Android ขอความช่วยเหลือ ตัวโค้ดเกิดความผิดพลาด อยากทราบวิธีแก้ไข

public class CameraActivity extends Activity implements CamOpenOverCallback,Camera.PreviewCallback {
    private static final String TAG = "yanzi";
    CameraSurfaceView surfaceView = null;
    ImageButton shutterBtn;
    TextView tvColorHEX;
    float previewRate = -1f;
    private int[] pixels;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Thread openThread = new Thread() {
            @Override
            public void run() {
                // TODO Auto-generated method stub
                CameraInterface.getInstance().doOpenCamera(CameraActivity.this);
            }
        };
        openThread.start();
        setContentView(R.layout.activity_camera);
        initUI();
        initViewParams();

        shutterBtn.setOnClickListener(new BtnListeners());
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        return true;
    }

    private void initUI() {
        surfaceView = (CameraSurfaceView) findViewById(R.id.camera_surfaceview);
        shutterBtn = (ImageButton) findViewById(R.id.btn_shutter);
        tvColorHEX = (TextView) findViewById(R.id.tv_color_HEX);
    }

    private void initViewParams() {
        LayoutParams params = surfaceView.getLayoutParams();
        Point p = DisplayUtil.getScreenMetrics(this);
        params.width = p.x;
        params.height = p.y;
        previewRate = DisplayUtil.getScreenRate(this);
        surfaceView.setLayoutParams(params);
        pixels = new int[params.width * params.height];
        LayoutParams p2 = shutterBtn.getLayoutParams();
        p2.width = DisplayUtil.dip2px(this, 80);
        p2.height = DisplayUtil.dip2px(this, 80);

        shutterBtn.setLayoutParams(p2);
    }

    @Override
    public void cameraHasOpened() {
        // TODO Auto-generated method stub
        SurfaceHolder holder = surfaceView.getSurfaceHolder();
        CameraInterface.getInstance().setPreviewCallback(this);
        CameraInterface.getInstance().doStartPreview(holder, previewRate);
    }

    private class BtnListeners implements OnClickListener {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            switch (v.getId()) {
                case R.id.btn_shutter:
                    CameraInterface.getInstance().doTakePicture();
                    break;
                default:
                    break;
            }
        }
    }

    @Override
    public void onPreviewFrame(byte[] data, Camera camera) {
        if (pixels == null) return;
        Point p = DisplayUtil.getScreenMetrics(this);
        decodeYUV420SP(pixels, data, p.x, p.y);
        String a = Integer.toHexString(pixels[pixels.length / 2 + p.y / 2]);
        String b1 = a.substring(2, 8);
        String c = b1;
        int b2 = Integer.parseInt(b1, 16);

        if (b2 >= 0xffffff) {
            c = "ขาว White";
        }
        if (b2 >= 0xffff00 && b2 <= 0xffffff) {
            c = "เหลือง Yellow";
        }
        if (b2 >= 0xff00ff && b2 <= 0xffff00) {
            c = "ม่วง Violet";
        }
        if (b2 >= 0xff0000 && b2 <= 0xff00ff) {
            c = "แดง Red";
        }
        if (b2 >= 0x00ffff && b2 <= 0xff0000) {
            c = "ฟ้า Lightblue";
        }
        if (b2 >= 0x00ff00 && b2 <= 0x00ffff) {
            c = "เขียว Green";
        }
        if (b2 >= 0x0000ff && b2 <= 0x00ff00) {
            c = "น้ำเงิน Blue";
        }
        if (b2 >= 0x000000 && b2 <= 0x0000ff) {
            c = "สีดำ Black";
        }


        tvColorHEX.setText(c);

    }

    void decodeYUV420SP(int[] rgb, byte[] yuv420sp, int width, int height) {
        final int frameSize = width * height;
        for (int j = 0, yp = 0; j < height; j++) {
            int uvp = frameSize + (j >> 1) * width, u = 0, v = 0;
            for (int i = 0; i < width; i++, yp++) {
                int y = (0xff & ((int) yuv420sp[yp])) - 16;
                if (y < 0)
                    y = 0;
                if ((i & 1) == 0) {
                    v = (0xff & yuv420sp[uvp++]) - 128;
                    u = (0xff & yuv420sp[uvp++]) - 128;
                }
                int y1192 = 1192 * y;
                int r = (y1192 + 1634 * v);
                int g = (y1192 - 833 * v - 400 * u);
                int b = (y1192 + 2066 * u);

                if (r < 0)
                    r = 0;
                else if (r > 262143)
                    r = 262143;
                if (g < 0)
                    g = 0;
                else if (g > 262143)
                    g = 262143;
                if (b < 0)
                    b = 0;
                else if (b > 262143)
                    b = 262143;

                rgb[yp] = 0xff000000 | ((r << 6) & 0xff0000)
                        | ((g >> 2) & 0xff00) | ((b >> 10) & 0xff);
                //rgb[yp] = 0xff000000 | ((r << 6) & 0xff0000)
                //| ((g >> 2) & 0xff00) | ((b >> 10) & 0xff);
            }
        }
    }

}