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;
      }
  }
  