Try harder to find QR codes in image files

And refactor a bit by moving some of the QR scanning related logic to a
separate helper class.

app/src/main/java/com/beemdevelopment/aegis/helpers/QrCodeAnalyzer.java

@@ -9,19 +9,11 @@ import androidx.annotation.NonNull;
 import androidx.camera.core.ImageAnalysis;
 import androidx.camera.core.ImageProxy;
 
-import com.google.zxing.BarcodeFormat;
-import com.google.zxing.BinaryBitmap;
-import com.google.zxing.DecodeHintType;
-import com.google.zxing.MultiFormatReader;
 import com.google.zxing.NotFoundException;
 import com.google.zxing.PlanarYUVLuminanceSource;
 import com.google.zxing.Result;
-import com.google.zxing.common.HybridBinarizer;
 
 import java.nio.ByteBuffer;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.Map;
 
 public class QrCodeAnalyzer implements ImageAnalysis.Analyzer {
     private static final String TAG = QrCodeAnalyzer.class.getSimpleName();
@@ -59,14 +51,8 @@ public class QrCodeAnalyzer implements ImageAnalysis.Analyzer {
                 false
         );
 
-        MultiFormatReader reader = new MultiFormatReader();
-        BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
         try {
-            Map<DecodeHintType, Object> hints = new HashMap<>();
+            Result result = QrCodeHelper.decodeFromSource(source);
-            hints.put(DecodeHintType.POSSIBLE_FORMATS, Collections.singletonList(BarcodeFormat.QR_CODE));
-            hints.put(DecodeHintType.ALSO_INVERTED, true);
-
-            Result result = reader.decode(bitmap, hints);
             if (_listener != null) {
                 _listener.onQrCodeDetected(result);
             }

app/src/main/java/com/beemdevelopment/aegis/helpers/QrCodeHelper.java

@@ -0,0 +1,96 @@
+package com.beemdevelopment.aegis.helpers;
+
+import android.graphics.Bitmap;
+import android.graphics.BitmapFactory;
+import android.graphics.Color;
+
+import androidx.annotation.ColorInt;
+
+import com.google.zxing.BarcodeFormat;
+import com.google.zxing.BinaryBitmap;
+import com.google.zxing.DecodeHintType;
+import com.google.zxing.LuminanceSource;
+import com.google.zxing.MultiFormatReader;
+import com.google.zxing.NotFoundException;
+import com.google.zxing.RGBLuminanceSource;
+import com.google.zxing.Result;
+import com.google.zxing.WriterException;
+import com.google.zxing.common.BitMatrix;
+import com.google.zxing.common.HybridBinarizer;
+import com.google.zxing.qrcode.QRCodeWriter;
+
+import java.io.InputStream;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
+public class QrCodeHelper {
+    private QrCodeHelper() {
+
+    }
+
+    public static Result decodeFromSource(LuminanceSource source) throws NotFoundException {
+        Map<DecodeHintType, Object> hints = new HashMap<>();
+        hints.put(DecodeHintType.POSSIBLE_FORMATS, Collections.singletonList(BarcodeFormat.QR_CODE));
+        hints.put(DecodeHintType.ALSO_INVERTED, true);
+
+        BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
+        MultiFormatReader reader = new MultiFormatReader();
+        return reader.decode(bitmap, hints);
+    }
+
+    public static Result decodeFromStream(InputStream inStream) throws DecodeError {
+        BitmapFactory.Options bmOptions = new BitmapFactory.Options();
+        Bitmap bitmap = BitmapFactory.decodeStream(inStream, null, bmOptions);
+        if (bitmap == null) {
+            throw new DecodeError("Unable to decode stream to bitmap");
+        }
+
+        // If ZXing is not able to decode the image on the first try, we try a couple of
+        // more times with smaller versions of the same image.
+        for (int i = 0; i <= 2; i++) {
+            if (i != 0) {
+                bitmap = BitmapHelper.resize(bitmap, bitmap.getWidth() / (i * 2), bitmap.getHeight() / (i * 2));
+            }
+
+            try {
+                int[] pixels = new int[bitmap.getWidth() * bitmap.getHeight()];
+                bitmap.getPixels(pixels, 0, bitmap.getWidth(), 0, 0, bitmap.getWidth(), bitmap.getHeight());
+
+                LuminanceSource source = new RGBLuminanceSource(bitmap.getWidth(), bitmap.getHeight(), pixels);
+                return decodeFromSource(source);
+            } catch (NotFoundException ignored) {
+
+            }
+        }
+
+        throw new DecodeError(NotFoundException.getNotFoundInstance());
+    }
+
+    public static Bitmap encodeToBitmap(String data, int width, int height, @ColorInt int backgroundColor) throws WriterException {
+        QRCodeWriter writer = new QRCodeWriter();
+        BitMatrix bitMatrix = writer.encode(data, BarcodeFormat.QR_CODE, width, height);
+
+        int[] pixels = new int[width * height];
+        for (int y = 0; y < height; y++) {
+            int offset = y * width;
+            for (int x = 0; x < width; x++) {
+                pixels[offset + x] = bitMatrix.get(x, y) ? Color.BLACK : backgroundColor;
+            }
+        }
+
+        Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
+        bitmap.setPixels(pixels, 0, width, 0, 0, width, height);
+        return bitmap;
+    }
+
+    public static class DecodeError extends Exception {
+        public DecodeError(String message) {
+            super(message);
+        }
+
+        public DecodeError(Throwable cause) {
+            super(cause);
+        }
+    }
+}

app/src/main/java/com/beemdevelopment/aegis/ui/MainActivity.java

@@ -5,8 +5,6 @@ import android.content.ClipData;
 import android.content.ClipboardManager;
 import android.content.Context;
 import android.content.Intent;
-import android.graphics.Bitmap;
-import android.graphics.BitmapFactory;
 import android.net.Uri;
 import android.os.Bundle;
 import android.provider.Settings;
@@ -26,32 +24,19 @@ import com.beemdevelopment.aegis.Preferences;
 import com.beemdevelopment.aegis.R;
 import com.beemdevelopment.aegis.SortCategory;
 import com.beemdevelopment.aegis.ViewMode;
-import com.beemdevelopment.aegis.helpers.BitmapHelper;
 import com.beemdevelopment.aegis.helpers.FabScrollHelper;
 import com.beemdevelopment.aegis.helpers.PermissionHelper;
-import com.beemdevelopment.aegis.helpers.QrCodeAnalyzer;
 import com.beemdevelopment.aegis.otp.GoogleAuthInfo;
 import com.beemdevelopment.aegis.otp.GoogleAuthInfoException;
 import com.beemdevelopment.aegis.ui.dialogs.Dialogs;
 import com.beemdevelopment.aegis.ui.fragments.preferences.BackupsPreferencesFragment;
 import com.beemdevelopment.aegis.ui.fragments.preferences.PreferencesFragment;
+import com.beemdevelopment.aegis.ui.tasks.QrDecodeTask;
 import com.beemdevelopment.aegis.ui.views.EntryListView;
 import com.beemdevelopment.aegis.vault.VaultEntry;
 import com.google.android.material.bottomsheet.BottomSheetDialog;
 import com.google.android.material.floatingactionbutton.FloatingActionButton;
-import com.google.zxing.BinaryBitmap;
-import com.google.zxing.ChecksumException;
-import com.google.zxing.FormatException;
-import com.google.zxing.LuminanceSource;
-import com.google.zxing.NotFoundException;
-import com.google.zxing.RGBLuminanceSource;
-import com.google.zxing.Reader;
-import com.google.zxing.Result;
-import com.google.zxing.common.HybridBinarizer;
-import com.google.zxing.qrcode.QRCodeReader;
 
-import java.io.IOException;
-import java.io.InputStream;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
@@ -326,37 +311,25 @@ public class MainActivity extends AegisActivity implements EntryListView.Listene
     }
 
     private void onScanImageResult(Intent intent) {
-        decodeQrCodeImage(intent.getData());
+        startDecodeQrCodeImage(intent.getData());
     }
 
-    private void decodeQrCodeImage(Uri inputFile) {
+    private void startDecodeQrCodeImage(Uri uri) {
-        Bitmap bitmap;
+        QrDecodeTask task = new QrDecodeTask(this, (result) -> {
-
+            if (result.getException() != null) {
-        try {
+                Dialogs.showErrorDialog(this, R.string.unable_to_read_qrcode, result.getException());
-            BitmapFactory.Options bmOptions = new BitmapFactory.Options();
+                return;
-
-            try (InputStream inputStream = getContentResolver().openInputStream(inputFile)) {
-                bitmap = BitmapFactory.decodeStream(inputStream, null, bmOptions);
-                bitmap = BitmapHelper.resize(bitmap, QrCodeAnalyzer.RESOLUTION.getWidth(), QrCodeAnalyzer.RESOLUTION.getHeight());
             }
 
-            int[] intArray = new int[bitmap.getWidth() * bitmap.getHeight()];
+            try {
-            bitmap.getPixels(intArray, 0, bitmap.getWidth(), 0, 0, bitmap.getWidth(), bitmap.getHeight());
+                GoogleAuthInfo info = GoogleAuthInfo.parseUri(result.getResult().getText());
-
+                VaultEntry entry = new VaultEntry(info);
-            LuminanceSource source = new RGBLuminanceSource(bitmap.getWidth(), bitmap.getHeight(), intArray);
+                startEditEntryActivityForNew(CODE_ADD_ENTRY, entry);
-            BinaryBitmap binaryBitmap = new BinaryBitmap(new HybridBinarizer(source));
+            } catch (GoogleAuthInfoException e) {
-
+                Dialogs.showErrorDialog(this, R.string.unable_to_read_qrcode, e);
-            Reader reader = new QRCodeReader();
+            }
-            Result result = reader.decode(binaryBitmap);
+        });
-
+        task.execute(getLifecycle(), uri);
-            GoogleAuthInfo info = GoogleAuthInfo.parseUri(result.getText());
-            VaultEntry entry = new VaultEntry(info);
-
-            startEditEntryActivityForNew(CODE_ADD_ENTRY, entry);
-        } catch (NotFoundException | IOException | ChecksumException | FormatException | GoogleAuthInfoException e) {
-            e.printStackTrace();
-            Dialogs.showErrorDialog(this, R.string.unable_to_read_qrcode, e);
-        }
     }
 
     private void updateSortCategoryMenu() {
@@ -471,7 +444,7 @@ public class MainActivity extends AegisActivity implements EntryListView.Listene
             intent.setAction(null);
             intent.removeExtra(Intent.EXTRA_STREAM);
 
-            decodeQrCodeImage(uri);
+            startDecodeQrCodeImage(uri);
         }
     }
 

app/src/main/java/com/beemdevelopment/aegis/ui/TransferEntriesActivity.java

@@ -15,12 +15,10 @@ import androidx.annotation.ColorInt;
 
 import com.beemdevelopment.aegis.R;
 import com.beemdevelopment.aegis.Theme;
+import com.beemdevelopment.aegis.helpers.QrCodeHelper;
 import com.beemdevelopment.aegis.otp.GoogleAuthInfo;
 import com.beemdevelopment.aegis.ui.dialogs.Dialogs;
-import com.google.zxing.BarcodeFormat;
 import com.google.zxing.WriterException;
-import com.google.zxing.common.BitMatrix;
-import com.google.zxing.qrcode.QRCodeWriter;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -104,22 +102,12 @@ public class TransferEntriesActivity extends AegisActivity {
         return true;
     }
 
-
     private void generateQR() {
         GoogleAuthInfo selectedEntry = _authInfos.get(_currentEntryCount - 1);
         _issuer.setText(selectedEntry.getIssuer());
         _accountName.setText(selectedEntry.getAccountName());
         _entriesCount.setText(getResources().getQuantityString(R.plurals.entries_count, _authInfos.size(), _currentEntryCount, _authInfos.size()));
 
-        QRCodeWriter writer = new QRCodeWriter();
-        BitMatrix bitMatrix;
-        try {
-            bitMatrix = writer.encode(selectedEntry.getUri().toString(), BarcodeFormat.QR_CODE, 512, 512);
-        } catch (WriterException e) {
-            Dialogs.showErrorDialog(this, R.string.unable_to_generate_qrcode, e);
-            return;
-        }
-
         @ColorInt int backgroundColor = Color.WHITE;
         if (getConfiguredTheme() == Theme.LIGHT) {
             TypedValue typedValue = new TypedValue();
@@ -127,18 +115,14 @@ public class TransferEntriesActivity extends AegisActivity {
             backgroundColor = typedValue.data;
         }
 
-        int width = bitMatrix.getWidth();
+        Bitmap bitmap;
-        int height = bitMatrix.getHeight();
+        try {
-        int[] pixels = new int[width * height];
+            bitmap = QrCodeHelper.encodeToBitmap(selectedEntry.getUri().toString(), 512, 512, backgroundColor);
-        for (int y = 0; y < height; y++) {
+        } catch (WriterException e) {
-            int offset = y * width;
+            Dialogs.showErrorDialog(this, R.string.unable_to_generate_qrcode, e);
-            for (int x = 0; x < width; x++) {
+            return;
-                pixels[offset + x] = bitMatrix.get(x, y) ? Color.BLACK : backgroundColor;
-            }
         }
 
-        Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
-        bitmap.setPixels(pixels, 0, width, 0, 0, width, height);
         _qrImage.setImageBitmap(bitmap);
     }
 }

app/src/main/java/com/beemdevelopment/aegis/ui/tasks/QrDecodeTask.java

@@ -0,0 +1,62 @@
+package com.beemdevelopment.aegis.ui.tasks;
+
+import android.content.Context;
+import android.net.Uri;
+
+import com.beemdevelopment.aegis.R;
+import com.beemdevelopment.aegis.helpers.QrCodeHelper;
+import com.google.zxing.Result;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+public class QrDecodeTask extends ProgressDialogTask<Uri, QrDecodeTask.Response> {
+    private final Callback _cb;
+
+    public QrDecodeTask(Context context, Callback cb) {
+        super(context, context.getString(R.string.analyzing_qr));
+        _cb = cb;
+    }
+
+    @Override
+    protected Response doInBackground(Uri... params) {
+        Context context = getDialog().getContext();
+
+        Uri uri = params[0];
+        try (InputStream inStream = context.getContentResolver().openInputStream(uri)) {
+            Result result = QrCodeHelper.decodeFromStream(inStream);
+            return new Response(result, null);
+        } catch (QrCodeHelper.DecodeError | IOException e) {
+            e.printStackTrace();
+            return new Response(null, e);
+        }
+    }
+
+    @Override
+    protected void onPostExecute(Response result) {
+        super.onPostExecute(result);
+        _cb.onTaskFinished(result);
+    }
+
+    public interface Callback {
+        void onTaskFinished(Response result);
+    }
+
+    public static class Response {
+        private final Result _result;
+        private final Exception _e;
+
+        public Response(Result result, Exception e) {
+            _result = result;
+            _e = e;
+        }
+
+        public Result getResult() {
+            return _result;
+        }
+
+        public Exception getException() {
+            return _e;
+        }
+    }
+}

app/src/main/res/values/strings.xml

@@ -156,6 +156,7 @@
     <string name="encrypting_vault">Encrypting the vault</string>
     <string name="exporting_vault">Exporting the vault</string>
     <string name="reading_file">Reading file</string>
+    <string name="analyzing_qr">Analyzing QR code</string>
     <string name="importing_icon_pack">Importing icon pack</string>
     <string name="delete_entry">Delete entry</string>
     <string name="delete_entry_description">Are you sure you want to delete this entry?</string>