_tensors="pt")
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| 32 |
+
pixel_values = outputs["pixel_values"] # Shape: (1, 3, 512, 512)
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| 33 |
+
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| 34 |
+
# Process on GPU
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| 35 |
+
outputs = processor(image, return_tensors="pt", device="cuda")
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| 36 |
+
```
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| 37 |
+
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| 38 |
+
## Batch Processing
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| 39 |
+
|
| 40 |
+
```python
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| 41 |
+
import torch
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| 42 |
+
from PIL import Image
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| 43 |
+
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| 44 |
+
# Load multiple images
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| 45 |
+
images = [Image.open(f"image_{i}.jpg") for i in range(8)]
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| 46 |
+
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| 47 |
+
# Process batch
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| 48 |
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outputs = processor(images, return_tensors="pt", device="cuda")
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| 49 |
+
pixel_values = outputs["pixel_values"] # Shape: (8, 3, 512, 512)
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| 50 |
+
```
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| 51 |
+
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| 52 |
+
## With PyTorch Tensors
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| 53 |
+
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| 54 |
+
```python
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| 55 |
+
import torch
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| 56 |
+
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| 57 |
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# Tensor input: (B, C, H, W) or (C, H, W)
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| 58 |
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images = torch.rand(4, 3, 512, 512) # Batch of 4 images
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| 59 |
+
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| 60 |
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outputs = processor(images, return_tensors="pt")
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| 61 |
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```
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| 62 |
+
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| 63 |
+
## Configuration Options
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| 64 |
+
|
| 65 |
+
| Parameter | Default | Description |
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| 66 |
+
|-----------|---------|-------------|
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| 67 |
+
| `size` | 512 | Output image size (square) |
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| 68 |
+
| `do_crop` | true | Enable eye-centered cropping |
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| 69 |
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| `do_clahe` | true | Enable CLAHE contrast enhancement |
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| 70 |
+
| `crop_scale_factor` | 1.1 | Padding around detected eye region |
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| 71 |
+
| `clahe_grid_size` | 8 | CLAHE tile grid size |
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| 72 |
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| `clahe_clip_limit` | 2.0 | CLAHE histogram clip limit |
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| 73 |
+
| `normalization_mode` | "imagenet" | Normalization: "imagenet", "none", or "custom" |
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| 74 |
+
| `min_radius_frac` | 0.1 | Minimum eye radius as fraction of image |
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| 75 |
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| `max_radius_frac` | 1.2 | Maximum eye radius as fraction of image |
|
| 76 |
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| `allow_overflow` | true | Allow crop box beyond image bounds (fills with black) |
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| 77 |
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| `softmax_temperature` | 0.1 | Temperature for eye center detection (higher = smoother) |
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| 78 |
+
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| 79 |
+
## Custom Configuration
|
| 80 |
+
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| 81 |
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```python
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| 82 |
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from transformers import AutoImageProcessor
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| 83 |
+
|
| 84 |
+
processor = AutoImageProcessor.from_pretrained(
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| 85 |
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"iszt/eye-clahe-processor",
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| 86 |
+
trust_remote_code=True,
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| 87 |
+
size=384,
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| 88 |
+
normalization_mode="imagenet",
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| 89 |
+
clahe_clip_limit=3.0,
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| 90 |
+
softmax_temperature=0.3,
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| 91 |
+
)
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| 92 |
+
```
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| 93 |
+
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| 94 |
+
## Processing Pipeline
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| 95 |
+
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| 96 |
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The processor applies the following steps:
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| 97 |
+
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| 98 |
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1. **Input Standardization**: Convert PIL/NumPy/Tensor to (B, C, H, W) float32 tensor in [0, 1]
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| 99 |
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2. **Eye Localization**: Detect fundus center using radial symmetry analysis
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| 100 |
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3. **Radius Estimation**: Determine fundus boundary from radial intensity profiles
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| 101 |
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4. **Crop & Resize**: Extract square region centered on eye, resize to target size
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| 102 |
+
5. **CLAHE**: Apply contrast enhancement in LAB color space (L channel only)
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| 103 |
+
6. **Normalization**: Apply ImageNet normalization (optional)
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| 104 |
+
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| 105 |
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## Use with Vision Models
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| 106 |
+
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| 107 |
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```python
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| 108 |
+
from transformers import AutoImageProcessor, AutoModel
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| 109 |
+
from PIL import Image
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| 110 |
+
|
| 111 |
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# Load processor and model
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| 112 |
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processor = AutoImageProcessor.from_pretrained("iszt/eye-clahe-processor", trust_remote_code=True)
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| 113 |
+
model = AutoModel.from_pretrained("google/vit-base-patch16-224")
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| 114 |
+
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| 115 |
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# Process and run inference
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| 116 |
+
image = Image.open("fundus.jpg")
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| 117 |
+
inputs = processor(image, return_tensors="pt", device="cuda")
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| 118 |
+
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| 119 |
+
# Update normalization for pretrained models
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| 120 |
+
inputs["pixel_values"] = (inputs["pixel_values"] - torch.tensor([0.485, 0.456, 0.406]).view(1,3,1,1).cuda()) / torch.tensor([0.229, 0.224, 0.225]).view(1,3,1,1).cuda()
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| 121 |
+
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| 122 |
+
with torch.no_grad():
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| 123 |
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outputs = model(**inputs)
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| 124 |
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```
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| 125 |
+
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| 126 |
+
## Technical Details
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| 127 |
+
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| 128 |
+
### Eye Center Detection
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| 129 |
+
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| 130 |
+
Uses a gradient-based radial symmetry approach:
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| 131 |
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- Computes Sobel gradients
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| 132 |
+
- Weights pixels by darkness (fundus is typically darker than background)
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| 133 |
+
- Finds center where gradients point inward radially
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| 134 |
+
- Uses soft argmax for sub-pixel accuracy
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| 135 |
+
|
| 136 |
+
### CLAHE Implementation
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| 137 |
+
|
| 138 |
+
Pure PyTorch CLAHE with:
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| 139 |
+
- Proper sRGB to CIE LAB conversion
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| 140 |
+
- Vectorized histogram computation using scatter_add
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| 141 |
+
- Bilinear interpolation between tile CDFs
|
| 142 |
+
- Only modifies L channel, preserving color information
|
| 143 |
+
|
| 144 |
+
## License
|
| 145 |
+
|
| 146 |
+
Apache 2.0
|
| 147 |
+
|
| 148 |
+
## Citation
|
| 149 |
+
|
| 150 |
+
If you use this processor in your research, please cite:
|
| 151 |
+
|
| 152 |
+
```bibtex
|
| 153 |
+
@software{eye_clahe_processor,
|
| 154 |
+
title={EyeCLAHEImageProcessor: GPU-Native Fundus Image Preprocessing},
|
| 155 |
+
year={2026},
|
| 156 |
+
url={https://huggingface.co/iszt/eye-clahe-processor}
|
| 157 |
+
}
|
| 158 |
+
```
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image_processing_eye_gpu.py
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|
| 1 |
+
"""
|
| 2 |
+
GPU-Native Eye Image Processor for Color Fundus Photography (CFP) Images.
|
| 3 |
+
|
| 4 |
+
This module implements a fully PyTorch-based image processor that:
|
| 5 |
+
1. Localizes the eye/fundus region using gradient-based radial symmetry
|
| 6 |
+
2. Crops to a border-minimized square centered on the eye
|
| 7 |
+
3. Applies CLAHE for contrast enhancement
|
| 8 |
+
4. Outputs tensors compatible with Hugging Face vision models
|
| 9 |
+
|
| 10 |
+
Constraints:
|
| 11 |
+
- PyTorch only (no OpenCV, PIL, NumPy in runtime)
|
| 12 |
+
- CUDA-compatible, batch-friendly, deterministic
|
| 13 |
+
"""
|
| 14 |
+
|
| 15 |
+
from typing import Dict, List, Optional, Union
|
| 16 |
+
import math
|
| 17 |
+
|
| 18 |
+
import torch
|
| 19 |
+
import torch.nn.functional as F
|
| 20 |
+
from transformers.image_processing_utils import BaseImageProcessor, BatchFeature
|
| 21 |
+
|
| 22 |
+
# Optional imports for broader input support
|
| 23 |
+
try:
|
| 24 |
+
from PIL import Image
|
| 25 |
+
PIL_AVAILABLE = True
|
| 26 |
+
except ImportError:
|
| 27 |
+
PIL_AVAILABLE = False
|
| 28 |
+
|
| 29 |
+
try:
|
| 30 |
+
import numpy as np
|
| 31 |
+
NUMPY_AVAILABLE = True
|
| 32 |
+
except ImportError:
|
| 33 |
+
NUMPY_AVAILABLE = False
|
| 34 |
+
|
| 35 |
+
|
| 36 |
+
# =============================================================================
|
| 37 |
+
# PHASE 1: Input & Tensor Standardization
|
| 38 |
+
# =============================================================================
|
| 39 |
+
|
| 40 |
+
def _pil_to_tensor(image: "Image.Image") -> torch.Tensor:
|
| 41 |
+
"""Convert PIL Image to tensor (C, H, W) in [0, 1]."""
|
| 42 |
+
if not PIL_AVAILABLE:
|
| 43 |
+
raise ImportError("PIL is required to process PIL Images")
|
| 44 |
+
|
| 45 |
+
# Convert to RGB if necessary
|
| 46 |
+
if image.mode != "RGB":
|
| 47 |
+
image = image.convert("RGB")
|
| 48 |
+
|
| 49 |
+
# Use numpy as intermediate if available, otherwise manual conversion
|
| 50 |
+
if NUMPY_AVAILABLE:
|
| 51 |
+
arr = np.array(image, dtype=np.float32) / 255.0
|
| 52 |
+
# (H, W, C) -> (C, H, W)
|
| 53 |
+
tensor = torch.from_numpy(arr).permute(2, 0, 1)
|
| 54 |
+
else:
|
| 55 |
+
# Manual conversion without numpy
|
| 56 |
+
width, height = image.size
|
| 57 |
+
pixels = list(image.getdata())
|
| 58 |
+
tensor = torch.tensor(pixels, dtype=torch.float32).view(height, width, 3) / 255.0
|
| 59 |
+
tensor = tensor.permute(2, 0, 1)
|
| 60 |
+
|
| 61 |
+
return tensor
|
| 62 |
+
|
| 63 |
+
|
| 64 |
+
def _numpy_to_tensor(arr: "np.ndarray") -> torch.Tensor:
|
| 65 |
+
"""Convert numpy array to tensor (C, H, W) in [0, 1]."""
|
| 66 |
+
if not NUMPY_AVAILABLE:
|
| 67 |
+
raise ImportError("NumPy is required to process numpy arrays")
|
| 68 |
+
|
| 69 |
+
# Handle different array shapes
|
| 70 |
+
if arr.ndim == 2:
|
| 71 |
+
# Grayscale (H, W) -> (1, H, W)
|
| 72 |
+
arr = arr[..., None]
|
| 73 |
+
|
| 74 |
+
if arr.ndim == 3 and arr.shape[-1] in [1, 3, 4]:
|
| 75 |
+
# (H, W, C) -> (C, H, W)
|
| 76 |
+
arr = arr.transpose(2, 0, 1)
|
| 77 |
+
|
| 78 |
+
# Convert to float and normalize
|
| 79 |
+
if arr.dtype == np.uint8:
|
| 80 |
+
arr = arr.astype(np.float32) / 255.0
|
| 81 |
+
elif arr.dtype != np.float32:
|
| 82 |
+
arr = arr.astype(np.float32)
|
| 83 |
+
|
| 84 |
+
return torch.from_numpy(arr.copy())
|
| 85 |
+
|
| 86 |
+
|
| 87 |
+
def standardize_input(
|
| 88 |
+
images: Union[torch.Tensor, List[torch.Tensor], "Image.Image", List["Image.Image"], "np.ndarray", List["np.ndarray"]],
|
| 89 |
+
device: Optional[torch.device] = None,
|
| 90 |
+
) -> torch.Tensor:
|
| 91 |
+
"""
|
| 92 |
+
Convert input images to standardized tensor format.
|
| 93 |
+
|
| 94 |
+
Args:
|
| 95 |
+
images: Input as:
|
| 96 |
+
- torch.Tensor (C,H,W), (B,C,H,W), or list of tensors
|
| 97 |
+
- PIL.Image.Image or list of PIL Images
|
| 98 |
+
- numpy.ndarray (H,W,C), (B,H,W,C), or list of arrays
|
| 99 |
+
device: Target device (defaults to input device or CPU)
|
| 100 |
+
|
| 101 |
+
Returns:
|
| 102 |
+
Tensor of shape (B, C, H, W) in float32, range [0, 1]
|
| 103 |
+
"""
|
| 104 |
+
# Handle single inputs by wrapping in list
|
| 105 |
+
if PIL_AVAILABLE and isinstance(images, Image.Image):
|
| 106 |
+
images = [images]
|
| 107 |
+
if NUMPY_AVAILABLE and isinstance(images, np.ndarray) and images.ndim == 3:
|
| 108 |
+
# Could be single (H,W,C) or batch (B,H,W) grayscale - assume single if last dim is 1-4
|
| 109 |
+
if images.shape[-1] in [1, 3, 4]:
|
| 110 |
+
images = [images]
|
| 111 |
+
|
| 112 |
+
# Convert list inputs to tensors
|
| 113 |
+
if isinstance(images, list):
|
| 114 |
+
converted = []
|
| 115 |
+
for img in images:
|
| 116 |
+
if PIL_AVAILABLE and isinstance(img, Image.Image):
|
| 117 |
+
converted.append(_pil_to_tensor(img))
|
| 118 |
+
elif NUMPY_AVAILABLE and isinstance(img, np.ndarray):
|
| 119 |
+
converted.append(_numpy_to_tensor(img))
|
| 120 |
+
elif isinstance(img, torch.Tensor):
|
| 121 |
+
t = img if img.dim() == 3 else img.squeeze(0)
|
| 122 |
+
converted.append(t)
|
| 123 |
+
else:
|
| 124 |
+
raise TypeError(f"Unsupported image type: {type(img)}")
|
| 125 |
+
images = torch.stack(converted)
|
| 126 |
+
elif NUMPY_AVAILABLE and isinstance(images, np.ndarray):
|
| 127 |
+
# Batch of numpy arrays (B, H, W, C)
|
| 128 |
+
if images.ndim == 4:
|
| 129 |
+
images = images.transpose(0, 3, 1, 2) # (B, C, H, W)
|
| 130 |
+
if images.dtype == np.uint8:
|
| 131 |
+
images = images.astype(np.float32) / 255.0
|
| 132 |
+
images = torch.from_numpy(images.copy())
|
| 133 |
+
|
| 134 |
+
if images.dim() == 3:
|
| 135 |
+
# Add batch dimension: (C, H, W) -> (B, C, H, W)
|
| 136 |
+
images = images.unsqueeze(0)
|
| 137 |
+
|
| 138 |
+
# Move to target device if specified
|
| 139 |
+
if device is not None:
|
| 140 |
+
images = images.to(device)
|
| 141 |
+
|
| 142 |
+
# Convert to float32 and normalize to [0, 1]
|
| 143 |
+
if images.dtype == torch.uint8:
|
| 144 |
+
images = images.float() / 255.0
|
| 145 |
+
elif images.dtype != torch.float32:
|
| 146 |
+
images = images.float()
|
| 147 |
+
|
| 148 |
+
# Clamp to valid range
|
| 149 |
+
images = images.clamp(0.0, 1.0)
|
| 150 |
+
|
| 151 |
+
return images
|
| 152 |
+
|
| 153 |
+
|
| 154 |
+
def rgb_to_grayscale(images: torch.Tensor) -> torch.Tensor:
|
| 155 |
+
"""
|
| 156 |
+
Convert RGB images to grayscale using luminance formula.
|
| 157 |
+
|
| 158 |
+
Y = 0.299 * R + 0.587 * G + 0.114 * B
|
| 159 |
+
|
| 160 |
+
Args:
|
| 161 |
+
images: Tensor of shape (B, 3, H, W)
|
| 162 |
+
|
| 163 |
+
Returns:
|
| 164 |
+
Tensor of shape (B, 1, H, W)
|
| 165 |
+
"""
|
| 166 |
+
# Luminance weights
|
| 167 |
+
weights = torch.tensor([0.299, 0.587, 0.114], device=images.device, dtype=images.dtype)
|
| 168 |
+
weights = weights.view(1, 3, 1, 1)
|
| 169 |
+
|
| 170 |
+
grayscale = (images * weights).sum(dim=1, keepdim=True)
|
| 171 |
+
return grayscale
|
| 172 |
+
|
| 173 |
+
|
| 174 |
+
# =============================================================================
|
| 175 |
+
# PHASE 2: Eye Region Localization (GPU-Safe)
|
| 176 |
+
# =============================================================================
|
| 177 |
+
|
| 178 |
+
def create_sobel_kernels(device: torch.device, dtype: torch.dtype) -> tuple:
|
| 179 |
+
"""
|
| 180 |
+
Create Sobel kernels for gradient computation.
|
| 181 |
+
|
| 182 |
+
Returns:
|
| 183 |
+
Tuple of (sobel_x, sobel_y) kernels, each of shape (1, 1, 3, 3)
|
| 184 |
+
"""
|
| 185 |
+
sobel_x = torch.tensor([
|
| 186 |
+
[-1, 0, 1],
|
| 187 |
+
[-2, 0, 2],
|
| 188 |
+
[-1, 0, 1]
|
| 189 |
+
], device=device, dtype=dtype).view(1, 1, 3, 3)
|
| 190 |
+
|
| 191 |
+
sobel_y = torch.tensor([
|
| 192 |
+
[-1, -2, -1],
|
| 193 |
+
[ 0, 0, 0],
|
| 194 |
+
[ 1, 2, 1]
|
| 195 |
+
], device=device, dtype=dtype).view(1, 1, 3, 3)
|
| 196 |
+
|
| 197 |
+
return sobel_x, sobel_y
|
| 198 |
+
|
| 199 |
+
|
| 200 |
+
def compute_gradients(grayscale: torch.Tensor) -> tuple:
|
| 201 |
+
"""
|
| 202 |
+
Compute image gradients using Sobel filters.
|
| 203 |
+
|
| 204 |
+
Args:
|
| 205 |
+
grayscale: Tensor of shape (B, 1, H, W)
|
| 206 |
+
|
| 207 |
+
Returns:
|
| 208 |
+
Tuple of (grad_x, grad_y, grad_magnitude)
|
| 209 |
+
"""
|
| 210 |
+
sobel_x, sobel_y = create_sobel_kernels(grayscale.device, grayscale.dtype)
|
| 211 |
+
|
| 212 |
+
# Apply Sobel filters with padding to maintain size
|
| 213 |
+
grad_x = F.conv2d(grayscale, sobel_x, padding=1)
|
| 214 |
+
grad_y = F.conv2d(grayscale, sobel_y, padding=1)
|
| 215 |
+
|
| 216 |
+
# Compute gradient magnitude
|
| 217 |
+
grad_magnitude = torch.sqrt(grad_x ** 2 + grad_y ** 2 + 1e-8)
|
| 218 |
+
|
| 219 |
+
return grad_x, grad_y, grad_magnitude
|
| 220 |
+
|
| 221 |
+
|
| 222 |
+
def compute_radial_symmetry_response(
|
| 223 |
+
grayscale: torch.Tensor,
|
| 224 |
+
grad_x: torch.Tensor,
|
| 225 |
+
grad_y: torch.Tensor,
|
| 226 |
+
grad_magnitude: torch.Tensor,
|
| 227 |
+
) -> torch.Tensor:
|
| 228 |
+
"""
|
| 229 |
+
Compute radial symmetry response for circle detection.
|
| 230 |
+
|
| 231 |
+
This weights regions that are:
|
| 232 |
+
1. Dark (low intensity - typical of pupil/iris)
|
| 233 |
+
2. Have strong radial gradients pointing inward
|
| 234 |
+
|
| 235 |
+
Args:
|
| 236 |
+
grayscale: Grayscale image (B, 1, H, W)
|
| 237 |
+
grad_x, grad_y: Gradient components
|
| 238 |
+
grad_magnitude: Gradient magnitude
|
| 239 |
+
|
| 240 |
+
Returns:
|
| 241 |
+
Radial symmetry response map (B, 1, H, W)
|
| 242 |
+
"""
|
| 243 |
+
B, _, H, W = grayscale.shape
|
| 244 |
+
device = grayscale.device
|
| 245 |
+
dtype = grayscale.dtype
|
| 246 |
+
|
| 247 |
+
# Create coordinate grids
|
| 248 |
+
y_coords = torch.arange(H, device=device, dtype=dtype).view(1, 1, H, 1).expand(B, 1, H, W)
|
| 249 |
+
x_coords = torch.arange(W, device=device, dtype=dtype).view(1, 1, 1, W).expand(B, 1, H, W)
|
| 250 |
+
|
| 251 |
+
# Compute center of mass of dark regions as initial estimate
|
| 252 |
+
# Invert intensity so dark regions have high weight
|
| 253 |
+
dark_weight = 1.0 - grayscale
|
| 254 |
+
dark_weight = dark_weight ** 2 # Emphasize darker regions
|
| 255 |
+
|
| 256 |
+
# Normalize weights
|
| 257 |
+
weight_sum = dark_weight.sum(dim=(2, 3), keepdim=True) + 1e-8
|
| 258 |
+
|
| 259 |
+
# Weighted center of mass
|
| 260 |
+
cx_init = (dark_weight * x_coords).sum(dim=(2, 3), keepdim=True) / weight_sum
|
| 261 |
+
cy_init = (dark_weight * y_coords).sum(dim=(2, 3), keepdim=True) / weight_sum
|
| 262 |
+
|
| 263 |
+
# Compute vectors from each pixel to estimated center
|
| 264 |
+
dx_to_center = cx_init - x_coords
|
| 265 |
+
dy_to_center = cy_init - y_coords
|
| 266 |
+
dist_to_center = torch.sqrt(dx_to_center ** 2 + dy_to_center ** 2 + 1e-8)
|
| 267 |
+
|
| 268 |
+
# Normalize direction vectors
|
| 269 |
+
dx_norm = dx_to_center / dist_to_center
|
| 270 |
+
dy_norm = dy_to_center / dist_to_center
|
| 271 |
+
|
| 272 |
+
# Normalize gradient vectors
|
| 273 |
+
grad_norm = grad_magnitude + 1e-8
|
| 274 |
+
gx_norm = grad_x / grad_norm
|
| 275 |
+
gy_norm = grad_y / grad_norm
|
| 276 |
+
|
| 277 |
+
# Radial symmetry: gradient should point toward center
|
| 278 |
+
# Dot product between gradient and direction to center
|
| 279 |
+
radial_alignment = gx_norm * dx_norm + gy_norm * dy_norm
|
| 280 |
+
|
| 281 |
+
# Weight by gradient magnitude and darkness
|
| 282 |
+
response = radial_alignment * grad_magnitude * dark_weight
|
| 283 |
+
|
| 284 |
+
# Apply Gaussian smoothing to get robust response
|
| 285 |
+
kernel_size = max(H, W) // 8
|
| 286 |
+
if kernel_size % 2 == 0:
|
| 287 |
+
kernel_size += 1
|
| 288 |
+
kernel_size = max(kernel_size, 5)
|
| 289 |
+
|
| 290 |
+
sigma = kernel_size / 6.0
|
| 291 |
+
|
| 292 |
+
# Create 1D Gaussian kernel
|
| 293 |
+
x = torch.arange(kernel_size, device=device, dtype=dtype) - kernel_size // 2
|
| 294 |
+
gaussian_1d = torch.exp(-x ** 2 / (2 * sigma ** 2))
|
| 295 |
+
gaussian_1d = gaussian_1d / gaussian_1d.sum()
|
| 296 |
+
|
| 297 |
+
# Separable 2D convolution
|
| 298 |
+
gaussian_1d_h = gaussian_1d.view(1, 1, 1, kernel_size)
|
| 299 |
+
gaussian_1d_v = gaussian_1d.view(1, 1, kernel_size, 1)
|
| 300 |
+
|
| 301 |
+
pad_h = kernel_size // 2
|
| 302 |
+
pad_v = kernel_size // 2
|
| 303 |
+
|
| 304 |
+
response = F.pad(response, (pad_h, pad_h, 0, 0), mode='reflect')
|
| 305 |
+
response = F.conv2d(response, gaussian_1d_h)
|
| 306 |
+
response = F.pad(response, (0, 0, pad_v, pad_v), mode='reflect')
|
| 307 |
+
response = F.conv2d(response, gaussian_1d_v)
|
| 308 |
+
|
| 309 |
+
return response
|
| 310 |
+
|
| 311 |
+
|
| 312 |
+
def soft_argmax_2d(response: torch.Tensor, temperature: float = 0.1) -> tuple:
|
| 313 |
+
"""
|
| 314 |
+
Compute soft argmax to find the center coordinates.
|
| 315 |
+
|
| 316 |
+
Args:
|
| 317 |
+
response: Response map (B, 1, H, W)
|
| 318 |
+
temperature: Softmax temperature (lower = sharper)
|
| 319 |
+
|
| 320 |
+
Returns:
|
| 321 |
+
Tuple of (cx, cy) each of shape (B,)
|
| 322 |
+
"""
|
| 323 |
+
B, _, H, W = response.shape
|
| 324 |
+
device = response.device
|
| 325 |
+
dtype = response.dtype
|
| 326 |
+
|
| 327 |
+
# Flatten spatial dimensions
|
| 328 |
+
response_flat = response.view(B, -1)
|
| 329 |
+
|
| 330 |
+
# Apply softmax with temperature
|
| 331 |
+
weights = F.softmax(response_flat / temperature, dim=1)
|
| 332 |
+
weights = weights.view(B, 1, H, W)
|
| 333 |
+
|
| 334 |
+
# Create coordinate grids
|
| 335 |
+
y_coords = torch.arange(H, device=device, dtype=dtype).view(1, 1, H, 1).expand(B, 1, H, W)
|
| 336 |
+
x_coords = torch.arange(W, device=device, dtype=dtype).view(1, 1, 1, W).expand(B, 1, H, W)
|
| 337 |
+
|
| 338 |
+
# Weighted sum of coordinates
|
| 339 |
+
cx = (weights * x_coords).sum(dim=(2, 3)).squeeze(-1) # (B,)
|
| 340 |
+
cy = (weights * y_coords).sum(dim=(2, 3)).squeeze(-1) # (B,)
|
| 341 |
+
|
| 342 |
+
return cx, cy
|
| 343 |
+
|
| 344 |
+
|
| 345 |
+
def estimate_eye_center(
|
| 346 |
+
images: torch.Tensor,
|
| 347 |
+
softmax_temperature: float = 0.1,
|
| 348 |
+
) -> tuple:
|
| 349 |
+
"""
|
| 350 |
+
Estimate the center of the eye region in each image.
|
| 351 |
+
|
| 352 |
+
Args:
|
| 353 |
+
images: RGB images of shape (B, 3, H, W)
|
| 354 |
+
softmax_temperature: Temperature for soft argmax (lower = sharper peak detection,
|
| 355 |
+
higher = more averaging). Typical range: 0.01-1.0. Default 0.1 works well
|
| 356 |
+
for most fundus images. Use higher values (0.3-0.5) for noisy images.
|
| 357 |
+
|
| 358 |
+
Returns:
|
| 359 |
+
Tuple of (cx, cy) each of shape (B,) in pixel coordinates
|
| 360 |
+
"""
|
| 361 |
+
grayscale = rgb_to_grayscale(images)
|
| 362 |
+
grad_x, grad_y, grad_magnitude = compute_gradients(grayscale)
|
| 363 |
+
response = compute_radial_symmetry_response(grayscale, grad_x, grad_y, grad_magnitude)
|
| 364 |
+
cx, cy = soft_argmax_2d(response, temperature=softmax_temperature)
|
| 365 |
+
|
| 366 |
+
return cx, cy
|
| 367 |
+
|
| 368 |
+
|
| 369 |
+
# =============================================================================
|
| 370 |
+
# PHASE 2.3: Radius Estimation
|
| 371 |
+
# =============================================================================
|
| 372 |
+
|
| 373 |
+
def estimate_radius(
|
| 374 |
+
images: torch.Tensor,
|
| 375 |
+
cx: torch.Tensor,
|
| 376 |
+
cy: torch.Tensor,
|
| 377 |
+
num_radii: int = 100,
|
| 378 |
+
num_angles: int = 36,
|
| 379 |
+
min_radius_frac: float = 0.1,
|
| 380 |
+
max_radius_frac: float = 0.5,
|
| 381 |
+
) -> torch.Tensor:
|
| 382 |
+
"""
|
| 383 |
+
Estimate the radius of the eye region by analyzing radial intensity profiles.
|
| 384 |
+
|
| 385 |
+
Args:
|
| 386 |
+
images: RGB images (B, 3, H, W)
|
| 387 |
+
cx, cy: Center coordinates (B,)
|
| 388 |
+
num_radii: Number of radius samples
|
| 389 |
+
num_angles: Number of angular samples
|
| 390 |
+
min_radius_frac: Minimum radius as fraction of image size
|
| 391 |
+
max_radius_frac: Maximum radius as fraction of image size
|
| 392 |
+
|
| 393 |
+
Returns:
|
| 394 |
+
Estimated radius for each image (B,)
|
| 395 |
+
"""
|
| 396 |
+
B, _, H, W = images.shape
|
| 397 |
+
device = images.device
|
| 398 |
+
dtype = images.dtype
|
| 399 |
+
|
| 400 |
+
grayscale = rgb_to_grayscale(images) # (B, 1, H, W)
|
| 401 |
+
|
| 402 |
+
min_dim = min(H, W)
|
| 403 |
+
min_radius = int(min_radius_frac * min_dim)
|
| 404 |
+
max_radius = int(max_radius_frac * min_dim)
|
| 405 |
+
|
| 406 |
+
# Create radius and angle samples
|
| 407 |
+
radii = torch.linspace(min_radius, max_radius, num_radii, device=device, dtype=dtype)
|
| 408 |
+
angles = torch.linspace(0, 2 * math.pi, num_angles + 1, device=device, dtype=dtype)[:-1]
|
| 409 |
+
|
| 410 |
+
# Create sampling grid: (num_angles, num_radii)
|
| 411 |
+
cos_angles = torch.cos(angles).view(-1, 1) # (num_angles, 1)
|
| 412 |
+
sin_angles = torch.sin(angles).view(-1, 1) # (num_angles, 1)
|
| 413 |
+
|
| 414 |
+
# Offset coordinates from center
|
| 415 |
+
dx = cos_angles * radii # (num_angles, num_radii)
|
| 416 |
+
dy = sin_angles * radii # (num_angles, num_radii)
|
| 417 |
+
|
| 418 |
+
# Compute absolute coordinates for each batch item
|
| 419 |
+
# cx, cy: (B,) -> expand to (B, num_angles, num_radii)
|
| 420 |
+
cx_expanded = cx.view(B, 1, 1).expand(B, num_angles, num_radii)
|
| 421 |
+
cy_expanded = cy.view(B, 1, 1).expand(B, num_angles, num_radii)
|
| 422 |
+
|
| 423 |
+
sample_x = cx_expanded + dx.unsqueeze(0) # (B, num_angles, num_radii)
|
| 424 |
+
sample_y = cy_expanded + dy.unsqueeze(0) # (B, num_angles, num_radii)
|
| 425 |
+
|
| 426 |
+
# Normalize to [-1, 1] for grid_sample
|
| 427 |
+
sample_x_norm = 2.0 * sample_x / (W - 1) - 1.0
|
| 428 |
+
sample_y_norm = 2.0 * sample_y / (H - 1) - 1.0
|
| 429 |
+
|
| 430 |
+
# Create sampling grid: (B, num_angles, num_radii, 2)
|
| 431 |
+
grid = torch.stack([sample_x_norm, sample_y_norm], dim=-1)
|
| 432 |
+
|
| 433 |
+
# Sample intensities
|
| 434 |
+
sampled = F.grid_sample(
|
| 435 |
+
grayscale, grid, mode='bilinear', padding_mode='border', align_corners=True
|
| 436 |
+
) # (B, 1, num_angles, num_radii)
|
| 437 |
+
|
| 438 |
+
# Average over angles to get radial profile
|
| 439 |
+
radial_profile = sampled.mean(dim=2).squeeze(1) # (B, num_radii)
|
| 440 |
+
|
| 441 |
+
# Compute gradient of radial profile (looking for strong negative gradient at iris edge)
|
| 442 |
+
radial_gradient = radial_profile[:, 1:] - radial_profile[:, :-1] # (B, num_radii-1)
|
| 443 |
+
|
| 444 |
+
# Find the radius with strongest negative gradient (edge of iris)
|
| 445 |
+
# Weight by radius to prefer larger circles (avoid pupil boundary)
|
| 446 |
+
radius_weights = torch.linspace(0.5, 1.5, num_radii - 1, device=device, dtype=dtype)
|
| 447 |
+
weighted_gradient = radial_gradient * radius_weights.unsqueeze(0)
|
| 448 |
+
|
| 449 |
+
# Find minimum (strongest negative gradient)
|
| 450 |
+
min_idx = weighted_gradient.argmin(dim=1) # (B,)
|
| 451 |
+
|
| 452 |
+
# Convert index to radius value
|
| 453 |
+
estimated_radius = radii[min_idx + 1] # +1 because gradient has one less element
|
| 454 |
+
|
| 455 |
+
# Clamp to valid range
|
| 456 |
+
estimated_radius = estimated_radius.clamp(min_radius, max_radius)
|
| 457 |
+
|
| 458 |
+
return estimated_radius
|
| 459 |
+
|
| 460 |
+
|
| 461 |
+
# =============================================================================
|
| 462 |
+
# PHASE 3: Border-Minimized Square Crop
|
| 463 |
+
# =============================================================================
|
| 464 |
+
|
| 465 |
+
def compute_crop_box(
|
| 466 |
+
cx: torch.Tensor,
|
| 467 |
+
cy: torch.Tensor,
|
| 468 |
+
radius: torch.Tensor,
|
| 469 |
+
H: int,
|
| 470 |
+
W: int,
|
| 471 |
+
scale_factor: float = 1.1,
|
| 472 |
+
allow_overflow: bool = False,
|
| 473 |
+
) -> tuple:
|
| 474 |
+
"""
|
| 475 |
+
Compute square bounding box for cropping.
|
| 476 |
+
|
| 477 |
+
Args:
|
| 478 |
+
cx, cy: Center coordinates (B,)
|
| 479 |
+
radius: Estimated radius (B,)
|
| 480 |
+
H, W: Image dimensions
|
| 481 |
+
scale_factor: Multiply radius by this factor for padding
|
| 482 |
+
allow_overflow: If True, don't clamp box to image bounds (for pre-cropped images)
|
| 483 |
+
|
| 484 |
+
Returns:
|
| 485 |
+
Tuple of (x1, y1, x2, y2) each of shape (B,)
|
| 486 |
+
"""
|
| 487 |
+
# Compute half side length
|
| 488 |
+
half_side = radius * scale_factor
|
| 489 |
+
|
| 490 |
+
# Initial box centered on detected eye
|
| 491 |
+
x1 = cx - half_side
|
| 492 |
+
y1 = cy - half_side
|
| 493 |
+
x2 = cx + half_side
|
| 494 |
+
y2 = cy + half_side
|
| 495 |
+
|
| 496 |
+
if allow_overflow:
|
| 497 |
+
# Keep the box centered on the eye, don't clamp
|
| 498 |
+
# Out-of-bounds regions will be filled with black during cropping
|
| 499 |
+
return x1, y1, x2, y2
|
| 500 |
+
|
| 501 |
+
# Clamp to image bounds while maintaining square shape
|
| 502 |
+
# If box exceeds bounds, shift it
|
| 503 |
+
x1 = x1.clamp(min=0)
|
| 504 |
+
y1 = y1.clamp(min=0)
|
| 505 |
+
x2 = x2.clamp(max=W - 1)
|
| 506 |
+
y2 = y2.clamp(max=H - 1)
|
| 507 |
+
|
| 508 |
+
# Ensure square by taking minimum side
|
| 509 |
+
side_x = x2 - x1
|
| 510 |
+
side_y = y2 - y1
|
| 511 |
+
side = torch.minimum(side_x, side_y)
|
| 512 |
+
|
| 513 |
+
# Recenter the box
|
| 514 |
+
cx_new = (x1 + x2) / 2
|
| 515 |
+
cy_new = (y1 + y2) / 2
|
| 516 |
+
|
| 517 |
+
x1 = (cx_new - side / 2).clamp(min=0)
|
| 518 |
+
y1 = (cy_new - side / 2).clamp(min=0)
|
| 519 |
+
x2 = x1 + side
|
| 520 |
+
y2 = y1 + side
|
| 521 |
+
|
| 522 |
+
# Final clamp
|
| 523 |
+
x2 = x2.clamp(max=W - 1)
|
| 524 |
+
y2 = y2.clamp(max=H - 1)
|
| 525 |
+
|
| 526 |
+
return x1, y1, x2, y2
|
| 527 |
+
|
| 528 |
+
|
| 529 |
+
def batch_crop_and_resize(
|
| 530 |
+
images: torch.Tensor,
|
| 531 |
+
x1: torch.Tensor,
|
| 532 |
+
y1: torch.Tensor,
|
| 533 |
+
x2: torch.Tensor,
|
| 534 |
+
y2: torch.Tensor,
|
| 535 |
+
output_size: int,
|
| 536 |
+
padding_mode: str = 'border',
|
| 537 |
+
) -> torch.Tensor:
|
| 538 |
+
"""
|
| 539 |
+
Crop and resize images using grid_sample for GPU efficiency.
|
| 540 |
+
|
| 541 |
+
Args:
|
| 542 |
+
images: Input images (B, C, H, W)
|
| 543 |
+
x1, y1, x2, y2: Crop coordinates (B,) - can extend beyond image bounds
|
| 544 |
+
output_size: Output square size
|
| 545 |
+
padding_mode: How to handle out-of-bounds sampling:
|
| 546 |
+
- 'border': repeat edge pixels (default)
|
| 547 |
+
- 'zeros': fill with black (useful for pre-cropped images)
|
| 548 |
+
|
| 549 |
+
Returns:
|
| 550 |
+
Cropped and resized images (B, C, output_size, output_size)
|
| 551 |
+
"""
|
| 552 |
+
B, C, H, W = images.shape
|
| 553 |
+
device = images.device
|
| 554 |
+
dtype = images.dtype
|
| 555 |
+
|
| 556 |
+
# Create output grid coordinates
|
| 557 |
+
out_coords = torch.linspace(0, 1, output_size, device=device, dtype=dtype)
|
| 558 |
+
out_y, out_x = torch.meshgrid(out_coords, out_coords, indexing='ij')
|
| 559 |
+
out_grid = torch.stack([out_x, out_y], dim=-1) # (output_size, output_size, 2)
|
| 560 |
+
out_grid = out_grid.unsqueeze(0).expand(B, -1, -1, -1) # (B, output_size, output_size, 2)
|
| 561 |
+
|
| 562 |
+
# Scale grid to crop coordinates
|
| 563 |
+
# out_grid is in [0, 1], need to map to [x1, x2] and [y1, y2]
|
| 564 |
+
x1 = x1.view(B, 1, 1, 1)
|
| 565 |
+
y1 = y1.view(B, 1, 1, 1)
|
| 566 |
+
x2 = x2.view(B, 1, 1, 1)
|
| 567 |
+
y2 = y2.view(B, 1, 1, 1)
|
| 568 |
+
|
| 569 |
+
# Map [0, 1] to pixel coordinates
|
| 570 |
+
sample_x = x1 + out_grid[..., 0:1] * (x2 - x1)
|
| 571 |
+
sample_y = y1 + out_grid[..., 1:2] * (y2 - y1)
|
| 572 |
+
|
| 573 |
+
# Normalize to [-1, 1] for grid_sample
|
| 574 |
+
sample_x_norm = 2.0 * sample_x / (W - 1) - 1.0
|
| 575 |
+
sample_y_norm = 2.0 * sample_y / (H - 1) - 1.0
|
| 576 |
+
|
| 577 |
+
grid = torch.cat([sample_x_norm, sample_y_norm], dim=-1) # (B, output_size, output_size, 2)
|
| 578 |
+
|
| 579 |
+
# Sample with specified padding mode
|
| 580 |
+
cropped = F.grid_sample(
|
| 581 |
+
images, grid, mode='bilinear', padding_mode=padding_mode, align_corners=True
|
| 582 |
+
)
|
| 583 |
+
|
| 584 |
+
return cropped
|
| 585 |
+
|
| 586 |
+
|
| 587 |
+
# =============================================================================
|
| 588 |
+
# PHASE 4: CLAHE (Torch-Native)
|
| 589 |
+
# =============================================================================
|
| 590 |
+
|
| 591 |
+
def _srgb_to_linear(rgb: torch.Tensor) -> torch.Tensor:
|
| 592 |
+
"""Convert sRGB to linear RGB."""
|
| 593 |
+
threshold = 0.04045
|
| 594 |
+
linear = torch.where(
|
| 595 |
+
rgb <= threshold,
|
| 596 |
+
rgb / 12.92,
|
| 597 |
+
((rgb + 0.055) / 1.055) ** 2.4
|
| 598 |
+
)
|
| 599 |
+
return linear
|
| 600 |
+
|
| 601 |
+
|
| 602 |
+
def _linear_to_srgb(linear: torch.Tensor) -> torch.Tensor:
|
| 603 |
+
"""Convert linear RGB to sRGB."""
|
| 604 |
+
threshold = 0.0031308
|
| 605 |
+
srgb = torch.where(
|
| 606 |
+
linear <= threshold,
|
| 607 |
+
linear * 12.92,
|
| 608 |
+
1.055 * (linear ** (1.0 / 2.4)) - 0.055
|
| 609 |
+
)
|
| 610 |
+
return srgb
|
| 611 |
+
|
| 612 |
+
|
| 613 |
+
def rgb_to_lab(images: torch.Tensor) -> tuple:
|
| 614 |
+
"""
|
| 615 |
+
Convert sRGB images to CIE LAB color space.
|
| 616 |
+
|
| 617 |
+
This is a proper LAB conversion that:
|
| 618 |
+
1. Converts sRGB to linear RGB
|
| 619 |
+
2. Converts linear RGB to XYZ
|
| 620 |
+
3. Converts XYZ to LAB
|
| 621 |
+
|
| 622 |
+
Args:
|
| 623 |
+
images: RGB images (B, C, H, W) in [0, 1] sRGB
|
| 624 |
+
|
| 625 |
+
Returns:
|
| 626 |
+
Tuple of (L, a, b) where:
|
| 627 |
+
- L: Luminance in [0, 1] (normalized from [0, 100])
|
| 628 |
+
- a, b: Chrominance (normalized to roughly [-0.5, 0.5])
|
| 629 |
+
"""
|
| 630 |
+
device = images.device
|
| 631 |
+
dtype = images.dtype
|
| 632 |
+
|
| 633 |
+
# Step 1: sRGB to linear RGB
|
| 634 |
+
linear_rgb = _srgb_to_linear(images)
|
| 635 |
+
|
| 636 |
+
# Step 2: Linear RGB to XYZ (D65 illuminant)
|
| 637 |
+
# RGB to XYZ matrix
|
| 638 |
+
r = linear_rgb[:, 0:1, :, :]
|
| 639 |
+
g = linear_rgb[:, 1:2, :, :]
|
| 640 |
+
b = linear_rgb[:, 2:3, :, :]
|
| 641 |
+
|
| 642 |
+
x = 0.4124564 * r + 0.3575761 * g + 0.1804375 * b
|
| 643 |
+
y = 0.2126729 * r + 0.7151522 * g + 0.0721750 * b
|
| 644 |
+
z = 0.0193339 * r + 0.1191920 * g + 0.9503041 * b
|
| 645 |
+
|
| 646 |
+
# D65 reference white
|
| 647 |
+
xn, yn, zn = 0.95047, 1.0, 1.08883
|
| 648 |
+
|
| 649 |
+
x = x / xn
|
| 650 |
+
y = y / yn
|
| 651 |
+
z = z / zn
|
| 652 |
+
|
| 653 |
+
# Step 3: XYZ to LAB
|
| 654 |
+
delta = 6.0 / 29.0
|
| 655 |
+
delta_cube = delta ** 3
|
| 656 |
+
|
| 657 |
+
def f(t):
|
| 658 |
+
return torch.where(
|
| 659 |
+
t > delta_cube,
|
| 660 |
+
t ** (1.0 / 3.0),
|
| 661 |
+
t / (3.0 * delta ** 2) + 4.0 / 29.0
|
| 662 |
+
)
|
| 663 |
+
|
| 664 |
+
fx = f(x)
|
| 665 |
+
fy = f(y)
|
| 666 |
+
fz = f(z)
|
| 667 |
+
|
| 668 |
+
L = 116.0 * fy - 16.0 # Range [0, 100]
|
| 669 |
+
a = 500.0 * (fx - fy) # Range roughly [-128, 127]
|
| 670 |
+
b_ch = 200.0 * (fy - fz) # Range roughly [-128, 127]
|
| 671 |
+
|
| 672 |
+
# Normalize to convenient ranges for processing
|
| 673 |
+
L = L / 100.0 # [0, 1]
|
| 674 |
+
a = a / 256.0 + 0.5 # Roughly [0, 1]
|
| 675 |
+
b_ch = b_ch / 256.0 + 0.5 # Roughly [0, 1]
|
| 676 |
+
|
| 677 |
+
return L, a, b_ch
|
| 678 |
+
|
| 679 |
+
|
| 680 |
+
def lab_to_rgb(L: torch.Tensor, a: torch.Tensor, b_ch: torch.Tensor) -> torch.Tensor:
|
| 681 |
+
"""
|
| 682 |
+
Convert CIE LAB to sRGB.
|
| 683 |
+
|
| 684 |
+
Args:
|
| 685 |
+
L: Luminance in [0, 1] (normalized from [0, 100])
|
| 686 |
+
a, b_ch: Chrominance (normalized, roughly [0, 1])
|
| 687 |
+
|
| 688 |
+
Returns:
|
| 689 |
+
RGB images (B, 3, H, W) in [0, 1] sRGB
|
| 690 |
+
"""
|
| 691 |
+
# Denormalize
|
| 692 |
+
L_lab = L * 100.0
|
| 693 |
+
a_lab = (a - 0.5) * 256.0
|
| 694 |
+
b_lab = (b_ch - 0.5) * 256.0
|
| 695 |
+
|
| 696 |
+
# LAB to XYZ
|
| 697 |
+
fy = (L_lab + 16.0) / 116.0
|
| 698 |
+
fx = a_lab / 500.0 + fy
|
| 699 |
+
fz = fy - b_lab / 200.0
|
| 700 |
+
|
| 701 |
+
delta = 6.0 / 29.0
|
| 702 |
+
|
| 703 |
+
def f_inv(t):
|
| 704 |
+
return torch.where(
|
| 705 |
+
t > delta,
|
| 706 |
+
t ** 3,
|
| 707 |
+
3.0 * (delta ** 2) * (t - 4.0 / 29.0)
|
| 708 |
+
)
|
| 709 |
+
|
| 710 |
+
# D65 reference white
|
| 711 |
+
xn, yn, zn = 0.95047, 1.0, 1.08883
|
| 712 |
+
|
| 713 |
+
x = xn * f_inv(fx)
|
| 714 |
+
y = yn * f_inv(fy)
|
| 715 |
+
z = zn * f_inv(fz)
|
| 716 |
+
|
| 717 |
+
# XYZ to linear RGB
|
| 718 |
+
r = 3.2404542 * x - 1.5371385 * y - 0.4985314 * z
|
| 719 |
+
g = -0.9692660 * x + 1.8760108 * y + 0.0415560 * z
|
| 720 |
+
b = 0.0556434 * x - 0.2040259 * y + 1.0572252 * z
|
| 721 |
+
|
| 722 |
+
linear_rgb = torch.cat([r, g, b], dim=1)
|
| 723 |
+
|
| 724 |
+
# Clamp before gamma correction to avoid NaN from negative values
|
| 725 |
+
linear_rgb = linear_rgb.clamp(0.0, 1.0)
|
| 726 |
+
|
| 727 |
+
# Linear RGB to sRGB
|
| 728 |
+
srgb = _linear_to_srgb(linear_rgb)
|
| 729 |
+
|
| 730 |
+
return srgb.clamp(0.0, 1.0)
|
| 731 |
+
|
| 732 |
+
|
| 733 |
+
def compute_histogram(
|
| 734 |
+
tensor: torch.Tensor,
|
| 735 |
+
num_bins: int = 256,
|
| 736 |
+
) -> torch.Tensor:
|
| 737 |
+
"""
|
| 738 |
+
Compute histogram for a batch of single-channel images.
|
| 739 |
+
|
| 740 |
+
Args:
|
| 741 |
+
tensor: Input tensor (B, 1, H, W) with values in [0, 1]
|
| 742 |
+
num_bins: Number of histogram bins
|
| 743 |
+
|
| 744 |
+
Returns:
|
| 745 |
+
Histograms (B, num_bins)
|
| 746 |
+
"""
|
| 747 |
+
B = tensor.shape[0]
|
| 748 |
+
device = tensor.device
|
| 749 |
+
dtype = tensor.dtype
|
| 750 |
+
|
| 751 |
+
# Flatten spatial dimensions
|
| 752 |
+
flat = tensor.view(B, -1) # (B, H*W)
|
| 753 |
+
|
| 754 |
+
# Bin indices
|
| 755 |
+
bin_indices = (flat * (num_bins - 1)).long().clamp(0, num_bins - 1)
|
| 756 |
+
|
| 757 |
+
# Compute histogram using scatter_add
|
| 758 |
+
histograms = torch.zeros(B, num_bins, device=device, dtype=dtype)
|
| 759 |
+
ones = torch.ones_like(flat, dtype=dtype)
|
| 760 |
+
|
| 761 |
+
for i in range(B):
|
| 762 |
+
histograms[i] = histograms[i].scatter_add(0, bin_indices[i], ones[i])
|
| 763 |
+
|
| 764 |
+
return histograms
|
| 765 |
+
|
| 766 |
+
|
| 767 |
+
def clahe_single_tile(
|
| 768 |
+
tile: torch.Tensor,
|
| 769 |
+
clip_limit: float,
|
| 770 |
+
num_bins: int = 256,
|
| 771 |
+
) -> torch.Tensor:
|
| 772 |
+
"""
|
| 773 |
+
Apply CLAHE to a single tile.
|
| 774 |
+
|
| 775 |
+
Args:
|
| 776 |
+
tile: Input tile (B, 1, tile_h, tile_w)
|
| 777 |
+
clip_limit: Histogram clip limit
|
| 778 |
+
num_bins: Number of histogram bins
|
| 779 |
+
|
| 780 |
+
Returns:
|
| 781 |
+
CDF lookup table (B, num_bins)
|
| 782 |
+
"""
|
| 783 |
+
B, _, tile_h, tile_w = tile.shape
|
| 784 |
+
device = tile.device
|
| 785 |
+
dtype = tile.dtype
|
| 786 |
+
num_pixels = tile_h * tile_w
|
| 787 |
+
|
| 788 |
+
# Compute histogram
|
| 789 |
+
hist = compute_histogram(tile, num_bins) # (B, num_bins)
|
| 790 |
+
|
| 791 |
+
# Clip histogram
|
| 792 |
+
clip_value = clip_limit * num_pixels / num_bins
|
| 793 |
+
excess = (hist - clip_value).clamp(min=0).sum(dim=1, keepdim=True) # (B, 1)
|
| 794 |
+
hist = hist.clamp(max=clip_value)
|
| 795 |
+
|
| 796 |
+
# Redistribute excess uniformly
|
| 797 |
+
redistribution = excess / num_bins
|
| 798 |
+
hist = hist + redistribution
|
| 799 |
+
|
| 800 |
+
# Compute CDF
|
| 801 |
+
cdf = hist.cumsum(dim=1) # (B, num_bins)
|
| 802 |
+
|
| 803 |
+
# Normalize CDF to [0, 1]
|
| 804 |
+
cdf_min = cdf[:, 0:1]
|
| 805 |
+
cdf_max = cdf[:, -1:]
|
| 806 |
+
cdf = (cdf - cdf_min) / (cdf_max - cdf_min + 1e-8)
|
| 807 |
+
|
| 808 |
+
return cdf
|
| 809 |
+
|
| 810 |
+
|
| 811 |
+
def apply_clahe_vectorized(
|
| 812 |
+
images: torch.Tensor,
|
| 813 |
+
grid_size: int = 8,
|
| 814 |
+
clip_limit: float = 2.0,
|
| 815 |
+
num_bins: int = 256,
|
| 816 |
+
) -> torch.Tensor:
|
| 817 |
+
"""
|
| 818 |
+
Vectorized CLAHE implementation (more efficient for GPU).
|
| 819 |
+
|
| 820 |
+
Args:
|
| 821 |
+
images: Input images (B, C, H, W)
|
| 822 |
+
grid_size: Number of tiles in each dimension
|
| 823 |
+
clip_limit: Histogram clip limit
|
| 824 |
+
num_bins: Number of histogram bins
|
| 825 |
+
|
| 826 |
+
Returns:
|
| 827 |
+
CLAHE-enhanced images (B, C, H, W)
|
| 828 |
+
"""
|
| 829 |
+
B, C, H, W = images.shape
|
| 830 |
+
device = images.device
|
| 831 |
+
dtype = images.dtype
|
| 832 |
+
|
| 833 |
+
# Work on luminance only
|
| 834 |
+
if C == 3:
|
| 835 |
+
L, a, b_ch = rgb_to_lab(images)
|
| 836 |
+
else:
|
| 837 |
+
L = images.clone()
|
| 838 |
+
a = b_ch = None
|
| 839 |
+
|
| 840 |
+
# Ensure divisibility
|
| 841 |
+
pad_h = (grid_size - H % grid_size) % grid_size
|
| 842 |
+
pad_w = (grid_size - W % grid_size) % grid_size
|
| 843 |
+
|
| 844 |
+
if pad_h > 0 or pad_w > 0:
|
| 845 |
+
L_padded = F.pad(L, (0, pad_w, 0, pad_h), mode='reflect')
|
| 846 |
+
else:
|
| 847 |
+
L_padded = L
|
| 848 |
+
|
| 849 |
+
_, _, H_pad, W_pad = L_padded.shape
|
| 850 |
+
tile_h = H_pad // grid_size
|
| 851 |
+
tile_w = W_pad // grid_size
|
| 852 |
+
|
| 853 |
+
# Reshape into tiles: (B, 1, grid_size, tile_h, grid_size, tile_w)
|
| 854 |
+
L_tiles = L_padded.view(B, 1, grid_size, tile_h, grid_size, tile_w)
|
| 855 |
+
L_tiles = L_tiles.permute(0, 2, 4, 1, 3, 5) # (B, grid_size, grid_size, 1, tile_h, tile_w)
|
| 856 |
+
L_tiles = L_tiles.reshape(B * grid_size * grid_size, 1, tile_h, tile_w)
|
| 857 |
+
|
| 858 |
+
# Compute histograms for all tiles at once
|
| 859 |
+
num_pixels = tile_h * tile_w
|
| 860 |
+
flat = L_tiles.view(B * grid_size * grid_size, -1)
|
| 861 |
+
bin_indices = (flat * (num_bins - 1)).long().clamp(0, num_bins - 1)
|
| 862 |
+
|
| 863 |
+
# Vectorized histogram computation
|
| 864 |
+
histograms = torch.zeros(B * grid_size * grid_size, num_bins, device=device, dtype=dtype)
|
| 865 |
+
histograms.scatter_add_(1, bin_indices, torch.ones_like(flat))
|
| 866 |
+
|
| 867 |
+
# Clip and redistribute
|
| 868 |
+
clip_value = clip_limit * num_pixels / num_bins
|
| 869 |
+
excess = (histograms - clip_value).clamp(min=0).sum(dim=1, keepdim=True)
|
| 870 |
+
histograms = histograms.clamp(max=clip_value)
|
| 871 |
+
histograms = histograms + excess / num_bins
|
| 872 |
+
|
| 873 |
+
# Compute CDFs
|
| 874 |
+
cdfs = histograms.cumsum(dim=1)
|
| 875 |
+
cdf_min = cdfs[:, 0:1]
|
| 876 |
+
cdf_max = cdfs[:, -1:]
|
| 877 |
+
cdfs = (cdfs - cdf_min) / (cdf_max - cdf_min + 1e-8)
|
| 878 |
+
|
| 879 |
+
# Reshape CDFs: (B, grid_size, grid_size, num_bins)
|
| 880 |
+
cdfs = cdfs.view(B, grid_size, grid_size, num_bins)
|
| 881 |
+
|
| 882 |
+
# Create coordinate grids for interpolation
|
| 883 |
+
y_coords = torch.arange(H_pad, device=device, dtype=dtype)
|
| 884 |
+
x_coords = torch.arange(W_pad, device=device, dtype=dtype)
|
| 885 |
+
|
| 886 |
+
# Map to tile coordinates (centered on tiles)
|
| 887 |
+
tile_y = (y_coords + 0.5) / tile_h - 0.5
|
| 888 |
+
tile_x = (x_coords + 0.5) / tile_w - 0.5
|
| 889 |
+
|
| 890 |
+
tile_y = tile_y.clamp(0, grid_size - 1.001)
|
| 891 |
+
tile_x = tile_x.clamp(0, grid_size - 1.001)
|
| 892 |
+
|
| 893 |
+
# Integer indices and weights
|
| 894 |
+
ty0 = tile_y.long().clamp(0, grid_size - 2)
|
| 895 |
+
tx0 = tile_x.long().clamp(0, grid_size - 2)
|
| 896 |
+
ty1 = (ty0 + 1).clamp(max=grid_size - 1)
|
| 897 |
+
tx1 = (tx0 + 1).clamp(max=grid_size - 1)
|
| 898 |
+
|
| 899 |
+
wy = (tile_y - ty0.float()).view(1, H_pad, 1, 1)
|
| 900 |
+
wx = (tile_x - tx0.float()).view(1, 1, W_pad, 1)
|
| 901 |
+
|
| 902 |
+
# Get bin indices for all pixels
|
| 903 |
+
bin_idx = (L_padded * (num_bins - 1)).long().clamp(0, num_bins - 1) # (B, 1, H_pad, W_pad)
|
| 904 |
+
bin_idx = bin_idx.squeeze(1) # (B, H_pad, W_pad)
|
| 905 |
+
|
| 906 |
+
# Gather CDF values for each corner
|
| 907 |
+
# We need cdfs[b, ty, tx, bin_idx[b, y, x]] for all combinations
|
| 908 |
+
|
| 909 |
+
# Expand indices for gathering
|
| 910 |
+
b_idx = torch.arange(B, device=device).view(B, 1, 1).expand(B, H_pad, W_pad)
|
| 911 |
+
ty0_exp = ty0.view(1, H_pad, 1).expand(B, H_pad, W_pad)
|
| 912 |
+
ty1_exp = ty1.view(1, H_pad, 1).expand(B, H_pad, W_pad)
|
| 913 |
+
tx0_exp = tx0.view(1, 1, W_pad).expand(B, H_pad, W_pad)
|
| 914 |
+
tx1_exp = tx1.view(1, 1, W_pad).expand(B, H_pad, W_pad)
|
| 915 |
+
|
| 916 |
+
# Gather using advanced indexing
|
| 917 |
+
v00 = cdfs[b_idx, ty0_exp, tx0_exp, bin_idx] # (B, H_pad, W_pad)
|
| 918 |
+
v01 = cdfs[b_idx, ty0_exp, tx1_exp, bin_idx]
|
| 919 |
+
v10 = cdfs[b_idx, ty1_exp, tx0_exp, bin_idx]
|
| 920 |
+
v11 = cdfs[b_idx, ty1_exp, tx1_exp, bin_idx]
|
| 921 |
+
|
| 922 |
+
# Bilinear interpolation
|
| 923 |
+
wy = wy.squeeze(-1) # (1, H_pad, 1)
|
| 924 |
+
wx = wx.squeeze(-1) # (1, 1, W_pad)
|
| 925 |
+
|
| 926 |
+
L_out = (1 - wy) * (1 - wx) * v00 + (1 - wy) * wx * v01 + wy * (1 - wx) * v10 + wy * wx * v11
|
| 927 |
+
L_out = L_out.unsqueeze(1) # (B, 1, H_pad, W_pad)
|
| 928 |
+
|
| 929 |
+
# Remove padding
|
| 930 |
+
if pad_h > 0 or pad_w > 0:
|
| 931 |
+
L_out = L_out[:, :, :H, :W]
|
| 932 |
+
|
| 933 |
+
# Convert back to RGB
|
| 934 |
+
if C == 3:
|
| 935 |
+
output = lab_to_rgb(L_out, a, b_ch)
|
| 936 |
+
else:
|
| 937 |
+
output = L_out
|
| 938 |
+
|
| 939 |
+
return output
|
| 940 |
+
|
| 941 |
+
|
| 942 |
+
# =============================================================================
|
| 943 |
+
# PHASE 5: Resize & Normalization
|
| 944 |
+
# =============================================================================
|
| 945 |
+
|
| 946 |
+
# ImageNet normalization constants
|
| 947 |
+
IMAGENET_MEAN = [0.485, 0.456, 0.406]
|
| 948 |
+
IMAGENET_STD = [0.229, 0.224, 0.225]
|
| 949 |
+
|
| 950 |
+
|
| 951 |
+
def resize_images(
|
| 952 |
+
images: torch.Tensor,
|
| 953 |
+
size: int,
|
| 954 |
+
mode: str = 'bilinear',
|
| 955 |
+
antialias: bool = True,
|
| 956 |
+
) -> torch.Tensor:
|
| 957 |
+
"""
|
| 958 |
+
Resize images to target size.
|
| 959 |
+
|
| 960 |
+
Args:
|
| 961 |
+
images: Input images (B, C, H, W)
|
| 962 |
+
size: Target size (square)
|
| 963 |
+
mode: Interpolation mode
|
| 964 |
+
antialias: Whether to use antialiasing
|
| 965 |
+
|
| 966 |
+
Returns:
|
| 967 |
+
Resized images (B, C, size, size)
|
| 968 |
+
"""
|
| 969 |
+
return F.interpolate(
|
| 970 |
+
images,
|
| 971 |
+
size=(size, size),
|
| 972 |
+
mode=mode,
|
| 973 |
+
align_corners=False if mode in ['bilinear', 'bicubic'] else None,
|
| 974 |
+
antialias=antialias if mode in ['bilinear', 'bicubic'] else False,
|
| 975 |
+
)
|
| 976 |
+
|
| 977 |
+
|
| 978 |
+
def normalize_images(
|
| 979 |
+
images: torch.Tensor,
|
| 980 |
+
mean: Optional[List[float]] = None,
|
| 981 |
+
std: Optional[List[float]] = None,
|
| 982 |
+
mode: str = 'imagenet',
|
| 983 |
+
) -> torch.Tensor:
|
| 984 |
+
"""
|
| 985 |
+
Normalize images.
|
| 986 |
+
|
| 987 |
+
Args:
|
| 988 |
+
images: Input images (B, C, H, W) in [0, 1]
|
| 989 |
+
mean: Custom mean (per channel)
|
| 990 |
+
std: Custom std (per channel)
|
| 991 |
+
mode: 'imagenet', 'none', or 'custom'
|
| 992 |
+
|
| 993 |
+
Returns:
|
| 994 |
+
Normalized images
|
| 995 |
+
"""
|
| 996 |
+
if mode == 'none':
|
| 997 |
+
return images
|
| 998 |
+
|
| 999 |
+
if mode == 'imagenet':
|
| 1000 |
+
mean = IMAGENET_MEAN
|
| 1001 |
+
std = IMAGENET_STD
|
| 1002 |
+
elif mode == 'custom':
|
| 1003 |
+
if mean is None or std is None:
|
| 1004 |
+
raise ValueError("Custom mode requires mean and std")
|
| 1005 |
+
else:
|
| 1006 |
+
raise ValueError(f"Unknown normalization mode: {mode}")
|
| 1007 |
+
|
| 1008 |
+
device = images.device
|
| 1009 |
+
dtype = images.dtype
|
| 1010 |
+
|
| 1011 |
+
mean_tensor = torch.tensor(mean, device=device, dtype=dtype).view(1, -1, 1, 1)
|
| 1012 |
+
std_tensor = torch.tensor(std, device=device, dtype=dtype).view(1, -1, 1, 1)
|
| 1013 |
+
|
| 1014 |
+
return (images - mean_tensor) / std_tensor
|
| 1015 |
+
|
| 1016 |
+
|
| 1017 |
+
# =============================================================================
|
| 1018 |
+
# PHASE 6: Hugging Face ImageProcessor Integration
|
| 1019 |
+
# =============================================================================
|
| 1020 |
+
|
| 1021 |
+
class EyeCLAHEImageProcessor(BaseImageProcessor):
|
| 1022 |
+
"""
|
| 1023 |
+
GPU-native image processor for Color Fundus Photography (CFP) images.
|
| 1024 |
+
|
| 1025 |
+
This processor:
|
| 1026 |
+
1. Localizes the eye region using gradient-based radial symmetry
|
| 1027 |
+
2. Crops to a border-minimized square centered on the eye
|
| 1028 |
+
3. Applies CLAHE for contrast enhancement
|
| 1029 |
+
4. Resizes and normalizes for vision model input
|
| 1030 |
+
|
| 1031 |
+
All operations are implemented in pure PyTorch and are CUDA-compatible.
|
| 1032 |
+
"""
|
| 1033 |
+
|
| 1034 |
+
model_input_names = ["pixel_values"]
|
| 1035 |
+
|
| 1036 |
+
def __init__(
|
| 1037 |
+
self,
|
| 1038 |
+
size: int = 224,
|
| 1039 |
+
crop_scale_factor: float = 1.1,
|
| 1040 |
+
clahe_grid_size: int = 8,
|
| 1041 |
+
clahe_clip_limit: float = 2.0,
|
| 1042 |
+
normalization_mode: str = "imagenet",
|
| 1043 |
+
custom_mean: Optional[List[float]] = None,
|
| 1044 |
+
custom_std: Optional[List[float]] = None,
|
| 1045 |
+
do_clahe: bool = True,
|
| 1046 |
+
do_crop: bool = True,
|
| 1047 |
+
min_radius_frac: float = 0.1,
|
| 1048 |
+
max_radius_frac: float = 0.5,
|
| 1049 |
+
allow_overflow: bool = False,
|
| 1050 |
+
softmax_temperature: float = 0.1,
|
| 1051 |
+
**kwargs,
|
| 1052 |
+
):
|
| 1053 |
+
"""
|
| 1054 |
+
Initialize the EyeCLAHEImageProcessor.
|
| 1055 |
+
|
| 1056 |
+
Args:
|
| 1057 |
+
size: Output image size (square)
|
| 1058 |
+
crop_scale_factor: Scale factor for crop box (relative to detected radius)
|
| 1059 |
+
clahe_grid_size: Number of tiles for CLAHE
|
| 1060 |
+
clahe_clip_limit: Histogram clip limit for CLAHE
|
| 1061 |
+
normalization_mode: 'imagenet', 'none', or 'custom'
|
| 1062 |
+
custom_mean: Custom normalization mean (if mode='custom')
|
| 1063 |
+
custom_std: Custom normalization std (if mode='custom')
|
| 1064 |
+
do_clahe: Whether to apply CLAHE
|
| 1065 |
+
do_crop: Whether to perform eye-centered cropping
|
| 1066 |
+
min_radius_frac: Minimum radius as fraction of image size
|
| 1067 |
+
max_radius_frac: Maximum radius as fraction of image size
|
| 1068 |
+
allow_overflow: If True, allow crop box to extend beyond image bounds
|
| 1069 |
+
and fill missing regions with black. Useful for pre-cropped
|
| 1070 |
+
images where the fundus circle is partially cut off.
|
| 1071 |
+
softmax_temperature: Temperature for soft argmax in eye center detection.
|
| 1072 |
+
Lower values (0.01-0.1) give sharper peak detection, higher values
|
| 1073 |
+
(0.3-0.5) provide more averaging for noisy images. Default: 0.1.
|
| 1074 |
+
"""
|
| 1075 |
+
super().__init__(**kwargs)
|
| 1076 |
+
|
| 1077 |
+
self.size = size
|
| 1078 |
+
self.crop_scale_factor = crop_scale_factor
|
| 1079 |
+
self.clahe_grid_size = clahe_grid_size
|
| 1080 |
+
self.clahe_clip_limit = clahe_clip_limit
|
| 1081 |
+
self.normalization_mode = normalization_mode
|
| 1082 |
+
self.custom_mean = custom_mean
|
| 1083 |
+
self.custom_std = custom_std
|
| 1084 |
+
self.do_clahe = do_clahe
|
| 1085 |
+
self.do_crop = do_crop
|
| 1086 |
+
self.min_radius_frac = min_radius_frac
|
| 1087 |
+
self.max_radius_frac = max_radius_frac
|
| 1088 |
+
self.allow_overflow = allow_overflow
|
| 1089 |
+
self.softmax_temperature = softmax_temperature
|
| 1090 |
+
|
| 1091 |
+
def preprocess(
|
| 1092 |
+
self,
|
| 1093 |
+
images,
|
| 1094 |
+
return_tensors: str = "pt",
|
| 1095 |
+
device: Optional[Union[str, torch.device]] = None,
|
| 1096 |
+
**kwargs,
|
| 1097 |
+
) -> BatchFeature:
|
| 1098 |
+
"""
|
| 1099 |
+
Preprocess images for model input.
|
| 1100 |
+
|
| 1101 |
+
Args:
|
| 1102 |
+
images: Input images in any of these formats:
|
| 1103 |
+
- torch.Tensor: (C,H,W), (B,C,H,W), or list of tensors
|
| 1104 |
+
- PIL.Image.Image: single image or list of images
|
| 1105 |
+
- numpy.ndarray: (H,W,C), (B,H,W,C), or list of arrays
|
| 1106 |
+
return_tensors: Return type (only "pt" supported)
|
| 1107 |
+
device: Target device for processing (e.g., "cuda", "cpu")
|
| 1108 |
+
|
| 1109 |
+
Returns:
|
| 1110 |
+
BatchFeature with 'pixel_values' key containing (B, C, size, size) tensor
|
| 1111 |
+
"""
|
| 1112 |
+
if return_tensors != "pt":
|
| 1113 |
+
raise ValueError("Only 'pt' (PyTorch) tensors are supported")
|
| 1114 |
+
|
| 1115 |
+
# Determine device
|
| 1116 |
+
if device is not None:
|
| 1117 |
+
device = torch.device(device)
|
| 1118 |
+
elif isinstance(images, torch.Tensor):
|
| 1119 |
+
device = images.device
|
| 1120 |
+
elif isinstance(images, list) and len(images) > 0 and isinstance(images[0], torch.Tensor):
|
| 1121 |
+
device = images[0].device
|
| 1122 |
+
else:
|
| 1123 |
+
# PIL images and numpy arrays default to CPU
|
| 1124 |
+
device = torch.device('cpu')
|
| 1125 |
+
|
| 1126 |
+
# Standardize input
|
| 1127 |
+
images = standardize_input(images, device)
|
| 1128 |
+
B, C, H, W = images.shape
|
| 1129 |
+
|
| 1130 |
+
if self.do_crop:
|
| 1131 |
+
# Estimate eye center
|
| 1132 |
+
cx, cy = estimate_eye_center(images, softmax_temperature=self.softmax_temperature)
|
| 1133 |
+
|
| 1134 |
+
# Estimate radius
|
| 1135 |
+
radius = estimate_radius(
|
| 1136 |
+
images, cx, cy,
|
| 1137 |
+
min_radius_frac=self.min_radius_frac,
|
| 1138 |
+
max_radius_frac=self.max_radius_frac,
|
| 1139 |
+
)
|
| 1140 |
+
|
| 1141 |
+
# Compute crop box
|
| 1142 |
+
x1, y1, x2, y2 = compute_crop_box(
|
| 1143 |
+
cx, cy, radius, H, W,
|
| 1144 |
+
scale_factor=self.crop_scale_factor,
|
| 1145 |
+
allow_overflow=self.allow_overflow,
|
| 1146 |
+
)
|
| 1147 |
+
|
| 1148 |
+
# Crop and resize
|
| 1149 |
+
# Use 'zeros' padding when allow_overflow is True to fill out-of-bounds with black
|
| 1150 |
+
padding_mode = 'zeros' if self.allow_overflow else 'border'
|
| 1151 |
+
images = batch_crop_and_resize(images, x1, y1, x2, y2, self.size, padding_mode=padding_mode)
|
| 1152 |
+
else:
|
| 1153 |
+
# Just resize
|
| 1154 |
+
images = resize_images(images, self.size)
|
| 1155 |
+
|
| 1156 |
+
# Apply CLAHE
|
| 1157 |
+
if self.do_clahe:
|
| 1158 |
+
images = apply_clahe_vectorized(
|
| 1159 |
+
images,
|
| 1160 |
+
grid_size=self.clahe_grid_size,
|
| 1161 |
+
clip_limit=self.clahe_clip_limit,
|
| 1162 |
+
)
|
| 1163 |
+
|
| 1164 |
+
# Normalize
|
| 1165 |
+
images = normalize_images(
|
| 1166 |
+
images,
|
| 1167 |
+
mean=self.custom_mean,
|
| 1168 |
+
std=self.custom_std,
|
| 1169 |
+
mode=self.normalization_mode,
|
| 1170 |
+
)
|
| 1171 |
+
|
| 1172 |
+
return BatchFeature(data={"pixel_values": images}, tensor_type="pt")
|
| 1173 |
+
|
| 1174 |
+
def __call__(
|
| 1175 |
+
self,
|
| 1176 |
+
images: Union[torch.Tensor, List[torch.Tensor]],
|
| 1177 |
+
**kwargs,
|
| 1178 |
+
) -> BatchFeature:
|
| 1179 |
+
"""
|
| 1180 |
+
Process images (alias for preprocess).
|
| 1181 |
+
"""
|
| 1182 |
+
return self.preprocess(images, **kwargs)
|
| 1183 |
+
|
| 1184 |
+
|
| 1185 |
+
# For AutoImageProcessor registration
|
| 1186 |
+
EyeGPUImageProcessor = EyeCLAHEImageProcessor
|
preprocessor_config.json
ADDED
|
@@ -0,0 +1,20 @@
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 1 |
+
{
|
| 2 |
+
"image_processor_type": "EyeCLAHEImageProcessor",
|
| 3 |
+
"auto_map": {
|
| 4 |
+
"AutoImageProcessor": "image_processing_eye_gpu.EyeCLAHEImageProcessor"
|
| 5 |
+
},
|
| 6 |
+
"size": 512,
|
| 7 |
+
"crop_scale_factor": 1.1,
|
| 8 |
+
"clahe_grid_size": 8,
|
| 9 |
+
"clahe_clip_limit": 2.0,
|
| 10 |
+
"normalization_mode": "imagenet",
|
| 11 |
+
"custom_mean": null,
|
| 12 |
+
"custom_std": null,
|
| 13 |
+
"do_clahe": true,
|
| 14 |
+
"do_crop": true,
|
| 15 |
+
"min_radius_frac": 0.1,
|
| 16 |
+
"max_radius_frac": 1.2,
|
| 17 |
+
"allow_overflow": true,
|
| 18 |
+
"softmax_temperature": 0.1,
|
| 19 |
+
"processor_class": "EyeCLAHEImageProcessor"
|
| 20 |
+
}
|