Android Open Source - bitfynd-wallet-android Qr

• Back to Development/wallet  ↑

From Project

Back to project page bitfynd-wallet-android.

License

The source code is released under:

GNU General Public License

Java Source Code

/*
 * Copyright 2013-2014 the original author or authors.
 *//from   w ww  .  ja  v a  2  s  .co  m
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package de.schildbach.wallet.util;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Hashtable;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

import javax.annotation.Nonnull;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import android.graphics.Bitmap;
import android.graphics.Color;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.WriterException;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.qrcode.QRCodeWriter;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;

/**
 * @author Andreas Schildbach
 */
public class Qr
{
  private final static QRCodeWriter QR_CODE_WRITER = new QRCodeWriter();

  private static final Logger log = LoggerFactory.getLogger(Qr.class);

  public static Bitmap bitmap(@Nonnull final String content, final int size)
  {
    try
    {
      final Hashtable<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>();
      hints.put(EncodeHintType.MARGIN, 0);
      hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
      final BitMatrix result = QR_CODE_WRITER.encode(content, BarcodeFormat.QR_CODE, size, size, hints);

      final int width = result.getWidth();
      final int height = result.getHeight();
      final int[] pixels = new int[width * height];

      for (int y = 0; y < height; y++)
      {
        final int offset = y * width;
        for (int x = 0; x < width; x++)
        {
          pixels[offset + x] = result.get(x, y) ? Color.BLACK : Color.TRANSPARENT;
        }
      }

      final Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
      bitmap.setPixels(pixels, 0, width, 0, 0, width, height);
      return bitmap;
    }
    catch (final WriterException x)
    {
      log.info("problem creating qr code", x);
      return null;
    }
  }

  public static String encodeCompressBinary(@Nonnull final byte[] bytes)
  {
    try
    {
      final ByteArrayOutputStream bos = new ByteArrayOutputStream(bytes.length);
      final GZIPOutputStream gos = new GZIPOutputStream(bos);
      gos.write(bytes);
      gos.close();

      final byte[] gzippedBytes = bos.toByteArray();
      final boolean useCompressioon = gzippedBytes.length < bytes.length;

      final StringBuilder str = new StringBuilder();
      str.append(useCompressioon ? 'Z' : '-');
      str.append(Base43.encode(useCompressioon ? gzippedBytes : bytes));

      return str.toString();
    }
    catch (final IOException x)
    {
      throw new RuntimeException(x);
    }
  }

  public static String encodeBinary(@Nonnull final byte[] bytes)
  {
    return Base43.encode(bytes);
  }

  public static byte[] decodeDecompressBinary(@Nonnull final String content) throws IOException
  {
    final boolean useCompression = content.charAt(0) == 'Z';
    final byte[] bytes = Base43.decode(content.substring(1));

    InputStream is = new ByteArrayInputStream(bytes);
    if (useCompression)
      is = new GZIPInputStream(is);
    final ByteArrayOutputStream baos = new ByteArrayOutputStream();

    final byte[] buf = new byte[4096];
    int read;
    while (-1 != (read = is.read(buf)))
      baos.write(buf, 0, read);
    baos.close();
    is.close();

    return baos.toByteArray();
  }

  public static byte[] decodeBinary(@Nonnull final String content) throws IOException
  {
    return Base43.decode(content);
  }
}

Java Source Code List

• Back to Development/wallet  ↑