Android人脸识别Demo竖屏YUV方向调整和图片保存(分享)

本博客包含三个常用方法，用于盛开Android版人脸识别Demo中竖屏使用时送入yuv数据，但一直无法识别的情况。

1.首先可以尝试顺时针旋转90°或270°，然后送入识别SDK。

2.旋转方向后依然无法识别时，可以尝试saveImg( )，保存本地检查图片是否符合要求。

/**
 * 视频顺时针旋转90
 * 该方法仅仅在竖屏时候使用
 * */
public static byte[] rotateYUV420Degree90(byte[] data, int imageWidth,
         int imageHeight) {
 byte[] yuv = new byte[imageWidth * imageHeight * 3 / 2];
 int i = 0;
 for (int x = 0; x < imageWidth; x++) {
  for (int y = imageHeight - 1; y >= 0; y--) {
   yuv[i] = data[y * imageWidth + x];
   i++;
  }
 }
 i = imageWidth * imageHeight * 3 / 2 - 1;
 for (int x = imageWidth - 1; x > 0; x = x - 2) {
  for (int y = 0; y < imageHeight / 2; y++) {
   yuv[i] = data[(imageWidth * imageHeight) + (y * imageWidth) + x];
   i--;
   yuv[i] = data[(imageWidth * imageHeight) + (y * imageWidth)
     + (x - 1)];
   i--;
  }
 }
 return yuv;
}

public static byte[] YUV420spRotate270(byte[] src, int width, int height) {
 int count = 0;
 int uvHeight = height >> 1;
 int imgSize = width * height;
 byte[] des = new byte[imgSize * 3 >> 1];
 //copy y
 for (int j = width - 1; j >= 0; j--) {
  for (int i = 0; i < height; i++) {
   des[count++] = src[width * i + j];
  }
 }
 //u,v
 for (int j = width - 1; j > 0; j -= 2) {
  for (int i = 0; i < uvHeight; i++) {
   des[count++] = src[imgSize + width * i + j - 1];
   des[count++] = src[imgSize + width * i + j];
  }
 }
 return des;
}
private int i = 1;
private String path = Environment.getExternalStorageDirectory().getAbsolutePath() + "/0Face/";
private Calendar now = new GregorianCalendar();
private SimpleDateFormat simpleDate = new SimpleDateFormat("yyyyMMddHHmmss", Locale.getDefault());
private String fileName = simpleDate.format(now.getTime());

/**
 * @param data yuv图像数据
 * @param width
 * @param height
 */
public void saveImg(byte[] data, int width, int height) {
 File dir = new File(path);
 if (!dir.exists()) dir.mkdirs();
 File f = new File(path + (fileName + "-" + i++) + ".jpg");
 FileOutputStream fOut = null;
 try {
  //yuv转成bitmap
  YuvImage image = new YuvImage(data, ImageFormat.NV21, width, height, null);
  ByteArrayOutputStream stream = new ByteArrayOutputStream();
  image.compressToJpeg(new Rect(0, 0, width, height), 80, stream);
  Bitmap bmp = BitmapFactory.decodeByteArray(stream.toByteArray(), 0, stream.size());
  //bitmap保存至本地
  fOut = new FileOutputStream(f);
  bmp.compress(Bitmap.CompressFormat.JPEG, 100, fOut);
  fOut.flush();
  fOut.close();
  bmp.recycle();
  stream.close();
 } catch (Exception ex) {
  Log.e("Sys", "Error:" + ex.getMessage());
 }
}

来源：http://blog.csdn.net/iblade/article/details/78835467