AI Defect Detection
Overview
This skill implements deep learning-based defect detection for construction quality control. Analyze images and video to automatically identify structural and surface defects, classify severity, and generate inspection reports.
Detectable Defects:
- Concrete: Cracks, spalling, honeycombing, efflorescence
- Steel: Corrosion, weld defects, deformation
- Masonry: Mortar deterioration, displacement
- Finishes: Surface defects, coating failures
- MEP: Insulation damage, pipe corrosion
Quick Start
import torch
import torch.nn as nn
from torchvision import transforms, models
from PIL import Image
from dataclasses import dataclass
from typing import List, Dict, Tuple
from enum import Enum
class DefectType(Enum):
CRACK = "crack"
SPALLING = "spalling"
CORROSION = "corrosion"
HONEYCOMBING = "honeycombing"
EFFLORESCENCE = "efflorescence"
DEFORMATION = "deformation"
SURFACE_DAMAGE = "surface_damage"
NO_DEFECT = "no_defect"
class SeverityLevel(Enum):
MINOR = "minor"
MODERATE = "moderate"
SEVERE = "severe"
CRITICAL = "critical"
@dataclass
class DefectDetection:
defect_type: DefectType
confidence: float
severity: SeverityLevel
bounding_box: Tuple[int, int, int, int] # x1, y1, x2, y2
area_ratio: float # Defect area as ratio of image
# Simple classifier using pretrained model
class SimpleDefectClassifier:
def __init__(self, num_classes: int = 8):
self.model = models.resnet18(pretrained=True)
self.model.fc = nn.Linear(self.model.fc.in_features, num_classes)
self.model.eval()
self.transform = transforms.Compose([
transforms.Resize((224, 224)),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])
])
self.classes = list(DefectType)
def predict(self, image_path: str) -> DefectDetection:
"""Classify defect in image"""
image = Image.open(image_path).convert('RGB')
input_tensor = self.transform(image).unsqueeze(0)
with torch.no_grad():
outputs = self.model(input_tensor)
probs = torch.softmax(outputs, dim=1)
confidence, predicted = torch.max(probs, 1)
defect_type = self.classes[predicted.item()]
return DefectDetection(
defect_type=defect_type,
confidence=confidence.item(),
severity=self._estimate_severity(confidence.item()),
bounding_box=(0, 0, image.width, image.height),
area_ratio=1.0
)
def _estimate_severity(self, confidence: float) -> SeverityLevel:
if confidence > 0.9:
return SeverityLevel.CRITICAL
elif confidence > 0.7:
return SeverityLevel.SEVERE
elif confidence > 0.5:
return SeverityLevel.MODERATE
else:
return SeverityLevel.MINOR
# Usage
classifier = SimpleDefectClassifier()
# result = classifier.predict("concrete_image.jpg")
# print(f"Defect: {result.defect_type.value}, Confidence: {result.confidence:.2%}")
Comprehensive Defect Detection System
Object Detection Model
import torch
import torch.nn as nn
from torchvision import transforms
from torchvision.models.detection import fasterrcnn_resnet50_fpn
from PIL import Image
import numpy as np
from dataclasses import dataclass, field
from typing import List, Dict, Tuple, Optional
from datetime import datetime
import json
@dataclass
class BoundingBox:
x1: int
y1: int
x2: int
y2: int
@property
def width(self) -> int:
return self.x2 - self.x1
@property
def height(self) -> int:
return self.y2 - self.y1
@property
def area(self) -> int:
return self.width * self.height
@property
def center(self) -> Tuple[int, int]:
return ((self.x1 + self.x2) // 2, (self.y1 + self.y2) // 2)
@dataclass
class DetectedDefect:
defect_id: str
defect_type: DefectType
confidence: float
severity: SeverityLevel
bounding_box: BoundingBox
area_sqm: Optional[float] = None
dimensions_mm: Optional[Tuple[float, float]] = None
metadata: Dict = field(default_factory=dict)
@dataclass
class InspectionResult:
inspection_id: str
image_path: str
timestamp: datetime
location: str
element_type: str
defects: List[DetectedDefect]
overall_condition: str
recommended_actions: List[str]
class DefectDetectionModel:
"""Deep learning defect detection with object detection"""
DEFECT_CLASSES = {
1: DefectType.CRACK,
2: DefectType.SPALLING,
3: DefectType.CORROSION,
4: DefectType.HONEYCOMBING,
5: DefectType.EFFLORESCENCE,
6: DefectType.DEFORMATION,
7: DefectType.SURFACE_DAMAGE
}
def __init__(self, model_path: str = None, device: str = 'cpu'):
self.device = torch.device(device)
# Initialize Faster R-CNN
self.model = fasterrcnn_resnet50_fpn(pretrained=True)
# Modify for our classes
num_classes = len(self.DEFECT_CLASSES) + 1 # +1 for background
in_features = self.model.roi_heads.box_predictor.cls_score.in_features
self.model.roi_heads.box_predictor = FastRCNNPredictor(in_features, num_classes)
if model_path:
self.model.load_state_dict(torch.load(model_path, map_location=self.device))
self.model.to(self.device)
self.model.eval()
self.transform = transforms.Compose([
transforms.ToTensor()
])
def detect(self, image_path: str, confidence_threshold: float = 0.5,
pixels_per_mm: float = None) -> List[DetectedDefect]:
"""Detect defects in image"""
image = Image.open(image_path).convert('RGB')
image_tensor = self.transform(image).to(self.device)
with torch.no_grad():
predictions = self.model([image_tensor])
pred = predictions[0]
defects = []
for i in range(len(pred['boxes'])):
score = pred['scores'][i].item()
if score < confidence_threshold:
continue
label = pred['labels'][i].item()
box = pred['boxes'][i].cpu().numpy()
defect_type = self.DEFECT_CLASSES.get(label, DefectType.SURFACE_DAMAGE)
bbox = BoundingBox(
x1=int(box[0]),
y1=int(box[1]),
x2=int(box[2]),
y2=int(box[3])
)
# Calculate dimensions if scale provided
dimensions_mm = None
if pixels_per_mm:
width_mm = bbox.width / pixels_per_mm
height_mm = bbox.height / pixels_per_mm
dimensions_mm = (width_mm, height_mm)
severity = self._classify_severity(defect_type, bbox, image.size)
defects.append(DetectedDefect(
defect_id=f"DEF-{i:04d}",
defect_type=defect_type,
confidence=score,
severity=severity,
bounding_box=bbox,
dimensions_mm=dimensions_mm
))
return defects
def _classify_severity(self, defect_type: DefectType,
bbox: BoundingBox,
image_size: Tuple[int, int]) -> SeverityLevel:
"""Classify defect severity based on type and size"""
image_area = image_size[0] * image_size[1]
defect_ratio = bbox.area / image_area
# Severity thresholds by defect type
thresholds = {
DefectType.CRACK: {'critical': 0.1, 'severe': 0.05, 'moderate': 0.02},
DefectType.SPALLING: {'critical': 0.15, 'severe': 0.08, 'moderate': 0.03},
DefectType.CORROSION: {'critical': 0.2, 'severe': 0.1, 'moderate': 0.05},
DefectType.HONEYCOMBING: {'critical': 0.1, 'severe': 0.05, 'moderate': 0.02},