Android使用MediaRecorder实现录像功能

用MediaRecorder实现简单的录像功能

思路：定义一个SurfaceView用来显示预览，在SurfaceHolder的回调中用Camera对象启动预览。然后调用MediaRecorder来录像。仅仅是实现了简单的录像開始和停止功能。顶部能显示显示录像的时间，还有待完好。

代码例如以下：

在AndroidManifest.xml加入以下的权限：

<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />
<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<!-- 硬件支持 -->
<uses-feature android:name="android.hardware.camera"/>
<uses-feature android:name="android.hardware.camera.autofocus"/>
activity_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<SurfaceView
android:id="@+id/camera_preview"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:orientation="horizontal">
<TextView
android:id="@+id/timestamp_minute_prefix"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#7F00FF"
android:textSize="30sp"
android:text="0"/>
<TextView
android:id="@+id/timestamp_minute_text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#7F00FF"
android:textSize="30sp"
android:text="0"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#7F00FF"
android:textSize="30sp"
android:text=":"/>
<TextView
android:id="@+id/timestamp_second_prefix"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#7F00FF"
android:textSize="30sp"
android:text="0"/>
<TextView
android:id="@+id/timestamp_second_text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#7F00FF"
android:textSize="30sp"
android:text="0"/>
</LinearLayout>
<ImageButton
android:id="@+id/record_shutter"
android:layout_width="64dp"
android:layout_height="64dp"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="15dp"
android:background="@android:color/transparent"
android:scaleType="centerCrop"
android:src="@drawable/recording_shutter" />
</RelativeLayout>

MainActivity.java

package com.jackie.videorecorder;
import java.io.File;
import android.app.Activity;
import android.hardware.Camera;
import android.hardware.Camera.Parameters;
import android.hardware.Camera.Size;
import android.media.MediaRecorder;
import android.os.Bundle;
import android.os.Environment;
import android.os.Handler;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageButton;
import android.widget.TextView;
import org.w3c.dom.Text;
public class MainActivity extends Activity implements OnClickListener {
private SurfaceView mCameraPreview;
private SurfaceHolder mSurfaceHolder;
private ImageButton mShutter;
private TextView mMinutePrefix;
private TextView mMinuteText;
private TextView mSecondPrefix;
private TextView mSecondText;
private Camera mCamera;
private MediaRecorder mRecorder;
private final static int CAMERA_ID = 0;
private boolean mIsRecording = false;
private boolean mIsSufaceCreated = false;
private static final String TAG = "Jackie";
private Handler mHandler = new Handler();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mCameraPreview = (SurfaceView) findViewById(R.id.camera_preview);
mMinutePrefix = (TextView) findViewById(R.id.timestamp_minute_prefix);
mMinuteText = (TextView) findViewById(R.id.timestamp_minute_text);
mSecondPrefix = (TextView) findViewById(R.id.timestamp_second_prefix);
mSecondText = (TextView) findViewById(R.id.timestamp_second_text);
mSurfaceHolder = mCameraPreview.getHolder();
mSurfaceHolder.addCallback(mSurfaceCallback);
mSurfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
mShutter = (ImageButton) findViewById(R.id.record_shutter);
mShutter.setOnClickListener(this);
}
@Override
protected void onPause() {
super.onPause();
if (mIsRecording) {
stopRecording();
}
stopPreview();
}
private SurfaceHolder.Callback mSurfaceCallback = new SurfaceHolder.Callback() {
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
mIsSufaceCreated = false;
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
mIsSufaceCreated = true;
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
startPreview();
}
};
//启动预览
private void startPreview() {
//保证仅仅有一个Camera对象
if (mCamera != null || !mIsSufaceCreated) {
Log.d(TAG, "startPreview will return");
return;
}
mCamera = Camera.open(CAMERA_ID);
Parameters parameters = mCamera.getParameters();
Size size = getBestPreviewSize(CameraUtils.PREVIEW_WIDTH, CameraUtils.PREVIEW_HEIGHT, parameters);
if (size != null) {
parameters.setPreviewSize(size.width, size.height);
}
parameters.setFocusMode(Parameters.FOCUS_MODE_CONTINUOUS_VIDEO);
parameters.setPreviewFrameRate(20);
//设置相机预览方向
mCamera.setDisplayOrientation(90);
mCamera.setParameters(parameters);
try {
mCamera.setPreviewDisplay(mSurfaceHolder);
// mCamera.setPreviewCallback(mPreviewCallback);
} catch (Exception e) {
Log.d(TAG, e.getMessage());
}
mCamera.startPreview();
}
private void stopPreview() {
//释放Camera对象
if (mCamera != null) {
try {
mCamera.setPreviewDisplay(null);
} catch (Exception e) {
Log.e(TAG, e.getMessage());
}
mCamera.stopPreview();
mCamera.release();
mCamera = null;
}
}
private Camera.Size getBestPreviewSize(int width, int height, Camera.Parameters parameters) {
Camera.Size result = null;
for (Camera.Size size : parameters.getSupportedPreviewSizes()) {
if (size.width <= width && size.height <= height) {
if (result == null) {
result = size;
} else {
int resultArea = result.width * result.height;
int newArea = size.width * size.height;
if (newArea > resultArea) {
result = size;
}
}
}
}
return result;
}
@Override
public void onClick(View v) {
if (mIsRecording) {
stopRecording();
} else {
initMediaRecorder();
startRecording();
//開始录像后，每隔1s去更新录像的时间戳
mHandler.postDelayed(mTimestampRunnable, 1000);
}
}
private void initMediaRecorder() {
mRecorder = new MediaRecorder();//实例化
mCamera.unlock();
//给Recorder设置Camera对象，保证录像跟预览的方向保持一致
mRecorder.setCamera(mCamera);
mRecorder.setOrientationHint(90); //改变保存后的视频文件播放时是否横屏(不加这句。视频文件播放的时候角度是反的)
mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC); // 设置从麦克风採集声音
mRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA); // 设置从摄像头採集图像
mRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4); // 设置视频的输出格式 为MP4
mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.DEFAULT); // 设置音频的编码格式
mRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.H264); // 设置视频的编码格式
mRecorder.setVideoSize(176, 144); // 设置视频大小
mRecorder.setVideoFrameRate(20); // 设置帧率
// mRecorder.setMaxDuration(10000); //设置最大录像时间为10s
mRecorder.setPreviewDisplay(mSurfaceHolder.getSurface());
//设置视频存储路径
File file = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MOVIES) + File.separator + "VideoRecorder");
if (!file.exists()) {
//多级目录的创建
file.mkdirs();
}
mRecorder.setOutputFile(file.getPath() + File.separator + "VID_" + System.currentTimeMillis() + ".mp4");
}
private void startRecording() {
if (mRecorder != null) {
try {
mRecorder.prepare();
mRecorder.start();
} catch (Exception e) {
mIsRecording = false;
Log.e(TAG, e.getMessage());
}
}
mShutter.setImageDrawable(getResources().getDrawable(R.drawable.recording_shutter_hl));
mIsRecording = true;
}
private void stopRecording() {
if (mCamera != null) {
mCamera.lock();
}
if (mRecorder != null) {
mRecorder.stop();
mRecorder.release();
mRecorder = null;
}
mShutter.setImageDrawable(getResources().getDrawable(R.drawable.recording_shutter));
mIsRecording = false;
mHandler.removeCallbacks(mTimestampRunnable);
//将录像时间还原
mMinutePrefix.setVisibility(View.VISIBLE);
mMinuteText.setText("0");
mSecondPrefix.setVisibility(View.VISIBLE);
mSecondText.setText("0");
//重新启动预览
startPreview();
}
private Runnable mTimestampRunnable = new Runnable() {
@Override
public void run() {
updateTimestamp();
mHandler.postDelayed(this, 1000);
}
};
private void updateTimestamp() {
int second = Integer.parseInt(mSecondText.getText().toString());
int minute = Integer.parseInt(mMinuteText.getText().toString());
second++;
Log.d(TAG, "second: " + second);
if (second < 10) {
mSecondText.setText(String.valueOf(second));
} else if (second >= 10 && second < 60) {
mSecondPrefix.setVisibility(View.GONE);
mSecondText.setText(String.valueOf(second));
} else if (second >= 60) {
mSecondPrefix.setVisibility(View.VISIBLE);
mSecondText.setText("0");
minute++;
mMinuteText.setText(String.valueOf(minute));
} else if (minute >= 60) {
mMinutePrefix.setVisibility(View.GONE);
}
}
}

效果例如以下：

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脚本之家。

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