在Android上录制音频而不是文件

Question

I want android.media.MediaRecorder. to record audio not into file, but into same variable, for example char[ ] or byte[ ] or some other datta buffer structure. I want to send it to the remote server via Wi-Fi, can android.media.MediaRecorder provide this functionality?

Answer 1

What you can do here is utilize the ParcelFileDescriptor class.

//make a pipe containing a read and a write parcelfd
ParcelFileDescriptor[] fdPair = ParcelFileDescriptor.createPipe();

//get a handle to your read and write fd objects.
ParcelFileDescriptor readFD = fdPair[0];
ParcelFileDescriptor writeFD = fdPair[1];

//next set your mediaRecorder instance to output to the write side of this pipe.
mediaRecorder.setOutputFile(writeFD.getFileDescriptor());

//next create an input stream to read from the read side of the pipe.
FileInputStream reader = new FileInputStream(readFD.getFileDescriptor());

//now to fill up a buffer with data, we just do a simple read
byte[] buffer = new byte[4096];//or w/e buffer size you want

//fill up your buffer with data from the stream
reader.read(buffer);// may want to do this in a separate thread

and now you have a buffer full of audio data

alternatively, you may want to write data directly to a socket from the recorder. this can also be achieved with the ParcelFileDescriptor class.

//create a socket connection to another device
Socket socket = new Socket("123.123.123.123",65535);//or w/e socket address you are using

//wrap the socket with a parcel so you can get at its underlying File descriptor
ParcelFileDescriptor socketWrapper = ParcelFileDescriptor.fromSocket(socket);

//set your mediaRecorder instance to write to this file descriptor
mediaRecorder.setOutputFile(socketWrapper.getFileDescriptor());

now any time your media recorder has data to write it will automatically write it over the socket