DELPHI AREA Forum

I am trying to record using LiveAudioRecorder but can't seem to make it work to create a Wav file (they are always empty). I have read all messages on this board and looked at the source code and the Broadcaster example and passed hours trying averything and anything I can think of without success.

I am almost certain that its my OnData event that I am coding wrong. Does anyone have a sample code that could get me on the right track. I imagine its the way to use the Buffer value and/or the TWave that I am not getting.

Thank you

It would be nice if you post your code here to figure out what's wrong.

By the way, why you don't use TStockAudioRecorder to simplify this task?

Kambiz

I am using LiveAudioRecorder because I want the recording to stop if the noise level is below a certain level as in the Broadcaster example. I had no problem using the TStockAudioRecorder but cannot find a way to prevent the recording of low sound level portions.

I have tried so many things that I am posting the simplest code I have tried (and I am not good with pointers and maybe why I cannot get this to work)

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procedure TMainForm.LiveAudioRecorder1Data(Sender: TObject;
  const Buffer: Pointer; BufferSize: Cardinal; var FreeIt: Boolean);
begin
  if TheAudioLevel > MaxSilenceLevel then
  Begin
    AudioRecorder1.Wave.Write(Buffer, BufferSize);
  end;
end;

I have also tried using the Audiobuffer as in the Receiver example with no success, and a lot of other things. So I think that what is comes down to is how to use the buffer information to create a Wave file of the live recording.

Thank you for your help, your time and the Components you have created and put out as Freeware.

Firstly, you should consider that Buffer is a pointer, so you should write the buffer in to the stream as follow:

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Wave.Write(Buffer^, BufferSize);

Secondly, the RIFF format doesn't let you to create a wave file in this way.

Here is the procedure you should follow to create a wave file:

1. Include the required units to the uses clause of your unit.

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uses
  mmSystem, WaveUtils;

2. Declare the helper variables.

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var
  WaveFormatEx: TWaveFormatEx;
  ckInfo, ckData: TMMCKInfo;
  mmIO: HMMIO;

3. Initialize the wave content in OnActivate event of the LiveAudioRecorder.

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SetPCMAudioFormatS(@WaveFormatEx, LiveAudioRecorder.PCMFormat);
mmIO := CreateStreamWaveAudio(Stream, @WaveFormatEx, ckInfo, ckData);

Stream: could be any writable stream. For your case, I suggest to use TFileStream.

4. Add wave data to the stream in OnData event of the LiveAudioRecorder.

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mmioWrite(mmIO, Buffer, BufferSize);

5. Finalize the task in OnDeactivate event of the LiveAudioRecorder.

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CloseWaveAudio(mmio, ckInfo, ckData);

Hope that it helps.
Kambiz

WOW, it works. A BIG thank you for your time.
I Created Stream as a TWave and just added : Stream.SaveToFile('MyPath\Name.WAV'); after the CloseWaveAudio.

With this code I also understood a couple of your other routines and some TWave manipulation.

Once again thank you