Android人脸识别Demo竖屏YUV方向调整和图片保存

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());
        }
    }