Question

我在Mac上使用以下代码与OpenCV。以下函数从另一个函数接收图像文件的路径，并且工作正常。但是，cvExtractSURF会抛出一个异常，说明：

OpenCV错误：cvCreateSeq中输入数组（）的大小不正确，文件＆gt; /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarb> alls_ports_graphics_opencv / opencv / work / OpenCV-2.4.1 / modules / core / src / datastructs.cpp，第372行终止调用抛出异常

代码如下：

- (int)extractFromImagePath:(NSString*)pathToFile{
[self.statusText setStringValue:@"image received"];
NSLog(@"Path: %@",pathToFile);
// Path: /Users/loco/Desktop/testimage.png

const char * path = [pathToFile UTF8String];
IplImage* image = cvLoadImage(path, CV_LOAD_IMAGE_GRAYSCALE );
cv::Mat im = cv::imread(path,0);
if(im.data == NULL) 
{
    std::cout<<"Unable to read "<<path<<std::endl;
    return 0;
}    

/* extract the SURF keypoints/descriptors of an image */
// presumes a previously declared IplImage *image
CvSeq *keypoints = NULL;
CvSeq *descriptors = NULL;
CvMemStorage *storage = cvCreateMemStorage(0);
cvExtractSURF(image, NULL, &keypoints, &descriptors, storage, cvSURFParams(0, 600));
// OpenCV Error: Incorrect size of input array () in cvCreateSeq, file /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_graphics_opencv/opencv/work/OpenCV-2.4.1/modules/core/src/datastructs.cpp, line 372
// terminate called throwing an exception


[self.statusText setStringValue:@"writing to files"];

/* build a path to save a file in the documents directoy */
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *docs = [paths objectAtIndex:0];
NSString *xmlpath_kp = [docs stringByAppendingPathComponent:@"keypoints.xml"];
NSString *xmlpath_desc = [docs stringByAppendingPathComponent:@"descriptors.xml"];

/* serialize to xml and save to disc */
cvSave([xmlpath_kp UTF8String], keypoints);
cvSave([xmlpath_desc UTF8String], descriptors);

[self.statusText setStringValue:@"done"];
/* don't forget your cleanup ;) */
cvReleaseImage(&image);
cvClearMemStorage(storage);
return 1;
}

有人知道发生了什么吗？任何帮助将不胜感激！

Answer 1

我测试了部分代码抛出错误。以下代码没有给出任何错误，只需检查一下。

IplImage* image = cvLoadImage("C:\\Koala.jpg",CV_LOAD_IMAGE_GRAYSCALE);
CvSeq* kp_pns;
CvSeq* desct;
CvSURFParams pams;
pams.hessianThreshold=10;
pams.nOctaveLayers=4;
pams.nOctaves=3;
pams.upright = true;
CvMemStorage *storage = cvCreateMemStorage(0);
cvExtractSURF(image,NULL,&kp_pns,&desct,storage,pams,0);

我能够毫无错误地提取冲浪关键点。我希望错误将得到解决。

Answer 2

调整SURF的hessianThreshold; 来自OpenCV他们说;

hessianThreshold 只有粗体大于此值的特征提取。良好的默认值是~300-500（可能取决于平均值局部对比度和图像的清晰度）。用户可以进一步过滤根据他们的粗麻布值和其他特征输出一些特征特性

Answer 3

安德烈卡马耶夫指出，这是2.4.0中的一个错误。 2.4.1。升级确实解决了这个问题。

cvExtractSURF抛出异常，cvCreateSeq中输入数组（）的大小不正确

3 个答案: