File size: 9,167 Bytes
64deb3c
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
"""
OCR Service - Document Text Extraction via OpenRouter Vision Models
Handles OCR for images and scanned documents using vision-capable models with fallback
"""

import requests
import base64
from pathlib import Path
from config import Config


class OCRService:
    def __init__(self):
        self.api_key = Config.OPENROUTER_API_KEY
        self.base_url = Config.OPENROUTER_BASE_URL
        
        # Vision-capable models for OCR with fallback order
        # Only models that support image/vision input can be used for OCR
        self.ocr_models = [
            "google/gemma-3-27b-it:free",      # Primary - Largest Gemma 3
            "google/gemma-3-12b-it:free",      # Fallback 1
            "google/gemma-3-4b-it:free",       # Fallback 2
            "google/gemma-3n-e4b-it:free",     # Fallback 3
            "google/gemma-3n-e2b-it:free",     # Fallback 4 - Smallest
        ]
    
    def _encode_image(self, image_path: str) -> str:
        """Encode image to base64"""
        with open(image_path, "rb") as f:
            return base64.b64encode(f.read()).decode('utf-8')
    
    def _get_mime_type(self, file_path: str) -> str:
        """Get MIME type from file extension"""
        ext = Path(file_path).suffix.lower()
        mime_types = {
            '.png': 'image/png',
            '.jpg': 'image/jpeg',
            '.jpeg': 'image/jpeg',
            '.gif': 'image/gif',
            '.webp': 'image/webp',
            '.pdf': 'application/pdf'
        }
        return mime_types.get(ext, 'image/png')
    
    def _call_ocr_model(self, image_data: str, mime_type: str, model: str = None) -> dict:
        """Call OpenRouter vision model for OCR"""
        if not self.api_key:
            return {"success": False, "error": "OpenRouter API key not configured"}
        
        headers = {
            "Authorization": f"Bearer {self.api_key}",
            "Content-Type": "application/json",
            "HTTP-Referer": "https://notebooklm-fast.hf.space",
            "X-Title": "NotebookLM Fast OCR"
        }
        
        # OCR prompt for thorough text extraction
        ocr_prompt = """You are a precise OCR system. Extract EVERY SINGLE piece of text from this image/document with 100% accuracy.

CRITICAL INSTRUCTIONS:
1. Extract ALL text - do not skip or miss ANY section, heading, paragraph, or text block
2. Include ALL sections (e.g., Education, Experience, Skills, Contact, Summary, Projects, etc.)
3. Preserve the exact structure and hierarchy of the document
4. Include all names, dates, numbers, addresses, phone numbers, emails, URLs
5. Include text from headers, footers, sidebars, and any text boxes
6. For tables, use markdown table format with all rows and columns
7. For bullet points and lists, preserve the list structure
8. Include any small text, footnotes, or captions

OUTPUT FORMAT:
- Return ONLY the extracted text, explanations
- Maintain the original reading order (top to bottom, left to right)
- Use markdown formatting for structure (headers, lists, tables)
- Separate sections clearly with line breaks

IMPORTANT: Do not summarize or paraphrase. Extract the EXACT text as it appears."""
        
        payload = {
            "model": model or self.ocr_models[0],
            "messages": [
                {
                    "role": "user",
                    "content": [
                        {
                            "type": "image_url",
                            "image_url": {
                                "url": f"data:{mime_type};base64,{image_data}"
                            }
                        },
                        {
                            "type": "text",
                            "text": ocr_prompt
                        }
                    ]
                }
            ],
            "max_tokens": 4096,
            "temperature": 0.1  # Low temperature for accurate extraction
        }
        
        try:
            response = requests.post(
                f"{self.base_url}/chat/completions",
                headers=headers,
                json=payload,
                timeout=120  # Longer timeout for OCR
            )
            
            if response.status_code == 200:
                data = response.json()
                text = data.get('choices', [{}])[0].get('message', {}).get('content', '')
                
                if text:
                    return {"success": True, "text": text, "model": model or self.ocr_models[0]}
                else:
                    return {"success": False, "error": "No text extracted from response"}
            else:
                return {
                    "success": False, 
                    "error": f"OpenRouter API error: {response.status_code} - {response.text}"
                }
        except requests.exceptions.Timeout:
            return {"success": False, "error": "Request timed out. Please try again."}
        except Exception as e:
            return {"success": False, "error": str(e)}
    
    def _call_ocr_with_fallback(self, image_data: str, mime_type: str) -> dict:
        """Try OCR with fallback models"""
        last_error = None
        
        for model in self.ocr_models:
            print(f"Attempting OCR with {model}...")
            result = self._call_ocr_model(image_data, mime_type, model)
            
            if result['success']:
                print(f"OCR successful with {model}")
                return result
            else:
                last_error = result.get('error', 'Unknown error')
                print(f"OCR failed with {model}: {last_error}")
                continue
        
        return {"success": False, "error": f"All OCR models failed. Last error: {last_error}"}
    
    def extract_text_from_pdf(self, pdf_path: str) -> dict:
        """
        Extract text from entire PDF using OpenRouter vision models.
        Converts PDF pages to images and processes them.
        """
        import fitz  # PyMuPDF
        import os
        
        try:
            doc = fitz.open(pdf_path)
            total_pages = len(doc)
            
            print(f"Processing {total_pages} page PDF with OpenRouter vision OCR...")
            
            all_text = []
            
            for page_num in range(total_pages):
                print(f"Processing page {page_num + 1}/{total_pages}...")
                
                page = doc.load_page(page_num)
                
                # Render page to image at good resolution for OCR
                mat = fitz.Matrix(2, 2)  # 2x zoom for better quality
                pix = page.get_pixmap(matrix=mat)
                img_data = pix.tobytes("png")
                
                # Encode to base64
                image_base64 = base64.b64encode(img_data).decode('utf-8')
                
                # OCR the page with fallback
                result = self._call_ocr_with_fallback(image_base64, 'image/png')
                
                if result['success']:
                    all_text.append(f"--- Page {page_num + 1} ---\n{result['text']}")
                else:
                    all_text.append(f"--- Page {page_num + 1} ---\n[Error extracting text: {result['error']}]")
            
            doc.close()
            
            combined_text = "\n\n".join(all_text)
            
            return {
                "success": True, 
                "text": combined_text, 
                "model": "OpenRouter Vision OCR"
            }
            
        except Exception as e:
            return {"success": False, "error": f"Error processing PDF: {str(e)}"}

    def _process_pdf_in_batches(self, pdf_path: str, total_pages: int) -> dict:
        """Split PDF into chunks and process sequentially - kept for compatibility"""
        return self.extract_text_from_pdf(pdf_path)

    def _send_pdf_to_api(self, pdf_path: str) -> dict:
        """Process PDF by converting to images - OpenRouter doesn't have native PDF support"""
        return self.extract_text_from_pdf(pdf_path)
    
    def extract_text(self, image_path: str) -> dict:
        """
        Extract text from image using OpenRouter vision models with fallback
        """
        image_data = self._encode_image(image_path)
        mime_type = self._get_mime_type(image_path)
        
        print(f"Attempting OCR with OpenRouter vision models...")
        result = self._call_ocr_with_fallback(image_data, mime_type)
        
        if result['success']:
            print(f"OCR successful with {result.get('model', 'OpenRouter')}")
        else:
            print(f"OCR failed: {result['error']}")
        
        return result
    
    def extract_text_from_pdf_page(self, page_image_data: bytes, 
                                    page_num: int) -> dict:
        """Extract text from a PDF page image"""
        image_data = base64.b64encode(page_image_data).decode('utf-8')
        
        print(f"Extracting text from PDF page {page_num} with OpenRouter vision OCR...")
        result = self._call_ocr_with_fallback(image_data, 'image/png')
        return result


# Singleton instance
ocr_service = OCRService()