DecodeHandler.java

/*
 * Copyright (C) 2010 ZXing authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.ovirt.mobile.movirt.camera;

import android.graphics.Bitmap;
import android.os.Bundle;
import android.os.Handler;
import android.os.Looper;
import android.os.Message;
import android.util.Log;

import com.google.zxing.BinaryBitmap;
import com.google.zxing.PlanarYUVLuminanceSource;
import com.google.zxing.ReaderException;
import com.google.zxing.Result;
import com.google.zxing.client.android.R;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.datamatrix.DataMatrixReader;

import org.ovirt.mobile.movirt.ui.CameraActivity;

import java.io.ByteArrayOutputStream;

/**
 * modified by Nika
 */
final class DecodeHandler extends Handler {

    private static final String TAG = DecodeHandler.class.getSimpleName();

    private final CameraActivity activity;
    private final DataMatrixReader dataMatrixReader;
    private boolean running = true;

    DecodeHandler(CameraActivity activity) {
        dataMatrixReader = new DataMatrixReader();
        this.activity = activity;
    }

    private static void bundleThumbnail(PlanarYUVLuminanceSource source, Bundle bundle) {
        int[] pixels = source.renderThumbnail();
        int width = source.getThumbnailWidth();
        int height = source.getThumbnailHeight();
        Bitmap bitmap = Bitmap.createBitmap(pixels, 0, width, width, height, Bitmap.Config.ARGB_8888);
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        bitmap.compress(Bitmap.CompressFormat.JPEG, 50, out);
        bundle.putByteArray(DecodeThread.BARCODE_BITMAP, out.toByteArray());
        bundle.putFloat(DecodeThread.BARCODE_SCALED_FACTOR, (float) width / source.getWidth());
    }

    @Override
    public void handleMessage(Message message) {
        if (!running) {
            return;
        }
        switch (message.what) {
            case R.id.zxing_decode:
                decode((byte[]) message.obj, message.arg1, message.arg2);
                break;
            case R.id.zxing_back_button:
                running = false;
                Looper.myLooper().quit();
                break;
        }
    }

    /**
     * Decode the data within the viewfinder rectangle, and time how long it took. For efficiency,
     * reuse the same reader objects from one decode to the next.
     *
     * @param data   The YUV preview frame.
     * @param width  The width of the preview frame.
     * @param height The height of the preview frame.
     */
    private void decode(byte[] data, int width, int height) {
        long start = System.currentTimeMillis();
        Result rawResult = null;
        PlanarYUVLuminanceSource source = activity.getCameraManager().buildLuminanceSource(data, width, height);
        if (source != null) {
            BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
            try {
                rawResult = dataMatrixReader.decode(bitmap);
            } catch (ReaderException re) {
                // continue
            } finally {
                dataMatrixReader.reset();
            }
        }

        Handler handler = activity.getHandler();
        if (rawResult != null) {
            // Don't log the barcode contents for security.
            long end = System.currentTimeMillis();
            Log.d(TAG, "Found barcode in " + (end - start) + " ms");
            if (handler != null) {
                Message message = Message.obtain(handler, R.id.zxing_decode_succeeded, rawResult);
                Bundle bundle = new Bundle();
                bundleThumbnail(source, bundle);
                message.setData(bundle);
                message.sendToTarget();
            }
        } else {
            if (handler != null) {
                Message message = Message.obtain(handler, R.id.zxing_decode_failed);
                message.sendToTarget();
            }
        }
    }
}