SetMP3(string inputFile)
{
// Get information about inputFile,
// use to give beConfig initial
// values:
LibsndfileWrapper.SF_INFO soundInfo =
new LibsndfileWrapper.SF_INFO();
LibsndfileWrapper libSndFile = new LibsndfileWrapper();
libSndFile.GetSoundFileType(inputFile, ref soundInfo);
beConfig = new LameWrapper.BE_CONFIG(soundInfo);
}
CheckSoundFormat(string inputFile)
{
// Verify existence of inputFilenm, throw
// exception if not exist
if (!System.IO.File.Exists(inputFile))
{
throw new FileNotFoundException(
"Cannot find file " + inputFile);
}
// Check for non-MP3 sound file
LibsndfileWrapper libSndFile = new LibsndfileWrapper();
LibsndfileWrapper.SF_INFO soundInfo =
new LibsndfileWrapper.SF_INFO();
int i = libSndFile.GetSoundFileType(inputFile, ref soundInfo);
// First check to see if it's an audio
// format !MP3. Then check for MP3.
// If no valid format found, throw
// exception.
if (soundInfo.format != 0)
{
return((soundFormat)soundInfo.format);
}
else
{
MP3Check verifyMP3 = new MP3Check(inputFile, 2);
if (!verifyMP3.Check())
{
throw new Exception("Cannot determine sound file type: " +
inputFile);
}
else
{
return(soundFormat.MP3);
}
}
}
Convert(string inputFile, int convertFrom,
string outputFile, int convertTo, Reporter updateStatus)
{
// Verify existence of inputFilenm, throw
// exception if not exist
if (!System.IO.File.Exists(inputFile))
{
throw new FileNotFoundException(
"Cannot find file " + inputFile);
}
// Input file information
// (Set input file size)
FileInfo fi = new FileInfo(inputFile);
int soundFileSize = (int)fi.Length;
// Select conversion routines based
// on input/output file types
// If outfile = MP3 then use LameWriter
// to encode, using the settings in the
// structure mp3set (essentially the LHV1
// struct from LameWrapper):
if ((soundFormat)convertTo == soundFormat.MP3)
{
// File to convert from must be WAV
if (!((convertFrom >= (int)soundFormat.WAV) &&
(convertFrom < (int)soundFormat.AIFF)))
{
throw new Exception(
"Cannot encode to MP3 directly from this format ("
+ convertFrom + "). Convert to WAV first");
}
LameWriter mp3Writer = null;
// Instantiate LameWriter object
// with output filename
if (beConfig == null)
{
// Use default MP3 output settings
mp3Writer = new LameWriter(
new FileStream(outputFile, FileMode.Create),
inputFile);
}
else
{
// Use custom settings
mp3Writer = new LameWriter(
new FileStream(outputFile, FileMode.Create),
inputFile,
beConfig);
}
// open input file for binary reading
Stream s = new FileStream(inputFile,
FileMode.Open, FileAccess.Read);
BinaryReader br = new BinaryReader(s);
// setup byte buffer -- use mp3Writer.sampleSize
// to ensure correct buffer size
byte[] wavBuffer = new byte[mp3Writer.sampleSize];
// skip WAV header
s.Seek(LameWrapper.SKIP_WAV_HEADER, SeekOrigin.Begin);
// write mp3 file
int index = 0;
int processedBytes = 0;
while
((index = br.Read(wavBuffer, 0, mp3Writer.sampleSize)) > 0)
{
processedBytes += mp3Writer.sampleSize;
// Send to callback:
updateStatus(soundFileSize, processedBytes, this);
// Check for kill
if (this.killSwitch)
{
break;
}
mp3Writer.Write(wavBuffer, 0, index);
}
// Finish up
mp3Writer.Close();
mp3Writer.WriteTags(outputFile);
}
// Assume libsndfile conversion:
else
{
// Check and make sure we are not
// trying to decode MP3->WAV
// Instantiate object
LibsndfileWrapper libSndFile = new LibsndfileWrapper();
LibsndfileWrapper.SF_INFO soundInfo =
new LibsndfileWrapper.SF_INFO();
// Calculate total frames to convert
int i = libSndFile.GetSoundFileType(inputFile, ref soundInfo);
// Each frame is 16bit:
long totalFrames = soundInfo.frames * 2;
// Initialize
libSndFile.Initialize(inputFile,
outputFile, (LibsndfileWrapper.soundFormat)convertTo);
// The main decoding loop
long readCount;
long readIndex = 0;
while ((readCount = libSndFile.Read()) > 0)
{
readIndex += readCount;
// Send update to delegate.
// Note that this is in
// libsndfile specific frames
// rather than in actual bytes.
//
// readIndex / totalFrames =
// percentage complete
updateStatus((int)totalFrames, (int)readIndex, this);
// Check for kill
if (this.killSwitch)
{
break;
}
// Write to file
libSndFile.Write();
}
// Close up shop
libSndFile.Close();
}
}
BE_CONFIG(LibsndfileWrapper.SF_INFO soundInfo) :
this(soundInfo, 128)
{
}
BE_CONFIG(LibsndfileWrapper.SF_INFO soundInfo, uint mp3bitrate)
{
this.dwConfig = BE_CONFIG_LAME;
this.union = new struct_un(soundInfo, mp3bitrate);
}
struct_un(LibsndfileWrapper.SF_INFO soundInfo, uint mp3bitrate)
{
lhv1 = new LHV1(soundInfo, mp3bitrate);
}
LHV1(LibsndfileWrapper.SF_INFO soundInfo, uint mp3bitrate)
{
// Error if not WAV, 16bit
if (soundInfo.format !=
((int)LibsndfileWrapper.soundFormat.SF_FORMAT_WAV |
(int)LibsndfileWrapper.soundFormat.SF_FORMAT_PCM_16))
{
throw new ArgumentOutOfRangeException(
"format",
"Only WAV 16 bit uncompressed supported. " +
"You gave format " + soundInfo.format);
}
dwStructVersion = 1;
dwStructSize = (uint)Marshal.SizeOf(typeof(BE_CONFIG));
// Handle sample rate
switch (soundInfo.samplerate)
{
case 16000:
case 22050:
case 24000:
dwMpegVersion = MPEG2;
break;
case 32000:
case 44100:
case 48000:
dwMpegVersion = MPEG1;
break;
default:
throw new ArgumentOutOfRangeException(
"format", "Sample rate " +
soundInfo.samplerate + " not supported");
}
dwSampleRate = (uint)soundInfo.samplerate;
dwReSampleRate = 0;
// Handle channels
switch (soundInfo.channels)
{
case 1:
mpgmode = mpeg_mode.MONO;
break;
case 2:
mpgmode = mpeg_mode.STEREO;
break;
default:
throw new ArgumentOutOfRangeException(
"format",
"Invalid number of channels:" + soundInfo.channels);
}
// Handle bit rate
switch (mp3bitrate)
{
case 32:
case 40:
case 48:
case 56:
case 64:
case 80:
case 96:
case 112:
case 128:
// Allowed bit rates in MPEG1 and MPEG2:
case 160:
break;
case 192:
case 224:
case 256:
// Allowed only in MPEG1:
case 320:
if (dwMpegVersion != MPEG1)
{
throw new ArgumentOutOfRangeException(
"mp3bitrate", "Incompatible bit rate:" + mp3bitrate);
}
break;
case 8:
case 16:
case 24:
// Allowed only in MPEG2:
case 144:
if (dwMpegVersion != MPEG2)
{
throw new ArgumentOutOfRangeException(
"mp3bitrate", "Incompatible bit rate:" + mp3bitrate);
}
break;
default:
throw new ArgumentOutOfRangeException(
"mp3bitrate", "Can't support bit rate");
}
// MINIMUM BIT RATE:
dwBitrate = mp3bitrate;
// QUALITY PRESET SETTING:
nPreset = LAME_QUALITY_PRESET.LQP_NORMAL_QUALITY;
// USE DEFAULT PSYCHOACOUSTIC MODEL:
dwPsyModel = 0;
// NO EMPHASIS TURNED ON:
dwEmphasis = 0;
// SET ORIGINAL FLAG:
bOriginal = 1;
bWriteVBRHeader = 0;
// No bit reservoir:
bNoRes = 0;
bCopyright = 0;
bCRC = 0;
bEnableVBR = 0;
bPrivate = 0;
bStrictIso = 0;
dwMaxBitrate = 0;
dwVbrAbr_bps = 0;
nQuality = 0;
nVbrMethod = VBRMETHOD.VBR_METHOD_NONE;
nVBRQuality = 0;
}
