Android 开发 MediaRecorder使用Camera1配合录制视频

Posted 2021-12-28 guanxinjing

前言

　　MediaRecorder可以不依靠Camera API 实现视频的录制,但是如果需要切换摄像头/设置对焦/选择分辨率等等就需要Camera来参与配合录制视频.这篇博客将介绍使用Camera1来实现视频录制.此篇博客不在重复一些细节和坑的介绍.如果你刚接触建议你看我另一篇博客https://www.cnblogs.com/guanxinjing/p/10980906.html这篇博客用更简单易懂的形式说明了MediaRecorder录制视频的步骤,并且有大量深坑的详解介绍,防止你也掉坑里.

实现流程

1. 　　设置TextureView的硬件加速
2. 　　获取权限
3. 　　初始化TextureView的监听
4. 　　初始化MediaRecorder
5. 　　初始化Camera
6. 　　初始化配置Camera
7. 　　开始相机预览
8. 　　配置MediaRecorder(每次录制之前都需要配置一次)
9. 　　开始录制
10. 　　停止录制
11. 　　恢复相机预览

代码部分

　　关键点有大量注释,就不做另外篇幅的介绍

　　如果你对下面代码里的计算分辨率不甚理解,可以去我另一篇博客有更详细的讲解分辨率的计算,这篇博客虽然是拿Camera2 API来计算分辨率,但是原理是一样的. 传送门:https://www.cnblogs.com/guanxinjing/p/10943966.html

　　如果你对Camera自动对焦不太理解,可以去我另一篇更详细的博客有介绍Camera1的自动对焦. 传送门:https://www.cnblogs.com/guanxinjing/p/10986249.html

import androidx.appcompat.app.AppCompatActivity;
import android.graphics.SurfaceTexture;
import android.hardware.Camera;
import android.media.MediaRecorder;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.Surface;
import android.view.TextureView;
import android.view.View;
import android.widget.Button;
import java.io.File;
import java.io.IOException;
import java.util.List;

public class MedioRecorderCamera1Activity extends AppCompatActivity implements View.OnClickListener 
    private static final String TAG = MedioRecorderCamera1Activity.class.getSimpleName();
    private TextureView mTextureview;
    private Button mBtnStart, mBtnFinish;
    private MediaRecorder mMediaRecorder;
    private Camera mCamera;
    private Camera.Size mSelectSize;//记录当前选择的分辨率
    private boolean isRecorder = false;//用于判断当前是否在录制视频
    private Handler mHandler = new Handler()
        @Override
        public void handleMessage(Message msg) 
            super.handleMessage(msg);
            switch (msg.what)
                case 0x01:
                    mCamera.autoFocus(new Camera.AutoFocusCallback()  //自动对焦
                        @Override
                        public void onAutoFocus(boolean success, Camera camera) 

                        
                    );
                    mHandler.sendEmptyMessageDelayed(0x01,2*1000);//2秒之后在对焦一次,一直重复自动对焦
                    break;
                default:
                    break;
            
        
    ;

    @Override
    protected void onCreate(Bundle savedInstanceState) 
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_medio_recorder_camera1);
        mTextureview = findViewById(R.id.textureview);
        mBtnStart = findViewById(R.id.btn_start);
        mBtnFinish = findViewById(R.id.btn_finish);
        mBtnStart.setOnClickListener(this);
        mBtnFinish.setOnClickListener(this);
        initTextureViewListener();
        initMediaRecorder();

    

    /**
     * 初始化TextureView监听
     */
    private void initTextureViewListener()
        mTextureview.setSurfaceTextureListener(new TextureView.SurfaceTextureListener() 
            @Override
            public void onSurfaceTextureAvailable(SurfaceTexture surface, int width, int height)  //Textureview初始化启用回调
                initCamera();
                initCameraConfig();
                try 
                    mCamera.setPreviewTexture(surface);
                    mCamera.startPreview();
                    mHandler.sendEmptyMessage(0x01);//启动对焦
                 catch (IOException e) 
                    e.printStackTrace();
                

            

            @Override
            public void onSurfaceTextureSizeChanged(SurfaceTexture surface, int width, int height) 

            

            @Override
            public boolean onSurfaceTextureDestroyed(SurfaceTexture surface) 
                return false;
            

            @Override
            public void onSurfaceTextureUpdated(SurfaceTexture surface) 

            
        );
    


    @Override
    public void onClick(View v) 
        switch (v.getId())
            case R.id.btn_start:
                startRecorder();

                break;
            case R.id.btn_finish:
                stopRecorder();

                break;
            default:
                break;
        

    

    /**
     * 初始化MediaRecorder
     */
    private void initMediaRecorder()
        mMediaRecorder = new MediaRecorder();
    

    /**
     * 选择摄像头
     * @param isFacing true=前摄像头 false=后摄像头
     * @return 摄像id
     */
    private Integer selectCamera(boolean isFacing)
        int cameraCount = Camera.getNumberOfCameras();
//        CameraInfo.CAMERA_FACING_BACK 后摄像头
//        CameraInfo.CAMERA_FACING_FRONT  前摄像头
        int facing = isFacing ? Camera.CameraInfo.CAMERA_FACING_FRONT : Camera.CameraInfo.CAMERA_FACING_BACK;
        Log.e(TAG, "selectCamera: cameraCount="+cameraCount);
        if (cameraCount == 0)
            Log.e(TAG, "selectCamera: The device does not have a camera ");
            return null;
        
        Camera.CameraInfo info = new Camera.CameraInfo();
        for (int i=0; i < cameraCount; i++)
            Camera.getCameraInfo(i,info);
            if (info.facing == facing)
                return i;
            

        
        return null;

    

    /**
     * 初始化相机
     */
    private void initCamera()
        mCamera = Camera.open(selectCamera(false));
        mSelectSize = selectPreviewSize(mCamera.getParameters());


    

    /**
     * 初始化相机配置
     */
    private void initCameraConfig()
        Camera.Parameters parameters = mCamera.getParameters();
        parameters.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);//关闭闪光灯
        parameters.setFocusMode(Camera.Parameters.FLASH_MODE_AUTO); //对焦设置为自动
        parameters.setPreviewSize(mSelectSize.width,mSelectSize.height);//设置预览尺寸
        parameters.setPictureSize(mSelectSize.width,mSelectSize.height);//设置图片尺寸  就拿预览尺寸作为图片尺寸,其实他们基本上是一样的
        parameters.set("orientation", "portrait");//相片方向
        parameters.set("rotation", 90); //相片镜头角度转90度（默认摄像头是横拍）
        mCamera.setParameters(parameters);//添加参数
        mCamera.setDisplayOrientation(90);//设置显示方向

    

    /**
     * 计算获取预览尺寸
     * @param parameters
     * @return
     */
    private Camera.Size selectPreviewSize(Camera.Parameters parameters)
        List<Camera.Size> previewSizeList =  parameters.getSupportedPreviewSizes();
        if (previewSizeList.size() == 0)
            Log.e(TAG, "selectPreviewSize: previewSizeList size is 0" );
            return null;

        

        Camera.Size currentSelectSize = null;
        DisplayMetrics displayMetrics = getResources().getDisplayMetrics();
        int deviceWidth =displayMetrics.widthPixels;
        int deviceHeight = displayMetrics.heightPixels;
        for (int i = 1; i < 41 ; i++)
            for(Camera.Size itemSize : previewSizeList)
//                Log.e(TAG, "selectPreviewSize: itemSize 宽="+itemSize.width+"高"+itemSize.height);
                if (itemSize.height > (deviceWidth - i*5) && itemSize.height < (deviceWidth + i*5))
                    if (currentSelectSize != null) //如果之前已经找到一个匹配的宽度
                        if (Math.abs(deviceHeight-itemSize.width) < Math.abs(deviceHeight - currentSelectSize.width)) //求绝对值算出最接近设备高度的尺寸
                            currentSelectSize = itemSize;
                            continue;
                        
                    else 
                        currentSelectSize = itemSize;
                    

                

            
        
        Log.e(TAG, "selectPreviewSize: 当前选择的尺寸 宽="+currentSelectSize.width+"高"+currentSelectSize.height);
        return currentSelectSize;
    

    /**
     * 配置MedioRecorder
     */
    private void configMedioRecorder()
        File saveRecorderFile = new File(getExternalCacheDir(),"CameraRecorder.mp4");
        if (saveRecorderFile.exists())
            saveRecorderFile.delete();
        
        mCamera.unlock();
        mMediaRecorder.setCamera(mCamera);
        mMediaRecorder.setAudiosource(MediaRecorder.AudioSource.DEFAULT);//设置音频源
        mMediaRecorder.setVideoSource(MediaRecorder.VideoSource.DEFAULT);//设置视频源
        mMediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.DEFAULT);//设置音频输出格式
        mMediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.DEFAULT);//设置音频编码格式
        mMediaRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.DEFAULT);//设置视频编码格式
        mMediaRecorder.setVideoSize(mSelectSize.width,mSelectSize.height);//设置视频分辨率
        mMediaRecorder.setVideoEncodingBitRate(8*1920*1080);//设置视频的比特率
        mMediaRecorder.setVideoFrameRate(60);//设置视频的帧率
        mMediaRecorder.setOrientationHint(90);//设置视频的角度
        mMediaRecorder.setMaxDuration(60*1000);//设置最大录制时间
        Surface surface = new Surface(mTextureview.getSurfaceTexture());
        mMediaRecorder.setPreviewDisplay(surface);//设置预览
        mMediaRecorder.setOutputFile(saveRecorderFile.getAbsolutePath());//设置文件保存路径
        mMediaRecorder.setOnErrorListener(new MediaRecorder.OnErrorListener()  //录制异常监听
            @Override
            public void onError(MediaRecorder mr, int what, int extra) 
                mMediaRecorder.stop();
                mMediaRecorder.reset();
                try 
                    mCamera.setPreviewTexture(mTextureview.getSurfaceTexture());
                    mCamera.startPreview();
                 catch (IOException e) 
                    e.printStackTrace();
                

            
        );


    

    /**
     * 开启录制视频
     */
    private void startRecorder()
        if (!isRecorder) //如果不在录制视频
            mCamera.stopPreview();//暂停相机预览
            configMedioRecorder();//再次配置MedioRecorder
            try 
                mMediaRecorder.prepare();//准备录制
             catch (IOException e) 
                e.printStackTrace();
            
            mMediaRecorder.start();//开始录制
            isRecorder = true;
        

    

    /**
     * 停止录制视频
     */
    private void stopRecorder()
        if (isRecorder) //如果在录制视频
            mMediaRecorder.stop();//暂停录制
            mMediaRecorder.reset();//重置,将MediaRecorder调整为空闲状态
            isRecorder = false;
            try 
                mCamera.setPreviewTexture(mTextureview.getSurfaceTexture());//重新设置预览SurfaceTexture
                mCamera.startPreview(); //重新开启相机预览
                mCamera.autoFocus(new Camera.AutoFocusCallback() 
                    @Override
                    public void onAutoFocus(boolean success, Camera camera) 

                    
                );
             catch (IOException e) 
                e.printStackTrace();
            
        

    

    @Override
    protected void onDestroy() 
        super.onDestroy();
        if (mMediaRecorder != null)
            if (isRecorder) 
                mMediaRecorder.stop();
            
            mMediaRecorder.release();
            mMediaRecorder = null;
        
        if (mCamera != null)
            mCamera.stopPreview();
            mCamera.release();
            mCamera = null;