Android手机摄像头编程入门1.docx

Android手机摄像头编程入门实例：窈窈照相机，功能很简单，就是点击程序弹出照相预览界面，点击相机按钮完成照相功能，所照相片会存储在手机存储卡根目录。1、创建一个项目 Lesson36_Camera ，主程序文件为 MainActivity.java2、AndroidManifest.xml 中设置屏幕为横屏，并且声明摄像头和存储卡的使用权限，具体代码如下：view sourceprint?01020304050607080910111213141516173、本例中不需要布局文件main.xml，因为本例中的UI组建都是动态添加上去的。4、最后MainActivity.java的代码如下：view sourceprint?001packagebasic.android.lesson36;002003importjava.io.BufferedOutputStream;004importjava.io.File;005importjava.io.FileOutputStream;006importjava.io.IOException;007importjava.util.Calendar;008importjava.util.Locale;009010importandroid.app.Activity;011importandroid.content.Context;012importandroid.graphics.Bitmap;013importandroid.graphics.BitmapFactory;014importandroid.graphics.PixelFormat;015importandroid.hardware.Camera;016importandroid.os.Bundle;017importandroid.text.format.DateFormat;018importandroid.util.Log;019importandroid.view.KeyEvent;020importandroid.view.SurfaceHolder;021importandroid.view.SurfaceView;022importandroid.view.Window;023importandroid.view.WindowManager;024importandroid.widget.FrameLayout;025importandroid.widget.TextView;026importandroid.widget.Toast;027028publicclassMainActivityextendsActivity 029030privateCameraView cv;031/准备一个相机对象032privateCamera mCamera =null;033/准备一个Bitmap对象034privateBitmap mBitmap =null;035036/准备一个保存图片的PictureCallback对象037publicCamera.PictureCallback pictureCallback =newCamera.PictureCallback() 038039publicvoidonPictureTaken(byte data, Camera camera) 040Log.i(yao,onPictureTaken);041Toast.makeText(getApplicationContext(),正在保存, Toast.LENGTH_LONG).show();042/用BitmapFactory.decodeByteArray()方法可以把相机传回的裸数据转换成Bitmap对象043mBitmap = BitmapFactory.decodeByteArray(data,0, data.length);044/接下来的工作就是把Bitmap保存成一个存储卡中的文件045File file =newFile(/sdcard/YY+newDateFormat().format(yyyyMMdd_hhmmss, Calendar.getInstance(Locale.CHINA) +.jpg);046try047file.createNewFile();048BufferedOutputStream os =newBufferedOutputStream(newFileOutputStream(file);049mBpress(Bitmap.CompressFormat.PNG,100, os);050os.flush();051os.close();052Toast.makeText(getApplicationContext(),图片保存完毕，在存储卡的根目录, Toast.LENGTH_LONG).show();053catch(IOException e) 054e.printStackTrace();055056057058;059060/Activity的创建方法061Override062publicvoidonCreate(Bundle savedInstanceState) 063super.onCreate(savedInstanceState);064065/窗口去掉标题066requestWindowFeature(Window.FEATURE_NO_TITLE);067/窗口设置为全屏068getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);069/设置窗口为半透明070getWindow().setFormat(PixelFormat.TRANSLUCENT);071072/提供一个帧布局073FrameLayout fl =newFrameLayout(this);074075/创建一个照相预览用的SurfaceView子类，并放在帧布局的底层076cv =newCameraView(this);077fl.addView(cv);078079/创建一个文本框添加在帧布局中，我们可以看到，文字自动出现在了SurfaceView的前面，由此你可以在预览窗口做出各种特殊效果080TextView tv =newTextView(this);081tv.setText(请按/相机/按钮拍摄);082fl.addView(tv);083084/设置Activity的根内容视图085setContentView(fl);086087088089/相机按键按下的事件处理方法090publicbooleanonKeyDown(intkeyCode, KeyEvent event) 091Log.i(yao,MainActivity.onKeyDown);092if(keyCode = KeyEvent.KEYCODE_CAMERA) 093if(mCamera !=null) 094Log.i(yao,mCamera.takePicture);095/当按下相机按钮时，执行相机对象的takePicture()方法,该方法有三个回调对象做入参，不需要的时候可以设null096mCamera.takePicture(null,null, pictureCallback);097098099returncv.onKeyDown(keyCode, event);100101102/ 照相视图103classCameraViewextendsSurfaceView 104105privateSurfaceHolder holder =null;106107/构造函数108publicCameraView(Context context) 109super(context);110Log.i(yao,CameraView);111112/ 操作surface的holder113holder =this.getHolder();114/ 创建SurfaceHolder.Callback对象115holder.addCallback(newSurfaceHolder.Callback() 116117Override118publicvoidsurfaceDestroyed(SurfaceHolder holder) 119/ 停止预览120mCamera.stopPreview();121/ 释放相机资源并置空122mCamera.release();123mCamera =null;124125126Override127publicvoidsurfaceCreated(SurfaceHolder holder) 128/当预览视图创建的时候开启相机129mCamera = Camera.open();130try131/设置预览132mCamera.setPreviewDisplay(holder);133catch(IOException e) 134/ 释放相机资源并置空135mCamera.release();136mCamera =null;137138139140141/当surface视图数据发生变化时，处理预览信息142Override143publicvoidsurfaceChanged(SurfaceHolder holder,intformat,intwidth,intheight) 144145/获得相机参数对象146Camera.Parameters parameters = mCamera.getParameters();147/设置格式148parameters.setPictureFormat(PixelFormat.JPEG);149/设置预览大小，这里我的测试机是Milsstone所以设置的是854x480150parameters.setPreviewSize(854,480);151/设置自动对焦152parameters.setFocusMode(auto);153/设置图片保存时的分辨率大小154parameters.setPictureSize(2592,1456);155/给相机对象设置刚才设定的参数156mCamera.setParameters(parameters);157/开始预览158mCamera.startPrev