Problem with xcode and iOS 12

asked 2018-10-10 06:29:20 -0500

Hello Guys,

I want to use opencv in my iOS app only I have a problem there.

The OpenCV version: 3.4.3

My Class

#ifdef __cplusplus
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdocumentation"

#import <opencv2/opencv.hpp>
#import <opencv2/imgcodecs/ios.h>
#include "ImageDetection.h"

#pragma clang pop

using namespace cv;
using namespace std;

#pragma mark - ImageDetection

@implementation ImageDetection

#pragma mark Public

+ (BOOL)processImage:(UIImage *)source {
    UIImage *tplImg = [UIImage imageNamed:@"item1"];
    cv::Mat tpl;
    cv::Mat gtpl;
    UIImageToMat(tplImg, tpl);
    cv::cvtColor(tpl, gtpl, CV_BGR2GRAY);

    cv::Mat img;
    cv::Mat gimg;
    UIImageToMat(source, img);
    cv::cvtColor(img, gimg, CV_BGR2GRAY);

    cv::Mat res(img.rows-gtpl.rows+1,gtpl.cols-gtpl.cols+1, CV_32FC1);
    cv::matchTemplate(gimg, gtpl, res, CV_TM_CCOEFF_NORMED);
    cv::threshold(res, res, 0.5, 1., CV_THRESH_TOZERO);

    double minval, maxval, threshold = 0.9;
    cv::Point minloc, maxlog;
    cv::minMaxLoc(res, &minval, &maxval, &minloc, &maxlog);

    // If is´s a enought match
    if (maxval >= threshold) {
        return YES;

    return NO;


and xcode say


In file included from /Users/default/Desktop/iOS Projects/Reader/Reader/Frameworks/OpenCV/
In file included from /Users/default/Desktop/iOS Projects/Reader/opencv2.framework/Headers/opencv.hpp:62:
In file included from /Users/default/Desktop/iOS Projects/Reader/opencv2.framework/Headers/dnn.hpp:76:
In file included from /Users/default/Desktop/iOS Projects/Reader/opencv2.framework/Headers/dnn/dnn.hpp:914: 
/Users/default/Desktop/iOS Projects/Reader/opencv2.framework/Headers/dnn/dnn.inl.hpp:280:5: error: use of undeclared identifier 'CV_ErrorNoReturn'
    CV_ErrorNoReturn(Error::StsInternal, "");
1 error generated.
Command Analyze failed with a nonzero exit code

I wonder where the mistake is.

With kind regards CrafterGamer

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Are you using cocoapods?

mister_man gravatar imagemister_man ( 2018-10-10 13:03:43 -0500 )edit

No not use cocoapods. Import this in project folder. An older version working, The new version not working.

CrafterGamer gravatar imageCrafterGamer ( 2018-10-11 02:24:51 -0500 )edit

Have you been able to solve this ? I noticed that although the project does not build, it runs ok.

vladiacobionut gravatar imagevladiacobionut ( 2018-11-08 04:05:50 -0500 )edit