Android recording and playback

 

need to do a job today while recording while playback functions, generally because there is an external device input audio into our machine, and then we need to immediately put audio playback machines out. So learn some knowledge about recording and playback. Receive this task first reaction is to look inside the recording source Android Demo, so today's recording demo program for Android explain some knowledge of recording and playback.

 

explain today mainly use MediaRecorder achieve recording, mainly with reference to Android official website describes to illustrate.

 

talked about today and can not be achieved while recording while playing, the next article I will say how to solve this problem. Here we have to explain Mediarecorder state machine diagram. Extracted from Android's official website.

 

 

(PS: the new QQ group, who are interested can join together to discuss: Android group: 322599434)

 

 

1, using Mediarecorder recording

 

MediaRecorder class is used for media sampling, including audio and video. Is the method used to record audio and video classes are generally recorded data is written to the file inside. Therefore, we can use this class implements audio and video recording capabilities. The following describes a simple method for recording MediaRecorder:

 

  

//Edited by mythou
//http://www.cnblogs.com/mythou/

  

 MediaRecorder recorder = new MediaRecorder(); 
 recorder.setAudioSource(MediaRecorder.AudioSource.MIC); 
 recorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP); 
 recorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB); 
 recorder.setOutputFile(PATH_NAME); 
 recorder.prepare(); 
 recorder.start();   // 开始录音 
 
 ... 
 recorder.stop(); 
 recorder.reset();   // You can reuse the object by going back to setAudioSource() step 
 recorder.release(); // Now the object cannot be reused

 

 

The above is a simple process using MediaRecorder recording code, basically you use the code, you can achieve recording function.

 

 

2, MediaRecorder related classes

 

  

  

//Edited by mythou
//http://www.cnblogs.com/mythou/

  

//定义音频编码 
class MediaRecorder.AudioEncoder 
 
//定义声音资源 
class MediaRecorder.AudioSource 
 
//回调接口，当录音出现错误的时候调用 
interface  MediaRecorder.OnErrorListener 
 
//回调接口，当录音出现错误的时候调用 
interface MediaRecorder.OnInfoListener 
 
//定义输出格式 
class MediaRecorder.OutputFormat 
  
//定义视频编码 
class MediaRecorder.VideoEncoder 
 
//定义视频source 
class MediaRecorder.VideoSource

 

 

 

3, MediaRecorder common method

 

  

  

//Edited by mythou
//http://www.cnblogs.com/mythou/

  

//获取音频信号源的最高值。 
final static int getAudioSourceMax() 
 
 //最后调用这个方法采样的时候返回最大振幅的绝对值 
int getMaxAmplitude() 
 
//准备recorder 开始捕获和编码数据 
void prepare() 
 
//发布与此MediaRecorder对象关联的资源 
void release() 
 
//重新启动mediarecorder到空闲状态 
void reset() 
 
//设置录制的音频通道数。 
void setAudioChannels(int numChannels) 
 
//设置audio的编码格式 
void setAudioEncoder(int audio_encoder) 
 
//设置录制的音频编码比特率 
void setAudioEncodingBitRate(int bitRate) 
  
//设置录制的音频采样率。 
void setAudioSamplingRate(int samplingRate) 
 
//设置用于录制的音源。 
void setAudioSource(int audio_source) 
 
//辅助时间的推移视频文件的路径传递。 
void setAuxiliaryOutputFile(String path) 
 
void setAuxiliaryOutputFile(FileDescriptor fd) 
//在文件描述符传递的辅助时间的推移视频 
  
//设置一个recording的摄像头 
void setCamera(Camera c) 
 
//设置视频帧的捕获率 
void setCaptureRate(double fps) 
 
//设置记录会话的最大持续时间（毫秒） 
void setMaxDuration(int max_duration_ms) 
 
//设置记录会话的最大大小（以字节为单位） 
void setMaxFileSize(long max_filesize_bytes) 
 
//注册一个回调被调用发生错误时，同时录制 
void setOnErrorListener(MediaRecorder.OnErrorListener l) 
 
//注册要同时记录一个信息事件发生时调用的回调。 
void setOnInfoListener(MediaRecorder.OnInfoListener listener) 
  
//设置输出的视频播放的方向提示 
void setOrientationHint(int degrees) 
 
//传递要写入的文件的文件描述符 
void setOutputFile(FileDescriptor fd) 
 
//设置输出文件的路径 
void setOutputFile(String path) 
 
//设置在录制过程中产生的输出文件的格式 
void setOutputFormat(int output_format) 
 
//表面设置显示记录媒体（视频）的预览 
void setPreviewDisplay(Surface sv) 
 
//从一个记录CamcorderProfile对象的使用设置 
void setProfile(CamcorderProfile profile) 
 
//设置视频编码器，用于录制 
void setVideoEncoder(int video_encoder) 
 
//设置录制的视频编码比特率 
void setVideoEncodingBitRate(int bitRate) 
  
//设置要捕获的视频帧速率 
void setVideoFrameRate(int rate) 
 
//设置要捕获的视频的宽度和高度 
void setVideoSize(int width, int height) 
 
//开始捕捉和编码数据到setOutputFile（指定的文件） 
void setVideoSource(int video_source) 
 
//开始录音 
void start() 
 
//停止recording 
void stop()

 

 

 

4, play audio

 

  

//Edited by mythou
//http://www.cnblogs.com/mythou/

  

mPlayer = new MediaPlayer(); 
mPlayer.setDataSource(mSampleFile.getAbsolutePath()); 
mPlayer.setOnCompletionListener(this); 
mPlayer.setOnErrorListener(this); 
mPlayer.prepare(); 
mPlayer.start(); 
 
//....... 
mPlayer.stop(); 
mPlayer.release(); 
mPlayer = null;

 

 

above is a simple playback recording process, combined with the above recording code, you can achieve recording and playback.

 

MediaRecorder's very simple to use, and finally gives Android source inside the recording procedures are in need of a friend downloaded. Next article then explains how to achieve while recording while playback.

 

 

Android recording program download: SoundRecorder8 -6.rar

 

 

Edited by mythou

 

original blog, reproduced, please indicate the source: http://www .cnblogs.com/mythou/p/3242000.html