content: /*
   * Copyright 2009 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 com.google.zxing.camera;
  
  import android.graphics.Bitmap;
  
  import com.google.zxing.LuminanceSource;
  
  /**
   * This object extends LuminanceSource around an array of YUV data returned from the camera driver,
   * with the option to crop to a rectangle within the full data. This can be used to exclude
   * superfluous pixels around the perimeter and speed up decoding.
   *
   * It works for any pixel format where the Y channel is planar and appears first, including
   * YCbCr_420_SP and YCbCr_422_SP.
   *
   * @author dswitkin@google.com (Daniel Switkin)
   */
  public final class PlanarYUVLuminanceSource extends LuminanceSource {
    private final byte[] yuvData;
    private final int dataWidth;
    private final int dataHeight;
    private final int left;
    private final int top;
  
    public PlanarYUVLuminanceSource(byte[] yuvData, int dataWidth, int dataHeight, int left, int top,
        int width, int height) {
      super(width, height);
  
      if (left + width > dataWidth || top + height > dataHeight) {
        throw new IllegalArgumentException("Crop rectangle does not fit within image data.");
      }
  
      this.yuvData = yuvData;
      this.dataWidth = dataWidth;
      this.dataHeight = dataHeight;
      this.left = left;
      this.top = top;
    }
  
    @Override
    public byte[] getRow(int y, byte[] row) {
      if (y < 0 || y >= getHeight()) {
        throw new IllegalArgumentException("Requested row is outside the image: " + y);
      }
      int width = getWidth();
      if (row == null || row.length < width) {
        row = new byte[width];
      }
      int offset = (y + top) * dataWidth + left;
      System.arraycopy(yuvData, offset, row, 0, width);
      return row;
    }
  
    @Override
    public byte[] getMatrix() {
      int width = getWidth();
      int height = getHeight();
  
      // If the caller asks for the entire underlying image, save the copy and give them the
      // original data. The docs specifically warn that result.length must be ignored.
      if (width == dataWidth && height == dataHeight) {
        return yuvData;
      }
  
      int area = width * height;
      byte[] matrix = new byte[area];
      int inputOffset = top * dataWidth + left;
  
      // If the width matches the full width of the underlying data, perform a single copy.
      if (width == dataWidth) {
        System.arraycopy(yuvData, inputOffset, matrix, 0, area);
        return matrix;
      }
  
      // Otherwise copy one cropped row at a time.
      byte[] yuv = yuvData;
      for (int y = 0; y < height; y++) {
        int outputOffset = y * width;
        System.arraycopy(yuv, inputOffset, matrix, outputOffset, width);
        inputOffset += dataWidth;
      }
      return matrix;
    }
  
    @Override
    public boolean isCropSupported() {
      return true;
    }
  
    public int getDataWidth() {
      return dataWidth;
    }
  
    public int getDataHeight() {
      return dataHeight;
    }
  
    public Bitmap renderCroppedGreyscaleBitmap() {
      int width = getWidth();
      int height = getHeight();
      int[] pixels = new int[width * height];
      byte[] yuv = yuvData;
      int inputOffset = top * dataWidth + left;
  
      for (int y = 0; y < height; y++) {
        int outputOffset = y * width;
        for (int x = 0; x < width; x++) {
          int grey = yuv[inputOffset + x] & 0xff;
          pixels[outputOffset + x] = 0xFF000000 | (grey * 0x00010101);
        }
        inputOffset += dataWidth;
      }
  
      Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
      bitmap.setPixels(pixels, 0, width, 0, 0, width, height);
      return bitmap;
    }
  }
  