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更新:
我发现Link使用OpenCV找出方形.我可以修改它以找到矩形形状吗?有人可以指导我吗?
更新的最新消息:
我终于得到了代码,下面是它.
- (cv::Mat)cvMatWithImage:(UIImage *)image { CGColorSpaceRef colorSpace = CGImageGetColorSpace(image.CGImagE); CGFloat cols = image.size.width; CGFloat rows = image.size.height; cv::Mat cvMat(rows,cols,CV_8UC4); // 8 bits per component,4 chAnnels CGContextRef contextRef = CGBitmapContextCreate(cvMat.data,// Pointer to backing data cols,// Width of bitmap rows,// Height of bitmap 8,// Bits per component cvMat.step[0],// Bytes per row colorSpace,// Colorspace kCGImageAlphaNoneskipLast | kCGBitmapByteOrderDefault); // Bitmap info flags CGContextDrawImage(contextRef,CGRectMake(0,rows),image.CGImagE); CGContextRelease(contextRef); return cvMat; } -(UIImage *)UIImageFromCVMat:(cv::Mat)cvMat { NSData *data = [NSData dataWithBytes:cvMat.data length:cvMat.elemSize()*cvMat.@R_913_10586@l()]; CGColorSpaceRef colorSpace; if ( cvMat.elemSize() == 1 ) { colorSpace = CGColorSpaceCreateDeviceGray(); } else { colorSpace = CGColorSpaceCreateDeviceRGB(); } //CFDataRef data; CGDataProviderRef provider = CGDataProviderCreateWithCFData( (CFDataRef) data ); // It SHOULD BE (__bridge CFDataRef)data CGImageRef imageRef = CGImageCreate( cvMat.cols,cvMat.rows,8,8 * cvMat.elemSize(),cvMat.step[0],colorSpace,kCGImageAlphaNone|kCGBitmapByteOrderDefault,provider,NULL,false,kCGRenderingIntentDefault ); UIImage *finalImage = [UIImage imageWithCGImage:imageRef]; CGImageRelease( imageRef ); CGDataProviderRelease( provider ); CGColorSpaceRelease( colorSpace ); return finalImage; } -(void)forOpenCV { imageView = [UIImage imagenamed:@"myimage.jpg"]; if( imageView != nil ) { cv::Mat tempMat = [imageView CVMat]; cv::Mat greymat = [self cvMatWithImage:imageView]; cv::vector<cv::vector<cv::Point> > squares; cv::Mat img= [self debugSquares: squares: greymat]; imageView = [self UIImageFromCVMat: img]; self.imageView.image = imageView; } } double angle( cv::Point pt1,cv::Point pt2,cv::Point pt0 ) { double dx1 = pt1.x - pt0.x; double dy1 = pt1.y - pt0.y; double dx2 = pt2.x - pt0.x; double dy2 = pt2.y - pt0.y; return (dx1*dx2 + dy1*dy2)/sqrt((dx1*dx1 + dy1*dy1)*(dx2*dx2 + dy2*dy2) + 1e-10); } - (cv::Mat) debugSquares: (std::vector<std::vector<cv::Point> >) squares : (cv::Mat &)image { NSLog(@"%lu",squares.size()); // blur will enhance edge detection //cv::Mat blurred(imagE); cv::Mat blurred = image.clone(); medianBlur(image,blurred,9); cv::Mat gray0(image.size(),CV_8U),gray; cv::vector<cv::vector<cv::Point> > contours; // find squares in every color plane of the image for (int c = 0; c < 3; c++) { int ch[] = {C,0}; mixChAnnels(&image,1,&gray0,ch,1); // try several threshold levels const int threshold_level = 2; for (int l = 0; l < threshold_level; L++) { // Use CAnny instead of zero threshold level! // CAnny Helps to catch squares with gradient shading if (l == 0) { CAnny(gray0,gray,10,20,3); // // Dilate Helps to remove potential holes between edge segments dilate(gray,cv::Mat(),cv::Point(-1,-1)); } else { gray = gray0 >= (l+1) * 255 / threshold_level; } // Find contours and store them in a list findContours(gray,contours,CV_RETR_LIST,CV_CHAIN_APPROX_SIMPLE); // Test contours cv::vector<cv::Point> approx; for (size_t i = 0; i < contours.size(); i++) { // approximate contour with accuracy proportional // to the contour perimeter approxPolyDP(cv::Mat(contours[i]),approx,arcLength(cv::Mat(contours[i]),truE)*0.02,truE); // Note: absolute value of an area is used because // area may be positive or negative - in accordance with the // contour orientation if (approx.size() == 4 && fabs(contourArea(cv::Mat(approX))) > 1000 && isContourConvex(cv::Mat(approX))) { double maxCosine = 0; for (int j = 2; j < 5; j++) { double cosine = fabs(angle(approx[j%4],approx[j-2],approx[j-1])); maxCosine = MAX(maxCosine,cosinE); } if (maxCosine < 0.3) squares.push_BACk(approX); } } } } NSLog(@"squares.size(): %lu",squares.size()); for( size_t i = 0; i < squares.size(); i++ ) { cv::rect rectangle = boundingRect(cv::Mat(squares[i])); NSLog(@"rectangle.x: %d",rectangle.X); NSLog(@"rectangle.y: %d",rectangle.y); if(i==squares.size()-1)////DetecTing Rectangle here { const cv::Point* p = &squares[i][0]; int n = (int)squares[i].size(); NSLog(@"%d",n); line(image,cv::Point(507,418),cv::Point(507+1776,418+1372),cv::Scalar(255,0),2,8); polylines(image,&p,&n,true,255,5,CV_AA); int fx1=rectangle.x; NSLog(@"X: %d",fx1); int fy1=rectangle.y; NSLog(@"Y: %d",fy1); int fx2=rectangle.x+rectangle.width; NSLog(@"Width: %d",fx2); int fy2=rectangle.y+rectangle.height; NSLog(@"Height: %d",fy2); line(image,cv::Point(fx1,fy1),cv::Point(fx2,fy2),cv::Scalar(0,255),8); } } return image; }
谢谢.
我不得不使用raise another question on stackoverflow来处理我糟糕的c知识 – 但是我已经找到了我们需要的所有东西,以使用objective.cpp示例代码作为示例干净地与Objective-c代码进行交互.目的是保持原始c代码尽可能保持原始状态,并将openCV的大部分工作保留在纯c文件中以实现(im)可移植性.
我已将原来的答案留在原处,因为这似乎超出了编辑范围. The complete demo project is on github
CVViewController.h / CVViewController.m
>纯Objective-C
>通过WRAPPER与openCV c代码通信……它既不知道也不关心c正在处理包装器后面的这些方法调用.
CVWrapper.h / CVWrapper.mm
>目标-C
做得尽可能少,真的只有两件事……
>调用UIImage objC类别以转换为UIImage和来自UIImage<> CV ::垫
>介于CVViewController的Obj-C方法和CVSquares c(类)函数调用之间
>纯C
> CVSquares.cpp在类定义中声明公共函数(在本例中为一个静态函数).
这取代了原始文件中main {}的工作.
>我们尽量保持CVSquares.cpp尽可能接近C原件以便于移植.
CVViewController.m
//remove 'magic numbers' from original C++ source so we can manipulate them from Obj-C #define TOLERANCE 0.01 #define THRESHOLD 50 #define LEVELS 9 UIImage* image = [CVSquaresWrapper detectedSquaresInImage:self.image tolerance:TOLERANCE threshold:THRESHOLD levels:LEVELS];
CVSquaresWrapper.h
// CVSquaresWrapper.h #import <Foundation/Foundation.h> @interface CVSquaresWrapper : NSObject + (UIImage*) detectedSquaresInImage:(UIImage*)image tolerance:(CGFloat)tolerance threshold:(NSInteger)threshold levels:(NSInteger)levels; @end
CVSquaresWrapper.mm
// CVSquaresWrapper.mm // wrapper that talks to c++ and to Obj-C classes #import "CVSquaresWrapper.h" #import "CVSquares.h" #import "UIImage+OpenCV.h" @implementation CVSquaresWrapper + (UIImage*) detectedSquaresInImage:(UIImage*) image tolerance:(CGFloat)tolerance threshold:(NSInteger)threshold levels:(NSInteger)levels { UIImage* result = nil; //convert from UIImage to cv::Mat openCV image format //this is a category on UIImage cv::Mat matImage = [image CVMat]; //call the c++ class static member function //we want this function signature to exactly //mirror the form of the calling method matImage = CVSquares::detectedSquaresInImage (matImage,tolerance,threshold,levels); //convert BACk from cv::Mat openCV image format //to UIImage image format (category on UIImagE) result = [UIImage imageFromCVMat:matImage]; return result; } @end
CVSquares.h
// CVSquares.h #ifndef __OpenCVClient__CVSquares__ #define __OpenCVClient__CVSquares__ //class deFinition //in this example we do not need a class //as we have no instance variables and just one static function. //We Could instead just declare the function but this form seems clearer class CVSquares { public: static cv::Mat detectedSquaresInImage (cv::Mat image,float tol,int threshold,int levels); }; #endif /* defined(__OpenCVClient__CVSquares__) */
CVSquares.cpp
// CVSquares.cpp #include "CVSquares.h" using namespace std; using namespace cv; static int thresh = 50,N = 11; static float tolerance = 0.01; //declarations added so that we can move our //public function to the top of the file static void findSquares( const Mat& image,vector<vector<Point> >& squares ); static void drawSquares( Mat& image,vector<vector<Point> >& squares ); //this public function performs the role of //main{} in the original file (main{} is deleted) cv::Mat CVSquares::detectedSquaresInImage (cv::Mat image,int levels) { vector<vector<Point> > squares; if( image.empty() ) { cout << "Couldn't load " << endl; } tolerance = tol; thresh = threshold; N = levels; findSquares(image,squares); drawSquares(image,squares); return image; } // the rest of this file is identical to the original squares.cpp except: // main{} is removed // this line is removed from drawSquares: // imshow(wndname,imagE); // (Obj-C will do the drawing)
UIImage OpenCV.h
UIImage类是一个objC文件,包含在UIImage和cv :: Mat图像格式之间转换的代码.这是你移动你的两个方法的地方 – (UIImage *)UIImageFromCVMat:(cv :: Mat)cvMat和 – (cv :: Mat)cvMatWithImage:(UIImage *)图像
//UIImage+OpenCV.h #import <UIKit/UIKit.h> @interface UIImage (UIImage_OpenCV) //cv::Mat to UIImage + (UIImage *)imageFromCVMat:(cv::Mat&)cvMat; //UIImage to cv::Mat - (cv::Mat)CVMat; @end
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