RED-7669: optimize OCR-module performance

* move all critical stuff to its own singleton thread
* make gs process queue any image once the file has been written

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

@@ -16,20 +16,8 @@ import lombok.experimental.FieldDefaults;
 import net.sourceforge.lept4j.Pix;
 import net.sourceforge.lept4j.util.LeptUtils;
 
-@Getter
+public record ExtractedImage(
-@RequiredArgsConstructor
+        int pageNumber, QuadPoint position, int height, int width, BufferedImage image, Matrix ctm, int numberOnPage, PDColorSpace colorSpace) implements UnprocessedImage {
-@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;
-
 
     @SneakyThrows
     public Pix asPix() {

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

@@ -63,7 +63,7 @@ public class ImageExtractionThread extends Thread {
 
                 for (ExtractedImage image : extractedImages) {
                     imageProcessingQueue.put((UnprocessedImage) image);
-                    logger.addImagesToProcess(image.getPageNumber(), image.getNumberOnPage());
+                    logger.addImagesToProcess(image.pageNumber(), image.numberOnPage());
                 }
             }
         }
@@ -87,7 +87,7 @@ public class ImageExtractionThread extends Thread {
         }
 
         for (ExtractedImage imageOnPage : imagesOnCurrentPage) {
-            if (imageOnPage.getWidth() > FULL_PAGE_IMAGE_THRESHOLD * page.getCropBox().getWidth() && imageOnPage.getHeight() > FULL_PAGE_IMAGE_THRESHOLD * page.getCropBox().getHeight()) {
+            if (imageOnPage.width() > FULL_PAGE_IMAGE_THRESHOLD * page.getCropBox().getWidth() && imageOnPage.height() > FULL_PAGE_IMAGE_THRESHOLD * page.getCropBox().getHeight()) {
                 return true;
             }
         }

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

@@ -2,7 +2,6 @@ package com.knecon.fforesight.service.ocr.processor.service.threads;
 
 import static net.sourceforge.tess4j.ITessAPI.TRUE;
 
-import java.lang.annotation.Documented;
 import java.nio.FloatBuffer;
 import java.nio.IntBuffer;
 import java.util.ArrayList;
@@ -28,7 +27,6 @@ import lombok.RequiredArgsConstructor;
 import lombok.SneakyThrows;
 import lombok.experimental.FieldDefaults;
 import lombok.extern.slf4j.Slf4j;
-import net.sourceforge.lept4j.Leptonica1;
 import net.sourceforge.lept4j.Pix;
 import net.sourceforge.lept4j.util.LeptUtils;
 import net.sourceforge.tess4j.ITessAPI;
@@ -107,44 +105,39 @@ public class ImageProcessingThread extends Thread {
 
     private OcrImage processRenderedPageImageFile(RenderedPageImageFile renderedPageImageFile) {
 
-        Pix grayScale = ImageProcessingUtils.convertToGrayScale(renderedPageImageFile.asPix());
+        Pix pix = binarize(renderedPageImageFile.asPix(), settings.getDpi(), settings.getDpi());
-        Pix despeckled = ImageProcessingUtils.despecklePix(grayScale);
 
-        int orientDegree = detectOrientation(despeckled, settings.getDpi(), detectionScriptHandle);
+        int orientDegree = detectOrientation(pix, settings.getDpi(), detectionScriptHandle);
-        Pix rotatedPix = switch (360 - orientDegree) {
+        Pix rotatedPix = ImageProcessingUtils.deRotatePix(orientDegree, pix);
-            case 90 -> Leptonica1.pixRotateOrth(despeckled, 1);
-            case 180 -> Leptonica1.pixRotateOrth(despeckled, 2);
-            case 270 -> Leptonica1.pixRotateOrth(despeckled, 3);
-            default -> despeckled;
-        };
 
-        OcrImage ocrImage = new RenderedPageOcrImage(despeckled.h,
+        OcrImage ocrImage = new RenderedPageOcrImage(pix.h,
-                despeckled.w,
+                pix.w,
                 PageInformation.fromPDPage(renderedPageImageFile.pageNumber(), document.getPage(renderedPageImageFile.pageNumber() - 1)),
                 rotatedPix,
                 orientDegree);
 
-        if (despeckled != rotatedPix) {
+        if (pix != rotatedPix) {
-            LeptUtils.disposePix(despeckled);
+            LeptUtils.disposePix(pix);
         }
+
         return ocrImage;
     }
 
 
     private OcrImage processExtractedImage(ExtractedImage extractedImage) {
 
-        float imageDPI = Math.abs(extractedImage.getImage().getWidth() / (extractedImage.getCtm().getScalingFactorX() / 72));
+        float imageDPI = Math.abs(extractedImage.image().getWidth() / (extractedImage.ctm().getScalingFactorX() / 72));
 
         Pix pix = binarize(extractedImage.asPix(), imageDPI, settings.getDpi());
 
         int orientDegree = detectOrientation(pix, settings.getDpi(), detectionScriptHandle);
-        Pix rotatedPix = getRotatedPix(orientDegree, pix);
+        Pix rotatedPix = ImageProcessingUtils.deRotatePix(orientDegree, pix);
 
-        OcrImage ocrImage = new ExtractedOcrImage(extractedImage.getPageNumber(),
+        OcrImage ocrImage = new ExtractedOcrImage(extractedImage.pageNumber(),
-                extractedImage.getNumberOnPage(),
+                extractedImage.numberOnPage(),
-                extractedImage.getHeight(),
+                extractedImage.height(),
-                extractedImage.getWidth(),
+                extractedImage.width(),
-                extractedImage.getCtm(),
+                extractedImage.ctm(),
                 rotatedPix,
                 pix.h,
                 pix.w,
@@ -157,15 +150,6 @@ public class ImageProcessingThread extends Thread {
     }
 
 
-    private static Pix getRotatedPix(int orientDegree, Pix pix) {
-
-        return switch (360 - orientDegree) {
-            case 90 -> Leptonica1.pixRotateOrth(pix, 1);
-            case 180 -> Leptonica1.pixRotateOrth(pix, 2);
-            case 270 -> Leptonica1.pixRotateOrth(pix, 3);
-            default -> pix;
-        };
-    }
 
 
     static public int detectOrientation(Pix pix, int dpi, ITessAPI.TessBaseAPI detectionScriptHandle) {

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

@@ -24,10 +24,10 @@ public class ImageProcessingUtils {
     public BufferedImage convertToDeviceColorSpace(ExtractedImage extractedImage) {
 
         BufferedImage image;
-        if (extractedImage.getColorSpace() instanceof PDDeviceRGB || extractedImage.getColorSpace() instanceof PDDeviceGray) {
+        if (extractedImage.colorSpace() instanceof PDDeviceRGB || extractedImage.colorSpace() instanceof PDDeviceGray) {
-            image = extractedImage.getImage();
+            image = extractedImage.image();
         } else {
-            BufferedImage pdfImage = extractedImage.getImage();
+            BufferedImage pdfImage = extractedImage.image();
             image = new BufferedImage(pdfImage.getWidth(), pdfImage.getHeight(), BufferedImage.TYPE_BYTE_GRAY);
             Graphics g = image.getGraphics();
             g.drawImage(pdfImage, 0, 0, null);
@@ -98,6 +98,17 @@ public class ImageProcessingUtils {
     }
 
 
+    public Pix deRotatePix(int orientDegree, Pix pix) {
+
+        return switch (360 - orientDegree) {
+            case 90 -> Leptonica1.pixRotateOrth(pix, 1);
+            case 180 -> Leptonica1.pixRotateOrth(pix, 2);
+            case 270 -> Leptonica1.pixRotateOrth(pix, 3);
+            default -> pix;
+        };
+    }
+
+
     public static void setAlphaChannelToWhite(BufferedImage image) {
 
         if (image.getTransparency() == Transparency.TRANSLUCENT) {

ocr-service-v1/ocr-service-processor/src/test/java/com/knecon/fforesight/service/ocr/processor/utils/ImageProcessingUtilsTest.java

@@ -0,0 +1,34 @@
+package com.knecon.fforesight.service.ocr.processor.utils;
+
+import static net.sourceforge.lept4j.ILeptonica.IFF_PNG;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import net.sourceforge.lept4j.Leptonica1;
+import net.sourceforge.lept4j.Pix;
+
+class ImageProcessingUtilsTest {
+
+    @BeforeEach
+    public void loadLeptonica() {
+
+        System.setProperty("jna.library.path", System.getenv("VCPKG_DYNAMIC_LIB"));
+    }
+
+
+    @Test
+    public void testRotation() {
+
+        Pix pix = Leptonica1.pixRead("/home/kschuettler/Downloads/painHarold.webp");
+        Pix pix2 = ImageProcessingUtils.deRotatePix(0, pix);
+        Leptonica1.pixWrite("/tmp/0.png", pix2, IFF_PNG);
+        Pix pix3 = ImageProcessingUtils.deRotatePix(90, pix);
+        Leptonica1.pixWrite("/tmp/90.png", pix3, IFF_PNG);
+        Pix pix4 = ImageProcessingUtils.deRotatePix(180, pix);
+        Leptonica1.pixWrite("/tmp/180.png", pix4, IFF_PNG);
+        Pix pix5 = ImageProcessingUtils.deRotatePix(270, pix);
+        Leptonica1.pixWrite("/tmp/270.png", pix5, IFF_PNG);
+    }
+
+}