Implement PDF image extraction with OCR in OCR worker
This commit adds comprehensive image extraction and OCR functionality to the OCR worker:
Features:
- Created image-extractor.js worker module with extractImagesFromPage() function
- Uses pdftoppm (with ImageMagick fallback) to convert PDF pages to high-res images
- Images saved to /uploads/{documentId}/images/page-{N}-img-{M}.png
- Returns image metadata: id, path, position, width, height
OCR Worker Integration:
- Imports image-extractor module and extractTextFromImage from OCR service
- After processing page text, extracts images from each page
- Runs Tesseract OCR on extracted images
- Stores image data in document_images table with extracted text and confidence
- Indexes images in Meilisearch with type='image' for searchability
- Updates document.imageCount and sets imagesExtracted flag
Database:
- Uses existing document_images table from migration 004
- Stores image metadata, OCR text, and confidence scores
Dependencies:
- Added pdf-img-convert and sharp packages
- Uses system tools (pdftoppm/ImageMagick) for reliable PDF conversion
Testing:
- Created test-image-extraction.js to verify image extraction
- Created test-full-pipeline.js to test end-to-end extraction + OCR
- Successfully tested with 05-versions-space.pdf test document
Error Handling:
- Graceful degradation if image extraction fails
- Continues OCR processing even if images cannot be extracted
- Comprehensive logging for debugging
Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
This commit is contained in:
ggq-admin
parent
4b91896838
commit
09d9f1b601
5 changed files with 426 additions and 17 deletions
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@ -9,26 +9,33 @@
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"dev": "node --watch index.js",
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"init-db": "node db/init.js"
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},
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"keywords": ["boat", "manuals", "ocr", "meilisearch"],
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"keywords": [
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"boat",
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"manuals",
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"ocr",
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"meilisearch"
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],
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"author": "",
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"license": "MIT",
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"dependencies": {
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"express": "^5.0.0",
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"better-sqlite3": "^11.0.0",
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"meilisearch": "^0.41.0",
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"bullmq": "^5.0.0",
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"ioredis": "^5.0.0",
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"helmet": "^7.0.0",
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"express-rate-limit": "^7.0.0",
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"cors": "^2.8.5",
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"tesseract.js": "^5.0.0",
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"pdf-parse": "^1.1.1",
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"uuid": "^10.0.0",
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"bcrypt": "^5.1.0",
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"jsonwebtoken": "^9.0.0",
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"multer": "^1.4.5-lts.1",
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"better-sqlite3": "^11.0.0",
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"bullmq": "^5.0.0",
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"cors": "^2.8.5",
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"dotenv": "^16.0.0",
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"express": "^5.0.0",
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"express-rate-limit": "^7.0.0",
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"file-type": "^19.0.0",
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"dotenv": "^16.0.0"
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"helmet": "^7.0.0",
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"ioredis": "^5.0.0",
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"jsonwebtoken": "^9.0.0",
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"meilisearch": "^0.41.0",
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"multer": "^1.4.5-lts.1",
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"pdf-img-convert": "^2.0.0",
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"pdf-parse": "^1.1.1",
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"sharp": "^0.34.4",
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"tesseract.js": "^5.0.0",
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"uuid": "^10.0.0"
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},
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"devDependencies": {
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"@types/node": "^20.0.0"
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63
server/test-full-pipeline.js
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63
server/test-full-pipeline.js
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@ -0,0 +1,63 @@
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#!/usr/bin/env node
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/**
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* Test full image extraction and OCR pipeline
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*/
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import { extractImagesFromPage } from './workers/image-extractor.js';
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import { extractTextFromImage } from './services/ocr.js';
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import path from 'path';
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import { fileURLToPath } from 'url';
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const __filename = fileURLToPath(import.meta.url);
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const __dirname = path.dirname(__filename);
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async function testFullPipeline() {
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console.log('=== Testing Full Image Extraction + OCR Pipeline ===\n');
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const testPdfPath = '/home/setup/navidocs/test/data/05-versions-space.pdf';
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const documentId = 'test_doc_' + Date.now();
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console.log(`Test PDF: ${testPdfPath}`);
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console.log(`Document ID: ${documentId}\n`);
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try {
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// Step 1: Extract images from page 1
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console.log('Step 1: Extracting images from page 1...');
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const images = await extractImagesFromPage(testPdfPath, 1, documentId);
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console.log(`✅ Extracted ${images.length} image(s)\n`);
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if (images.length === 0) {
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console.log('No images to process. Test complete.');
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return;
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}
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// Step 2: Run OCR on each extracted image
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console.log('Step 2: Running OCR on extracted images...\n');
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for (const image of images) {
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console.log(`Processing image: ${image.relativePath}`);
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console.log(` Dimensions: ${image.width}x${image.height}`);
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try {
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const ocrResult = await extractTextFromImage(image.path, 'eng');
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console.log(` OCR Confidence: ${ocrResult.confidence.toFixed(2)}`);
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console.log(` Text Length: ${ocrResult.text.length} characters`);
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console.log(` Text Preview (first 200 chars):`);
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console.log(` ${ocrResult.text.substring(0, 200).replace(/\n/g, ' ')}...`);
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console.log();
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} catch (ocrError) {
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console.error(` ❌ OCR Error: ${ocrError.message}\n`);
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}
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}
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console.log('=== Full Pipeline Test Complete ===');
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} catch (error) {
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console.error('❌ Pipeline test failed:', error);
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console.error(error.stack);
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process.exit(1);
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}
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}
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testFullPipeline();
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51
server/test-image-extraction.js
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51
server/test-image-extraction.js
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#!/usr/bin/env node
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/**
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* Test image extraction functionality
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*/
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import { extractImagesFromPage } from './workers/image-extractor.js';
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import path from 'path';
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import { fileURLToPath } from 'url';
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const __filename = fileURLToPath(import.meta.url);
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const __dirname = path.dirname(__filename);
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async function testImageExtraction() {
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console.log('=== Testing Image Extraction ===\n');
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const testPdfPath = '/home/setup/navidocs/test/data/05-versions-space.pdf';
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const documentId = 'test_doc_' + Date.now();
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console.log(`Test PDF: ${testPdfPath}`);
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console.log(`Document ID: ${documentId}\n`);
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try {
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// Test extracting from page 1
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console.log('Extracting images from page 1...');
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const images = await extractImagesFromPage(testPdfPath, 1, documentId);
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console.log(`\n✅ Extraction complete!`);
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console.log(`Found ${images.length} image(s)\n`);
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if (images.length > 0) {
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console.log('Image details:');
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images.forEach((img, idx) => {
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console.log(`\n Image ${idx + 1}:`);
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console.log(` ID: ${img.id}`);
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console.log(` Path: ${img.path}`);
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console.log(` Relative Path: ${img.relativePath}`);
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console.log(` Dimensions: ${img.width}x${img.height}`);
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console.log(` Format: ${img.format}`);
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console.log(` Position:`, JSON.stringify(img.position));
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});
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}
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console.log('\n=== Test Complete ===');
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} catch (error) {
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console.error('❌ Test failed:', error);
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console.error(error.stack);
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process.exit(1);
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}
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}
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testImageExtraction();
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179
server/workers/image-extractor.js
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179
server/workers/image-extractor.js
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/**
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* Image Extractor - Extract images from PDF pages and save them
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*
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* Features:
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* - Extract images from specific PDF pages using pdftoppm
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* - Convert images to PNG format using sharp
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* - Save images to organized directory structure
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* - Return image metadata (path, position, dimensions)
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* - Handle errors gracefully
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*/
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import sharp from 'sharp';
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import { promises as fs } from 'fs';
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import { join, dirname } from 'path';
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import { fileURLToPath } from 'url';
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import { execSync } from 'child_process';
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import { existsSync, unlinkSync } from 'fs';
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import { tmpdir } from 'os';
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const __dirname = dirname(fileURLToPath(import.meta.url));
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/**
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* Extract images from a specific PDF page
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*
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* @param {string} pdfPath - Path to the PDF file
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* @param {number} pageNumber - Page number (1-based)
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* @param {string} documentId - Document ID for organizing output
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* @returns {Promise<Array<Object>>} - Array of extracted image objects
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*/
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export async function extractImagesFromPage(pdfPath, pageNumber, documentId) {
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try {
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console.log(`[Image Extractor] Extracting images from page ${pageNumber} of ${pdfPath}`);
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// Create output directory for images
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const uploadsDir = join(__dirname, '../../uploads');
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const documentImagesDir = join(uploadsDir, documentId, 'images');
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// Ensure directory exists
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await fs.mkdir(documentImagesDir, { recursive: true });
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// Create temporary directory for conversion
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const tempDir = join(tmpdir(), 'navidocs-image-extract');
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await fs.mkdir(tempDir, { recursive: true });
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// Use pdftoppm to convert the PDF page to an image
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const tempOutputPrefix = join(tempDir, `page-${Date.now()}-${pageNumber}`);
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const tempImagePath = `${tempOutputPrefix}.png`;
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try {
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// Convert PDF page to PNG using pdftoppm
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execSync(
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`pdftoppm -f ${pageNumber} -l ${pageNumber} -png -singlefile -r 300 "${pdfPath}" "${tempOutputPrefix}"`,
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{ stdio: 'pipe' }
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);
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console.log(`[Image Extractor] Converted page ${pageNumber} to image using pdftoppm`);
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} catch (convertError) {
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console.warn(`[Image Extractor] pdftoppm failed, trying ImageMagick:`, convertError.message);
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// Fallback to ImageMagick
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try {
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execSync(
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`convert -density 300 "${pdfPath}[${pageNumber - 1}]" -quality 90 "${tempImagePath}"`,
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{ stdio: 'pipe' }
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);
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console.log(`[Image Extractor] Converted page ${pageNumber} to image using ImageMagick`);
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} catch (imageMagickError) {
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console.error(`[Image Extractor] Both pdftoppm and ImageMagick failed`);
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return [];
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}
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}
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// Check if the image was created
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if (!existsSync(tempImagePath)) {
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console.log(`[Image Extractor] No image generated for page ${pageNumber}`);
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return [];
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}
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const extractedImages = [];
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try {
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// Process with sharp to get metadata and optimize
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const image = sharp(tempImagePath);
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const metadata = await image.metadata();
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// Generate unique image ID
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const imageId = `img_${documentId}_p${pageNumber}_0`;
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// Save as PNG in the document's images directory
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const imagePath = join(documentImagesDir, `page-${pageNumber}-img-0.png`);
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// Optimize and save the image
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await image
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.png({ compressionLevel: 6 })
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.toFile(imagePath);
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console.log(`[Image Extractor] Saved image: ${imagePath} (${metadata.width}x${metadata.height})`);
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// Build image object
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const imageObj = {
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id: imageId,
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path: imagePath,
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relativePath: `/uploads/${documentId}/images/page-${pageNumber}-img-0.png`,
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position: {
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x: 0,
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y: 0,
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width: metadata.width,
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height: metadata.height
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},
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width: metadata.width,
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height: metadata.height,
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format: 'png',
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pageNumber: pageNumber,
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imageIndex: 0
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};
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extractedImages.push(imageObj);
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// Clean up temporary file
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try {
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unlinkSync(tempImagePath);
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} catch (e) {
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// Ignore cleanup errors
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}
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} catch (imgError) {
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console.error(`[Image Extractor] Error processing image on page ${pageNumber}:`, imgError.message);
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}
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console.log(`[Image Extractor] Extracted ${extractedImages.length} image(s) from page ${pageNumber}`);
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return extractedImages;
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} catch (error) {
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console.error(`[Image Extractor] Error extracting images from page ${pageNumber}:`, error);
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// Return empty array instead of throwing to allow OCR to continue
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return [];
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}
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}
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/**
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* Extract images from all pages of a PDF
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*
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* @param {string} pdfPath - Path to the PDF file
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* @param {string} documentId - Document ID for organizing output
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* @param {number} totalPages - Total number of pages in the PDF
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* @returns {Promise<Array<Object>>} - Array of all extracted image objects
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*/
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export async function extractAllImages(pdfPath, documentId, totalPages) {
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const allImages = [];
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for (let pageNum = 1; pageNum <= totalPages; pageNum++) {
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const pageImages = await extractImagesFromPage(pdfPath, pageNum, documentId);
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allImages.push(...pageImages);
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}
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console.log(`[Image Extractor] Extracted total of ${allImages.length} images from ${totalPages} pages`);
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return allImages;
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}
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/**
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* Clean up extracted images for a document
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*
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* @param {string} documentId - Document ID
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* @returns {Promise<void>}
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*/
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export async function cleanupImages(documentId) {
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try {
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const uploadsDir = join(__dirname, '../../uploads');
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const documentImagesDir = join(uploadsDir, documentId, 'images');
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await fs.rm(documentImagesDir, { recursive: true, force: true });
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console.log(`[Image Extractor] Cleaned up images for document ${documentId}`);
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} catch (error) {
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console.error(`[Image Extractor] Error cleaning up images:`, error.message);
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}
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}
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@ -18,8 +18,9 @@ import { v4 as uuidv4 } from 'uuid';
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import { dirname, join } from 'path';
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import { fileURLToPath } from 'url';
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import { getDb } from '../config/db.js';
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import { extractTextFromPDF, cleanOCRText } from '../services/ocr.js';
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import { extractTextFromPDF, cleanOCRText, extractTextFromImage } from '../services/ocr.js';
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import { indexDocumentPage } from '../services/search.js';
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import { extractImagesFromPage } from './image-extractor.js';
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const __dirname = dirname(fileURLToPath(import.meta.url));
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@ -179,16 +180,124 @@ async function processOCRJob(job) {
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// Continue processing other pages even if indexing fails
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}
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}
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// Extract and process images from this page
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try {
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console.log(`[OCR Worker] Extracting images from page ${pageNumber}`);
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const extractedImages = await extractImagesFromPage(filePath, pageNumber, documentId);
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console.log(`[OCR Worker] Found ${extractedImages.length} image(s) on page ${pageNumber}`);
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// Process each extracted image
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for (const image of extractedImages) {
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try {
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console.log(`[OCR Worker] Running OCR on image: ${image.relativePath}`);
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// Run Tesseract OCR on the extracted image
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const imageOCR = await extractTextFromImage(image.path, document.language || 'eng');
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const imageText = imageOCR.text ? cleanOCRText(imageOCR.text) : '';
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const imageConfidence = imageOCR.confidence || 0;
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console.log(`[OCR Worker] Image OCR complete (confidence: ${imageConfidence.toFixed(2)}, text length: ${imageText.length})`);
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// Generate unique image ID for database
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const imageDbId = `${image.id}_${Date.now()}`;
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// Store image in document_images table
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db.prepare(`
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INSERT INTO document_images (
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id, documentId, pageNumber, imageIndex,
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imagePath, imageFormat, width, height,
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position, extractedText, textConfidence,
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createdAt
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) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
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`).run(
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imageDbId,
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documentId,
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pageNumber,
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image.imageIndex,
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image.relativePath,
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image.format,
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image.width,
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image.height,
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JSON.stringify(image.position),
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imageText,
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imageConfidence,
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now
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);
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console.log(`[OCR Worker] Stored image metadata in database: ${imageDbId}`);
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// Index image in Meilisearch with type='image'
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if (imageText && imageText.length > 0) {
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try {
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// Build a search document for the image
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const imageSearchDoc = {
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id: `image_${documentId}_p${pageNumber}_i${image.imageIndex}`,
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vertical: 'boating', // Default, will be enriched by indexDocumentPage
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organizationId: document.organization_id,
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organizationName: 'Unknown Organization',
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entityId: document.entity_id || 'unknown',
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entityName: 'Unknown Entity',
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entityType: document.entity_type || 'unknown',
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docId: documentId,
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userId: document.uploaded_by,
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documentType: 'image', // Mark as image type
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title: `Image from page ${pageNumber}`,
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pageNumber: pageNumber,
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text: imageText,
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language: document.language || 'en',
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ocrConfidence: imageConfidence,
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createdAt: document.created_at,
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updatedAt: now,
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// Image-specific metadata
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imagePath: image.relativePath,
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imageWidth: image.width,
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imageHeight: image.height
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};
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// Get Meilisearch index and add document
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const { getMeilisearchIndex } = await import('../config/meilisearch.js');
|
||||
const index = await getMeilisearchIndex();
|
||||
await index.addDocuments([imageSearchDoc]);
|
||||
|
||||
console.log(`[OCR Worker] Indexed image in Meilisearch: ${imageSearchDoc.id}`);
|
||||
} catch (imageIndexError) {
|
||||
console.error(`[OCR Worker] Failed to index image in Meilisearch:`, imageIndexError.message);
|
||||
// Continue processing
|
||||
}
|
||||
}
|
||||
} catch (imageOCRError) {
|
||||
console.error(`[OCR Worker] Error processing image ${image.imageIndex} on page ${pageNumber}:`, imageOCRError.message);
|
||||
// Continue with next image
|
||||
}
|
||||
}
|
||||
|
||||
// Update document image count
|
||||
if (extractedImages.length > 0) {
|
||||
db.prepare(`
|
||||
UPDATE documents
|
||||
SET imageCount = COALESCE(imageCount, 0) + ?
|
||||
WHERE id = ?
|
||||
`).run(extractedImages.length, documentId);
|
||||
}
|
||||
} catch (imageExtractionError) {
|
||||
console.error(`[OCR Worker] Error extracting images from page ${pageNumber}:`, imageExtractionError.message);
|
||||
// Continue processing other pages
|
||||
}
|
||||
} catch (pageError) {
|
||||
console.error(`[OCR Worker] Error processing page ${pageNumber}:`, pageError.message);
|
||||
// Continue processing other pages
|
||||
}
|
||||
}
|
||||
|
||||
// Update document status to indexed
|
||||
// Update document status to indexed and mark images as extracted
|
||||
db.prepare(`
|
||||
UPDATE documents
|
||||
SET status = 'indexed',
|
||||
imagesExtracted = 1,
|
||||
updated_at = ?
|
||||
WHERE id = ?
|
||||
`).run(now, documentId);
|
||||
|
|
|
|||
Loading…
Add table
Reference in a new issue