Hi All,
For long now have tried to get Python bindings and none is there.
jlgm suggested me to try ctypes and I dived in. But there are few examples on using ctypes for new bees like me.
I tried to take lame_enc.dll (The file made me to learn ctypes :) ) as sample to play with. The sad thing is, I find only C/C++ examples of the DLL and I failed to translate them.
Here is the example:
/*
* LAME DLL Sample Code.
*
* Copyright (c) 2000 A.L. Faber
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include <windows.h>
#include <stdio.h>
#include <io.h>
#include <fcntl.h>
#include <sys/stat.h>
#include "BladeMP3EncDLL.h"
BEINITSTREAM beInitStream=NULL;
BEENCODECHUNK beEncodeChunk=NULL;
BEDEINITSTREAM beDeinitStream=NULL;
BECLOSESTREAM beCloseStream=NULL;
BEVERSION beVersion=NULL;
BEWRITEVBRHEADER beWriteVBRHeader=NULL;
// Main program
int main(int argc, char *argv[])
{
HINSTANCE hDLL =NULL;
FILE* pFileIn =NULL;
FILE* pFileOut =NULL;
BE_VERSION Version ={0,};
BE_CONFIG beConfig ={0,};
CHAR strFileIn[255] ={'0',};
CHAR strFileOut[255] ={'0',};
DWORD dwSamples =0;
DWORD dwMP3Buffer =0;
HBE_STREAM hbeStream =0;
BE_ERR err =0;
PBYTE pMP3Buffer =NULL;
PSHORT pWAVBuffer =NULL;
// check number of arguments
if(argc != 2)
{
fprintf(stderr,"Usage: %s <filename.wav>\n", argv[0]);
fprintf(stderr,"Descr: Short demo to show how to use the lame_enc.dll library file\n");
fprintf(stderr,"Note : WAV file is assumed to to have the following parameters\n");
fprintf(stderr," : 44100 Hz, stereo, 16 Bits per sample\n");
return -1;
}
// Setup the file names
strcpy(strFileIn ,argv[1]);
strcpy(strFileOut,argv[1]);
// Add mp3 extention
strcat(strFileOut,".mp3");
// Load lame_enc.dll library (Make sure though that you set the
// project/settings/debug Working Directory correctly, otherwhise the DLL can't be loaded
#ifdef _MSC_VER
hDLL = LoadLibrary(".\\Debug\\lame_enc.dll");
#ifdef _DEBUG
hDLL = LoadLibrary(".\\Debug\\lame_enc.dll");
#else
hDLL = LoadLibrary(".\\Release\\lame_enc.dll");
if ( NULL == hDLL )
{
hDLL = LoadLibrary(".\\Release_NASM\\lame_enc.dll");
}
#endif /* _DEBUG */
#else
/*
Don't worry about dll location.
MSVC is the only compiler that creates
.\Release\ or .\Debug\ directories.
*/
hDLL = LoadLibrary("lame_enc.dll");
#endif /* _MSC_VER */
if( NULL == hDLL )
{
fprintf(stderr,"Error loading lame_enc.DLL");
return -1;
}
// Get Interface functions from the DLL
beInitStream = (BEINITSTREAM) GetProcAddress(hDLL, TEXT_BEINITSTREAM);
beEncodeChunk = (BEENCODECHUNK) GetProcAddress(hDLL, TEXT_BEENCODECHUNK);
beDeinitStream = (BEDEINITSTREAM) GetProcAddress(hDLL, TEXT_BEDEINITSTREAM);
beCloseStream = (BECLOSESTREAM) GetProcAddress(hDLL, TEXT_BECLOSESTREAM);
beVersion = (BEVERSION) GetProcAddress(hDLL, TEXT_BEVERSION);
beWriteVBRHeader= (BEWRITEVBRHEADER) GetProcAddress(hDLL,TEXT_BEWRITEVBRHEADER);
// Check if all interfaces are present
if(!beInitStream || !beEncodeChunk || !beDeinitStream || !beCloseStream || !beVersion || !beWriteVBRHeader)
{
printf("Unable to get LAME interfaces");
return -1;
}
// Get the version number
beVersion( &Version );
printf(
"lame_enc.dll version %u.%02u (%u/%u/%u)\n"
"lame_enc Engine %u.%02u\n"
"lame_enc homepage at %s\n\n",
Version.byDLLMajorVersion, Version.byDLLMinorVersion,
Version.byDay, Version.byMonth, Version.wYear,
Version.byMajorVersion, Version.byMinorVersion,
Version.zHomepage);
// Try to open the WAV file, be sure to open it as a binary file!
pFileIn = fopen( strFileIn, "rb" );
// Check file open result
if(pFileIn == NULL)
{
fprintf(stderr,"Error opening %s", argv[1]);
return -1;
}
// Open MP3 file
pFileOut= fopen(strFileOut,"wb+");
// Check file open result
if(pFileOut == NULL)
{
fprintf(stderr,"Error creating file %s", strFileOut);
return -1;
}
memset(&beConfig,0,sizeof(beConfig)); // clear all fields
// use the LAME config structure
beConfig.dwConfig = BE_CONFIG_LAME;
// this are the default settings for testcase.wav
beConfig.format.LHV1.dwStructVersion = 1;
beConfig.format.LHV1.dwStructSize = sizeof(beConfig);
beConfig.format.LHV1.dwSampleRate = 44100; // INPUT FREQUENCY
beConfig.format.LHV1.dwReSampleRate = 0; // DON"T RESAMPLE
beConfig.format.LHV1.nMode = BE_MP3_MODE_JSTEREO; // OUTPUT IN STREO
beConfig.format.LHV1.dwBitrate = 128; // MINIMUM BIT RATE
beConfig.format.LHV1.nPreset = LQP_HIGH_QUALITY; // QUALITY PRESET SETTING
beConfig.format.LHV1.dwMpegVersion = MPEG1; // MPEG VERSION (I or II)
beConfig.format.LHV1.dwPsyModel = 0; // USE DEFAULT PSYCHOACOUSTIC MODEL
beConfig.format.LHV1.dwEmphasis = 0; // NO EMPHASIS TURNED ON
beConfig.format.LHV1.bOriginal = TRUE; // SET ORIGINAL FLAG
// beConfig.format.LHV1.dwMaxBitrate = 320; // MAXIMUM BIT RATE
// beConfig.format.LHV1.bCRC = TRUE; // INSERT CRC
// beConfig.format.LHV1.bCopyright = TRUE; // SET COPYRIGHT FLAG
// beConfig.format.LHV1.bPrivate = TRUE; // SET PRIVATE FLAG
// beConfig.format.LHV1.bWriteVBRHeader = TRUE; // YES, WRITE THE XING VBR HEADER
// beConfig.format.LHV1.bEnableVBR = TRUE; // USE VBR
// beConfig.format.LHV1.nVBRQuality = 5; // SET VBR QUALITY
beConfig.format.LHV1.bNoRes = TRUE; // No Bit resorvoir
// Preset Test
// beConfig.format.LHV1.nPreset = LQP_PHONE;
// Init the MP3 Stream
err = beInitStream(&beConfig, &dwSamples, &dwMP3Buffer, &hbeStream);
// Check result
if(err != BE_ERR_SUCCESSFUL)
{
fprintf(stderr,"Error opening encoding stream (%lu)", err);
return -1;
}
// Allocate MP3 buffer
pMP3Buffer = new BYTE[dwMP3Buffer];
// Allocate WAV buffer
pWAVBuffer = new SHORT[dwSamples];
// Check if Buffer are allocated properly
if(!pMP3Buffer || !pWAVBuffer)
{
printf("Out of memory");
return -1;
}
DWORD dwRead=0;
DWORD dwWrite=0;
DWORD dwDone=0;
DWORD dwFileSize=0;
// Seek to end of file
fseek(pFileIn,0,SEEK_END);
// Get the file size
dwFileSize=ftell(pFileIn);
// Seek back to start of WAV file,
// but skip the first 44 bytes, since that's the WAV header
fseek(pFileIn,44,SEEK_SET);
// Convert All PCM samples
while ( (dwRead=fread(pWAVBuffer,sizeof(SHORT),dwSamples,pFileIn)) >0 )
{
// Encode samples
err = beEncodeChunk(hbeStream, dwRead, pWAVBuffer, pMP3Buffer, &dwWrite);
// Check result
if(err != BE_ERR_SUCCESSFUL)
{
beCloseStream(hbeStream);
fprintf(stderr,"beEncodeChunk() failed (%lu)", err);
return -1;
}
// write dwWrite bytes that are returned in tehe pMP3Buffer to disk
if(fwrite(pMP3Buffer,1,dwWrite,pFileOut) != dwWrite)
{
fprintf(stderr,"Output file write error");
return -1;
}
dwDone += dwRead*sizeof(SHORT);
printf("Done: %0.2f%% \r", 100 * (float)dwDone/(float)(dwFileSize));
}
// Deinit the stream
err = beDeinitStream(hbeStream, pMP3Buffer, &dwWrite);
// Check result
if(err != BE_ERR_SUCCESSFUL)
{
beCloseStream(hbeStream);
fprintf(stderr,"beExitStream failed (%lu)", err);
return -1;
}
// Are there any bytes returned from the DeInit call?
// If so, write them to disk
if(dwWrite)
{
if( fwrite( pMP3Buffer, 1, dwWrite, pFileOut ) != dwWrite )
{
fprintf(stderr,"Output file write error");
return -1;
}
}
// close the MP3 Stream
beCloseStream( hbeStream );
// Delete WAV buffer
delete [] pWAVBuffer;
// Delete MP3 Buffer
delete [] pMP3Buffer;
// Close input file
fclose( pFileIn );
// Close output file
fclose( pFileOut );
// Write the VBR Tag
beWriteVBRHeader( strFileOut );
// Were done, return OK result
return 0;
}and here is my trial; I failed to finish
import ctypes as ct
import os, sys
lame = ct.cdll.lame_enc
#start playing around
#Configure the LAME encoder the to do the conversion.
#use lame configuration structure
lame.beConfig.dwConfig = lame.BE_CONFIG_LAME
# this are the default settings for testcase.wav
lame.beConfig.format.LHV1.dwStructVersion = 1
lame.beConfig.format.LHV1.dwStructSize = sizeof(lame.beConfig)
lame.beConfig.format.LHV1.dwSampleRate = 44100 # INPUT FREQUENCY
lame.beConfig.format.LHV1.dwReSampleRate = 0 #DON"T RESAMPLE
lame.beConfig.format.LHV1.nMode = BE_MP3_MODE_JSTEREO #OUTPUT IN STREO
lame.beConfig.format.LHV1.dwBitrate = 128 #MINIMUM BIT RATE
lame.beConfig.format.LHV1.nPreset = LQP_HIGH_QUALITY #QUALITY PRESET SETTING
lame.beConfig.format.LHV1.dwMpegVersion = MPEG1 # MPEG VERSION (I or II)
lame.beConfig.format.LHV1.dwPsyModel = 0 #USE DEFAULT PSYCHOACOUSTIC MODEL
lame.beConfig.format.LHV1.dwEmphasis = 0 #NO EMPHASIS TURNED ON
lame.beConfig.format.LHV1.bOriginal = TRUE #SET ORIGINAL FLAG
#init mp3 stream
try:
mp3 = beInitStream(beConfig, dwSamples, dwMP3Buffer, hbeStream)
except:
print "Error: Cannot open encoding stream "
sys.exit(True)
#failed to go on due to lack of C/C++ knowledgeand here is TCL example:
http://wiki.tcl.tk/14289
and another CPP example:
http://www.creative-urge.com/ljpics/main.cpp
Please need help :S