How to record a telephone call into a wave file ?

[Guest]

Hi all

This is part of a power basic TAM project.
Recording audio via microphone and soundcard into a wave file works great.
Making phone calls with my voice modem and headset (connected to soundcard) works either.

But i´m not able to record incoming audio from my modem.
i use a Motorola SM56 Speakerphone (PCI). Control panel tells me, there is a
wave driver installed for this modem. audio transfer between modem and soundcard
works (otherwise my headset couldn´t work). The modem manual states DirectX
version 6 must be installed for audio transfer to work. On the other hand
WaveInGetNumDevs() returns "2" (default audio input device = soundcard [deviceid=0],
second input device = "modem nr. 0" [deviceid=1]), meaning this modem is a
wave input device.

If i query the modem device, i get dwformats=0 [wave_invalidformat] and
wchannels=1 in waveincaps structure in return, meaning it doesn´t support
wave format (?) but it offers input for one channel. (???)

So what, if it is listed as a wave input device, why doesn´t it support
wave format? .

How does DirectX audio capture work ? maybe this could be a way to do it.


Any ideas about this, i´m stuck with it since several days ...


Thanks in advance,

Guenther



below some testing code i use (put together from code sample i found):


#COMPILE EXE
#DIM ALL

%USEMACROS = 1
#INCLUDE "Win32API.inc"

$ComPort = "COM3"
$AppTitle = "PB/Win Comm Example"

%IDD_MAIN = 100
%IDC_LISTBOX1 = 101
%IDC_EDIT1 = 102
%IDC_SEND = 103
%IDC_SENDFILE = 104
%IDC_RECEIVEFILE = 105
%IDC_QUIT = 106
%IDC_ECHO = 107



GLOBAL nComm AS LONG ' file number of comm device
GLOBAL nWriteFile AS LONG ' file number of output file
GLOBAL fUpdating AS LONG ' flag to avoid conflicts when updating
GLOBAL fCloseThread AS LONG ' flag to tell thread to shut down

GLOBAL hwi AS LONG

'***********************************************************************************************


CALLBACK FUNCTION check_callback
'***********************************************************************************************
'
'***********************************************************************************************
'FUNCTION OpenWaveIn(BYVAL hWnd AS LONG) AS LONG
LOCAL rc AS LONG
LOCAL NumDevs AS DWORD
LOCAL i AS LONG
LOCAL ErrStr AS ASCIIZ*512
LOCAL wfx AS WAVEFORMATEX
LOCAL wic AS WAVEINCAPS

rc = WaveInGetNumDevs()

FOR i = 0 TO rc -1
' FOR i = 1 TO rc -1
rc = WaveInGetDevCaps(i, wic, LEN(WAVEINCAPS))
IF (rc = %MMSYSERR_NOERROR) THEN

MSGBOX wic.szpname+" --- "+HEX$(wic.dwformats)+" --- "+STR$(wic.wchannels)

' IF wic.dwFormats AND %WAVE_FORMAT_1M16 THEN
wfx.nChannels = 1
wfx.nSamplesPerSec = 11025
wfx.wFormatTag = %WAVE_FORMAT_PCM
wfx.wBitsPerSample = 16
wfx.nBlockAlign = wfx.nChannels * wfx.wBitsPerSample \ 8
wfx.nAvgBytesPerSec = wfx.nSamplesPerSec * wfx.nBlockAlign
wfx.cbSize = 0
' rc = waveinOpen(hwi, i, wfx, hWnd, hWnd, %CALLBACK_WINDOW)
IF (rc = %MMSYSERR_NOERROR) THEN
FUNCTION = %True
' EXIT FUNCTION
ELSE
WaveInGetErrorText rc, ErrStr, 511
MSGBOX ErrStr
END IF
' ELSE
MSGBOX "Device " & wic.szpName & " - WAVE_FORMAT_1M16 Not Supported"
' END IF
ELSE
WaveInGetErrorText rc, ErrStr, 127
MSGBOX ErrStr
END IF
NEXT i

MSGBOX "No suitable device found"

FUNCTION = %False

END FUNCTION


'***********************************************************************************************
SUB AddLine (BYVAL hWnd AS DWORD, BYVAL nID AS LONG, SendText AS ASCIIZ)
'***********************************************************************************************
'
'***********************************************************************************************
LOCAL ListCount AS LONG

' find the current listbox count
CONTROL SEND hWnd, nID, %LB_GETCOUNT, 0, 0 TO ListCount

' update the listbox
CONTROL SEND hWnd, nID, %LB_ADDSTRING, 0, VARPTR(SendText)

' scroll the new item into view
CONTROL SEND hWnd, nID, %LB_SETCURSEL, ListCount, 0

END SUB


'***********************************************************************************************


FUNCTION StartComms () AS LONG
'***********************************************************************************************
'
'***********************************************************************************************
LOCAL dummy AS STRING

COMM OPEN $COMPORT AS #nComm
IF ERRCLEAR THEN EXIT FUNCTION ' Exit if port cannot be opened

COMM SET #nComm, BAUD = 9600 ' 9600 baud
COMM SET #nComm, BYTE = 8 ' 8 bits
COMM SET #nComm, PARITY = %False ' No parity
COMM SET #nComm, STOP = 0 ' 1 stop bit
COMM SET #nComm, TXBUFFER = 4096 ' 4k transmit buffer
COMM SET #nComm, RXBUFFER = 4096 ' 4k receive buffer

' Issue a CR/LF and flush the receive buffer
COMM PRINT #nComm, $NUL
SLEEP 2000
IF COMM(#nComm, RXQUE) THEN COMM RECV #nComm, COMM(#nComm, RXQUE), dummy

FUNCTION = %TRUE

END FUNCTION


'***********************************************************************************************


SUB EndComms ()
'***********************************************************************************************
'
'***********************************************************************************************
LOCAL dummy AS STRING

' Flush the RX buffer & close the port
SLEEP 1000

IF COMM(#nComm, RXQUE) THEN
COMM RECV #nComm, COMM(#nComm, RXQUE), dummy
END IF

COMM CLOSE #nComm

END SUB


'***********************************************************************************************


FUNCTION ReceiveData (BYVAL hWnd AS LONG) AS LONG
'***********************************************************************************************
'
'***********************************************************************************************
LOCAL sBigBuffer AS STRING
LOCAL sBuffer AS STRING
LOCAL ncBytesInBuffer AS LONG


WHILE ISFALSE fCloseThread

' Test the RX buffer
ncBytesInBuffer = COMM(#nComm, RXQUE)

' Abort this iteration if sending
IF ISFALSE ncBytesInBuffer OR fUpdating THEN
SLEEP 100
ITERATE LOOP
END IF

' Read incoming characters.
COMM RECV #nComm, ncBytesInBuffer, sBuffer
sBigBuffer = sBigBuffer & sBuffer

' If Receive mode is on, write raw data to the file
IF nWriteFile THEN PRINT #nWriteFile, sBuffer;

' Strip out LF characters
REPLACE $LF WITH "" IN sBigBuffer

' Process only complete lines of text terminated by carriage returns
WHILE INSTR(sBigBuffer, $CR)
' Display the data
AddLine hWnd, %IDC_LISTBOX1, "==> " + EXTRACT$(sBigBuffer, $CR)

' Remove the "displayed" line from the buffer
sBigBuffer = STRDELETE$(sBigBuffer, 1, LEN(EXTRACT$(sBigBuffer, $CR)) + 1)
WEND
WEND

FUNCTION = %TRUE


END FUNCTION


'***********************************************************************************************


CALLBACK FUNCTION Dialog_Callback () AS LONG
'***********************************************************************************************
'
'***********************************************************************************************


IF CBMSG = %WM_INITDIALOG THEN
' Set focus to the edit control
CONTROL SET FOCUS CBHNDL, %IDC_EDIT1

' Set the SELECTION range to highlight the initial entry
CONTROL SEND CBHNDL, %IDC_EDIT1, %EM_SETSEL, 0, -1

' Return 0 to stop the dialog box engine setting focus
FUNCTION = %FALSE
END IF


END FUNCTION


'***********************************************************************************************


CALLBACK FUNCTION Send_Callback () AS LONG
'***********************************************************************************************
'
'***********************************************************************************************
LOCAL SendText AS ASCIIZ * 1024
LOCAL Result AS LONG
LOCAL hListBox AS DWORD

' Obtain the text to send from the edit control
CONTROL GET TEXT CBHNDL, %IDC_EDIT1 TO SendText

' Set the update flag
fUpdating = %TRUE

' Send the line to the comm port
COMM PRINT #nComm, SendText

' Check the Echo mode state
CONTROL SEND CBHNDL, %IDC_ECHO, %BM_GETCHECK, 0, 0 TO Result
IF Result <> %BST_CHECKED THEN
' Add the echo to the listbox
AddLine CBHNDL, %IDC_LISTBOX1, "<== " + SendText
END IF

' Set the SELECTION range for the edit control so the next keypress "clears" the control
CONTROL SEND CBHNDL, %IDC_EDIT1, %EM_SETSEL, 0, -1

' Restore the keyboard focus to the edit control
CONTROL SET FOCUS CBHNDL, %IDC_EDIT1

' Release the update flag
fUpdating = %FALSE

FUNCTION = %TRUE

END FUNCTION


'***********************************************************************************************


CALLBACK FUNCTION SendFile_Callback() AS LONG
'***********************************************************************************************
'
'***********************************************************************************************
LOCAL SendFileName AS STRING
LOCAL nReadFile AS LONG
LOCAL FileLen AS LONG
LOCAL Chunk AS LONG
LOCAL i AS LONG
LOCAL sBuffer AS STRING


SendFileName = INPUTBOX$("Name of disk file to transmit? ", $AppTitle, "")
IF ISFALSE LEN(SendFileName) OR ISFALSE LEN(DIR$(SendFileName)) THEN
EXIT FUNCTION
END IF

AddLine CBHNDL, %IDC_LISTBOX1, "Wait... Sending " & SendFileName
DIALOG DOEVENTS

' send the file
nReadFile = FREEFILE
OPEN SendFileName FOR BINARY AS #nReadFile ' Open as binary
FileLen = LOF(nReadFile) ' File length
Chunk = COMM(#nComm, TXBUFFER) \ 2 ' 1/2 * TXBUFFER

FOR i = 1 TO FileLen \ Chunk
GET$ #nReadFile, Chunk, sBuffer ' Read a chunk
COMM SEND #nComm, sBuffer ' and send it
SLEEP 0
NEXT i

IF FileLen MOD Chunk <> 0 THEN ' More to send?
GET$ #nReadFile, FileLen MOD Chunk, sBuffer
COMM SEND #nComm, sBuffer
END IF

CLOSE #nReadFile

AddLine CBHNDL, %IDC_LISTBOX1, "Transmission complete!"

END FUNCTION


'***********************************************************************************************

CALLBACK FUNCTION ReceiveFile_Callback () AS LONG
'***********************************************************************************************
'
'***********************************************************************************************
LOCAL sReceiveFileName AS STRING
LOCAL sBuffer AS STRING

' First check if file is already open
IF nWriteFile THEN
CLOSE #nWriteFile 'close the file
AddLine CBHNDL, %IDC_LISTBOX1, "Finished writing file!"

' Update the button label
sBuffer = "&Receive File"
CONTROL SEND CBHNDL, %IDC_RECEIVEFILE, %WM_SETTEXT, 0, STRPTR(sBuffer)

nWriteFile = 0
EXIT FUNCTION
END IF

' Create a new file
sReceiveFileName = INPUTBOX$("Output file name?", $AppTitle, "")
IF ISFALSE LEN(sReceiveFileName) THEN EXIT FUNCTION

nWriteFile = FREEFILE

OPEN sReceiveFileName FOR APPEND AS #nWriteFile
IF ERRCLEAR THEN
' Error opening the file
nWriteFile = 0
ELSE
' Update the dialog
AddLine CBHNDL, %IDC_LISTBOX1, "Receiving data stream to " & sReceiveFileName
sBuffer = "Stop &Receive"
CONTROL SEND CBHNDL, %IDC_RECEIVEFILE, %WM_SETTEXT, 0, STRPTR(sBuffer)
END IF

END FUNCTION


'***********************************************************************************************


CALLBACK FUNCTION Quit_Callback () AS LONG
'***********************************************************************************************
'
'***********************************************************************************************

' Kill the dialog and let PBMAIN() continue
DIALOG END CBHNDL, 0

END FUNCTION


'***********************************************************************************************


FUNCTION PBMAIN () AS LONG
'***********************************************************************************************
'
'***********************************************************************************************
#REGISTER NONE

LOCAL hDlg AS DWORD
LOCAL Result AS LONG
LOCAL hThread AS LONG
DIM Txt(1 TO 1) AS STRING


' Initialize the port ready for the session
IF ISFALSE StartComms THEN
MSGBOX "Failed to start communications!",, $AppTitle
EXIT FUNCTION
END IF

Txt(1) = "This listbox shows the transmission I/O stream..."

' Create a modal dialog box
DIALOG NEW 0, $AppTitle,,, 330, 203, %WS_POPUP OR %WS_VISIBLE OR %WS_CLIPCHILDREN OR %WS_CAPTION OR %WS_SYSMENU OR %WS_MINIMIZEBOX, 0 TO hDlg

' Add our application controls
CONTROL ADD LABEL, hDlg, -1, "Transmission &log for " & $ComPort, _
9, 5, 100, 10, 0

CONTROL ADD LISTBOX, hDlg, %IDC_LISTBOX1, Txt(), 9, 15, 313, 133, _
%WS_BORDER OR %LBS_WANTKEYBOARDINPUT _
OR %LBS_DISABLENOSCROLL OR %WS_VSCROLL OR %WS_GROUP _
OR %WS_TABSTOP OR %LBS_NOINTEGRALHEIGHT

CONTROL ADD LABEL, hDlg, -1, "Te&xt to send", 9, 151, 100, 10, 0

CONTROL ADD TEXTBOX, hDlg, %IDC_EDIT1, "ATZ", 9, 161, 257, 12, _
%ES_AUTOHSCROLL OR %ES_NOHIDESEL OR %WS_BORDER _
OR %WS_GROUP OR %WS_TABSTOP

CONTROL ADD BUTTON, hDlg, %IDC_SEND, "Send &Text", 273, 160, 50, 14, _
%WS_GROUP OR %WS_TABSTOP OR %BS_DEFPUSHBUTTON _
CALL Send_Callback

CONTROL ADD BUTTON, hDlg, %IDC_SENDFILE, "&Send File", 9, 182, 50, 14, _
%WS_GROUP OR %WS_TABSTOP CALL SendFile_Callback

CONTROL ADD BUTTON, hDlg, %IDC_RECEIVEFILE, "&Receive File", _
62, 182, 50, 14, %WS_GROUP OR %WS_TABSTOP _
CALL ReceiveFile_Callback

CONTROL ADD BUTTON, hDlg, %IDC_QUIT, "&Quit", 273, 182, 50, 14, _
%WS_GROUP OR %WS_TABSTOP CALL Quit_Callback

CONTROL ADD BUTTON, hDlg, 500, "check", 150, 182, 50, 14, _
%WS_GROUP OR %WS_TABSTOP CALL check_Callback



CONTROL ADD CHECKBOX, hDlg, %IDC_ECHO, "Disable Local &Echo", _
241, 5, 80, 10, _
%WS_GROUP OR %WS_TABSTOP OR %BS_AUTOCHECKBOX _
OR %BS_LEFTTEXT OR %BS_RIGHT

' Erase our array to free memory no longer required
REDIM Txt()

' Create a "listen" thread to monitor input from the modem
THREAD CREATE ReceiveData(hDlg) TO hThread

' Start the dialog box & run until DIALOG END executed.
DIALOG SHOW MODAL hDlg, CALL Dialog_Callback TO Result

' close down our "listen" thread
fCloseThread = %TRUE
DO
THREAD CLOSE hThread TO Result
SLEEP 0
LOOP UNTIL ISTRUE Result

' Flush & close the comm port and close the Receive file if open
EndComms

IF nWriteFile THEN CLOSE #nWriteFile


END FUNCTION

'***********************************************************************************************
'***********************************************************************************************

[Cliff Nichols]

Looks like typical Serial Port code (could use code tags though), but I see nothing about audio from a modem?

code tags are typically
[ c o d e ]

[ / c o d e ]


and take out the spaces for code and end-code

[Guest]

Sorry for the code thing, will try to make it better next time !

audio cap test code is in check_callback. As mentioned before
capturing audio from mircophone and getting it into a wave file
is not the problem.

The problem is, audio input from modem does not work after
establishing a call with AT commands. I can hear audio in my
headset, which tells me, there is a way to transfer audio from
modem to the soundcard. But i cannot get this audio data recorded
like i can, if audio input is a mircophone (deviceid=1 on my machine).

Has anyone experience recording audio from a modem (like a TAM does) ?

Any hint what to try, where to find information would be great

Thanks


Guenther

[William Bingham]

Vac

Virtual Audio Cables might be worth a try.

[Roger Garstang]

I used to do this with a little device I got at Radio Shack. It went inline with an actual phone line and output the audio which I could record through the aux input line. May not be what you want since it sounds like you want to talk using your PC soundcard too and it worked through an actual phone, but it will record the conversation on any device (tape, CD, PC, micro cassette/digital recorder, etc).

[Guest]

Great tip William, with virtual audio cable i got it working finally.
Many thanks !

Roger, i thought about that too, but you are right this is not what i want
thanks anyway.

I don´t know if this is the right place to ask such questions, because it
might be not possible to do this with power basic. Nevertheless i ask here
hoping someone can help.

The solution William suggested works, but it seems rather complicated to
me. The path of audio info, i want to record, goes like this:

modem hardware AD-PCM-Wave converter
-> modem driver (-> modem audio driver)
-> sm56hlpr.exe -> directsound -> soundcard

virtual audio cables must be configured as default audio output, then
it goes like this:

modem hardware AD-PCM-Wave converter
-> modem driver (-> modem audio driver)
-> sm56hlpr.exe -> directsound
-> virtual audio cable ->
-> my app

sm56hlpr.exe is a helper utility transferring audio from the
modem (audio) driver to directsound default audio output device.

So it should be possible to have it this way:

modem hardware AD-PCM-Wave converter
-> modem driver (-> modem audio driver)
-> my app

sm56hlpr.exe comunicates with smserial.sys (modem driver),
gets the audio info and routes it to directsound. So all i would have to
do is communicate with this driver myself, but this communication
cannot be established as expected. In control panel this modem (driver)
is listed as audio input wave device. But i cannot open it as wave device.
What am i doing wrong? Any suggestions?


Thanks,

Guenther

[Guest]

To end this topic, here is what i have done finally.

After some research with sm56hlpr.exe, i found out
the audio stream is not routed through sm56hlpr.exe.
sm56hlpr.exe communicates with the modem driver via
deviceiocontrol. If necessary the driver requests for
a handle (or pointer or whatever) from sm56hlpr.exe.
Sm56hlpr.exe initialises DirectX audio and passes this
handle to the driver which in return uses it, to send
audio data via KS interface.

No way to intercept audio data in sm56hlpr.exe

So i do the following:

set vitual audio cable as default audio output device,
by setting this registry entry

HKEY_CURRENT_USER\Software\Microsoft\Multimedia\Sound Mapper\playback

to "Virtual Cable 1", then start sm56hlpr.exe, send "ath1"
(initialze DirectX with the default audio output = virtual cable 1)
send "atz", restore the previous registry value.

Now i can connect to virtual audio cable using wave functions.
look for a sample program like "soundcapture" in forums to see
how this could be done.

Other running or later on started audio programs are not affected
and will work as expected.

Virtual audio cable was the tip, that really made it possible.


Thanks to all, special thanks to William


Guenther