tasks/image.py

import os
import torch
import numpy as np

from loguru import logger
from tqdm import tqdm
from dotenv import load_dotenv

from fastapi import APIRouter
from datetime import datetime
from datasets import load_dataset
from sklearn.metrics import accuracy_score, precision_score, recall_score

from .utils.evaluation import ImageEvaluationRequest
from .utils.emissions import tracker, clean_emissions_data, get_space_info

from ultralytics import YOLO
from ultralytics import RTDETR
from torch.utils.data import DataLoader
from torchvision import transforms

from dotenv import load_dotenv

load_dotenv()
router = APIRouter()
DESCRIPTION = "Image to detect smoke"
ROUTE = "/image"

device = torch.device("cuda")

    
def parse_boxes(annotation_string):
    """Parse multiple boxes from a single annotation string.
    Each box has 5 values: class_id, x_center, y_center, width, height"""
    values = [float(x) for x in annotation_string.strip().split()]
    boxes = []
    # Each box has 5 values
    for i in range(0, len(values), 5):
        if i + 5 <= len(values):
            # Skip class_id (first value) and take the next 4 values
            box = values[i + 1:i + 5]
            boxes.append(box)
    return boxes


def compute_iou(box1, box2):
    """Compute Intersection over Union (IoU) between two YOLO format boxes."""

    # Convert YOLO format (x_center, y_center, width, height) to corners
    def yolo_to_corners(box):
        x_center, y_center, width, height = box
        x1 = x_center - width / 2
        y1 = y_center - height / 2
        x2 = x_center + width / 2
        y2 = y_center + height / 2
        return np.array([x1, y1, x2, y2])

    box1_corners = yolo_to_corners(box1)
    box2_corners = yolo_to_corners(box2)

    # Calculate intersection
    x1 = max(box1_corners[0], box2_corners[0])
    y1 = max(box1_corners[1], box2_corners[1])
    x2 = min(box1_corners[2], box2_corners[2])
    y2 = min(box1_corners[3], box2_corners[3])

    intersection = max(0, x2 - x1) * max(0, y2 - y1)

    # Calculate union
    box1_area = (box1_corners[2] - box1_corners[0]) * (box1_corners[3] - box1_corners[1])
    box2_area = (box2_corners[2] - box2_corners[0]) * (box2_corners[3] - box2_corners[1])
    union = box1_area + box2_area - intersection

    return intersection / (union + 1e-6)


def compute_max_iou(true_boxes, pred_box):
    """Compute maximum IoU between a predicted box and all true boxes"""
    max_iou = 0
    for true_box in true_boxes:
        iou = compute_iou(true_box, pred_box)
        max_iou = max(max_iou, iou)
    return max_iou


class ClampTransform:
    def __init__(self, min_val=0.0, max_val=1.0):
        self.min_val = min_val
        self.max_val = max_val

    def __call__(self, tensor):
        return torch.clamp(tensor, min=self.min_val, max=self.max_val)


def collate_fn(batch):
    images = [item['image'] for item in batch]
    annotations = [item.get('annotations', '') for item in batch]

    # Convert PIL Images to tensors
    transform = transforms.Compose([
        transforms.ToTensor(),
        ClampTransform(min_val=0.0, max_val=1.0),
        transforms.Resize((640, 640))
    ])

    images = [transform(img) for img in images]
    images = torch.stack(images)
    return {'image': images, 'annotations': annotations}


def parse_boxes(annotation_string):
    """Parse multiple boxes from a single annotation string.
    Each box has 5 values: class_id, x_center, y_center, width, height"""
    values = [float(x) for x in annotation_string.strip().split()]
    boxes = []
    # Each box has 5 values
    for i in range(0, len(values), 5):
        if i + 5 <= len(values):
            # Skip class_id (first value) and take the next 4 values
            box = values[i+1:i+5]
            boxes.append(box)
    return boxes


def compute_iou(box1, box2):
    """Compute Intersection over Union (IoU) between two YOLO format boxes."""
    # Convert YOLO format (x_center, y_center, width, height) to corners
    def yolo_to_corners(box):
        x_center, y_center, width, height = box
        x1 = x_center - width/2
        y1 = y_center - height/2
        x2 = x_center + width/2
        y2 = y_center + height/2
        return np.array([x1, y1, x2, y2])
    
    box1_corners = yolo_to_corners(box1)
    box2_corners = yolo_to_corners(box2)
    
    # Calculate intersection
    x1 = max(box1_corners[0], box2_corners[0])
    y1 = max(box1_corners[1], box2_corners[1])
    x2 = min(box1_corners[2], box2_corners[2])
    y2 = min(box1_corners[3], box2_corners[3])
    
    intersection = max(0, x2 - x1) * max(0, y2 - y1)
    
    # Calculate union
    box1_area = (box1_corners[2] - box1_corners[0]) * (box1_corners[3] - box1_corners[1])
    box2_area = (box2_corners[2] - box2_corners[0]) * (box2_corners[3] - box2_corners[1])
    union = box1_area + box2_area - intersection
    
    return intersection / (union + 1e-6)


def compute_max_iou(true_boxes, pred_box):
    """Compute maximum IoU between a predicted box and all true boxes"""
    max_iou = 0
    for true_box in true_boxes:
        iou = compute_iou(true_box, pred_box)
        max_iou = max(max_iou, iou)
    return max_iou


@router.post(ROUTE, tags=["Image Task"],
              description=DESCRIPTION)
async def evaluate_image(model_path: str = "models/yolo11s_best.pt", request: ImageEvaluationRequest = ImageEvaluationRequest()):
    """
    Evaluate image classification and object detection for forest fire smoke.
    
    Current Model: Random Baseline
    - Makes random predictions for both classification and bounding boxes
    - Used as a baseline for comparison
    
    Metrics:
    - Classification accuracy: Whether an image contains smoke or not
    - Object Detection accuracy: IoU (Intersection over Union) for smoke bounding boxes
    """
    # Get space info
    username, space_url = get_space_info()
    
    # Load and prepare the dataset
    dataset = load_dataset(request.dataset_name, token=os.getenv("HF_TOKEN"))
    
    # Split dataset
    train_test = dataset["train"]
    test_dataset = dataset["val"]
    if("yolo" in model_path):
        model = YOLO(model_path, task="detect")
    if("detr" in model_path):
        model = RTDETR(model_path)
    
    # Start tracking emissions
    tracker.start()
    tracker.start_task("inference")
    
    #--------------------------------------------------------------------------------------------
    # YOUR MODEL INFERENCE CODE HERE
    # Update the code below to replace the random baseline with your model inference
    #--------------------------------------------------------------------------------------------   
    
    predictions = []
    true_labels = []
    pred_boxes = []
    true_boxes_list = []  # List of lists, each inner list contains boxes for one image

    for example in tqdm(test_dataset):
        # Parse true annotation (YOLO format: class_id x_center y_center width height)
        annotation = example.get("annotations", "").strip()
        has_smoke = len(annotation) > 0
        true_labels.append(int(has_smoke))
        
        image=example["image"]
        results = model(image, verbose=False)
        boxes = results[0].boxes.xywh.tolist()

        pred_has_smoke = len(boxes) > 0
        predictions.append(int(pred_has_smoke))

        if has_smoke:
            # If there's a true box, parse it and make box prediction
            # Parse all true boxes from the annotation
            image_true_boxes = parse_boxes(annotation)
    
            # Predicted bboxes
            # Iterate through the results
            for box in boxes:
                x, y, w, h = box
                image_width, image_height = image.size
                x = x / image_width
                y = y / image_height
                w_n = w / image_width
                h_n = h / image_height
                formatted_box = [x, y, w_n, h_n]
                pred_boxes.append(formatted_box)
                true_boxes_list.append(image_true_boxes)
            
    #--------------------------------------------------------------------------------------------
    # YOUR MODEL INFERENCE STOPS HERE
    #--------------------------------------------------------------------------------------------   
    
    # Stop tracking emissions
    emissions_data = tracker.stop_task()
    
    # Calculate classification metrics
    classification_accuracy = accuracy_score(true_labels, predictions)
    classification_precision = precision_score(true_labels, predictions)
    classification_recall = recall_score(true_labels, predictions)
    
    # Calculate mean IoU for object detection (only for images with smoke)
    # For each image, we compute the max IoU between the predicted box and all true boxes
    ious = []
    for true_boxes, pred_box in zip(true_boxes_list, pred_boxes):
        max_iou = compute_max_iou(true_boxes, pred_box)
        ious.append(max_iou)
    
    mean_iou = float(np.mean(ious)) if ious else 0.0
    
    # Prepare results dictionary
    results = {
        "username": username,
        "space_url": space_url,
        "submission_timestamp": datetime.now().isoformat(),
        "model_description": DESCRIPTION,
        "classification_accuracy": float(classification_accuracy),
        "classification_precision": float(classification_precision),
        "classification_recall": float(classification_recall),
        "mean_iou": mean_iou,
        "energy_consumed_wh": emissions_data.energy_consumed * 1000,
        "emissions_gco2eq": emissions_data.emissions * 1000,
        "emissions_data": clean_emissions_data(emissions_data),
        "api_route": ROUTE,
        "dataset_config": {
            "dataset_name": request.dataset_name,
            "test_size": request.test_size,
            "test_seed": request.test_seed
        }
    }
    
    return results