.. _Android_Binary_Package: Using Android binary package with Eclipse ***************************************** This tutorial was tested using Ubuntu 10.04 and Windows 7 SP1 operating systems. Nevertheless, it should also work on any other **OS**\ es supported by Android SDK (including Mac OS X). If you encounter errors after following the steps described here, feel free to contact us via `OpenCV4Android `_ discussion group or OpenCV `Q&A forum `_ and we will try to help you. Quick environment setup for Android development =============================================== If you are making a clean environment installation then you can try `Tegra Android Development Pack `_ (**TADP**) released by **NVIDIA**: It will cover all of the environment set up automatically and you can go to the next step :ref:`Get_the_OpenCV_package_for_Android_development` right after automatic setup. If you are a beginner in Android development then we recommend you to start with TADP. .. note:: *NVIDIA*\ 's Tegra Android Development Pack includes some special features for |Nvidia_Tegra_Platform|_ but it is not just for *Tegra* devices + You need at least *1.6 Gb* free disk space for installation. + TADP will download Android SDK platforms and Android NDK from Google's server, so you need an Internet connection for the installation. + TADP can ask you to flash your development kit at the end of installation process. Just skip this step if you have no |Tegra_Ventana_Development_Kit|_\ . + (``UNIX``) TADP will ask you for a *root* in the middle of installation, so you need to be a member of *sudo* group. .. .. |Nvidia_Tegra_Platform| replace:: *NVIDIA*\ ’s Tegra platform .. _Nvidia_Tegra_Platform: http://developer.nvidia.com/node/19071 .. |Tegra_Ventana_Development_Kit| replace:: Tegra Ventana Development Kit .. _Tegra_Ventana_Development_Kit: http://developer.nvidia.com/tegra-ventana-development-kit .. _Android_Environment_Setup_Lite: Manual environment setup for Android Development ================================================ You need the following tools to be installed: #. **Sun JDK 6** Visit `Java SE Downloads page `_ and download installer for your OS. Here is a detailed :abbr:`JDK (Java Development Kit)` `installation guide `_ for Ubuntu and Mac OS (only JDK sections are applicable for OpenCV) .. note:: OpenJDK is not usable for Android development because Android SDK supports only Sun JDK. If you use Ubuntu, after installation of Sun JDK you should run the following command to set Sun java environment: .. code-block:: bash sudo update-java-alternatives --set java-6-sun #. **Android SDK** Get the latest ``Android SDK`` from http://developer.android.com/sdk/index.html Here is Google's `install guide `_ for SDK. .. note:: If you choose SDK packed into Windows installer, then you should have 32-bit JRE installed. It is not needed for Android development, but installer is x86 application and requires 32-bit Java runtime. .. note:: If you are running x64 version of Ubuntu Linux, then you need ia32 shared libraries for use on amd64 and ia64 systems to be installed. You can install them with the following command: .. code-block:: bash sudo apt-get install ia32-libs For Red Hat based systems the following command might be helpful: .. code-block:: bash sudo yum install libXtst.i386 #. **Android SDK components** You need the following SDK components to be installed: * *Android SDK Tools, revision14* or newer Older revisions should also work, but they are not recommended. * *SDK Platform Android 3.0, API 11* (also known as *android-11*) The minimal platform supported by OpenCV Java API is **Android 2.2** (API 8). This is also the minimum API Level required for the provided samples to run. See the ```` tag in their **AndroidManifest.xml** files. But for successful compilation of some samples the **target** platform should be set to Android 3.0 (API 11) or higher. It will not block them from running on Android 2.2+. .. image:: images/android_sdk_and_avd_manager.png :height: 500px :alt: Android SDK Manager :align: center See `Adding SDK Components `_ for help with installing/updating SDK components. #. **Eclipse IDE** Check the `Android SDK System Requirements `_ document for a list of Eclipse versions that are compatible with the Android SDK. For OpenCV 2.4.x we recommend Eclipse 3.7 (Indigo) or later versions. They work well for OpenCV under both Windows and Linux. If you have no Eclipse installed, you can get it from the `download page `_. #. **ADT plugin for Eclipse** This instruction is copied from `Android Developers site `_. Please, visit `that page `_ if you have any troubles with :abbr:`ADT(Android Development Tools)` plugin installation. Assuming that you have Eclipse IDE installed, as described above, follow these steps to download and install the ADT plugin: #. Start Eclipse, then select :menuselection:`Help --> Install New Software...` #. Click :guilabel:`Add` (in the top-right corner). #. In the :guilabel:`Add Repository` dialog that appears, enter "ADT Plugin" for the Name and the following URL for the Location: https://dl-ssl.google.com/android/eclipse/ #. Click :guilabel:`OK` .. note:: If you have trouble acquiring the plugin, try using "http" in the Location URL, instead of "https" (https is preferred for security reasons). #. In the :guilabel:`Available Software` dialog, select the checkbox next to :guilabel:`Developer Tools` and click :guilabel:`Next`. #. In the next window, you'll see a list of the tools to be downloaded. Click :guilabel:`Next`. #. Read and accept the license agreements, then click :guilabel:`Finish`. .. note:: If you get a security warning saying that the authenticity or validity of the software can't be established, click :guilabel:`OK`. #. When the installation completes, restart Eclipse. .. _Get_the_OpenCV_package_for_Android_development: Get the OpenCV package for Android development ============================================== #. Go to the `OpenCV dowload page on SourceForge `_ and download the latest available version. Currently it is |opencv_android_bin_pack_url|_ #. Create new folder for Android+OpenCV development. For this tutorial I have unpacked OpenCV to the :file:`C:\\Work\\android-opencv\\` directory. .. note:: Better to use a path without spaces in it. Otherwise you will probably have problems with :command:`ndk-build`. #. Unpack the OpenCV package into that dir. You can unpack it using any popular archiver (for example with |seven_zip|_): .. image:: images/android_package_7zip.png :alt: Exploring OpenCV package with 7-Zip :align: center On Unix you can use the following command: .. code-block:: bash unzip ~/Downloads/OpenCV-2.4.2-android-sdk.zip .. |opencv_android_bin_pack| replace:: OpenCV-2.4.2-android-sdk.zip .. _opencv_android_bin_pack_url: http://sourceforge.net/projects/opencvlibrary/files/opencv-android/2.4.2/OpenCV-2.4.2-android-sdk.zip/download .. |opencv_android_bin_pack_url| replace:: |opencv_android_bin_pack| .. |seven_zip| replace:: 7-Zip .. _seven_zip: http://www.7-zip.org/ Open OpenCV library and samples in Eclipse ========================================== #. Start the *Eclipse* and choose your workspace location. I recommend to start familiarizing yourself with OpenCV for Android from a new clean workspace. So I have chosen my OpenCV package directory for the new workspace: .. image:: images/eclipse_1_choose_workspace.png :alt: Choosing C:\Work\android-opencv\ as workspace location :align: center #. Configure your ADT plugin (if needed) .. important:: In most cases the ADT plugin finds Android SDK automatically, but sometimes it fails and shows the following prompt: .. image:: images/eclipse_1a_locate_sdk.png :alt: Locating Android SDK :align: center Select :guilabel:`Use existing SDKs` option, browse for Android SDK folder and click :guilabel:`Finish`. To make sure the SDK folder is set correctly do the following step taken from `Configuring the ADT Plugin `_ document from *Google*: * Select :menuselection:`Window --> Preferences...` to open the Preferences panel (Mac OS X: :menuselection:`Eclipse --> Preferences`): .. image:: images/eclipse_2_window_preferences.png :alt: Select Window > Preferences... :align: center * Select :guilabel:`Android` from the left panel. You may see a dialog asking whether you want to send usage statistics to *Google*. If so, make your choice and click :guilabel:`Proceed`. You cannot continue with this procedure until you click :guilabel:`Proceed`. If the SDK folder isn't set you'll see the following: .. image:: images/eclipse_3_preferences_android.png :alt: Select Android from the left panel :align: center * For the SDK Location in the main panel, click :guilabel:`Browse...` and locate your Android SDK directory. * Click :guilabel:`Apply` button at the bottom right corner of main panel. If the SDK folder is already set correctly you'll see something like this: .. image:: images/eclipse_4_locate_sdk.png :alt: Locate Android SDK :align: center * Click :guilabel:`OK` to close preferences dialog. #. Import OpenCV and samples into workspace. OpenCV library is packed as a ready-for-use `Android Library Project `_. You can simply reference it in your projects. Each sample included into the |opencv_android_bin_pack| is a regular Android project that already references OpenCV library. Follow the steps below to import OpenCV and samples into the workspace: * Right click on the :guilabel:`Package Explorer` window and choose :guilabel:`Import...` option from the context menu: .. image:: images/eclipse_5_import_command.png :alt: Select Import... from context menu :align: center * In the main panel select :menuselection:`General --> Existing Projects into Workspace` and press :guilabel:`Next` button: .. image:: images/eclipse_6_import_existing_projects.png :alt: General > Existing Projects into Workspace :align: center * For the :guilabel:`Select root directory` in the main panel locate your OpenCV package folder. (If you have created workspace in the package directory, then just click :guilabel:`Browse...` button and instantly close directory choosing dialog with :guilabel:`OK` button!) Eclipse should automatically locate OpenCV library and samples: .. image:: images/eclipse_7_select_projects.png :alt: Locate OpenCV library and samples :align: center * Click :guilabel:`Finish` button to complete the import operation. After clicking :guilabel:`Finish` button Eclipse will load all selected projects into workspace. And... will indicate numerous errors: .. image:: images/eclipse_8_false_alarm.png :alt: Confusing Eclipse screen with numerous errors :align: center However **all these errors are only false-alarms**! To help Eclipse to understand that there are no any errors choose OpenCV library in :guilabel:`Package Explorer` (left mouse click) and press :kbd:`F5` button on your keyboard. Then choose any sample (except first samples in *Tutorial Base* and *Tutorial Advanced*) and also press :kbd:`F5`. In some cases these errors disappear after :menuselection:`Project --> Clean... --> Clean all --> OK`. Sometimes more advanced manipulations are needed: * The provided projects are configured for `android-11` target that can be missing platform in your Android SDK. After right click on any project select :guilabel:`Properties` and then :guilabel:`Android` on the left pane. Click some target with `API Level` 11 or higher: .. image:: images/eclipse_8a_target.png :alt: Updating target :align: center After this manipulation Eclipse will rebuild your workspace and error icons will disappear one after another: .. image:: images/eclipse_9_errors_dissapearing.png :alt: After small help Eclipse removes error icons! :align: center Once Eclipse completes build you will have the clean workspace without any build errors: .. image:: images/eclipse_10_crystal_clean.png :alt: OpenCV package imported into Eclipse :align: center Running OpenCV Samples ====================== At this point you should be able to build and run all samples except the last two (Tutorial 3 and 4). These samples include native code and require Android NDK to build working applications, see the next tutorial :ref:`Android_Binary_Package_with_NDK` to learn how to compile them. Also I want to note that only ``Tutorial 0 - Android Camera`` and ``Tutorial 1 - Add OpenCV`` samples are able to run on Emulator from the Android SDK. Other samples are using OpenCV Native Camera which does not work with emulator. .. note:: Latest *Android SDK tools, revision 19* can run ARM v7a OS images but *Google* provides such image for Android 4.x only. Well, running samples from Eclipse is very simple: * Connect your device with :command:`adb` tool from Android SDK or create Emulator with camera support. * See `Managing Virtual Devices `_ document for help with Android Emulator. * See `Using Hardware Devices `_ for help with real devices (not emulators). * Select project you want to start in :guilabel:`Package Explorer` and just press :kbd:`Ctrl + F11` or select option :menuselection:`Run --> Run` from the main menu, or click :guilabel:`Run` button on the toolbar. .. note:: Android Emulator can take several minutes to start. So, please, be patient. * On the first run Eclipse will ask you about the running mode for your application: .. image:: images/eclipse_11_run_as.png :alt: Run sample as Android Application :align: center * Select the :guilabel:`Android Application` option and click :guilabel:`OK` button. Eclipse will install and run the sample. Here is ``Tutorial 1 - Add OpenCV`` sample detecting edges using Canny algorithm from OpenCV: .. image:: images/emulator_canny.png :height: 600px :alt: Tutorial 1 Basic - 1. Add OpenCV - running Canny :align: center How to use OpenCV library project in your application ===================================================== In this section we will explain how to make some existing application to use OpenCV. Starting from 2.4.2 release on Android so-called "OpenCV Manager" is used for providing applications with the best version of OpenCV. You can get more information here: :ref:`Android_OpenCV_Manager`. Application development with async initialization ------------------------------------------------- Using async initialization is a preferred way for application development. It uses OpenCV Manager Android service to get OpenCV libraries. #. Add OpenCV library project to your workspace. Go to :guilabel:`File –> Import –> Existing project in your workspace`, push Browse button and select OpenCV SDK path. .. image:: images/eclipse_opencv_dependency0.png :alt: Add dependency from OpenCV library :align: center #. In application project add reference to OpenCV Java SDK in :guilabel:`Project –> Properties –> Android –> Library –> Add` select ``OpenCV Library - 2.4.2``; .. image:: images/eclipse_opencv_dependency1.png :alt: Add dependency from OpenCV library :align: center If you want to use OpenCV Manager-based approach you need to install packages with the Service and OpenCV package for you platform. You can do it using Google Play service or manually with adb tool: .. code-block:: sh :linenos: adb install ./org.opencv.engine.apk adb install ./org.opencv.lib_v24_.apk There is a very base code snippet for Async init. It shows only basis principles of library Initiation. See the "15-puzzle" OpenCV sample for details. .. code-block:: java :linenos: public class MyActivity extends Activity implements HelperCallbackInterface { private BaseLoaderCallback mOpenCVCallBack = new BaseLoaderCallback(this) { @Override public void onManagerConnected(int status) { switch (status) { case LoaderCallbackInterface.SUCCESS: { Log.i(TAG, "OpenCV loaded successfully"); // Create and set View mView = new puzzle15View(mAppContext); setContentView(mView); } break; default: { super.onManagerConnected(status); } break; } } }; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { Log.i(TAG, "onCreate"); super.onCreate(savedInstanceState); Log.i(TAG, "Trying to load OpenCV library"); if (!OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION_2_4_2, this, mOpenCVCallBack)) { Log.e(TAG, "Cannot connect to OpenCV Manager"); } } // ... } It this case application works with OpenCV Manager in asynchronous fashion. ``OnManagerConnected`` callback will be called in UI thread, when initialization finishes. Please note, that it is not allowed to use OpenCV calls or load OpenCV-dependent native libs before invoking this callback. Load your own native libraries after OpenCV initialization. Application development with static initialization -------------------------------------------------- According to this approach all OpenCV binaries are linked and put to your application package. It is designed mostly for development purposes. This way is deprecated for the production code, release package should communicate with OpenCV Manager, use the async initialization described above. #. Add OpenCV library project to your workspace. Go to :guilabel:`File –> Import –> Existing project in your workspace`, push :guilabel:`Browse` button and select OpenCV SDK path. .. image:: images/eclipse_opencv_dependency0.png :alt: Add dependency from OpenCV library :align: center #. In application project add reference to OpenCV Java SDK in :guilabel:`Project –> Properties –> Android –> Library –> Add` select ``OpenCV Library - 2.4.2``; .. image:: images/eclipse_opencv_dependency1.png :alt: Add dependency from OpenCV library :align: center #. Copy native libs to your project directory to folder :file:`libs/target_arch/`. After adding depedency from OpenCV library project, Eclipse will automatically copy all needed libraries to the application package. To use OpenCV functionality you need to add OpenCV library initialization code before using any OpenCV specific code, for example, to the static section of ``Activity`` class. .. code-block:: java :linenos: static { if (!OpenCVLoader.initDebug()) { // Report initialization error } } If you application includes other OpenCV-dependent native libraries you need to init OpenCV before them. .. code-block:: java :linenos: static { if (OpenCVLoader.initDebug()) { System.loadLibrary("my_super_lib1"); System.loadLibrary("my_super_lib2"); } else { // Report initialization error } } Whats next? =========== Read the :ref:`Android_Binary_Package_with_NDK` tutorial to learn how to add native OpenCV code to your Android project.