Question

我想通过计算从相机传入的两帧之间的差异来检测移动，并在手机屏幕上显示这种差异。我必须覆盖OnCameraFrame()方法，所以我做了：

  @Override
    public Mat onCameraFrame(Mat inputFrame) {
        inputFrame.copyTo(current);
        Core.absdiff(current, previous, difference);
        current.copyTo(previous);
        return difference;
    }

但不幸的是app崩溃了，我得到了：

06-13 18:17:30.000: E/cv::error()(13097): OpenCV Error: Sizes of input arguments do not match (The operation is neither 'array op array' (where arrays have the same size and the same number of channels), nor 'array op scalar', nor 'scalar op array') in void cv::arithm_op(cv::InputArray, cv::InputArray, cv::OutputArray, cv::InputArray, int, void (**)(const uchar*, size_t, const uchar*, size_t, uchar*, size_t, cv::Size, void*), bool, void*), file /home/reports/ci/slave/50-SDK/opencv/modules/core/src/arithm.cpp, line 1277
06-13 18:17:30.005: W/dalvikvm(13097): threadid=11: thread exiting with uncaught exception (group=0x411df2a0)
06-13 18:17:30.005: E/AndroidRuntime(13097): FATAL EXCEPTION: Thread-983
06-13 18:17:30.005: E/AndroidRuntime(13097): CvException [org.opencv.core.CvException: /home/reports/ci/slave/50-SDK/opencv/modules/core/src/arithm.cpp:1277: error: (-209) The operation is neither 'array op array' (where arrays have the same size and the same number of channels), nor 'array op scalar', nor 'scalar op array' in function void cv::arithm_op(cv::InputArray, cv::InputArray, cv::OutputArray, cv::InputArray, int, void (**)(const uchar*, size_t, const uchar*, size_t, uchar*, size_t, cv::Size, void*), bool, void*)

完整的类代码是：

   package com.example.szpieg2;

import org.opencv.android.BaseLoaderCallback;
import org.opencv.android.CameraBridgeViewBase;
import org.opencv.android.CameraBridgeViewBase.CvCameraViewListener;
import org.opencv.android.LoaderCallbackInterface;
import org.opencv.android.OpenCVLoader;
import org.opencv.core.Core;
import org.opencv.core.CvType;
import org.opencv.core.Mat;
import org.opencv.core.Range;
import org.opencv.core.Size;

import android.app.Activity;
import android.content.pm.ActivityInfo;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.Window;
import android.view.WindowManager;

public class TrackActivity extends Activity implements CvCameraViewListener {
    private Mat current;
    private CameraBridgeViewBase cameraView;
    private Mat previous;
    private Mat difference;//difference between previous and current
    private BaseLoaderCallback mLoaderCallback = new BaseLoaderCallback(this) {
        @Override
        public void onManagerConnected(int status) {
            switch (status) {
            case LoaderCallbackInterface.SUCCESS: {
                Log.i("Co sie dzieje?", "OpenCV loaded successfully");
                cameraView.enableView();
                // cameraView.setOnTouchListener(ColorBlobDetectionActivity.this);
            }
                break;
            default: {
                super.onManagerConnected(status);
            }
                break;
            }
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
        setContentView(R.layout.activity_track);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
        cameraView = (CameraBridgeViewBase) findViewById(R.id.surface_view);
        cameraView.setCvCameraViewListener(this);
    }

    // --------Activity Actions---------
    @Override
    public void onPause() {
        if (cameraView != null)
            cameraView.disableView();
        super.onPause();
    }

    @Override
    public void onResume() {
        super.onResume();
        OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION_2_4_3, this,
                mLoaderCallback);
    }

    public void onDestroy() {
        super.onDestroy();
        if (cameraView != null)
            cameraView.disableView();
    }

    // --------/Activity Actions/---------

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.activity_track, menu);
        return true;
    }

    // --------listener method implementation-------------
    @Override
    public void onCameraViewStarted(int width, int height) {
        previous = new Mat(width, height, CvType.CV_64FC4);
        current = new Mat(width, height, CvType.CV_64FC4);
        difference = new Mat(width, height, CvType.CV_64FC4);
    }

    @Override
    public void onCameraViewStopped() {
        current.release();

    }

    @Override
    public Mat onCameraFrame(Mat inputFrame) {
        inputFrame.copyTo(current);
        Core.absdiff(current, previous, difference);
        current.copyTo(previous);
        return difference;
    }

}

修改我已经在设备上安装了openCV usign openCV manager。添加到OpenCV的所有教程都在使用该设备。该设备是三星Galaxy Note 2.图书馆项目使用的是OpenCV 2.4.3，这个必须留下来。

[/ EDIT]

Answer 1

问题已经统一Mat previous。所以：

@Override
public Mat onCameraFrame(Mat inputFrame) {
    inputFrame.copyTo(current);
    if(first){//first is true at the first time
        inputFrame.copyTo(previous);
        first = false;
        Log.i("First processing", "Pierwszy przebieg");
    }

    Core.absdiff(current, previous, difference);
//  current.copyTo(previous);
    inputFrame.copyTo(previous);

    return difference;
}

如何计算相机2个输入帧之间的差异（开放CV）

1 个答案: