File size: 4,877 Bytes
83dd2a8
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
import torch
from transformers import LayoutLMv3Processor, LayoutLMv3ForTokenClassification
from PIL import Image
import numpy as np
from typing import Dict, List, Tuple, Optional
import logging

logger = logging.getLogger(__name__)

class FormIQModel:
    def __init__(
        self,
        model_name: str = "microsoft/layoutlmv3-base",
        device: str = "cuda" if torch.cuda.is_available() else "cpu"
    ):
        """Initialize the FormIQ model with LayoutLMv3.
        
        Args:
            model_name: Name of the pre-trained model to use
            device: Device to run the model on ('cuda' or 'cpu')
        """
        self.device = device
        self.processor = LayoutLMv3Processor.from_pretrained(model_name)
        self.model = LayoutLMv3ForTokenClassification.from_pretrained(model_name)
        self.model.to(device)
        logger.info(f"Model initialized on {device}")

    def preprocess_image(self, image: Image.Image) -> Dict[str, torch.Tensor]:
        """Preprocess the input image for the model.
        
        Args:
            image: PIL Image to process
            
        Returns:
            Dictionary of processed inputs
        """
        try:
            # Process image and text
            encoding = self.processor(
                image,
                return_tensors="pt",
                truncation=True,
                max_length=512
            )
            
            # Move tensors to device
            encoding = {k: v.to(self.device) for k, v in encoding.items()}
            return encoding
            
        except Exception as e:
            logger.error(f"Error preprocessing image: {str(e)}")
            raise

    def predict(
        self,
        image: Image.Image,
        confidence_threshold: float = 0.5
    ) -> Dict[str, List[Dict[str, any]]]:
        """Extract information from the document image.
        
        Args:
            image: PIL Image of the document
            confidence_threshold: Minimum confidence score for predictions
            
        Returns:
            Dictionary containing extracted fields and their metadata
        """
        try:
            # Preprocess image
            inputs = self.preprocess_image(image)
            
            # Get model predictions
            with torch.no_grad():
                outputs = self.model(**inputs)
                predictions = outputs.logits.argmax(-1).squeeze().cpu().numpy()
                scores = torch.softmax(outputs.logits, dim=-1).max(-1)[0].squeeze().cpu().numpy()
            
            # Process predictions
            extracted_fields = self._process_predictions(predictions, scores, confidence_threshold)
            
            return {
                "fields": extracted_fields,
                "metadata": {
                    "confidence_scores": scores.tolist(),
                    "model_version": self.model.config.model_type
                }
            }
            
        except Exception as e:
            logger.error(f"Error during prediction: {str(e)}")
            raise

    def _process_predictions(
        self,
        predictions: np.ndarray,
        scores: np.ndarray,
        confidence_threshold: float
    ) -> List[Dict[str, any]]:
        """Process raw model predictions into structured output.
        
        Args:
            predictions: Array of predicted class indices
            scores: Array of confidence scores
            confidence_threshold: Minimum confidence score
            
        Returns:
            List of dictionaries containing field information
        """
        # TODO: Implement field-specific post-processing
        # This is a placeholder implementation
        processed_fields = []
        
        for pred, score in zip(predictions, scores):
            if score >= confidence_threshold:
                field_info = {
                    "label": self.model.config.id2label[pred],
                    "confidence": float(score),
                    "bbox": None  # TODO: Add bounding box information
                }
                processed_fields.append(field_info)
        
        return processed_fields

    def validate_extraction(
        self,
        extracted_fields: Dict[str, List[Dict[str, any]]],
        document_type: str
    ) -> Dict[str, any]:
        """Validate extracted fields based on document type rules.
        
        Args:
            extracted_fields: Dictionary of extracted fields
            document_type: Type of document (e.g., 'invoice', 'receipt')
            
        Returns:
            Dictionary containing validation results
        """
        # TODO: Implement field validation logic
        # This is a placeholder implementation
        return {
            "is_valid": True,
            "validation_errors": [],
            "confidence_score": 1.0
        }