Android:照相机（camera）与视频录制(Recorder)的实现

来源：互联网发布：c语言自学软件编辑：程序博客网时间：2024/04/25 18:07

在我们开发app时，会遇到程序中需要摄像的功能，我们最好的选择是跳转到手机自带的摄像程序中，但有时侯也可以在自己的应用程序中实现这个东西。

要用到的控件：SurfaceView显示照相机的画面

实现照相机的核心类：camera
- surfaceView.getHolder().addCallback()接受摄像头界面变化的信息
实现视频录制的核心类：MediaRecorder

实现照相机

activity_main.xml:

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools" android:id="@+id/activity_main"    android:layout_width="match_parent" android:layout_height="match_parent"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"  android:paddingTop="@dimen/activity_vertical_margin"    android:orientation="vertical"    tools:context="com.example.android27_camera.MainActivity">    <SurfaceView        android:layout_width="match_parent"        android:layout_height="0dp"        android:layout_weight="1"        android:id="@+id/sv_Camera"        />    <Button        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:onClick="takePhoto"        android:text="拍照"        /></LinearLayout>

MainActivity.java

package com.example.android27_camera;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.PixelFormat;import android.hardware.Camera;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.view.SurfaceHolder;import android.view.SurfaceView;import android.view.View;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;public class MainActivity extends AppCompatActivity {    private SurfaceView sv_camera;    private Camera camera;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        //surfaceView显示容器        sv_camera = (SurfaceView) findViewById(R.id.sv_Camera);        sv_camera.getHolder().addCallback(new SurfaceHolder.Callback() {            @Override            public void surfaceCreated(SurfaceHolder holder) {                //打开摄像头(默认为后置摄像头，1为前置)                camera = Camera.open(1);                //给摄像设置参数                Camera.Parameters parameters= camera.getParameters();                //每秒几栈//                parameters.setPreviewFrameRate(3);                //设置照片的输出格式                parameters.setPictureFormat(PixelFormat.JPEG);                //设置照片质量                parameters.set("jpeg-quality",85);                //给照相机设置参数                camera.setParameters(parameters);                try {                    //将摄像头的画面显示在SurfaceView上                    camera.setPreviewDisplay(sv_camera.getHolder());                } catch (IOException e) {                    e.printStackTrace();                }                //开始预览                camera.startPreview();            }            @Override            public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {            }            @Override            public void surfaceDestroyed(SurfaceHolder holder) {                camera.stopPreview();                camera.release();                camera=null;            }        });    }    //拍照    public void takePhoto(View view){        camera.takePicture(null, null, new Camera.PictureCallback() {//拍照回调函数            @Override            public void onPictureTaken(byte[] data, Camera camera) {                Bitmap bitmap= BitmapFactory.decodeByteArray(data,0,data.length);                try {                    //写入本地内存卡中                    FileOutputStream fos=new FileOutputStream("mnt/sdcard/DCIM/camera/myCamera"+System.currentTimeMillis()+".png");                    //压缩文件                    bitmap.compress(Bitmap.CompressFormat.PNG,85,fos);                    //先停止预览                    camera.stopPreview();                    //在开启                    camera.startPreview();                } catch (FileNotFoundException e) {                    e.printStackTrace();                }            }        });    }}

 <!-- 读取外部存储 -->    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" /><!-- 获得摄像头权限 -->    <uses-permission android:name="android.permission.CAMERA" />    <!--获得存储的权限-->    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

下面是视频录制

activity_media_recorder.xml:

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:id="@+id/activity_media_recorder"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context="com.example.android27_camera.MediaRecorderActivity">    <SurfaceView        android:layout_width="match_parent"        android:layout_height="350dp"        android:id="@+id/sv_recorder"        />    <LinearLayout        android:layout_width="match_parent"        android:layout_height="wrap_content">        <Button            android:layout_weight="1"            android:layout_width="0dp"            android:text="开始"            android:onClick="start"            android:layout_height="wrap_content" />        <Button            android:layout_weight="1"            android:layout_width="0dp"            android:text="停止"            android:onClick="stop"            android:layout_height="wrap_content" />    </LinearLayout></LinearLayout>

MediaRecorderActivity.java:

package com.example.android27_camera;import android.media.MediaRecorder;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.view.SurfaceView;import android.view.View;import java.io.IOException;import static android.os.Build.VERSION_CODES.M;public class MediaRecorderActivity extends AppCompatActivity {    private SurfaceView sv_recorder;    private MediaRecorder mediaRecorder;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_media_recorder);        sv_recorder = (SurfaceView) findViewById(R.id.sv_recorder);        //实例化媒体录制器        mediaRecorder = new MediaRecorder();    }    public void start(View view){        //重置媒体录制器        mediaRecorder.reset();        //设置音频和视频来源        //照相机        mediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);        //麦克风        mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);        //设置保存格式        mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);        //设置编码格式        mediaRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.H263);        mediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);        //设置每秒几帧        mediaRecorder.setVideoFrameRate(3);        //设置保存的路径        mediaRecorder.setOutputFile("mnt/sdcard/MyRecorder"+System.currentTimeMillis()+".mp4");        //将画面展示到SurfaceView        mediaRecorder.setPreviewDisplay(sv_recorder.getHolder().getSurface());        try {            //准备            mediaRecorder.prepare();            //启动            mediaRecorder.start();        } catch (IOException e) {            e.printStackTrace();        }    }    public void stop(View view){        mediaRecorder.stop();    }}

最后别忘了加权限

<!--添加媒体录制器权限-->    <uses-permission android:name="android.permission.RECORD_AUDIO"></uses-permission>

源码下载：

http://download.csdn.net/download/james_lang/9761933

0 0