Opencv Library For Android Download

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Opencv

In order to build the aar library file, firstly we need to build opencv files:

Jan 06, 2016  On www.opencv.org there is a link to download the library for Android. Download it, unpack it. If you've followed the post about compiling OpenCV yourself, you already have a directory in your homedirectory somewhere: opencv/ opencv/opencv-3.1/ opencv/build/ now, add the unpacked Android. Open Computer Vision Library. About; Releases; Courses; Resources. Books; Links; Platforms; Releases. OpenCV – 4.1.2.

Preparation

  • Update submodule project: opencv and opencv_contrib

  • Install Android Studio and install necessary components of Android from Android Studio

  • Download Android NDK r10e from: https://developer.android.com/ndk/downloads/older_releases.html

    • Linux: https://dl.google.com/android/repository/android-ndk-r10e-linux-x86_64.zip
    • Mac: https://dl.google.com/android/repository/android-ndk-r10e-darwin-x86_64.zip
    • P.S. Current opencv (3.4.0) only support up to ndk r10.

  • Download Android sdk tools version 25.2.5, overwrite tools folder inside android sdk folder.

    • Linux: https://dl.google.com/android/repository/tools_r25.2.5-linux.zip
    • Mac: https://dl.google.com/android/repository/tools_r25.2.5-macosx.zip
    • P.S. After version 25.5.2, android command is deleted which is used by opencv build script.

  • Install cmake, ninja, ant

    • Ubuntu: sudo apt install cmake ninja-build ant
    • Mac: brew install cmake ninja ant
Download

Build

  • Assume directories are as follows:

    • ndk: ~/android-ndk-r10e
    • sdk: ~/Android/Sdk
      • Default sdk directory:
        • Linux: ~/Android/Sdk
        • Mac: ~/Library/Android/sdk

  • Enter dir: fingerprint-frontend/opencv-library

  • If got error CMake was unable to find a build program corresponding to 'Ninja' on Mac, we need to modify ./opencv/platforms/android/build_sdk.py:

  • run the build script:

Reference

OpenCV4Android, packaged as a .aar for direct use without depending on the stupid OpenCV Manager app.

Building an .aar of OpenCV-3.x.y for yourself

Building OpenCV-3.x.y for Android is actually quite simple, its just not obvious where to get the pieces and the OpenCV docs hard-sell the 'OpenCV Manager' in favour of the better and easier direct integration approach.

Here's the steps I used to create my .aar:

  1. Download and extract the OpenCV4Android bundle
  2. Create a Library Project in Android Studio
  3. Copy the java source files from OpenCV4Android into src/main/java
  4. Drop the OpenCV native libraries into src/main/jniLibs
  5. Run the gradle build
  6. Et voila, .aar file

Using your glorious new .aar

Reference the maven repository you've deployed your .aar to, e.g. mine (which I can't stop you from using ;)) is:

Include the .aar in your build.gradle file:

Bootstrap OpenCV in your Java code:

Opencv 2.4 Download

Optional but recommended: to keep the downloaded APK size to a minimum, build separate APK's per architecture (approx 10MB each vs 42MB for universal) by placing the following inside the 'android' gradle directive of your application's build.gradle:

Opencv Library For Android Download Windows 7

Disclaimer: This project is simply my bundling of OpenCV as an Android Library. I am not otherwise involved in the OpenCV project, and all credit for the wonderful OpenCV library goes to the developers thereof.