I am trying to use the OpenCV library in my IOS application. I have installed it using pods and the current version is 2.4.13. Inside the PrefixHeader.pch file, I have included
#ifndef _cplusplus
#import <opencv2/opencv.hpp>
#endif
In my ViewController.m file, when I add the line #import "opencv2/highgui/ios.h", I get the build error
Parse Issue. Expected ')' ios.h.
This ios.h file is included in the library so I have not modified it and its contents:
#include "opencv2/core/core.hpp"
#import "opencv2/highgui/cap_ios.h"
UIImage* MatToUIImage(const cv::Mat& image);
void UIImageToMat(const UIImage* image,
cv::Mat& m, bool alphaExist = false);
According the documentation you need to change the *.m file to *.mm for newer XCode and IOS versions. Try renaming ViewController.m to ViewController.mm and see if that works.
Related
I want to use CUDA/GPU in OpenCV in Visual Studio. For example, cuda::GpuMat. I successfully build OpenCV with the extra modules with CUDA enabled
I tried the following code
#include <string>
#include <opencv2/core/core.hpp>
#include <opencv2/imgcodecs.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/photo/cuda.hpp>
#include <opencv2/photo.hpp>
using namespace std;
using namespace cv;
int main(){
string imageName("input.bmp");
//CPU version
Mat image = imread(imageName.c_str(), IMREAD_GRAYSCALE);
//CUDA version
cuda::GpuMat imageGPU;
cuda::GpuMat downloadGPU;
Mat buff;
imageGPU.upload(image);
downloadGPU.download(buff);
imwrite("gpu.bmp", buff);
return 0;
}
But I get an unhandled exception error.
I originally downloaded OpenCV in C:\Users\me\Downloads\opencv
I then downloaded and installed the latest OpenCV extra modules with CUDA on in
In Property Pages->C/C++->General->Additional Include Directories, I have:
C:\Users\me\Downloads\opencv\build\include\opencv
C:\Users\me\Downloads\opencv\build\include\opencv2
C:\Users\me\Downloads\opencv\build\include\
In Property Pages->Linker->General->Additional Library Directories, I have:
C:\Users\me\Downloads\opencv\build\x64\vc15\lib
and in Property Pages->Linker->Input->Additional Dependencies, I have:
opencv_world343d.lib
opencv_world343.lib
what else am I supposed to include so I can get GpuMat to work properly?
Most of the cases, yes, but you need to know which library you need to add, it may be cufft.lib, cublas.lib, cudnn.lib, etc. It depends of the function you use inside your code.
Opencv includes a cmake include file that would set all of this up for you if you use cmake to build you VS test project. This file will be in the root of the opencv install directory, i.e. after building opencv running cmake --install or the equivalent in VS. The file is OpenCVConfig.cmake, and it would be included in the CMakeLists.txt file for your project. Then you would call FindPackage(OpenCV), which would locate the OpenCV install, setup a few variables, which you would then use to link against your app.
I can post a sample CMakeList.txt file if you feel that would help.
I've built opencv2.framework using OpenCV 3.4 and opencv_contrib in order to use the aruco library. I'm importing this framework into Xcode and I am able to import and use standard OpenCV modules with no compile errors.
I can #import <aruco/aruco.h> with no compile errors. However, as soon as I try to use any classes from aruco I get a compile error. In this case:
Undefined symbols for aruco::MarkerDetector::~MarkerDetector()
#import <opencv2/opencv.hpp>
#import <opencv2/core.hpp>
#import <opencv2/imgcodecs/ios.h>
#import <opencv2/imgproc/imgproc.hpp>
#import <aruco/aruco.h>
-(void)doSomething() {
//anything in cv:: lib is fine, no compile errors
cv::Mat mat(3,3,CV_32);
//but as soon as I try to use aruco I get compile error
aruco::MarkerDetector detector;
}
I got this working. If I include, vs import aruco - #include "opencv/aruco.hpp" I can then use aruco cv::aruco::detectMarkers(....).
For some reason when I import aruco, the code completion doesn't seem to accurately reflect the API and that was causing additional confusion.
I'm trying to play a RTSP stream in Unity 5.
For that I found a RTSP-plugin for Unity on Github that I want to try, but unfortunatelly it comes with no Readme or installation guide whatsoever.
So far I found out that I'm dealing with a C++ Visual Studio project that needs to be compiled into a DLL in order to add it to Unity. But when I try to build the project I get the following Error for the header file "ffmpegenv.h":
Error C1083 Cannot open include file: 'libavutil\opt.h': No such file or directory - (Screenshot)
Here's the code from the header file
#pragma once
//=============================
// Includes
//-----------------------------
// FFMPEG is writen in C so we need to use extern "C"
//-----------------------------
extern "C" {
//#define INT64_C(x) (x ## LL)
//#define UINT64_C(x) (x ## ULL)
#include <libavutil\opt.h>
#include <libavutil/mathematics.h>
#include <libavformat/avformat.h>
#include <libswscale/swscale.h>
#include <libswresample/swresample.h>
#include <libavutil/imgutils.h>
#include <libavcodec/avcodec.h>
}
I'm aware that the header includes source code from the FFmpeg libraries which doesn't come with the plugin I'm trying to compile. So I downloaded the FFmpeg source code from their GitHub page and copied all the code files (with its original folder structure) inside the plugin's project folder.
However when I then try to compile the plugin, it still doesn't find the #includes an shows the same error as mentioned above.
How I can I get the plugin to compile? What am I missing?
Thanks in advance
P.S.: I'm using Visual Studio Community 2017 with C++ support and Win 10 SDK as well as Win 8.1 SDK.
First, I am new to C++ and dlib but I have successfully built the examples and started working on my own project. Things have been progressing smoothly until I try to save a jpeg. Attempting to compile code using dlib::save_jpeg throws a linker error and I cannot track down the solution. I have attempted to add #define DLIB_JPEG_SUPPORT above and below my #includes but no luck. I am using XCode and used cmake -G "Xcode" .. when I compiled the examples. Relevant code below. Since I am on a Mac, I have added header and library search paths for X11 (for dlib gui), OpenCV, and DLIB. I have libjpeg.dylib and linked that to my project with and without #define DLIB_JPEG_SUPPORT in main.cpp. Is there some other build setting I need to specify? Thank you in advance for your help.
Finally, I have seen other questions and pages about dlib and libjpeg issues but no luck yet. And yes I have source.cpp included in the project.
// the standard stuff
#include <string>
#include <iostream>
#include <unistd.h>
// opencv mat object
#include <opencv2/opencv.hpp>
// dlib>
#include <dlib/opencv.h>
#include <dlib/image_io.h>
#include <dlib/gui_widgets.h>
#include <dlib/image_transforms.h>
int main(int argc, const char * argv[]) {
// retrieving images from a TCP connection
// decode data stream
img = cv::imdecode(rawImage, CV_LOAD_IMAGE_COLOR);
// perform image processing
dlib::cv_image<dlib::bgr_pixel> d_image(img);
// finally save the result to jpg
std::string fname = argv[1] + std::to_string(image_id) + ".jpg";
dlib::save_jpeg(d_image, fname); // <- line that won't compile
return 0;
}
After quit a bit of struggling and side-by-side comparisons I finally found the issue. In XCode go to to Build Settings and modify Other Linker Flags, Run Search Paths, and Other C++ Flags to match the compiled and working face_ex example. I wholesale copied all of those flags and included a missing libjpeg.dylib and was able to get things running. It should look something like this for the C++ flags . Hope this helps the next person.
Dear StackOverFlow experts,
I have searched and searched for a solution to this problem but have not found an answer. I have found people with similar questions but not an answer. I humbly ask for your forgiveness if I have overlooked a solution. With this I ask you to please consider my submission.
I have a simple test code for OpenCV 2.4.11 in Visual Studio 2010 x64
#include <opencv\cv.h>
#include <opencv\highgui.h>
#include <opencv2\opencv.hpp>
#include <opencv2\core\types_c.h>
using namespace cv;
int main(){
IplImage* img=cvLoadImage("C:\\Users\\Russ\\Pictures\\3-7-15\\_DSC8489.jpg"); //change the name
cvNamedWindow("Example1",CV_WINDOW_NORMAL );
cvShowImage("Example1",img);
cvWaitKey(0);
cvReleaseImage(&img);
cvDestroyWindow( "Example1");
return 0;
}
When I Build this I get an error
C:\opencv\build\include\opencv2/core/types_c.h(55): fatal error C1083: Cannot open include file: 'assert.h': No such file or directory
All of the opencv includes are included in my properties path as are my libraries for OpenCV. When I open the types_c.h file I see the following
/*M///////////////////////////////////////////////////////////////////////////////////////
//
// IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
//
// By downloading, copying, installing or using the software you agree to this license.
// If you do not agree to this license, do not download, install,
// copy or use the software.
//
//
// License Agreement
// For Open Source Computer Vision Library
//
//M*/
#ifndef __OPENCV_CORE_TYPES_H__
#define __OPENCV_CORE_TYPES_H_
#if !defined _CRT_SECURE_NO_DEPRECATE && defined _MSC_VER
# if _MSC_VER > 1300
# define _CRT_SECURE_NO_DEPRECATE /* to avoid multiple Visual Studio 2005 warnings */
# endif
#endif
#ifndef SKIP_INCLUDES
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include <float.h>
#if !defined _MSC_VER && !defined __BORLANDC__
# include <stdint.h>
#endif
#...
Since assert.h is used for debugging, I decided to comment out the assert.h line. When I Build the code again I got this error.
C:\opencv\build\include\opencv2/core/types_c.h(56): fatal error C1083: Cannot open include file: 'stdlib.h': No such file or directory
Clearly something is not set properly for Visual Studio 2010 as it can not find these libraries. Can someone tell how to fix this problem in Visual Studio 2010 x64. Thanks for your help.
For your case, you only need to include opencv2/opencv.hpp to make it work.
Also, since you're using C++, it's strongly recommended to use OpenCV's C++ API over deprecated C API. The code will be like:
#include <opencv2/opencv.hpp>
int main()
{
cv::Mat img = cv::imread("C:\\Users\\Russ\\Pictures\\3-7-15\\_DSC8489.jpg");
cv::namedWindow("Example1", CV_WINDOW_NORMAL);
cv::imshow("Example1", img);
cv::waitKey(0);
cv::destroyWindow("Example1");
return 0;
}
Updated:
If you still encounter with problems, you should follow this post to setup OpenCV correctly with VS.