1 files changed, 120 insertions, 0 deletions
diff --git a/src/main/java/info/selflearner/ocr_telegram/util/OCR.java b/src/main/java/info/selflearner/ocr_telegram/util/OCR.java
new file mode 100644
index 0000000..55e577f
--- /dev/null
+++ b/src/main/java/info/selflearner/ocr_telegram/util/OCR.java
@@ -0,0 +1,120 @@
+package info.selflearner.ocr_telegram.util;
+
+import info.selflearner.ocr_telegram.exception.PassportNotFoundException;
+import info.selflearner.ocr_telegram.model.Passport;
+import net.sourceforge.tess4j.*;
+import net.sourceforge.tess4j.util.LoadLibs;
+import org.json.JSONArray;
+import org.json.JSONObject;
+
+import javax.imageio.ImageIO;
+import java.awt.*;
+import java.awt.geom.AffineTransform;
+import java.awt.image.AffineTransformOp;
+import java.awt.image.BufferedImage;
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+
+public class OCR {
+    private static final ITesseract TESSERACT = new Tesseract();
+
+    static {
+        TESSERACT.setDatapath("src/main/resources/tessdata/");
+        TESSERACT.setVariable("user_defined_dpi", "300");
+        System.setProperty("java.library.path", LoadLibs.extractTessResources("win32-x86-64").getPath());
+    }
+
+    public static String perform(File file, String languages) throws TesseractException {
+        TESSERACT.setLanguage(languages);
+        String ocrResult = TESSERACT.doOCR(file);
+        file.delete();
+        return ocrResult;
+    }
+
+    public static Passport performPassport(File file) throws IOException, InterruptedException, PassportNotFoundException {
+        for (int imageRotateAngle = 0; imageRotateAngle <= 270; imageRotateAngle += 90) {
+            if (imageRotateAngle == 90) {
+                System.out.println("Rotating image to 90 degrees...");
+                rotateImageVertically(file, true);
+            } else if (imageRotateAngle == 180) {
+                System.out.println("Rotating image to 180 degrees...");
+                rotateImageHorizontally(file);
+            } else if (imageRotateAngle == 270) {
+                System.out.println("Rotating image to 270 degrees...");
+                rotateImageVertically(file, false);
+            }
+
+            Runtime.getRuntime().exec(new String[]{"surya_ocr", file.getPath(), "--results_dir", System.getProperty("java.io.tmpdir"), "--langs=en"}).waitFor();
+            JSONArray jsonTextLines = new JSONObject(Files.readAllLines(Path.of(System.getProperty("java.io.tmpdir"), "/", file.getName().split("\\.")[0], "/results.json")).getFirst())
+                    .getJSONArray(file.getName().split("\\.")[0]).getJSONObject(0).getJSONArray("text_lines");
+            int mrzStartingIndex = -1;
+
+            for (int arrayIndex = 0; arrayIndex < jsonTextLines.length() && mrzStartingIndex == -1; arrayIndex++) {
+                if (jsonTextLines.getJSONObject(arrayIndex).getString("text").indexOf("P<") == 0) {
+                    mrzStartingIndex = arrayIndex;
+                }
+            }
+
+            if (mrzStartingIndex != -1) {
+                System.out.println("MRZ1: " + jsonTextLines.getJSONObject(mrzStartingIndex).getString("text"));
+                System.out.println("MRZ2: " + jsonTextLines.getJSONObject(mrzStartingIndex + 1).getString("text"));
+                try {
+                    return new Passport(new String[]{jsonTextLines.getJSONObject(mrzStartingIndex).getString("text"), jsonTextLines.getJSONObject(mrzStartingIndex + 1).getString("text")},
+                            new int[]{(int) (jsonTextLines.getJSONObject(mrzStartingIndex).getDouble("confidence") * 100), (int) (jsonTextLines.getJSONObject(mrzStartingIndex + 1).getDouble("confidence") * 100)});
+                } catch (Exception _) {
+
+                }
+            }
+        }
+        throw new PassportNotFoundException("Passport not found");
+    }
+
+    private static void rotateImageVertically(File image, boolean counterClockwise) throws IOException {
+        BufferedImage bufferedImage = ImageIO.read(image);
+        BufferedImage output = new BufferedImage(bufferedImage.getHeight(), bufferedImage.getWidth(), bufferedImage.getType());
+
+        AffineTransform affineTransform = getAffineTransform(counterClockwise, bufferedImage);
+
+        AffineTransformOp affineTransformOp = new AffineTransformOp(affineTransform, AffineTransformOp.TYPE_BILINEAR);
+        affineTransformOp.filter(bufferedImage, output);
+
+        ImageIO.write(output, "jpg", image);
+    }
+
+    public static void rotateImageHorizontally(File image) throws IOException {
+        BufferedImage imageToRotate = ImageIO.read(image);
+
+        int widthOfImage = imageToRotate.getWidth();
+        int heightOfImage = imageToRotate.getHeight();
+        int typeOfImage = imageToRotate.getType();
+
+        BufferedImage output = new BufferedImage(widthOfImage, heightOfImage, typeOfImage);
+
+        Graphics2D graphics2D = output.createGraphics();
+
+        graphics2D.rotate(Math.toRadians(180), widthOfImage / 2.0, heightOfImage / 2.0);
+        graphics2D.drawImage(imageToRotate, null, 0, 0);
+
+        ImageIO.write(output, "jpg", image);
+    }
+
+    private static AffineTransform getAffineTransform(boolean counterClockwise, BufferedImage bufferedImage) {
+        int imageWidth = bufferedImage.getWidth();
+        int imageHeight = bufferedImage.getHeight();
+
+        AffineTransform affineTransform = new AffineTransform();
+        affineTransform.rotate((!counterClockwise ? Math.PI : -Math.PI) / 2, imageWidth / 2.0, imageHeight / 2.0);
+
+        double offset = (imageWidth - imageHeight) / 2.0;
+        if (!counterClockwise) {
+            affineTransform.translate(offset, offset);
+        } else {
+            affineTransform.translate(-offset, -offset);
+        }
+        return affineTransform;
+    }
+
+}
+