RED-7669: optimize OCR-module performance

* binarize images after reading

ocr-service-v1/ocr-service-processor/src/main/java/com/knecon/fforesight/service/ocr/processor/model/ExtractedImage.java

@@ -0,0 +1,27 @@
+package com.knecon.fforesight.service.ocr.processor.model;
+
+import java.awt.image.BufferedImage;
+
+import org.apache.pdfbox.pdmodel.graphics.color.PDColorSpace;
+import org.apache.pdfbox.util.Matrix;
+
+import lombok.AccessLevel;
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+import lombok.experimental.FieldDefaults;
+
+@Getter
+@RequiredArgsConstructor
+@FieldDefaults(makeFinal = true, level = AccessLevel.PRIVATE)
+public class ExtractedImage {
+
+    int pageNumber;
+    QuadPoint position;
+    int height;
+    int width;
+    BufferedImage image;
+    Matrix ctm;
+    int numberOnPage;
+    PDColorSpace colorSpace;
+
+}

ocr-service-v1/ocr-service-processor/src/main/java/com/knecon/fforesight/service/ocr/processor/model/ExtractedOcrImage.java

@@ -11,6 +11,8 @@ import org.apache.pdfbox.util.Matrix;
 import com.knecon.fforesight.service.ocr.processor.service.threads.OCRThread;
 import com.knecon.fforesight.service.ocr.processor.utils.ImageProcessingUtils;
 import com.pdftron.sdf.Obj;
+import com.sun.jna.StringArray;
+import com.sun.jna.ptr.PointerByReference;
 
 import lombok.AccessLevel;
 import lombok.Getter;
@@ -56,6 +58,19 @@ public class ExtractedOcrImage implements OcrImage {
     }
 
 
+    public ExtractedOcrImage(ExtractedImage image, int targetDpi) {
+        this.pageNumber = image.getPageNumber();
+        this.numberOnPage = image.getNumberOnPage();
+        this.ctm = image.getCtm();
+        this.originalHeight = image.getImage().getHeight();
+        this.originalWidth = image.getImage().getWidth();
+        float imageDPI = Math.abs(image.getImage().getWidth() / (ctm.getScalingFactorX() / 72));
+        this.pix = binarize(image.getImage(), imageDPI, targetDpi);
+        this.height = pix.h;
+        this.width = pix.w;
+    }
+
+
     @SneakyThrows
     private Pix binarize(BufferedImage image, float imageDpi, int targetDpi) {
 

ocr-service-v1/ocr-service-processor/src/main/java/com/knecon/fforesight/service/ocr/processor/model/OcrImage.java

@@ -2,10 +2,12 @@ package com.knecon.fforesight.service.ocr.processor.model;
 
 import java.awt.geom.AffineTransform;
 import java.awt.geom.Point2D;
+import java.awt.image.BufferedImage;
 
 import com.knecon.fforesight.service.ocr.processor.service.threads.OCRThread;
 import com.knecon.fforesight.service.ocr.processor.utils.PdfDpiCalculator;
 
+import lombok.SneakyThrows;
 import net.sourceforge.lept4j.Leptonica1;
 import net.sourceforge.lept4j.Pix;
 import net.sourceforge.lept4j.util.LeptUtils;
@@ -62,6 +64,20 @@ public interface OcrImage {
     }
 
 
+    @SneakyThrows
+    default BufferedImage getBufferedImage() {
+
+        return LeptUtils.convertPixToImage(getPix());
+    }
+
+
+    @SneakyThrows
+    default BufferedImage getRotatedBufferedImage() {
+
+        return LeptUtils.convertPixToImage(getRotatedPix());
+    }
+
+
     /**
      * Retrieves the rotation degree of the OCR image.
      *

ocr-service-v1/ocr-service-processor/src/main/java/com/knecon/fforesight/service/ocr/processor/model/QuadPoint.java

@@ -97,4 +97,10 @@ public record QuadPoint(Point2D a, Point2D b, Point2D c, Point2D d) {
                 d().getY());
     }
 
+
+    public double size() {
+
+        return a().distance(b()) * a().distance(d());
+    }
+
 }

ocr-service-v1/ocr-service-processor/src/main/java/com/knecon/fforesight/service/ocr/processor/service/ImageStreamEngine.java

@@ -24,6 +24,7 @@ import org.apache.pdfbox.pdmodel.graphics.form.PDFormXObject;
 import org.apache.pdfbox.pdmodel.graphics.image.PDImageXObject;
 import org.apache.pdfbox.util.Matrix;
 
+import com.knecon.fforesight.service.ocr.processor.model.ExtractedImage;
 import com.knecon.fforesight.service.ocr.processor.model.ExtractedOcrImage;
 import com.knecon.fforesight.service.ocr.processor.settings.OcrServiceSettings;
 
@@ -34,7 +35,7 @@ import lombok.SneakyThrows;
 public class ImageStreamEngine extends PDFStreamEngine {
 
     private ExtractedOcrImage currentImageOnPage;
-    private List<ExtractedOcrImage> imagesOnCurrentPage;
+    private List<ExtractedImage> imagesOnCurrentPage;
     private OcrServiceSettings settings;
     private int pageNum;
 
@@ -69,21 +70,14 @@ public class ImageStreamEngine extends PDFStreamEngine {
                 }
 
                 Matrix imageCTM = getGraphicsState().getCurrentTransformationMatrix();
-                if (imageXObject.getColorSpace() instanceof PDDeviceRGB) {
+                this.imagesOnCurrentPage.add(new ExtractedImage(pageNum,
-                    BufferedImage image = imageXObject.getImage();
+                        imageXObject.getHeight(),
-                    this.currentImageOnPage = new ExtractedOcrImage(pageNum, imagesOnCurrentPage.size(), image, imageCTM, settings.getDpi());
+                        imageXObject.getWidth(),
-                } else if (imageXObject.getColorSpace() instanceof PDDeviceGray) {
+                        imageXObject.getImage(),
-                    BufferedImage image = imageXObject.getImage();
+                        imageCTM,
-                    this.currentImageOnPage = new ExtractedOcrImage(pageNum, imagesOnCurrentPage.size(), image, imageCTM, settings.getDpi());
+                        imagesOnCurrentPage.size(),
-                } else {
+                        imageXObject.getColorSpace()));
-                    BufferedImage pdfImage = imageXObject.getImage();
+
-                    BufferedImage image = new BufferedImage(pdfImage.getWidth(), pdfImage.getHeight(), BufferedImage.TYPE_BYTE_GRAY);
-                    Graphics g = image.getGraphics();
-                    g.drawImage(pdfImage, 0, 0, null);
-                    g.dispose();
-                    this.currentImageOnPage = new ExtractedOcrImage(pageNum, imagesOnCurrentPage.size(), image, imageCTM, settings.getDpi());
-                }
-                this.imagesOnCurrentPage.add(this.currentImageOnPage);
                 //imagesOnPages.add(this.currentImageOnPage);
             } else if (xobject instanceof PDFormXObject) {
                 PDFormXObject form = (PDFormXObject) xobject;

ocr-service-v1/ocr-service-processor/src/main/java/com/knecon/fforesight/service/ocr/processor/service/OCRService.java

@@ -107,7 +107,7 @@ public class OCRService {
             int numberOfOcrThreads = Math.min(settings.getOcrThreadCount(), document.getNumberOfPages());
             stats = new Statistics(numberOfExtractThreads, numberOfOcrThreads);
 
-            BlockingQueue<OcrImage> ocrImageQueue = new ArrayBlockingQueue<>(numberOfOcrThreads);
+            BlockingQueue<OcrImage> ocrImageQueue = new ArrayBlockingQueue<>(2 * numberOfOcrThreads);
 
             OcrImageFactory ocrImageFactory = new OcrImageFactory(document,
                     documentFile,

ocr-service-v1/ocr-service-processor/src/main/java/com/knecon/fforesight/service/ocr/processor/service/threads/ImageExtractionThread.java

@@ -5,10 +5,10 @@ import java.util.List;
 import java.util.concurrent.BlockingQueue;
 
 import org.apache.pdfbox.Loader;
-import org.apache.pdfbox.io.MemoryUsageSetting;
 import org.apache.pdfbox.pdmodel.PDDocument;
 import org.apache.pdfbox.pdmodel.PDPage;
 
+import com.knecon.fforesight.service.ocr.processor.model.ExtractedImage;
 import com.knecon.fforesight.service.ocr.processor.model.ExtractedOcrImage;
 import com.knecon.fforesight.service.ocr.processor.model.OcrImage;
 import com.knecon.fforesight.service.ocr.processor.service.ImageStreamEngine;
@@ -26,6 +26,7 @@ import lombok.experimental.FieldDefaults;
 @FieldDefaults(makeFinal = true, level = AccessLevel.PRIVATE)
 public class ImageExtractionThread extends Thread {
 
+    static double FULL_PAGE_IMAGE_THRESHOLD = 0.98;
     static double IMAGE_ALIGNMENT_THRESHOLD = 1;
 
     int id;
@@ -40,6 +41,7 @@ public class ImageExtractionThread extends Thread {
     BlockingQueue<OcrImage> imageOutputQueue;
     List<Integer> stitchedPageNumbers;
 
+
     @SneakyThrows
     @Override
     public void run() {
@@ -48,20 +50,21 @@ public class ImageExtractionThread extends Thread {
         for (Integer pageIndex : pageIndices) {
             try (PDDocument document = Loader.loadPDF(documentFile)) { // load new PDDocument for thread safety, also keeps RAM usage low.
                 timestamp = System.currentTimeMillis();
-                List<ExtractedOcrImage> extractedOcrImages = getExtractedOcrImages(pageIndex, document);
+                List<ExtractedImage> extractedImages = getExtractedOcrImages(pageIndex, document);
                 stats.increaseImageExtraction(id, System.currentTimeMillis() - timestamp);
-                if (extractedOcrImages.isEmpty()) {
+                if (extractedImages.isEmpty()) {
                     logger.logPageSkipped(pageIndex);
                 }
 
-                if (checkForStitchedImages(extractedOcrImages)) {
+                if (checkForStitchedImages(extractedImages, document.getPage(pageIndex - 1))) {
                     stitchedPageNumbers.add(pageIndex);
                     logger.addImagesToProcess(pageIndex, 0);
                     continue;
                 }
 
-                for (ExtractedOcrImage image : extractedOcrImages) {
+                for (ExtractedImage image : extractedImages) {
-                    imageOutputQueue.put(image);
+                    ExtractedOcrImage ocrImage = new ExtractedOcrImage(image, settings.getDpi());
+                    imageOutputQueue.put(ocrImage);
                     logger.addImagesToProcess(image.getPageNumber(), image.getNumberOnPage());
                 }
             }
@@ -69,7 +72,7 @@ public class ImageExtractionThread extends Thread {
     }
 
 
-    private List<ExtractedOcrImage> getExtractedOcrImages(Integer pageIndex, PDDocument document) {
+    private List<ExtractedImage> getExtractedOcrImages(Integer pageIndex, PDDocument document) {
 
         PDPage page = document.getPage(pageIndex - 1);
         ImageStreamEngine imageStreamEngine = new ImageStreamEngine(settings);
@@ -79,22 +82,22 @@ public class ImageExtractionThread extends Thread {
 
 
     @SneakyThrows
-    private boolean checkForStitchedImages(List<ExtractedOcrImage> imagesOnCurrentPage) {
+    private boolean checkForStitchedImages(List<ExtractedImage> imagesOnCurrentPage, PDPage page) {
 
-        if (imagesOnCurrentPage.size() <= 1) {
+        if (imagesOnCurrentPage.isEmpty()) {
             return false;
         }
 
-        //checking for intersections or direct alignment of images
+        for (ExtractedImage imageOnPage : imagesOnCurrentPage) {
-        ExtractedOcrImage[] imageOnPagesArray = new ExtractedOcrImage[imagesOnCurrentPage.size()];
+            if (imageOnPage.getImageCoordinatesInInitialUserSpace().size() > FULL_PAGE_IMAGE_THRESHOLD * page.getCropBox().getHeight() * page.getCropBox().getWidth()) {
-        int index = 0;
+                return true;
-        for (ExtractedOcrImage imageOnPage : imagesOnCurrentPage) {
+            }
-            imageOnPagesArray[index] = imageOnPage;
-            index++;
         }
-        for (int j = 0; j < imageOnPagesArray.length; j++) {
+
-            for (int i = j + 1; i < imageOnPagesArray.length; i++) {
+        //checking for intersections or direct alignment of images
-                if (imageOnPagesArray[j].getImageCoordinatesInInitialUserSpace().aligns(imageOnPagesArray[i].getImageCoordinatesInInitialUserSpace(), IMAGE_ALIGNMENT_THRESHOLD)) {
+        for (int j = 0; j < imagesOnCurrentPage.size(); j++) {
+            for (int i = j + 1; i < imagesOnCurrentPage.size(); i++) {
+                if (imagesOnCurrentPage.get(j).getImageCoordinatesInInitialUserSpace().aligns(imagesOnCurrentPage.get(i).getImageCoordinatesInInitialUserSpace(), IMAGE_ALIGNMENT_THRESHOLD)) {
                     // TODO: see if we can stitch aligning images using BufferedImage and skip the gs conversion entirely
                     return true;
                 }

ocr-service-v1/ocr-service-processor/src/main/java/com/knecon/fforesight/service/ocr/processor/service/threads/OCRThread.java

@@ -1,6 +1,10 @@
 package com.knecon.fforesight.service.ocr.processor.service.threads;
 
 import static net.sourceforge.tess4j.ITessAPI.TRUE;
+import static net.sourceforge.tess4j.TessAPI1.TessBaseAPICreate;
+import static net.sourceforge.tess4j.TessAPI1.TessBaseAPIInit1;
+import static net.sourceforge.tess4j.TessAPI1.TessBaseAPISetPageSegMode;
+import static net.sourceforge.tess4j.TessAPI1.TessBaseAPISetVariable;
 
 import java.io.File;
 import java.nio.FloatBuffer;
@@ -16,6 +20,7 @@ import com.knecon.fforesight.service.ocr.processor.model.OcrResult;
 import com.knecon.fforesight.service.ocr.processor.service.OcrProgressLogger;
 import com.knecon.fforesight.service.ocr.processor.service.Statistics;
 import com.knecon.fforesight.service.ocr.processor.utils.Tesseract2;
+import com.sun.jna.StringArray;
 import com.sun.jna.ptr.PointerByReference;
 
 import lombok.AccessLevel;
@@ -42,8 +47,8 @@ public class OCRThread extends Thread {
     OcrProgressLogger logger;
     Statistics stats;
     OcrServiceSettings settings;
-    Tesseract2 instance;
     ITessAPI.TessBaseAPI detectionScriptHandle;
+    ITessAPI.TessBaseAPI tesseractHandle;
 
 
     public OCRThread(int id,
@@ -61,8 +66,8 @@ public class OCRThread extends Thread {
         this.logger = logger;
         this.stats = stats;
         this.settings = settings;
-        this.instance = createInstance(settings);
         this.detectionScriptHandle = initDetectionScriptHandle();
+        this.tesseractHandle = initTesseractHandle(settings);
     }
 
 
@@ -88,9 +93,9 @@ public class OCRThread extends Thread {
             }
         } catch (NoSuchElementException e) {
             log.debug("Processed all Images, finishing.");
+            TessAPI1.TessBaseAPIDelete(this.detectionScriptHandle);
+            TessAPI1.TessBaseAPIDelete(this.tesseractHandle);
         }
-
-        TessAPI1.TessBaseAPIDelete(this.detectionScriptHandle);
     }
 
 
@@ -107,10 +112,8 @@ public class OCRThread extends Thread {
         Pix rotatedPix = image.getRotatedPix();
         executeTesseract(psm, image.getDpi(), rotatedPix, tesseractOutputFileName);
 
-        synchronized (OCRThread.class) {
+        image.destroyPix();
-            image.destroyPix();
+        LeptUtils.disposePix(rotatedPix);
-            LeptUtils.disposePix(rotatedPix);
-        }
 
         results.add(OcrResult.create(image, tesseractOutputFileName));
         logger.logImageFinished(image, psm);
@@ -145,21 +148,37 @@ public class OCRThread extends Thread {
             orient_deg = orientationDegreeResultBuffer.get();
         }
 
-        synchronized (OCRThread.class) {
+        TessAPI1.TessBaseAPIClear(detectionScriptHandle);
-            TessAPI1.TessBaseAPIClear(detectionScriptHandle);
-        }
 
         return orient_deg;
     }
 
 
-    synchronized private static ITessAPI.TessBaseAPI initDetectionScriptHandle() {
+    private static ITessAPI.TessBaseAPI initDetectionScriptHandle() {
 
-        ITessAPI.TessBaseAPI handle = TessAPI1.TessBaseAPICreate();
+        synchronized (OCRThread.class) {
-        String datapath = System.getenv("TESSDATA_PREFIX");
-        TessAPI1.TessBaseAPIInit3(handle, datapath, "osd");
 
-        return handle;
+            ITessAPI.TessBaseAPI handle = TessBaseAPICreate();
+            String datapath = System.getenv("TESSDATA_PREFIX");
+//            TessBaseAPISetVariable(handle, "debug_file", "/dev/null");
+            TessAPI1.TessBaseAPIInit3(handle, datapath, "osd");
+
+            return handle;
+        }
+    }
+
+
+    synchronized private static ITessAPI.TessBaseAPI initTesseractHandle(OcrServiceSettings settings) {
+
+        synchronized (OCRThread.class) {
+
+            ITessAPI.TessBaseAPI handle = TessBaseAPICreate();
+            String datapath = System.getenv("TESSDATA_PREFIX");
+//            TessBaseAPISetVariable(handle, "debug_file", "/dev/null");
+            TessBaseAPIInit1(handle, datapath, settings.getLanguages(), 1, new PointerByReference(), 0);
+
+            return handle;
+        }
     }
 
 
@@ -173,19 +192,14 @@ public class OCRThread extends Thread {
             Leptonica1.pixWrite(folder + "/pix_" + a[a.length - 1] + ".png", pix, 3);
         }
 
-        instance.setVariable("user_defined_dpi", String.valueOf(dpi));
+        TessBaseAPISetPageSegMode(tesseractHandle, psm);
-        instance.setPageSegMode(psm);
-        instance.createDocumentsWithResults(pix, null, tesseractOutputFileName, List.of(ITesseract.RenderedFormat.HOCR), ITessAPI.TessPageIteratorLevel.RIL_BLOCK);
-    }
 
-
+        Tesseract2.createDocumentsWithResults(pix,
-    private static Tesseract2 createInstance(OcrServiceSettings settings) {
+                null,
-
+                tesseractOutputFileName,
-        Tesseract2 instance = new Tesseract2();
+                List.of(ITesseract.RenderedFormat.HOCR),
-        instance.setVariable("debug_file", "/dev/null"); // remove warnings from std out
+                ITessAPI.TessPageIteratorLevel.RIL_BLOCK,
-        instance.setOcrEngineMode(1); // set to LSTM based Engine
+                tesseractHandle);
-        instance.setLanguage(settings.getLanguages());
-        return instance;
     }
 
 }

ocr-service-v1/ocr-service-processor/src/main/java/com/knecon/fforesight/service/ocr/processor/settings/OcrServiceSettings.java

@@ -12,9 +12,9 @@ import lombok.experimental.FieldDefaults;
 @FieldDefaults(level = AccessLevel.PRIVATE)
 public class OcrServiceSettings {
 
-    int ocrThreadCount = 4; // Number of OCR threads
+    int ocrThreadCount = 16; // Number of OCR threads
-    int imageExtractThreadCount = 2; // Number of image extraction threads
+    int imageExtractThreadCount = 5; // Number of image extraction threads
-    int gsProcessCount = 2; // Number of Ghostscript processes
+    int gsProcessCount = 5; // Number of Ghostscript processes
     int dpi = 300; // Target DPI for binarized images
     int psmOverride = -1; // Overrides the page segmentation mode if > 0
     int minImageHeight = 20; // Minimum height for images to be processed

ocr-service-v1/ocr-service-processor/src/main/java/com/knecon/fforesight/service/ocr/processor/utils/Tesseract2.java

@@ -1,45 +1,54 @@
 package com.knecon.fforesight.service.ocr.processor.utils;
 
+import static net.sourceforge.tess4j.ITesseract.DOCUMENT_TITLE;
+
 import java.awt.Rectangle;
 import java.nio.IntBuffer;
 import java.util.ArrayList;
 import java.util.List;
 
+import com.knecon.fforesight.service.ocr.processor.service.threads.OCRThread;
 import com.sun.jna.Pointer;
 
+import lombok.experimental.UtilityClass;
 import lombok.extern.slf4j.Slf4j;
 import net.sourceforge.lept4j.Pix;
+import net.sourceforge.tess4j.ITessAPI;
+import net.sourceforge.tess4j.ITesseract;
 import net.sourceforge.tess4j.OCRResult;
 import net.sourceforge.tess4j.TessAPI1;
-import net.sourceforge.tess4j.Tesseract1;
-import net.sourceforge.tess4j.TesseractException;
 import net.sourceforge.tess4j.Word;
 
 @Slf4j
 /**
  * Overriden version only so I can use Tesseract1 with Pixs instead of BufferedImages. All Functions are copied and then the BufferedImage -> Pix conversion deleted.
  */
-public class Tesseract2 extends Tesseract1 {
+@UtilityClass
+public class Tesseract2 extends TessAPI1 {
 
+    private int createDocuments(Pix pix, String filename, ITessAPI.TessBaseAPI handle, ITessAPI.TessResultRenderer renderer) {
 
-    private int createDocuments(Pix pix, String filename, TessResultRenderer renderer) {
+        String title = TessBaseAPIGetStringVariable(handle, DOCUMENT_TITLE);
-
-        String title = TessBaseAPIGetStringVariable(getHandle(), DOCUMENT_TITLE);
         TessResultRendererBeginDocument(renderer, title);
-        int result = TessBaseAPIProcessPage(getHandle(), pix, 0, filename, null, 0, renderer);
+        int result = TessBaseAPIProcessPage(handle, pix, 0, filename, null, 0, renderer);
         TessResultRendererEndDocument(renderer);
 
 //        if (result == ITessAPI.FALSE) {
 //            throw new TesseractException("Error during processing page.");
 //        }
 
-        return TessBaseAPIMeanTextConf(getHandle());
+        return TessBaseAPIMeanTextConf(handle);
     }
 
 
-    public OCRResult createDocumentsWithResults(Pix bi, String filename, String outputbase, List<RenderedFormat> formats, int pageIteratorLevel) throws TesseractException {
+    public OCRResult createDocumentsWithResults(Pix bi,
+                                                String filename,
+                                                String outputbase,
+                                                List<ITesseract.RenderedFormat> formats,
+                                                int pageIteratorLevel,
+                                                ITessAPI.TessBaseAPI handle) {
 
-        List<OCRResult> results = createDocumentsWithResults(new Pix[]{bi}, new String[]{filename}, new String[]{outputbase}, formats, pageIteratorLevel);
+        List<OCRResult> results = createDocumentsWithResults(new Pix[]{bi}, new String[]{filename}, new String[]{outputbase}, formats, pageIteratorLevel, handle);
         if (!results.isEmpty()) {
             return results.get(0);
         } else {
@@ -48,24 +57,26 @@ public class Tesseract2 extends Tesseract1 {
     }
 
 
-    public List<OCRResult> createDocumentsWithResults(Pix[] pixs, String[] filenames, String[] outputbases, List<RenderedFormat> formats, int pageIteratorLevel) {
+    public List<OCRResult> createDocumentsWithResults(Pix[] pixs,
+                                                      String[] filenames,
+                                                      String[] outputbases,
+                                                      List<ITesseract.RenderedFormat> formats,
+                                                      int pageIteratorLevel,
+                                                      ITessAPI.TessBaseAPI handle) {
 
         if (pixs.length != filenames.length || pixs.length != outputbases.length) {
             throw new RuntimeException("The three arrays must match in length.");
         }
 
-        init();
-        setVariables();
-
         List<OCRResult> results = new ArrayList<OCRResult>();
 
         try {
             for (int i = 0; i < pixs.length; i++) {
                 try {
-                    TessResultRenderer renderer = createRenderers(outputbases[i], formats);
+                    ITessAPI.TessResultRenderer renderer = createRenderers(outputbases[i], formats);
-                    int meanTextConfidence = createDocuments(pixs[i], filenames[i], renderer);
+                    int meanTextConfidence = createDocuments(pixs[i], filenames[i], handle, renderer);
                     TessDeleteResultRenderer(renderer);
-                    List<Word> words = meanTextConfidence > 0 ? getRecognizedWords(pageIteratorLevel) : new ArrayList<Word>();
+                    List<Word> words = meanTextConfidence > 0 ? getRecognizedWords(pageIteratorLevel, handle) : new ArrayList<Word>();
                     results.add(new OCRResult(meanTextConfidence, words));
                 } catch (Exception e) {
                     // skip the problematic image file
@@ -73,20 +84,22 @@ public class Tesseract2 extends Tesseract1 {
                 }
             }
         } finally {
-            dispose();
+            synchronized (OCRThread.class) {
+                TessAPI1.TessBaseAPIClear(handle);
+            }
         }
 
         return results;
     }
 
 
-    private List<Word> getRecognizedWords(int pageIteratorLevel) {
+    private List<Word> getRecognizedWords(int pageIteratorLevel, ITessAPI.TessBaseAPI handle) {
 
         List<Word> words = new ArrayList<>();
 
         try {
-            TessResultIterator ri = TessBaseAPIGetIterator(getHandle());
+            ITessAPI.TessResultIterator ri = TessBaseAPIGetIterator(handle);
-            TessPageIterator pi = TessResultIteratorGetPageIterator(ri);
+            ITessAPI.TessPageIterator pi = TessResultIteratorGetPageIterator(ri);
             TessPageIteratorBegin(pi);
 
             do {
@@ -119,11 +132,11 @@ public class Tesseract2 extends Tesseract1 {
     }
 
 
-    private TessResultRenderer createRenderers(String outputbase, List<RenderedFormat> formats) {
+    private ITessAPI.TessResultRenderer createRenderers(String outputbase, List<ITesseract.RenderedFormat> formats) {
 
-        TessResultRenderer renderer = null;
+        ITessAPI.TessResultRenderer renderer = null;
 
-        for (RenderedFormat format : formats) {
+        for (ITesseract.RenderedFormat format : formats) {
             switch (format) {
 
                 case HOCR:

ocr-service-v1/ocr-service-server/src/test/java/com/knecon/fforesight/service/ocr/v1/server/OcrServiceIntegrationTest.java

@@ -31,7 +31,7 @@ import io.micrometer.prometheus.PrometheusMeterRegistry;
 import io.micrometer.prometheus.PrometheusTimer;
 import lombok.SneakyThrows;
 
-@Disabled // Ghostscript/Tesseract/Leptonica is not available on build server. If you want to run the test install these dependencies. See README.md for help.
+//@Disabled // Ghostscript/Tesseract/Leptonica is not available on build server. If you want to run the test install these dependencies. See README.md for help.
 @SpringBootTest()
 public class OcrServiceIntegrationTest extends AbstractTest {
 
@@ -64,7 +64,7 @@ public class OcrServiceIntegrationTest extends AbstractTest {
     @SneakyThrows
     public void testOcr() {
 
-        String text = testOCR("files/2009-1048395_50pages_tables.pdf");
+        String text = testOCR("files/VV-352892.pdf");
     }
 
 
@@ -139,7 +139,7 @@ public class OcrServiceIntegrationTest extends AbstractTest {
 
         String dir = "/home/kschuettler/Dokumente/TestFiles/syn-dm-testfiles/";
         List<File> foundFiles = Files.walk(Path.of(dir))
-                .sorted(Comparator.comparingLong(this::getFileSize))
+//                .sorted(Comparator.comparingLong(this::getFileSize))
                 .map(Path::toFile)
                 .filter(file -> file.getName().endsWith(".pdf"))
                 .peek(System.out::println)
@@ -162,7 +162,7 @@ public class OcrServiceIntegrationTest extends AbstractTest {
     @SneakyThrows
     public void testOcrForSpecificFile() {
 
-        testOCRForFile(new File("/home/kschuettler/Dokumente/TestFiles/syn-dm-testfiles/F.2. A16003E - Acute Inhalation Study.pdf"));
+        testOCRForFile(new File("/home/kschuettler/Dokumente/TestFiles/syn-dm-testfiles/Item 17_Toxicidade Inalatoria.pdf"));
 //        testOCRForFile(new File("/home/kschuettler/Dokumente/TestFiles/syn-dm-testfiles/A23220A - 404 - Skin Irritation in vivo.pdf"));
 //        testOCRForFile(new File("/home/kschuettler/Dokumente/TestFiles/OcrMassTest/G.1.2 - 1768300_MMNA_A13617AV_report.pdf"));
 //        testOCRForFile(new File("/home/kschuettler/Dokumente/TestFiles/OcrMassTest/SOLICITA_VICTRATO-GOLD-II_Item 17_Toxicidade Inalatoria Aguda.pdf"));