Android 使用摄像头拍照

在main.xml布局文件添加用于显示取景画面的SurfaceView 控件：

<SurfaceView android:layout_width="fill_parent" android:layout_height="240dip" android:id="@+id/surfaceView" />

SurfaceView surfaceView = (SurfaceView)this.findViewById(R.id.surfaceView);
surfaceView.getHolder().setFixedSize(176, 144); //设置分辨率
/*下面设置Surface不维护自己的缓冲区，而是等待屏幕的渲染引擎将内容推送到用户面前*/
surfaceView.getHolder().setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
Camera camera = Camera.open();
WindowManager wm = (WindowManager) getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();
Camera.Parameters parameters = camera.getParameters();
parameters.setPreviewSize(display.getWidth(), display.getHeight());//设置预览照片的大小
parameters.setPreviewFrameRate(3);//每秒3帧
parameters.setPictureFormat(PixelFormat.JPEG);//设置照片的输出格式
parameters.set("jpeg-quality", 85);//照片质量
parameters.setPictureSize(display.getWidth(), display.getHeight());//设置照片的大小
camera.setParameters(parameters);
camera.setPreviewDisplay(surfaceView.getHolder());//通过SurfaceView显示取景画面
camera.startPreview();//开始预览
camera.autoFocus(null);//自动对焦
camera.takePicture(null, null, null, jpegCallback);//拍照片
camera.stopPreview();//停止预览

camera.release();//释放摄像头

<uses-permission android:name="android.permission.CAMERA"/>

package cn.itcast.picture;

import java.io.File;
import java.io.FileOutputStream;
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.PixelFormat;
import android.graphics.Bitmap.CompressFormat;
import android.hardware.Camera;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.Display;
import android.view.KeyEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.Window;
import android.view.WindowManager;


public class TakePictureActivity extends Activity {
private static final String TAG = "TakePictureActivity";
    private SurfaceView surfaceView;
    private Camera camera;
    private boolean preview;
    
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Window window = getWindow();
    requestWindowFeature(Window.FEATURE_NO_TITLE);//没有标题
    window.setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);// 设置全屏
    window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);//高亮


        setContentView(R.layout.main);
        
        surfaceView = (SurfaceView) this.findViewById(R.id.surfaceView);
        surfaceView.getHolder().addCallback(new SufaceListener());
        /*下面设置Surface不维护自己的缓冲区，而是等待屏幕的渲染引擎将内容推送到用户面前*/
        surfaceView.getHolder().setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        surfaceView.getHolder().setFixedSize(176, 144);//设置分辨率
    }
    
    private final class SufaceListener implements SurfaceHolder.Callback{
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
try {
camera = Camera.open();//打开摄像头
Camera.Parameters parameters = camera.getParameters();
WindowManager wm = (WindowManager) getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();
parameters.setPreviewSize(display.getWidth(), display.getHeight());//设置预览照片的大小
parameters.setPreviewFrameRate(3);//每秒3帧
parameters.setPictureFormat(PixelFormat.JPEG);//设置照片的输出格式
parameters.set("jpeg-quality", 85);//照片质量
parameters.setPictureSize(display.getWidth(), display.getHeight());//设置照片的大小
camera.setParameters(parameters);
camera.setPreviewDisplay(surfaceView.getHolder());//通过SurfaceView显示取景画面
camera.startPreview();
preview = true;
} catch (Exception e) {
Log.e(TAG, e.toString());
}
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
if(camera!=null){
if(preview) camera.stopPreview();
camera.release();
camera = null;
}
}    
    }


@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if(camera!=null && event.getRepeatCount()==0){
switch (keyCode) {
case KeyEvent.KEYCODE_SEARCH:
camera.autoFocus(null);//自动对焦
break;
case KeyEvent.KEYCODE_DPAD_CENTER:
case KeyEvent.KEYCODE_CAMERA:
//拍照
camera.takePicture(null, null, new PictureCallbackListener());
break;
}
}
return true;
}

private final class PictureCallbackListener implements Camera.PictureCallback{
@Override
public void onPictureTaken(byte[] data, Camera camera) {
try {
Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);
File file = new File(Environment.getExternalStorageDirectory(), "itcast.jpg");
FileOutputStream outStream = new FileOutputStream(file);
bitmap.compress(CompressFormat.JPEG, 100, outStream);
outStream.close();
//重新浏览
camera.stopPreview();
camera.startPreview();
preview = true;
} catch (Exception e) {
Log.e(TAG, e.toString());
}
}
}
}

代码示例：

DemoActivity.java:

package cn.itcast.camera;import java.io.File;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import android.app.Activity;import android.graphics.PixelFormat;import android.hardware.Camera;import android.hardware.Camera.Parameters;import android.os.Bundle;import android.os.Environment;import android.util.Log;import android.view.SurfaceHolder;import android.view.SurfaceView;import android.view.View;import android.view.View.OnClickListener;import android.view.Window;import android.view.WindowManager;import android.widget.Button;import android.widget.Toast;public class DemoActivity extends Activity implements OnClickListener {private SurfaceView sv;private Button bt_take_pic, bt_auto_focus, bt_flash, bt_change;private SurfaceHolder holder;private Camera camera;Camera.Parameters parms;boolean flash = false;int index = 0;@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);// 隐藏掉activity的标题栏// 必须写到setcontentview之前requestWindowFeature(Window.FEATURE_NO_TITLE);// 实现窗体的全屏显示 隐藏通知栏内容getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);setContentView(R.layout.main);sv = (SurfaceView) this.findViewById(R.id.sv);bt_take_pic = (Button) this.findViewById(R.id.bt_take_pic);bt_auto_focus = (Button) this.findViewById(R.id.bt_auto_focus);bt_flash = (Button) this.findViewById(R.id.bt_flash);bt_change = (Button) this.findViewById(R.id.bt_change);bt_take_pic.setOnClickListener(this);bt_auto_focus.setOnClickListener(this);bt_flash.setOnClickListener(this);bt_change.setOnClickListener(this);sv.setOnClickListener(this);holder = sv.getHolder();holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);holder.addCallback(new MyHolderCallback());}public void onClick(View v) {switch (v.getId()) {case R.id.bt_auto_focus:// 自动对焦camera.autoFocus(null);break;case R.id.bt_take_pic:// 拍照// ShutterCallback// raw 未经过处理的意思camera.takePicture(null, null, new MyPicCallback());break;case R.id.bt_flash:if (flash) {// camera.stopPreview();parms.setFlashMode(Parameters.FLASH_MODE_OFF);camera.setParameters(parms);// camera.startPreview();flash = false;} else {// camera.stopPreview();parms.setFlashMode(Parameters.FLASH_MODE_TORCH);camera.setParameters(parms);// camera.startPreview();flash = true;}break;case R.id.bt_change:if (index == 0) {camera.release();camera = null;camera = Camera.open(1);camera.setParameters(parms);try {camera.setPreviewDisplay(holder);} catch (IOException e) {e.printStackTrace();}// 通过SurfaceView显示取景画面camera.startPreview();// 开始预览index = 1;} else {camera.release();camera = null;camera = Camera.open(0);camera.setParameters(parms);try {camera.setPreviewDisplay(holder);} catch (IOException e) {e.printStackTrace();}// 通过SurfaceView显示取景画面camera.startPreview();// 开始预览index = 0;}break;case R.id.sv:// 自动对焦camera.autoFocus(null);break;}}// 在照片生成以后调用的方法private class MyPicCallback implements Camera.PictureCallback {public void onPictureTaken(byte[] data, Camera camera) {if (Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState())) {try {File file = new File(Environment.getExternalStorageDirectory(),System.currentTimeMillis() + ".jpg");FileOutputStream fos = new FileOutputStream(file);fos.write(data);fos.flush();fos.close();} catch (Exception e) {Toast.makeText(getApplicationContext(), "保存照片失败,SD卡不可用", 0).show();e.printStackTrace();} finally {camera.startPreview();}} else {Toast.makeText(getApplicationContext(), "sd卡不可用", 0).show();}}}private class MyHolderCallback implements SurfaceHolder.Callback {public void surfaceCreated(SurfaceHolder holder) {System.out.println("holder 被创建 ");DemoActivity.this.holder = holder;camera = Camera.open(index);// 要想给照相机设置参数 必须要知道你的相机支持什么样子的参数// System.out.println(camera.getParameters().flatten());// 得到相机参数实例parms = camera.getParameters();parms.setPreviewFrameRate(5);parms.setPictureSize(1280, 960);parms.setPictureFormat(PixelFormat.JPEG);// 设置照片的输出格式parms.set("jpeg-quality", 100);// 照片质量// parms.setFlashMode(Parameters.FLASH_MODE_TORCH);camera.setParameters(parms);// 设置camera参数try {camera.setPreviewDisplay(holder);} catch (IOException e) {e.printStackTrace();}// 通过SurfaceView显示取景画面camera.startPreview();// 开始预览}public void surfaceChanged(SurfaceHolder holder, int format, int width,int height) {}public void surfaceDestroyed(SurfaceHolder holder) {System.out.println("holder被销毁");camera.release();camera = null;}}}

main.xml:

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="fill_parent"    android:layout_height="fill_parent"    android:orientation="vertical" >    <!-- layout_weight="100"设置优先级  数值越大优先级越低 -->    <SurfaceView        android:id="@+id/sv"        android:layout_width="fill_parent"        android:layout_height="fill_parent"        android:layout_weight="100" />    <RelativeLayout        android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:layout_weight="0" >        <Button            android:id="@+id/bt_take_pic"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:layout_alignParentRight="true"            android:text="拍照" />        <Button            android:id="@+id/bt_auto_focus"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:layout_alignParentTop="true"            android:layout_toLeftOf="@+id/bt_take_pic"            android:text="对焦" />        <Button            android:id="@+id/bt_flash"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:layout_alignParentTop="true"            android:layout_toLeftOf="@+id/bt_auto_focus"            android:text="闪光灯" />        <Button            android:id="@+id/bt_change"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:layout_alignParentTop="true"            android:layout_toLeftOf="@+id/bt_flash"            android:text="切换" />    </RelativeLayout></LinearLayout>

清单文件：

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="cn.itcast.camera"    android:versionCode="1"    android:versionName="1.0" >    <uses-sdk android:minSdkVersion="8" />    <uses-permission android:name="android.permission.CAMERA" />    <uses-feature android:name="android.hardware.camera" />    <uses-feature android:name="android.hardware.camera.autofocus" />    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />    <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />    <!-- screenOrientation="landscape"设置横屏显示 -->    <application        android:icon="@drawable/ic_launcher"        android:label="@string/app_name" >        <activity            android:name=".DemoActivity"            android:label="@string/app_name"            android:screenOrientation="landscape" >            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>    </application></manifest>