位圖在Android和墊在OpenCV中

Question

我有這樣的代碼在OpenCV的C++：

#include <opencv2/imgproc/imgproc.hpp> 
#include <opencv2/highgui/highgui.hpp> 

using namespace cv; 

int main(){ 
    Mat src = imread("image.jpg"); 
    if (src.empty()) 
     return -1; 
    pyrMeanShiftFiltering(src,src,10,20,1); 
    imshow("src", src); 
    waitKey(0); 
    return 0; 
} 

而來自OpenCV的2.4.2爲一個名爲 「OpenCV的教程1 - 添加OpenCV的」 樣本此Sample1View.java類：

import org.opencv.android.Utils; 
import org.opencv.core.Core; 
import org.opencv.core.CvType; 
import org.opencv.core.Mat; 
import org.opencv.core.Point; 
import org.opencv.core.Scalar; 
import org.opencv.imgproc.Imgproc; 
import android.content.Context; 
import android.graphics.Bitmap; 
import android.util.Log; 

class Sample1View extends SampleViewBase { 
    public static final int  VIEW_MODE_RGBA = 0; 
    public static final int  VIEW_MODE_GRAY = 1; 
    public static final int  VIEW_MODE_CANNY = 2; 
    private Mat mYuv; 
    private Mat mRgba; 
    private Mat mGraySubmat; 
    private Mat mIntermediateMat; 
    private Bitmap mBitmap; 
    private int mViewMode; 

    public Sample1View(Context context) { 
     super(context); 
     mViewMode = VIEW_MODE_RGBA; 
    } 

    @Override 
    protected void onPreviewStarted(int previewWidth, int previewHeight) { 
     synchronized (this) { 
      // initialize Mats before usage 
      mYuv = new Mat(getFrameHeight() + getFrameHeight()/2, getFrameWidth(), CvType.CV_8UC1); 
      mGraySubmat = mYuv.submat(0, getFrameHeight(), 0, getFrameWidth()); 
      mRgba = new Mat(); 
      mIntermediateMat = new Mat(); 
      mBitmap = Bitmap.createBitmap(previewWidth, previewHeight, Bitmap.Config.ARGB_8888); 
     } 
    } 

    @Override 
    protected void onPreviewStopped() { 
     if(mBitmap != null) { 
      mBitmap.recycle(); 
     } 

     synchronized (this) { 
      // Explicitly deallocate Mats 
      if (mYuv != null) 
       mYuv.release(); 
      if (mRgba != null) 
       mRgba.release(); 
      if (mGraySubmat != null) 
       mGraySubmat.release(); 
      if (mIntermediateMat != null) 
       mIntermediateMat.release(); 
      mYuv = null; 
      mRgba = null; 
      mGraySubmat = null; 
      mIntermediateMat = null; 
     } 
    } 

    @Override 
    protected Bitmap processFrame(byte[] data) { 
     mYuv.put(0, 0, data); 
     final int viewMode = mViewMode; 

     switch (viewMode) { 
     case VIEW_MODE_GRAY: 
      Imgproc.cvtColor(mGraySubmat, mRgba, Imgproc.COLOR_GRAY2RGBA, 4); 
      break; 
     case VIEW_MODE_RGBA: 
      Imgproc.cvtColor(mYuv, mRgba, Imgproc.COLOR_YUV420sp2RGB, 4); 
      Core.putText(mRgba, "OpenCV + Android", new Point(10, 100), 3/* CV_FONT_HERSHEY_COMPLEX */, 2, new Scalar(255, 0, 0, 255), 3); 
      break; 
     case VIEW_MODE_CANNY: 
      Imgproc.Canny(mGraySubmat, mIntermediateMat, 80, 100); 
      Imgproc.cvtColor(mIntermediateMat, mRgba, Imgproc.COLOR_GRAY2BGRA, 4); 
      break; 
     } 

     Bitmap bmp = mBitmap; 

     try { 
      Utils.matToBitmap(mRgba, bmp); 
     } catch(Exception e) { 
      Log.e("org.opencv.samples.tutorial1", "Utils.matToBitmap() throws an exception: " + e.getMessage()); 
      bmp.recycle(); 
      bmp = null; 
     } 
     return bmp; 
    } 

    public void setViewMode(int viewMode) { 
     mViewMode = viewMode; 
    } 
} 

現在我想我的代碼在Android上工作，所以我代替這一行：

case VIEW_MODE_GRAY: 
    Imgproc.cvtColor(mGraySubmat, mRgba, Imgproc.COLOR_GRAY2RGBA, 4); 
    break; 

這樣：

case VIEW_MODE_GRAY: 
    Imgproc.cvtColor(mGraySubmat, mRgba, Imgproc.COLOR_GRAY2RGBA, 4); 
    Imgproc.pyrMeanShiftFiltering(mRgba,mRgba,10,20); 
    break; 

，但我得到這個：

10-20 11:08:45.929: I/Sample::Activity(12846): Menu Item selected Preview GRAY 
10-20 11:08:46.049: W/dalvikvm(12846): threadid=9: thread exiting with uncaught exception (group=0x4013a560) 
10-20 11:08:46.059: E/AndroidRuntime(12846): FATAL EXCEPTION: Thread-10 
10-20 11:08:46.059: E/AndroidRuntime(12846): CvException [org.opencv.core.CvException: ..\..\modules\imgproc\src\segmentation.cpp:345: error: (-210) Only 8-bit, 3-channel images are supported in function void cvPyrMeanShiftFiltering(const CvArr*, CvArr*, double, double, int, CvTermCriteria) 
10-20 11:08:46.059: E/AndroidRuntime(12846): ] 
10-20 11:08:46.059: E/AndroidRuntime(12846): at org.opencv.imgproc.Imgproc.pyrMeanShiftFiltering_1(Native Method) 
10-20 11:08:46.059: E/AndroidRuntime(12846): at org.opencv.imgproc.Imgproc.pyrMeanShiftFiltering(Imgproc.java:7247) 
10-20 11:08:46.059: E/AndroidRuntime(12846): at com.duckie.a.Sample1View.processFrame(Sample1View.java:80) 
10-20 11:08:46.059: E/AndroidRuntime(12846): at com.duckie.a.SampleViewBase.run(SampleViewBase.java:185) 
10-20 11:08:46.059: E/AndroidRuntime(12846): at java.lang.Thread.run(Thread.java:1019) 

出了什麼問題？我如何讓我的代碼在Android中工作？而且，如何在不拖延的情況下做到這一點？

Answer 1

看來cvPyrMeanShiftFiltering期待一個3通道圖像和你生成一個4通道圖像：

Imgproc.cvtColor(mGraySubmat, mRgba, Imgproc.COLOR_GRAY2RGBA, 4);