在Android Studio 2.2上集成OpenCV4Android SDK
OpenCV官方的教程是基于Eclipse配置开发环境,但是Eclipse已经被Google抛弃了,所以我是写这篇文章的前三天刚刚开始用Android Studio 2.2版本,很多Gradle脚本也不熟悉,只能各种查找。经过一番痛苦的领悟终于把OpenCV4Android集成到我在Android Studio中创建的项目上了,并且写了测试程序。下面说一下如何实现集成步骤,首先是准备工作要做好:
- 下载好Android Studio 2.2版本
- 下载好OpenCV4AndroidSDK - 去OpenCV社区官网即可得到。
- 下载之后解压缩到D:\OpenCV-2.4.11-android-sdk\OpenCV-android-sdk
- apk目录里面放的是OpenCV Manager的安装文件,是不同CPU版本要选择不同apk安装文件,这种方式调用OpenCV比较麻烦。不推荐!
- doc目录里面放的是相关文档与OpenCV的LOGO
- samples里面放的是OpenCV4Android的演示代码,参考价值很大,值得关注
- sdk里面放内容就是我们要重点关注的,集成到Android Studio中的项目上去的东西。
双击打开sdk文件夹就会看到:
准备工作做好之后,首先就是要在Android Studio中创建一个Android项目,创建好之后,选择File->New->Import Module
然后选择到SDK路径下的JAVA
导入之后,你就会看到
就说明成功导入了,然后打开Module Settings
添加依赖之后,就可以在项目中引用OpenCV相关API代码了,如果你此刻运行测试apk程序,它就会提示你安装OpenCV Manager这个东西。对多数开发者来说这不算配置成功,这样自己的APP就无法独立安装,必须依赖OpenCV Manager这个apk文件才可以运行,这个时候就该放大招来解决这个问题,
首先把我们准备阶段看到SDK下面native文件下所有的文件都copy到你创建好的项目libs目录下,然后在gradle中加上如下一段脚本:
task nativeLibsToJar(type: Jar, description: 'create a jar archive of the native libs') { destinationDir file("$buildDir/native-libs") baseName 'native-libs' from fileTree(dir: 'libs', include: '**/*.so') into 'lib/' } tasks.withType(JavaCompile) { compileTask -> compileTask.dependsOn(nativeLibsToJar) }
然后还要加上这句话:
compile fileTree(dir: "$buildDir/native-libs", include: 'native-libs.jar')
最后一步,检查一下gradle文件:
如此配置之后你就再也不需要其它任何配置了,这样既避免了NDK繁琐又不用依赖OpenCV Manager第三方APP,你的APP就可以直接使用OpenCV了。
特别说明:
此配置方式OpenCV加载必须通过静态加载方式,以下为Demo测试程序代码:
package com.example.administrator.helloworld; import android.content.Intent; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.net.Uri; import android.provider.MediaStore; import android.support.annotation.NonNull; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.support.v7.view.ActionMode; import android.util.Log; import android.view.View; import android.widget.Button; import android.widget.ImageView; import android.widget.Toast; import org.opencv.android.BaseLoaderCallback; import org.opencv.android.OpenCVLoader; import org.opencv.android.Utils; import org.opencv.core.Core; import org.opencv.core.CvType; import org.opencv.core.Mat; import org.opencv.core.Size; import org.opencv.imgproc.Imgproc; import java.io.InputStream; import static android.widget.Toast.makeText; public class MainActivity extends AppCompatActivity { private double max_size = 1024; private int PICK_IMAGE_REQUEST = 1; private ImageView myImageView; private Bitmap selectbp; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); staticLoadCVLibraries(); myImageView = (ImageView)findViewById(R.id.imageView); myImageView.setScaleType(ImageView.ScaleType.FIT_CENTER); Button selectImageBtn = (Button)findViewById(R.id.select_btn); selectImageBtn.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { // makeText(MainActivity.this.getApplicationContext(), "start to browser image", Toast.LENGTH_SHORT).show(); selectImage(); } }); Button processBtn = (Button)findViewById(R.id.process_btn); processBtn.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { // makeText(MainActivity.this.getApplicationContext(), "hello, image process", Toast.LENGTH_SHORT).show(); convertGray(); } }); } //OpenCV库静态加载并初始化 private void staticLoadCVLibraries(){ boolean load = OpenCVLoader.initDebug(); if(load) { Log.i("CV", "Open CV Libraries loaded..."); } } private void convertGray() { Mat src = new Mat(); Mat temp = new Mat(); Mat dst = new Mat(); Utils.bitmapToMat(selectbp, src); Imgproc.cvtColor(src, temp, Imgproc.COLOR_BGRA2BGR); Log.i("CV", "image type:" + (temp.type() == CvType.CV_8UC3)); Imgproc.cvtColor(temp, dst, Imgproc.COLOR_BGR2GRAY); Utils.matToBitmap(dst, selectbp); myImageView.setImageBitmap(selectbp); } @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { super.onActivityResult(requestCode, resultCode, data); if(requestCode == PICK_IMAGE_REQUEST && resultCode == RESULT_OK && data != null && data.getData() != null) { Uri uri = data.getData(); try { Log.d("image-tag", "start to decode selected image now..."); InputStream input = getContentResolver().openInputStream(uri); BitmapFactory.Options options = new BitmapFactory.Options(); options.inJustDecodeBounds = true; BitmapFactory.decodeStream(input, null, options); int raw_width = options.outWidth; int raw_height = options.outHeight; int max = Math.max(raw_width, raw_height); int newWidth = raw_width; int newHeight = raw_height; int inSampleSize = 1; if(max > max_size) { newWidth = raw_width / 2; newHeight = raw_height / 2; while((newWidth/inSampleSize) > max_size || (newHeight/inSampleSize) > max_size) { inSampleSize *=2; } } options.inSampleSize = inSampleSize; options.inJustDecodeBounds = false; options.inPreferredConfig = Bitmap.Config.ARGB_8888; selectbp = BitmapFactory.decodeStream(getContentResolver().openInputStream(uri), null, options); myImageView.setImageBitmap(selectbp); } catch (Exception e) { e.printStackTrace(); } } } private void selectImage() { Intent intent = new Intent(); intent.setType("image/*"); intent.setAction(Intent.ACTION_GET_CONTENT); startActivityForResult(Intent.createChooser(intent,"选择图像..."), PICK_IMAGE_REQUEST); } }
选择一张图像加载之后显示:
点击【处理】之后,通过调用OpenCV API实现了灰度转换
特别说明:这种方式调用OpenCV无需NKD以及安装OpenCV Manager。应该是广大Android开发人员最喜欢的一种方式。
免费环境搭建视频查看: