c++ - 实时视频上的 OpenCV Canny Edge

Question

我正在尝试对来自网络摄像头的实时视频实现 opencv 的 canny 边缘检测。但是，我收到此错误:

OpenCV 错误:未知函数中不支持的格式或格式组合 <>，文件 .......\ocv\opencv\src\cv\cvcanny.cpp，第 66 行

我想这是一个格式问题。我可以将 3 channel 8 位 RGB 图像转换为 1 channel 灰度图像帧，然后对结果进行边缘检测。但是，我也无法在图像上实现 rgb2grayscale 转换； <此转换代码的 channel 数不正确>

下面是我在 VS2008 中实现的代码。关于如何解决此错误的任何想法？

#pragma once

#include <stdio.h>
#include <tchar.h>
#include <iostream>
#include <conio.h>
#include <iomanip>
#include <cv.h>
#include <cvaux.h>
#include <cxcore.h>
#include <highgui.h>
#include <math.h>
#include <string.h>
#include <cxtypes.h>


using namespace std;
using namespace cv;

int main(int, char**)
{

    cvNamedWindow("Edges", CV_WINDOW_AUTOSIZE); 
CvCapture* capture = cvCaptureFromCAM(0);

IplImage* frame;
    while(1) {
        frame = cvQueryFrame( capture );


        int depth_img =frame->depth;
        int height_img =frame->height;
        int width_img =frame->width;
        int size_img =frame->imageSize;
        int nchan_img =frame->nChannels;
        int nsize_img =frame->nSize;

        cout << setw(15) << "depth" <<  depth_img << endl;
        cout << setw(15) << "height" <<  height_img << endl;
        cout << setw(15) << "width" <<  width_img << endl;
        cout << setw(15) << "size" <<  size_img << endl;
        cout << setw(15) << "nchan" <<  nchan_img << endl;
        cout << setw(15) << "nsize" <<  nsize_img << endl;


        IplImage* out = cvCreateImage( cvGetSize(frame), IPL_DEPTH_8U, 3 );
        cvSmooth( frame, out, CV_GAUSSIAN, 11, 11 );
        cvCvtColor(out ,out, CV_RGB2GRAY);
        cvCanny( out, out, 10, 10, 3 );

        if( !frame ) break;
        cvShowImage( "Edge", out );
        char c = cvWaitKey(33);
        if( c == 27 ) break;
    }
    cvReleaseCapture( &capture );
    cvDestroyWindow( "Edge" );
    return 0;
}

Answer 1

问题是你每时每刻都在传递一个 3 channel 图像

IplImage* out = cvCreateImage( cvGetSize(frame), IPL_DEPTH_8U, 3 );

创建另外两个单 channel 图像并使用它们:

IplImage* gray_out = cvCreateImage( cvGetSize(frame), IPL_DEPTH_8U, 1 );
IplImage* canny_out = cvCreateImage( cvGetSize(frame), IPL_DEPTH_8U, 1 );

并将其用于:

cvSmooth( frame, out, CV_GAUSSIAN, 11, 11 );
cvCvtColor(out , gray_out, CV_RGB2GRAY);
cvCanny( gray_out, canny_out, 10, 10, 3 );

if( !frame ) break;
cvShowImage( "Edge", canny_out );

这对我有用:

#include <stdio.h>
#include <iostream>
#include <iomanip>
#include <cv.h>
#include <cvaux.h>
#include <cxcore.h>
#include <highgui.h>
#include <math.h>
#include <string.h>


using namespace std;
using namespace cv;

int main(int, char**)
{

    cvNamedWindow("Edges", CV_WINDOW_AUTOSIZE); 
CvCapture* capture = cvCaptureFromCAM(0);

IplImage* frame;
    while(1) {
        frame = cvQueryFrame( capture );

        int depth_img =frame->depth;
        int height_img =frame->height;
        int width_img =frame->width;
        int size_img =frame->imageSize;
        int nchan_img =frame->nChannels;
        int nsize_img =frame->nSize;

        cout << setw(15) << "depth" <<  depth_img << endl;
        cout << setw(15) << "height" <<  height_img << endl;
        cout << setw(15) << "width" <<  width_img << endl;
        cout << setw(15) << "size" <<  size_img << endl;
        cout << setw(15) << "nchan" <<  nchan_img << endl;
        cout << setw(15) << "nsize" <<  nsize_img << endl;


        IplImage* out = cvCreateImage( cvGetSize(frame), IPL_DEPTH_8U, 3 );
        IplImage* gray_out = cvCreateImage( cvGetSize(frame), IPL_DEPTH_8U, 1 );
        IplImage* canny_out = cvCreateImage( cvGetSize(frame), IPL_DEPTH_8U, 1 );
        cvSmooth( frame, out, CV_GAUSSIAN, 11, 11 );
        cvCvtColor(out , gray_out, CV_RGB2GRAY);
        cvCanny( gray_out, canny_out, 10, 10, 3 );

        if( !frame ) break;
        cvShowImage( "Edge", canny_out );
        char c = cvWaitKey(33);
        if( c == 27 ) break;
    }
    cvReleaseCapture( &capture );
    cvDestroyWindow( "Edge" );
    return 0;
}