OpenCV/opencv/doc/tutorials/ios/hello/hello.markdown

OpenCV iOS Hello {#tutorial_hello}

@tableofcontents

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| | | | -: | :- | | Original author | Charu Hans | | Compatibility | OpenCV >= 3.0 |

Goal

In this tutorial we will learn how to:

• Link OpenCV framework with Xcode
• How to write simple Hello World application using OpenCV and Xcode.

Linking OpenCV iOS

Follow this step by step guide to link OpenCV to iOS.

-# Create a new XCode project. -# Now we need to link opencv2.framework with Xcode. Select the project Navigator in the left

hand panel and click on project name.

-# Under the TARGETS click on Build Phases. Expand Link Binary With Libraries option. -# Click on Add others and go to directory where opencv2.framework is located and click open -# Now you can start writing your application.

Hello OpenCV iOS Application

Now we will learn how to write a simple Hello World Application in Xcode using OpenCV.

• Link your project with OpenCV as shown in previous section.

• Open the file named NameOfProject-Prefix.pch ( replace NameOfProject with name of your project) and add the following lines of code. @code{.m} #ifdef __cplusplus #import #endif @endcode

• Add the following lines of code to viewDidLoad method in ViewController.m. @code{.m} UIAlertView * alert = [[UIAlertView alloc] initWithTitle:@"Hello!" message:@"Welcome to OpenCV" delegate:self cancelButtonTitle:@"Continue" otherButtonTitles:nil]; [alert show]; @endcode

• You are good to run the project.

Output



Changes for XCode5+ and iOS8+

With the newer XCode and iOS versions you need to watch out for some specific details

• The *.m file in your project should be renamed to *.mm.
• You have to manually include AssetsLibrary.framework into your project, which is not done anymore by default.