Nomad changes

2026-06-01 23:40:55 +02:00
parent 72b1a0a6ed
commit b4c07d3693
5723 changed files with 1130655 additions and 0 deletions
--- a/docs/snippets/php/utils/image_preprocessing.php
+++ b/docs/snippets/php/utils/image_preprocessing.php
@@ -0,0 +1,187 @@
+```php title="image_preprocessing.php"
+<?php
+
+declare(strict_types=1);
+
+/**
+ * Image Preprocessing for OCR
+ *
+ * Configure image preprocessing settings to improve OCR accuracy on scanned documents.
+ * Demonstrates various preprocessing techniques like denoising, deskewing, and contrast enhancement.
+ */
+
+require_once __DIR__ . '/vendor/autoload.php';
+
+use Kreuzberg\Kreuzberg;
+use Kreuzberg\Config\ExtractionConfig;
+use Kreuzberg\Config\OcrConfig;
+use Kreuzberg\Config\TesseractConfig;
+use Kreuzberg\Config\ImagePreprocessingConfig;
+
+$config = new ExtractionConfig(
+    ocr: new OcrConfig(
+        tesseractConfig: new TesseractConfig(
+            preprocessing: new ImagePreprocessingConfig(
+                targetDpi: 300,
+                denoise: true,
+                deskew: true,
+                contrastEnhance: true,
+                binarizationMethod: 'otsu'
+            )
+        )
+    )
+);
+
+$kreuzberg = new Kreuzberg($config);
+$result = $kreuzberg->extractFile('scanned.pdf');
+
+echo "OCR with Image Preprocessing:\n";
+echo str_repeat('=', 60) . "\n";
+echo "Content extracted: " . strlen($result->content) . " characters\n";
+echo "Preview: " . substr($result->content, 0, 100) . "...\n\n";
+
+$advancedConfig = new ExtractionConfig(
+    ocr: new OcrConfig(
+        backend: 'tesseract',
+        language: 'eng',
+        tesseractConfig: new TesseractConfig(
+            preprocessing: new ImagePreprocessingConfig(
+                targetDpi: 600,          
+                denoise: true,           
+                deskew: true,            
+                contrastEnhance: true,   
+                binarizationMethod: 'adaptive', 
+                sharpen: true,           
+                removeBackground: true   
+            ),
+            pageSegmentationMode: 3,
+            engineMode: 3
+        )
+    )
+);
+
+$kreuzberg = new Kreuzberg($advancedConfig);
+$result = $kreuzberg->extractFile('poor_quality_scan.pdf');
+
+echo "Advanced Preprocessing Results:\n";
+echo str_repeat('=', 60) . "\n";
+echo "Content length: " . strlen($result->content) . " characters\n";
+
+if (isset($result->metadata)) {
+    $qualityScore = $result->qualityScore ?? null;
+    $confidence = $result->metadata['ocr_confidence'] ?? null;
+
+    if ($qualityScore !== null) {
+        echo "Quality score: " . number_format($qualityScore, 2) . "\n";
+
+        if ($qualityScore < 0.5) {
+            echo "Warning: Low quality extraction detected\n";
+            echo "Recommendations:\n";
+            echo "  - Increase target DPI (current: 600)\n";
+            echo "  - Try different binarization method\n";
+            echo "  - Consider rescanning the original document\n";
+        }
+    }
+
+    if ($confidence !== null) {
+        echo "OCR confidence: " . number_format($confidence * 100, 1) . "%\n";
+    }
+}
+
+echo "\n";
+
+$preprocessingProfiles = [
+    'basic' => new ImagePreprocessingConfig(
+        targetDpi: 300,
+        denoise: false,
+        deskew: false,
+        contrastEnhance: false
+    ),
+    'balanced' => new ImagePreprocessingConfig(
+        targetDpi: 300,
+        denoise: true,
+        deskew: true,
+        contrastEnhance: true,
+        binarizationMethod: 'otsu'
+    ),
+    'aggressive' => new ImagePreprocessingConfig(
+        targetDpi: 600,
+        denoise: true,
+        deskew: true,
+        contrastEnhance: true,
+        binarizationMethod: 'adaptive',
+        sharpen: true,
+        removeBackground: true
+    ),
+];
+
+echo "Preprocessing Profile Comparison:\n";
+echo str_repeat('=', 60) . "\n";
+
+foreach ($preprocessingProfiles as $profileName => $preprocessing) {
+    $profileConfig = new ExtractionConfig(
+        ocr: new OcrConfig(
+            tesseractConfig: new TesseractConfig(
+                preprocessing: $preprocessing
+            )
+        )
+    );
+
+    $kreuzberg = new Kreuzberg($profileConfig);
+
+    $startTime = microtime(true);
+    $result = $kreuzberg->extractFile('sample_scan.pdf');
+    $elapsedTime = microtime(true) - $startTime;
+
+    echo ucfirst($profileName) . " profile:\n";
+    echo "  Content length: " . strlen($result->content) . " characters\n";
+    echo "  Processing time: " . number_format($elapsedTime, 3) . " seconds\n";
+    echo "  Settings:\n";
+    echo "    - DPI: {$preprocessing->targetDpi}\n";
+    echo "    - Denoise: " . ($preprocessing->denoise ? 'Yes' : 'No') . "\n";
+    echo "    - Deskew: " . ($preprocessing->deskew ? 'Yes' : 'No') . "\n";
+    echo "    - Binarization: " . ($preprocessing->binarizationMethod ?? 'None') . "\n";
+    echo "\n";
+}
+
+function recommendPreprocessingSettings(string $documentType): ImagePreprocessingConfig
+{
+    return match ($documentType) {
+        'modern_scan' => new ImagePreprocessingConfig(
+            targetDpi: 300,
+            denoise: true,
+            deskew: true,
+            contrastEnhance: false,
+            binarizationMethod: 'otsu'
+        ),
+        'old_document' => new ImagePreprocessingConfig(
+            targetDpi: 600,
+            denoise: true,
+            deskew: true,
+            contrastEnhance: true,
+            binarizationMethod: 'adaptive',
+            removeBackground: true
+        ),
+        'newspaper' => new ImagePreprocessingConfig(
+            targetDpi: 400,
+            denoise: true,
+            deskew: true,
+            contrastEnhance: true,
+            binarizationMethod: 'sauvola',
+            removeBackground: true
+        ),
+        default => new ImagePreprocessingConfig(
+            targetDpi: 300,
+            denoise: true,
+            deskew: true,
+            contrastEnhance: true,
+            binarizationMethod: 'otsu'
+        ),
+    };
+}
+
+echo "Recommended preprocessing for old documents:\n";
+$recommended = recommendPreprocessingSettings('old_document');
+echo "  Target DPI: {$recommended->targetDpi}\n";
+echo "  Binarization: {$recommended->binarizationMethod}\n";
+```