Question

如何在Android中使用OpenCV

Answer 1

在Android中使用OpenCV方法为：
a、OpenCV安装路径"F:\OpenCV-2.3.1-android-bin"下有两个文件夹。将文件夹"OpenCV-2.3.1"拷贝到Eclipse工作空间所在的目录，也就是在你的项目的上一级目录中，然后导入到工作空间中，在Package Explorer中选择项目，单机右键在弹出菜单中选择Properties，然后在弹出的Properties窗口中左侧选择Android，然后点击右下方的Add按钮，选择OpenCV-2.3.1并点击OK,。
b、此时，展开项目树，可以看到新加了一个OpenCV-2.3.1_src目录，如下图，那么就是正确添加了OpenCV Java API，否则就是放置OpenCV-2.3.1的目录路径不正确。
c、然后就可以在Java源文件中导入OpenCV的API包，并且使用OpenCV API了，OpenCV API的包的形式如下：
Org.opencv.(OpenCV模块名).(OpenCV类名)
例如：
Org.opencv.core.Mat

Answer 2

整个项目的结构图： 编写DetectFaceDemo.java,代码如下： [java] view plaincopyprint? package com.njupt.zhb.test; import org.opencv.core.Core; import org.opencv.core.Mat; import org.opencv.core.MatOfRect; import org.opencv.core.Point; import org.opencv.core.Rect; import org.opencv.core.Scalar; import org.opencv.highgui.Highgui; import org.opencv.objdetect.CascadeClassifier; // // Detects faces in an image, draws boxes around them, and writes the results // to "faceDetection.png". // public class DetectFaceDemo { public void run() { System.out.println("\nRunning DetectFaceDemo"); System.out.println(getClass().getResource("lbpcascade_frontalface.xml").getPath()); // Create a face detector from the cascade file in the resources // directory. //CascadeClassifier faceDetector = new CascadeClassifier(getClass().getResource("lbpcascade_frontalface.xml").getPath()); //Mat image = Highgui.imread(getClass().getResource("lena.png").getPath()); //注意：源程序的路径会多打印一个‘/’，因此总是出现如下错误 /* * Detected 0 faces Writing faceDetection.png libpng warning: Image * width is zero in IHDR libpng warning: Image height is zero in IHDR * libpng error: Invalid IHDR data */ //因此，我们将第一个字符去掉 String xmlfilePath=getClass().getResource("lbpcascade_frontalface.xml").getPath().substring(1); CascadeClassifier faceDetector = new CascadeClassifier(xmlfilePath); Mat image = Highgui.imread(getClass().getResource("we.jpg").getPath().substring(1)); // Detect faces in the image. // MatOfRect is a special container class for Rect. MatOfRect faceDetections = new MatOfRect(); faceDetector.detectMultiScale(image, faceDetections); System.out.println(String.format("Detected %s faces", faceDetections.toArray().length)); // Draw a bounding box around each face. for (Rect rect : faceDetections.toArray()) { Core.rectangle(image, new Point(rect.x, rect.y), new Point(rect.x + rect.width, rect.y + rect.height), new Scalar(0, 255, 0)); } // Save the visualized detection. String filename = "faceDetection.png"; System.out.println(String.format("Writing %s", filename)); Highgui.imwrite(filename, image); } } package com.njupt.zhb.test; import org.opencv.core.Core; import org.opencv.core.Mat; import org.opencv.core.MatOfRect; import org.opencv.core.Point; import org.opencv.core.Rect; import org.opencv.core.Scalar; import org.opencv.highgui.Highgui; import org.opencv.objdetect.CascadeClassifier; // // Detects faces in an image, draws boxes around them, and writes the results // to "faceDetection.png". // public class DetectFaceDemo { public void run() { System.out.println("\nRunning DetectFaceDemo"); System.out.println(getClass().getResource("lbpcascade_frontalface.xml").getPath()); // Create a face detector from the cascade file in the resources // directory. //CascadeClassifier faceDetector = new CascadeClassifier(getClass().getResource("lbpcascade_frontalface.xml").getPath()); //Mat image = Highgui.imread(getClass().getResource("lena.png").getPath()); //注意：源程序的路径会多打印一个‘/’，因此总是出现如下错误 /* * Detected 0 faces Writing faceDetection.png libpng warning: Image * width is zero in IHDR libpng warning: Image height is zero in IHDR * libpng error: Invalid IHDR data */ //因此，我们将第一个字符去掉 String xmlfilePath=getClass().getResource("lbpcascade_frontalface.xml").getPath().substring(1); CascadeClassifier faceDetector = new CascadeClassifier(xmlfilePath); Mat image = Highgui.imread(getClass().getResource("we.jpg").getPath().substring(1)); // Detect faces in the image. // MatOfRect is a special container class for Rect. MatOfRect faceDetections = new MatOfRect(); faceDetector.detectMultiScale(image, faceDetections); System.out.println(String.format("Detected %s faces", faceDetections.toArray().length)); // Draw a bounding box around each face. for (Rect rect : faceDetections.toArray()) { Core.rectangle(image, new Point(rect.x, rect.y), new Point(rect.x + rect.width, rect.y + rect.height), new Scalar(0, 255, 0)); } // Save the visualized detection. String filename = "faceDetection.png"; System.out.println(String.format("Writing %s", filename)); Highgui.imwrite(filename, image); } } 3.编写测试类： [java] view plaincopyprint? package com.njupt.zhb.test; public class TestMain { public static void main(String[] args) { System.out.println("Hello, OpenCV"); // Load the native library. System.loadLibrary("opencv_java246"); new DetectFaceDemo().run(); } } //运行结果: //Hello, OpenCV // //Running DetectFaceDemo ///E:/eclipse_Jee/workspace/JavaOpenCV246/bin/com/njupt/zhb/test/lbpcascade_frontalface.xml //Detected 8 faces //Writing faceDetection.png package com.njupt.zhb.test; public class TestMain { public static void main(String[] args) { System.out.println("Hello, OpenCV"); // Load the native library. System.loadLibrary("opencv_java246"); new DetectFaceDemo().run(); } } //运行结果: //Hello, OpenCV // //Running DetectFaceDemo ///E:/eclipse_Jee/workspace/JavaOpenCV246/bin/com/njupt/zhb/test/lbpcascade_frontalface.xml //Detected 8 faces //Writing faceDetection.png