Author: Tomas Rutkauskas

I'm trying to use MediaPlayer to record sound into a wave file through a 
microphone. Can someone show me some simple code to do the recording?

Answer:

The TMediaPlayer can only open a wave file that has at least one byte of data in 
it. I found this out when I tried to create and open a wave file that was nothing 
but a wave header. The TMediaPlayer wouldn't do it. The following code creates a 
wave file with a single byte of data at the beginning. It is a bit of a kludge to 
do it this way, but it works. You need to add MMSYSTEM to the uses clause of any 
unit that uses this function.


1   function CreateNewWave(NewFileName: string): Boolean;
2   var
3     DeviceID: Word;
4     Return: LongInt;
5     MciOpen: TMCI_Open_Parms;
6     MciRecord: TMCI_Record_Parms;
7     MciPlay: TMCI_Play_Parms;
8     MciSave: TMCI_SaveParms;
9     MCIResult: LongInt;
10    Flags: Word;
11    TempFileName: array[0..255] of char;
12  begin
13    MediaPlayer.Close;
14    StrPCopy(TempFileName, NewFileName);
15    MciOpen.lpstrDeviceType := 'waveaudio';
16    MciOpen.lpstrElementName := '';
17    Flags := Mci_Open_Element or Mci_Open_Type;
18    MCIResult := MciSendCommand(0, MCI_OPEN, Flags, LongInt(@MciOpen));
19    DeviceID := MciOpen.wDeviceId;
20    MciRecord.dwTo := 1;
21    Flags := Mci_To or Mci_Wait;
22    MCIResult := MciSendCommand(DeviceID, Mci_Record, Flags, LongInt(@MciRecord));
23    mciPlay.dwFrom := 0;
24    Flags := Mci_From or Mci_Wait;
25    MciSendCommand(DeviceId, Mci_Play, Flags, LongInt(@MciPlay));
26    mciSave.lpfileName := TempFilename;
27    Flags := MCI_Save_File or Mci_Wait;
28    MCIResult := MciSendCommand(DeviceID, MCI_Save, Flags, LongInt(@MciSave));
29    Result := MciSendCommand(DeviceID, Mci_Close, 0, LongInt(nil)) = 0;
30  end;