Android CameraManager类详解
本文实例为大家分享了AndroidCameraManager类的具体代码，供大家参考，具体内容如下
先看代码：
privateSurfaceViewmSurfaceView;
privateSurfaceHoldermSurfaceHolder;
privateCameraManagercameraManager;
cameraManager=newCameraManager(this);
mSurfaceView=(SurfaceView)findViewById(R.id.java_surface_view);
mSurfaceHolder=mSurfaceView.getHolder();
//mSurfaceView不需要自己的缓冲区
mSurfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
//mSurfaceView添加回调
mSurfaceHolder.addCallback(newSurfaceHolder.Callback(){
@Override
publicvoidsurfaceCreated(SurfaceHolderholder){//SurfaceView创建
try{
cameraManager.openDriver(mSurfaceHolder);
cameraManager.startPreview();
}catch(IOExceptione){
e.printStackTrace();
}
}
@Override
publicvoidsurfaceChanged(SurfaceHolderholder,intformat,intwidth,intheight){
}
@Override
publicvoidsurfaceDestroyed(SurfaceHolderholder){//SurfaceView销毁
holder.removeCallback(this);//CameraisbeingusedafterCamera.release()wascalled
cameraManager.stopPreview();
cameraManager.closeDriver();
}
});
自定义一个CameraManager类，在关闭当前页面，释放camera资源时偶尔报错
CameraisbeingusedafterCamera.release()wascalled
第一次，加了一句holder.removeCallback(this);运行发现还是时不时出现报错。
第二次在释放camera前加 camera.setPreviewCallback(null);问题解决。
/**
*关闭预览
*/
publicsynchronizedvoidstopPreview(){
Log.e(TAG,"stopPreview");
if(autoFocusManager!=null){
autoFocusManager.stop();
autoFocusManager=null;
}
if(camera!=null&&previewing){
camera.stopPreview();
camera.setPreviewCallback(null);//CameraisbeingusedafterCamera.release()wascalled
previewing=false;
}
}
/**
*关闭camera
*/
publicsynchronizedvoidcloseDriver(){
Log.e(TAG,"closeDriver");
if(camera!=null){
camera.release();
camera=null;
}
}
附：CameraManager类：
packagecom.lemoncome.facedetection;
importandroid.content.Context;
importandroid.graphics.Bitmap;
importandroid.graphics.BitmapFactory;
importandroid.graphics.ImageFormat;
importandroid.graphics.Matrix;
importandroid.hardware.Camera;
importandroid.util.Log;
importandroid.view.Display;
importandroid.view.Surface;
importandroid.view.SurfaceHolder;
importandroid.view.WindowManager;
importjava.io.IOException;
importjava.util.List;
/**
*User:lizhangqu(513163535@qq.com)
*Date:2015-09-05
*Time:10:56
*/
publicclassCameraManagerimplementsCamera.PreviewCallback{
privatestaticfinalStringTAG=CameraManager.class.getName();
privateCameracamera;
privateCamera.Parametersparameters;
privateAutoFocusManagerautoFocusManager;
privateintrequestedCameraId=-1;
privateContextmContext;
privatebooleaninitialized;
privatebooleanpreviewing;
/**
*打开摄像头
*
*@paramcameraId摄像头id
*@returnCamera
*/
publicCameraopen(intcameraId){
intnumCameras=Camera.getNumberOfCameras();
if(numCameras==0){
Log.e(TAG,"Nocameras!");
returnnull;
}
booleanexplicitRequest=cameraId>=0;
if(!explicitRequest){
//Selectacameraifnoexplicitcamerarequested
intindex=0;
while(indexpreviewSizes=parameters.getSupportedPreviewSizes();
intw=800;
inth=600;
for(Camera.Sizesize:previewSizes){
Log.e("TAG","previewSizeswidth:"+size.width);
Log.e("TAG","previewSizesheight:"+size.height);
if(size.width-w<=100&size.width>=w){
w=size.width;
h=size.height;
break;
}
}
parameters.setPreviewSize(w,h);
parameters.setPictureFormat(ImageFormat.JPEG);
parameters.setJpegQuality(100);
parameters.setPictureSize(800,600);
theCamera.setParameters(parameters);
}
}
/**
*camera是否打开
*
*@returncamera是否打开
*/
publicsynchronizedbooleanisOpen(){
returncamera!=null;
}
/**
*关闭camera
*/
publicsynchronizedvoidcloseDriver(){
Log.e(TAG,"closeDriver");
if(camera!=null){
camera.release();
camera=null;
}
}
/**
*开始预览
*/
publicsynchronizedvoidstartPreview(){
Log.e(TAG,"startPreview");
CameratheCamera=camera;
if(theCamera!=null&&!previewing){
theCamera.startPreview();
previewing=true;
autoFocusManager=newAutoFocusManager(camera);
}
}
/**
*关闭预览
*/
publicsynchronizedvoidstopPreview(){
Log.e(TAG,"stopPreview");
if(autoFocusManager!=null){
autoFocusManager.stop();
autoFocusManager=null;
}
if(camera!=null&&previewing){
camera.stopPreview();
camera.setPreviewCallback(null);//CameraisbeingusedafterCamera.release()wascalled
previewing=false;
}
}
publicvoidsetPreviewCallback(Camera.PreviewCallbackcb){
camera.setOneShotPreviewCallback(this);
}
/**
*打开闪光灯
*/
publicsynchronizedvoidopenLight(){
Log.e(TAG,"openLight");
if(camera!=null){
parameters=camera.getParameters();
parameters.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH);
camera.setParameters(parameters);
}
}
/**
*关闭闪光灯
*/
publicsynchronizedvoidoffLight(){
Log.e(TAG,"offLight");
if(camera!=null){
parameters=camera.getParameters();
parameters.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);
camera.setParameters(parameters);
}
}
/**
*拍照
*
*@paramshutterShutterCallback
*@paramrawPictureCallback
*@paramjpegPictureCallback
*/
publicsynchronizedvoidtakePicture(finalCamera.ShutterCallbackshutter,finalCamera.PictureCallbackraw,
finalCamera.PictureCallbackjpeg){
camera.takePicture(shutter,raw,jpeg);
}
@Override
publicvoidonPreviewFrame(byte[]bytes,Cameracamera){
}
privateBitmapreSize(byte[]data){
Log.i(TAG,"myJpegCallback:onPictureTaken...");
BitmapcutMap=BitmapFactory.decodeByteArray(data,0,data.length);//data是字节数据，将其解析成位图
//设置FOCUS_MODE_CONTINUOUS_VIDEO)之后，myParam.set("rotation",90)失效。图片竟然不能旋转了，故这里要旋转下
Matrixmatrix=newMatrix();
matrix.postRotate((float)90.0);
BitmaprotaBitmap=Bitmap.createBitmap(cutMap,0,0,cutMap.getWidth(),cutMap.getHeight(),matrix,false);
//旋转后rotaBitmap是960×1280.预览surfaview的大小是540×800
//将960×1280缩放到540×800
BitmapsizeBitmap=Bitmap.createScaledBitmap(rotaBitmap,540,800,true);
BitmaprectBitmap=Bitmap.createBitmap(sizeBitmap,100,200,300,300);//截取
returnrectBitmap;
}
}
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持毛票票。