模板匹配屏幕截图在断言时失败 [英] Template Matching a screenshot fails on assertion

问题描述

我试图使用OpenCV进行屏幕截图的模板匹配。每当我调用 cv :: matchTemplate（）函数时，我收到一个错误。

I'm trying to use OpenCV for template matching of a screenshot. I'm getting an error whenever I call the cv::matchTemplate() function.

错误我得到：

OpenCv错误：Assertion失败（深度== CV_8U || depth == CV_32F）& ;& type == _templ.type（）&& _img.dims（）< = 2）in cv :: matchTemplate，file C：\builds\master_PackSlave-win64-vc12-shared\opencv\\ \\ modules\imgproc\src\templmatch.cpp

我尝试过的：

这个问题解决问题，但解决方案不帮助，因为这是我已经在做的。我已经双重检查调试器中的一切。没有任何内容为空，一切都有多个行和列和2个维度。

This question attempts to solve the problem but the solution doesn't help because that's what I'm already doing. I've double checked everything in the debugger. Nothing is NULL, everything has several rows and columns and 2 dimensions.

主

HWND handle = GetForegroundWindow();
cv::Mat mat;
if (handle != 0){
    mat = windowToMat(handle);
}
myTemplateMatch(mat, playerTemplate);

模板匹配---

#include "stdafx.h"
#include "opencv2/core/core.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include <opencv2/highgui/highgui.hpp>

#include <ctime>

#include <Windows.h>
#include <iostream>
#include <string>
XYposition myTemplateMatch(cv::Mat &img, cv::Mat &mytemplate)
{
cv::Mat result(img.rows - mytemplate.rows + 1, img.cols - mytemplate.cols + 1, CV_32F);

//***************BREAKS RIGHT HERE****************************
cv::matchTemplate(img, mytemplate, result, CV_TM_SQDIFF_NORMED);
cv::normalize(result, result, 0, 1, cv::NORM_MINMAX, -1, cv::Mat());

double minVal; double maxVal; 
cv::Point minLoc; 
cv::Point maxLoc;
cv::Point matchLoc;

cv::minMaxLoc(result, &minVal, &maxVal, &minLoc, &maxLoc, cv::Mat());
XYposition playerData = {
    maxLoc.x + mytemplate.cols, maxLoc.y + mytemplate.rows
};

rectangle(result, matchLoc, cv::Point(matchLoc.x + mytemplate.cols, matchLoc.y + mytemplate.rows),
    cv::Scalar(0, 0, 255), 4, 8, 0);


cv::namedWindow("cvImage", CV_WINDOW_AUTOSIZE);
cv::imshow("cvImage", result);
cv::waitKey(0);

return playerData;
}

ScreenShot创建

cv::Mat windowToMat(HWND hwnd){

HDC hwindowDC, hwindowCompatibleDC;

int height, width, srcheight, srcwidth;
HBITMAP hbwindow;
cv::Mat src;
BITMAPINFOHEADER  bi;

hwindowDC = GetDC(hwnd);
hwindowCompatibleDC = CreateCompatibleDC(hwindowDC);
SetStretchBltMode(hwindowCompatibleDC, COLORONCOLOR);

RECT windowsize;    // get the height and width of the screen
GetClientRect(hwnd, &windowsize);

srcheight = windowsize.bottom;
srcwidth = windowsize.right;
height = windowsize.bottom / 2;  //change this to whatever size you want to resize to
width = windowsize.right / 2;

src.create(height, width, CV_32F);

// create a bitmap
hbwindow = CreateCompatibleBitmap(hwindowDC, width, height);
bi.biSize = sizeof(BITMAPINFOHEADER);
bi.biWidth = width;
bi.biHeight = -height;  //this is the line that makes it draw upside down or not
bi.biPlanes = 1;
bi.biBitCount = 32;
bi.biCompression = BI_RGB;
bi.biSizeImage = 0;
bi.biXPelsPerMeter = 0;
bi.biYPelsPerMeter = 0;
bi.biClrUsed = 0;
bi.biClrImportant = 0;

// use the previously created device context with the bitmap
SelectObject(hwindowCompatibleDC, hbwindow);
// copy from the window device context to the bitmap device context
StretchBlt(hwindowCompatibleDC, 0, 0, width, height, hwindowDC, 0, 0, srcwidth, srcheight, SRCCOPY); //change SRCCOPY to NOTSRCCOPY for wacky colors !
GetDIBits(hwindowCompatibleDC, hbwindow, 0, height, src.data, (BITMAPINFO *)&bi, DIB_RGB_COLORS);  //copy from hwindowCompatibleDC to hbwindow

// avoid memory leak
DeleteObject(hbwindow); DeleteDC(hwindowCompatibleDC); ReleaseDC(hwnd, hwindowDC);

return src;
}

推荐答案

问题是， Mat 正在使用的图像不同。如果你使用Mat的 .type（）函数，你可以检查传递给函数的参数。使用此表格交叉引用该值

The problem was that the type of Mat images being used was different. If you use the Mat's .type() function you can check the parameters being passed into the function. Cross reference that value with this table

在OpenCV中将类型映射到数字

        C1  C2  C3  C4
CV_8U   0   8   16  24
CV_8S   1   9   17  25
CV_16U  2   10  18  26
CV_16S  3   11  19  27
CV_32S  4   12  20  28
CV_32F  5   13  21  29
CV_64F  6   14  22  30

，您可以更改类型截图创建中的

src.create（height，width，CV_32F）;

到任何值。

这篇关于模板匹配屏幕截图在断言时失败的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！