sound.cpp

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// Media.cpp: implementation of the CSound class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "Multimedia.h"
#include "Media.h"
#include "string.h"

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

Media::CMedia()
{
	m_nDeviceID = 1;
	m_nElementID = 0;
	dwResult = 0;
	mciPlayParms.dwFrom = 0;
	closed = stopped = true;
	paused = false;
}

CSound::~CMedia()
{

}

DWORD CMedia::OpenDevice(LPCSTR pFileName,LPCSTR pFileExt)
{
	if(!closed)
	{
		CloseDevice();
		closed = true;
		m_nDeviceID = 1;
	}
	if(paused)
		paused = false;
	if (m_nDeviceID)
    {
		if(strcmp(pFileExt,"WAV") == 0 || strcmp(pFileExt,"wav") == 0)
		{
			mciOpenParms.lpstrDeviceType = "waveaudio";
			type = WAVE;
		}
		else if(strcmp(pFileExt,"MID") == 0 || strcmp(pFileExt,"mid") == 0)
		{
			mciOpenParms.lpstrDeviceType="sequencer";
			type = MIDI;
		}
		else if(strcmp(pFileExt,"CD") == 0 || strcmp(pFileExt,"cd") == 0)
		{
			mciOpenParms.lpstrDeviceType = "cdaudio";
			type = CD;
		}
		else if(strcmp(pFileExt,"AVI") == 0 || strcmp(pFileExt,"avi") == 0)
		{
			mciOpenParms.lpstrDeviceType = "avivideo";
			type = AVI;
		}

		//open the sound device
		mciOpenParms.wDeviceID = 0;
		mciOpenParms.lpstrElementName = pFileName;
		dwResult = mciSendCommand(NULL, MCI_OPEN,  MCI_WAIT|MCI_OPEN_TYPE|
		 MCI_OPEN_ELEMENT,(DWORD)(LPMCI_OPEN_PARMS)&mciOpenParms);
        //save device identifier,will use eith other MCI commands
		m_nDeviceID = mciOpenParms.wDeviceID;
		//display error message if failed 
		if(dwResult)
			DisplayErrorMsg(dwResult);
		else
		{
			stopped = closed =false;
		}
	}
		//return result of MCI operation
	return dwResult;
}

void CSound::DisplayErrorMsg(DWORD dwError)
{
	//check if there was an error
    if(dwError)
    {
		//character string that contains error message
		char szErrorMsg[MAXERRORLENGTH];
		//retrieve string associated error message
		if(!mciGetErrorString(dwError,szErrorMsg,sizeof(szErrorMsg)))
			strcpy(szErrorMsg,"Unknown Error");
		//display error string in message box
		AfxMessageBox(szErrorMsg);
    }
}

DWORD CSound::Play(CWnd* pWnd,LPCSTR pFileName)
{
		m_nElementID=mciOpenParms.wDeviceID;
		//instruct device to play file
		if(paused && type == WAVE)
		{
			dwResult = mciSendCommand(m_nDeviceID,MCI_RESUME,MCI_WAIT,
				(DWORD) (LPMCI_GENERIC_PARMS) &mciGenericParms);
			paused = false;
		}
		else
			dwResult = mciSendCommand(m_nDeviceID,MCI_PLAY,
			MCI_FROM,(DWORD)(LPMCI_PLAY_PARMS)&mciPlayParms);
		//display error and close element if failed
		if(dwResult)
        {
			DisplayErrorMsg(dwResult);
			Stop();
			stopped = true;
		}
		else
			stopped = false;
	//return result of MCI operation
		return dwResult;
}

DWORD CSound::Stop()
{
	//close if element is currently open
	if(m_nDeviceID)
	{
		dwResult = mciSendCommand(m_nDeviceID,MCI_STOP,
			MCI_WAIT,(DWORD) (LPMCI_GENERIC_PARMS) &mciStopParms);
		//display error message if failed
		if(dwResult)
			DisplayErrorMsg(dwResult);
		//set identifier to closed state
		else
			m_nDeviceID=0;
	}
	stopped = true;
	return dwResult;
}

DWORD CSound::CloseDevice()
{
	//close if currently open
	if(m_nDeviceID && !stopped)
	{
		//close the MCI device
		dwResult=mciSendCommand(m_nDeviceID,MCI_CLOSE,MCI_WAIT,NULL);
		//display error message if failed
		if(dwResult)
			DisplayErrorMsg(dwResult);
		//set identifier to close state
		else 
			m_nDeviceID=0;
	}
	//return result of MCI operation
	closed = true;
	return dwResult;
}

DWORD CSound::Pause()
{
	if(m_nDeviceID)
	{
		dwResult = mciSendCommand (m_nDeviceID, 
		MCI_PAUSE, MCI_WAIT,(DWORD)(LPMCI_GENERIC_PARMS) &mciGenericParms);
		if(dwResult)
		{
			DisplayErrorMsg(dwResult);
			return dwResult;
		}
	}
	paused = true;
	return dwResult;
}

DWORD CSound::BeginRecord()
{
	if(m_nDeviceID)
	{
		dwResult = mciSendCommand (m_nDeviceID, MCI_RECORD, 
			NULL, (DWORD)(LPMCI_RECORD_PARMS)&mciRecordParms);
		if(dwResult)
			DisplayErrorMsg(dwResult);
	}
	return dwResult;
}

DWORD CSound::SaveRecord(LPCSTR pFilename)
{
	if(m_nDeviceID)
	{
		mciSaveParms.lpfilename = pFilename;
		dwResult = mciSendCommand (m_nDeviceID, MCI_SAVE, 
			MCI_SAVE_FILE | MCI_WAIT,(DWORD)(LPMCI_SAVE_PARMS) &mciSaveParms);
		if(dwResult)
			DisplayErrorMsg(dwResult);
	}
	return dwResult;
}