DMO.zip_DMO

//------------------------------------------------------------------------------ // File: Wave.c // // Desc: DirectShow sample code - Wave library routines. // // Copyright (c) Microsoft Corporation. All rights reserved. //------------------------------------------------------------------------------ /*========================================================================== * * This file is used for loading/saving waves, and reading and * writing waves in smaller blocks. * Uses WaveOpenFile, WaveReadFile and WaveCloseReadFile for * single block access to reading wave files. * Uses WaveCreateFile, WaveWriteFile, WaveCloseWriteFile for * single block access for writing wave files. * Uses WaveLoadFile to load a whole wave file into memory. * Uses WaveSaveFile to save a whole wave file into memory. * ***************************************************************************/ #pragma warning(disable:4100) // Disable C4100: unreferenced formal parameter #pragma warning(disable:4213) // Disable C4213: cast on lvalue #pragma warning(disable:4115) // Disable C4115: (from VC6.0 header rpsasync.h) #include <windows.h> #include <mmsystem.h> #include "wave.h" #include "debug.h" #include "windowsx.h" #pragma warning(default:4115) // Reset to default behavior for C4115 /* ROUTINES */ /* -------------------------------------------------------*/ /* This function will open a wave input file and prepare it for reading, * so the data can be easily * read with WaveReadFile. Returns 0 if successful, the error code if not. * pszFileName - Input filename to load. * phmmioIn - Pointer to handle which will be used * for further mmio routines. * ppwfxInfo - Ptr to ptr to WaveFormatEx structure * with all info about the file. * */ int WaveOpenFile( TCHAR*pszFileName, // (IN) HMMIO *phmmioIn, // (OUT) WAVEFORMATEX **ppwfxInfo, // (OUT) MMCKINFO *pckInRIFF // (OUT) ) { HMMIO hmmioIn; MMCKINFO ckIn; // chunk info. for general use. PCMWAVEFORMAT pcmWaveFormat; // Temp PCM structure to load in. WORD cbExtraAlloc; // Extra bytes for waveformatex int nError; // Return value. // Initialization *ppwfxInfo = NULL; nError = 0; hmmioIn = NULL; if ((hmmioIn = mmioOpen(pszFileName, NULL, MMIO_ALLOCBUF | MMIO_READ)) == NULL) { nError = ER_CANNOTOPEN; goto ERROR_READING_WAVE; } if ((nError = (int)mmioDescend(hmmioIn, pckInRIFF, NULL, 0)) != 0) { goto ERROR_READING_WAVE; } if ((pckInRIFF->ckid != FOURCC_RIFF) || (pckInRIFF->fccType != mmioFOURCC('W', 'A', 'V', 'E'))) { nError = ER_NOTWAVEFILE; goto ERROR_READING_WAVE; } /* Search the input file for for the 'fmt ' chunk. */ ckIn.ckid = mmioFOURCC('f', 'm', 't', ' '); if ((nError = (int)mmioDescend(hmmioIn, &ckIn, pckInRIFF, MMIO_FINDCHUNK)) != 0) { goto ERROR_READING_WAVE; } /* Expect the 'fmt' chunk to be at least as large as <PCMWAVEFORMAT>; * if there are extra parameters at the end, we'll ignore them */ if (ckIn.cksize < (long) sizeof(PCMWAVEFORMAT)) { nError = ER_NOTWAVEFILE; goto ERROR_READING_WAVE; } /* Read the 'fmt ' chunk into <pcmWaveFormat>.*/ if (mmioRead(hmmioIn, (HPSTR) &pcmWaveFormat, (long) sizeof(pcmWaveFormat)) != (long) sizeof(pcmWaveFormat)) { nError = ER_CANNOTREAD; goto ERROR_READING_WAVE; } // Allocate the waveformatex, but if its not pcm // format, read the next word, and thats how many extra // bytes to allocate. if (pcmWaveFormat.wf.wFormatTag == WAVE_FORMAT_PCM) cbExtraAlloc = 0; else { // Read in length of extra bytes. if (mmioRead(hmmioIn, (HPSTR) &cbExtraAlloc, (long) sizeof(cbExtraAlloc)) != (long) sizeof(cbExtraAlloc)) { nError = ER_CANNOTREAD; goto ERROR_READING_WAVE; } } // Now allocate that waveformatex structure. if ((*ppwfxInfo = GlobalAlloc(GMEM_FIXED, sizeof(WAVEFORMATEX)+cbExtraAlloc)) == NULL) { nError = ER_MEM; goto ERROR_READING_WAVE; } // Copy the bytes from the pcm structure to the waveformatex structure memcpy(*ppwfxInfo, &pcmWaveFormat, sizeof(pcmWaveFormat)); (*ppwfxInfo)->cbSize = cbExtraAlloc; // Read those extra bytes into the structure, if cbExtraAlloc != 0. if (cbExtraAlloc != 0) { if (mmioRead(hmmioIn, (HPSTR) (((BYTE*)&((*ppwfxInfo)->cbSize))+sizeof(cbExtraAlloc)), (long) (cbExtraAlloc)) != (long) (cbExtraAlloc)) { nError = ER_NOTWAVEFILE; goto ERROR_READING_WAVE; } } /* Ascend the input file out of the 'fmt ' chunk. */ if ((nError = mmioAscend(hmmioIn, &ckIn, 0)) != 0) { goto ERROR_READING_WAVE; } goto TEMPCLEANUP; ERROR_READING_WAVE: if (*ppwfxInfo != NULL) { GlobalFree(*ppwfxInfo); *ppwfxInfo = NULL; } if (hmmioIn != NULL) { mmioClose(hmmioIn, 0); hmmioIn = NULL; } TEMPCLEANUP: *phmmioIn = hmmioIn; return(nError); } /* This routine has to be called before WaveReadFile as it searchs for the chunk to descend into for reading, that is, the 'data' chunk. For simplicity, this used to be in the open routine, but was taken out and moved to a separate routine so there was more control on the chunks that are before the data chunk, such as 'fact', etc... */ int WaveStartDataRead( HMMIO *phmmioIn, MMCKINFO *pckIn, MMCKINFO *pckInRIFF ) { int nError=0; // Perform a seek... if ((nError = mmioSeek(*phmmioIn, pckInRIFF->dwDataOffset + sizeof(FOURCC), SEEK_SET)) == -1) { // ASSERT(FALSE); } nError = 0; // Search the input file for for the 'data' chunk. pckIn->ckid = mmioFOURCC('d', 'a', 't', 'a'); nError = mmioDescend(*phmmioIn, pckIn, pckInRIFF, MMIO_FINDCHUNK); return(nError); } /* This will read wave data from the wave file. Makre sure we're descended into the data chunk, else this will fail bigtime! hmmioIn - Handle to mmio. cbRead - # of bytes to read. pbDest - Destination buffer to put bytes. cbActualRead- # of bytes actually read. */ int WaveReadFile( HMMIO hmmioIn, // IN UINT cbRead, // IN BYTE *pbDest, // IN MMCKINFO *pckIn, // IN. UINT *cbActualRead // OUT. ) { MMIOINFO mmioinfoIn; // current status of <hmmioIn> int nError=0; UINT cT, cbDataIn; if ((nError = mmioGetInfo(hmmioIn, &mmioinfoIn, 0)) != 0) { goto ERROR_CANNOT_READ; } cbDataIn = cbRead; if (cbDataIn > pckIn->cksize) cbDataIn = pckIn->cksize; pckIn->cksize -= cbDataIn; for (cT = 0; cT < cbDataIn; cT++) { /* Copy the bytes from the io to the buffer. */ if (mmioinfoIn.pchNext == mmioinfoIn.pchEndRead) { if ((nError = mmioAdvance(hmmioIn, &mmioinfoIn, MMIO_READ)) != 0) {