Can we use function acmStreamConvert() to decode an mp3 file?

Can we use function acmStreamConvert() to decode an mp3 file or any other kind of compressed audio format?
If it can? How to do that?
Thanks a lot^_^.

depends whether you have an mp3 codec (or whatever compressed audio format is in question) installed on your system or not.

Originally Posted by juhnu

depends whether you have an mp3 codec (or whatever compressed audio format is in question) installed on your system or not.

I can get the driver id of the mp3 codec, but the most important is that I did not how to fill the WAVEFORMATEX struct. Which function can be called to get the information such as the sample rate? Thanks a lot^_^.

why don't you just encode or convert a file (the plain old soundrecorder can do this), load the WAVEFORMATEX structure and take a look what they put into the fields?

As far as I remember (I decoded mp3's using the ACM-services) everything was pretty obvious (e.g. bitrate directly translated into nAvgBytesPerSec ect.).

also - this could be helpful:

http://64.233.183.104/search?q=cache...EGLAYER3&hl=it

Originally Posted by Nils Pipenbrinck

why don't you just encode or convert a file (the plain old soundrecorder can do this), load the WAVEFORMATEX structure and take a look what they put into the fields?

As far as I remember (I decoded mp3's using the ACM-services) everything was pretty obvious (e.g. bitrate directly translated into nAvgBytesPerSec ect.).

also - this could be helpful:

http://64.233.183.104/search?q=cache...EGLAYER3&hl=it

My mission is to decode some compressed wave format file and play it by direct sound. I does not have the original uncompressed wave file, and I want to play the compressed wave file just like direct show do. But if I use direct show, I cound not controll some 3D parameters such as position. So I had to use the ACM-services to decode such file and play it with direct sound. But since the file format is unknown, I want to know that how to choose the right driver and how to fill the WAVEFORMATEX just like direct show do? Thanks a lot^_^

I can not open the url you gave me, can you paste the code in the url to me? Or send to my email? My email box is ho19@hotmail.com. Thanks a lot^_^.

#include <windows.h>
#include <stdio.h>
#include <assert.h>
#include <mmreg.h>
#include <msacm.h>

#define MP3_BLOCK_SIZE 522
#define SOURCE_MP3 "C:\\audiograbber\\At The Club Last Night\\At_The_Club_Last_Night_-_Haven't_You_Heard.mp3"
#define OUTPUT_PCM_FILE "c:\\dump.pcm"

int g_mp3Drivers = 0;

BOOL CALLBACK acmDriverEnumCallback( HACMDRIVERID hadid, DWORD dwInstance, DWORD fdwSupport ){
  if( fdwSupport & ACMDRIVERDETAILS_SUPPORTF_CODEC ) {
    MMRESULT mmr;

    ACMDRIVERDETAILS details;
    details.cbStruct = sizeof(ACMDRIVERDETAILS);
    mmr = acmDriverDetails( hadid, &details, 0 );

    HACMDRIVER driver;
    mmr = acmDriverOpen( &driver, hadid, 0 );

    int i;
    for(i = 0; i < details.cFormatTags; i++ ){
      ACMFORMATTAGDETAILS fmtDetails;
      ZeroMemory( &fmtDetails, sizeof(fmtDetails) );
      fmtDetails.cbStruct = sizeof(ACMFORMATTAGDETAILS);
      fmtDetails.dwFormatTagIndex = i;
      mmr = acmFormatTagDetails( driver, &fmtDetails, ACM_FORMATTAGDETAILSF_INDEX );
      if( fmtDetails.dwFormatTag == WAVE_FORMAT_MPEGLAYER3 ){
	OutputDebugString( L"Found an MP3-capable ACM codec: " );
	OutputDebugString( details.szLongName );
	OutputDebugString( L"\n" );
	g_mp3Drivers++;
      }
    }
    mmr = acmDriverClose( driver, 0 );
  }
  return true;
}

HACMSTREAM g_mp3stream = NULL;



convertMP3(){
  
  MMRESULT mmr;
  
  // try to find an MP3 codec
  acmDriverEnum( acmDriverEnumCallback, 0, 0 );
  if(g_mp3Drivers == 0){
    OutputDebugString( L"No MP3 decoders found!\n" );
    return E_FAIL;
  }
  
  // find the biggest format size
  DWORD maxFormatSize = 0;
  mmr = acmMetrics( NULL, ACM_METRIC_MAX_SIZE_FORMAT, &maxFormatSize );
  
  // define desired output format
  LPWAVEFORMATEX waveFormat = (LPWAVEFORMATEX) LocalAlloc( LPTR, maxFormatSize );
  waveFormat->wFormatTag = WAVE_FORMAT_PCM;
  waveFormat->nChannels = 2; // stereo
  waveFormat->nSamplesPerSec = 44100; // 44.1kHz
  waveFormat->wBitsPerSample = 16; // 16 bits
  waveFormat->nBlockAlign = 4; // 4 bytes of data at a time are useful (1 sample)
  waveFormat->nAvgBytesPerSec = 4 * 44100; // byte-rate
  waveFormat->cbSize = 0; // no more data to follow
  
  
  // define MP3 input format
  LPMPEGLAYER3WAVEFORMAT mp3format = (LPMPEGLAYER3WAVEFORMAT) LocalAlloc( LPTR, maxFormatSize );
  mp3format->wfx.cbSize = MPEGLAYER3_WFX_EXTRA_BYTES;
  mp3format->wfx.wFormatTag = WAVE_FORMAT_MPEGLAYER3;
  mp3format->wfx.nChannels = 2;
  mp3format->wfx.nAvgBytesPerSec = 128 * (1024 / 8);  // not really used but must be one of 64, 96, 112, 128, 160kbps
  mp3format->wfx.wBitsPerSample = 0;                  // MUST BE ZERO
  mp3format->wfx.nBlockAlign = 1;                     // MUST BE ONE
  mp3format->wfx.nSamplesPerSec = 44100;              // 44.1kHz
  mp3format->fdwFlags = MPEGLAYER3_FLAG_PADDING_OFF;
  mp3format->nBlockSize = MP3_BLOCK_SIZE;             // voodoo value #1
  mp3format->nFramesPerBlock = 1;                     // MUST BE ONE
  mp3format->nCodecDelay = 1393;                      // voodoo value #2
  mp3format->wID = MPEGLAYER3_ID_MPEG;
  
  g_mp3stream = NULL;
  mmr = acmStreamOpen( &g_mp3stream,               // open an ACM conversion stream
  		     NULL,                       // querying all ACM drivers
  		     (LPWAVEFORMATEX) mp3format, // converting from MP3
  		     waveFormat,                 // to WAV
  		     NULL,                       // with no filter
  		     0,                          // or async callbacks
  		     0,                          // (and no data for the callback)
  		     0                           // and no flags
  		     );
  
  LocalFree( mp3format );
  LocalFree( waveFormat );
  
  switch( mmr ) {
   case MMSYSERR_NOERROR:
     break; // success!
   case MMSYSERR_INVALPARAM:
     assert( !"Invalid parameters passed to acmStreamOpen" );
     return E_FAIL;
   case ACMERR_NOTPOSSIBLE:
     assert( !"No ACM filter found capable of decoding MP3" );
     return E_FAIL;
   default:
     assert( !"Some error opening ACM decoding stream!" );
     return E_FAIL;
  }
  
  // MP3 stream converter opened correctly
  // now, let's open a file, read in a bunch of MP3 data, and convert it!
  
  // open file
  FILE *fpIn = fopen( SOURCE_MP3, "rb" );
  if( fpIn == NULL ){
    assert( !"can't open MP3 file!" );
    return E_FAIL;
  }
  
  // find out how big the decompressed buffer will be
  unsigned long rawbufsize = 0;
  mmr = acmStreamSize( g_mp3stream, MP3_BLOCK_SIZE, &rawbufsize, ACM_STREAMSIZEF_SOURCE );
  assert( mmr == 0 );
  assert( rawbufsize > 0 );
  
  // allocate our I/O buffers
  LPBYTE mp3buf = (LPBYTE) LocalAlloc( LPTR, MP3_BLOCK_SIZE );
  LPBYTE rawbuf = (LPBYTE) LocalAlloc( LPTR, rawbufsize );
  
  // prepare the decoder
  ACMSTREAMHEADER mp3streamHead;
  ZeroMemory( &mp3streamHead, sizeof(ACMSTREAMHEADER ) );
  mp3streamHead.cbStruct = sizeof(ACMSTREAMHEADER );
  mp3streamHead.pbSrc = mp3buf;
  mp3streamHead.cbSrcLength = MP3_BLOCK_SIZE;
  mp3streamHead.pbDst = rawbuf;
  mp3streamHead.cbDstLength = rawbufsize;
  mmr = acmStreamPrepareHeader( g_mp3stream, &mp3streamHead, 0 );
  assert( mmr == 0 );
  
  // let's dump this data off to disk (for debug checking!)
  FILE *fpOut = fopen( OUTPUT_PCM_FILE, "wb" );
  if( fpOut == NULL ){
    assert( !"can't output output PCM!" );
    return E_FAIL;
  }
  
  while(1) {
    // suck in some MP3 data
    int count = fread( mp3buf, 1, MP3_BLOCK_SIZE, fpIn );
    if( count != MP3_BLOCK_SIZE )
      break;
  
    // convert the data
    mmr = acmStreamConvert( g_mp3stream, &mp3streamHead, ACM_STREAMCONVERTF_BLOCKALIGN );
    assert( mmr == 0 );
  
    // write the decoded PCM to disk
    count = fwrite( rawbuf, 1, mp3streamHead.cbDstLengthUsed, fpOut );
    assert( count == mp3streamHead.cbDstLengthUsed );
  };
  
  // clean up after yourself like a good little boy
  fclose( fpIn );
  fclose( fpOut );
  mmr = acmStreamUnprepareHeader( g_mp3stream, &mp3streamHead, 0 );
  assert( mmr == 0 );
  LocalFree(rawbuf);
  LocalFree(mp3buf);
  mmr = acmStreamClose( g_mp3stream, 0 );
  assert( mmr == 0 );
  
  return S_OK;
}