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k3b/plugins/decoder/wave/k3bwavedecoder.cpp

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/*
*
* $Id: k3bwavedecoder.cpp 619556 2007-01-03 17:38:12Z trueg $
* Copyright (C) 2003 Sebastian Trueg <trueg@k3b.org>
*
* This file is part of the K3b project.
* Copyright (C) 1998-2007 Sebastian Trueg <trueg@k3b.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
* See the file "COPYING" for the exact licensing terms.
*/
#include <config.h>
#include "k3bwavedecoder.h"
#include <k3bpluginfactory.h>
#include <tqfile.h>
#include <tqcstring.h>
#include <kdebug.h>
#include <tdelocale.h>
K_EXPORT_COMPONENT_FACTORY( libk3bwavedecoder, K3bPluginFactory<K3bWaveDecoderFactory>( "libk3bwavedecoder" ) )
static unsigned short le_a_to_u_short( unsigned char* a ) {
return ((unsigned short)
((a[0] & 0xFF) |
(a[1] << 8 & 0xFF00)) );
}
static unsigned long le_a_to_u_long( unsigned char* a ) {
return ((unsigned long)
((a[0] & 0xFF) |
(a[1] << 8 & 0xFF00) |
(a[2] << 16 & 0xFF0000) |
(a[3] << 24 & 0xFF000000)) );
}
/**
* Returns the length of the wave file in bytes
* Otherwise 0 is returned.
* leave file seek pointer past WAV header.
*/
static unsigned long identifyWaveFile( TQFile* f, int* samplerate = 0, int* channels = 0, int* samplesize = 0 )
{
typedef struct {
unsigned char ckid[4];
unsigned char cksize[4];
} chunk_t;
typedef struct {
unsigned char wave[4];
} riff_chunk;
typedef struct {
unsigned char fmt_tag[2];
unsigned char channels[2];
unsigned char sample_rate[4];
unsigned char av_byte_rate[4];
unsigned char block_size[2];
unsigned char bits_per_sample[2];
} fmt_chunk;
static const char* WAV_RIFF_MAGIC = "RIFF"; // Magic for file format
static const char* WAV_WAVE_MAGIC = "WAVE"; // Magic for Waveform Audio
static const char* WAV_FMT_MAGIC = "fmt "; // Start of Waveform format
static const char* WAV_DATA_MAGIC = "data"; // Start of data chunk
chunk_t chunk;
riff_chunk riff;
fmt_chunk fmt;
// read riff chunk
if( f->readBlock( (char*)&chunk, sizeof(chunk) ) != sizeof(chunk) ) {
kdDebug() << "(K3bWaveDecoder) unable to read from " << f->name() << endl;
return 0;
}
if( tqstrncmp( (char*)chunk.ckid, WAV_RIFF_MAGIC, 4 ) ) {
kdDebug() << "(K3bWaveDecoder) " << f->name() << ": not a RIFF file." << endl;
return 0;
}
// read wave chunk
if( f->readBlock( (char*)&riff, sizeof(riff) ) != sizeof(riff) ) {
kdDebug() << "(K3bWaveDecoder) unable to read from " << f->name() << endl;
return 0;
}
if( tqstrncmp( (char*)riff.wave, WAV_WAVE_MAGIC, 4 ) ) {
kdDebug() << "(K3bWaveDecoder) " << f->name() << ": not a WAVE file." << endl;
return 0;
}
// read fmt chunk
if( f->readBlock( (char*)&chunk, sizeof(chunk) ) != sizeof(chunk) ) {
kdDebug() << "(K3bWaveDecoder) unable to read from " << f->name() << endl;
return 0;
}
if( tqstrncmp( (char*)chunk.ckid, WAV_FMT_MAGIC, 4 ) ) {
kdDebug() << "(K3bWaveDecoder) " << f->name() << ": could not find format chunk." << endl;
return 0;
}
if( f->readBlock( (char*)&fmt, sizeof(fmt) ) != sizeof(fmt) ) {
kdDebug() << "(K3bWaveDecoder) unable to read from " << f->name() << endl;
return 0;
}
if( le_a_to_u_short(fmt.fmt_tag) != 1 ||
le_a_to_u_short(fmt.channels) > 2 ||
( le_a_to_u_short(fmt.bits_per_sample) != 16 &&
le_a_to_u_short(fmt.bits_per_sample) != 8 ) ) {
kdDebug() << "(K3bWaveDecoder) " << f->name() << ": wrong format:" << endl
<< " format: " << le_a_to_u_short(fmt.fmt_tag) << endl
<< " channels: " << le_a_to_u_short(fmt.channels) << endl
<< " samplerate: " << le_a_to_u_long(fmt.sample_rate) << endl
<< " bits/sample: " << le_a_to_u_short(fmt.bits_per_sample) << endl;
return 0;
}
int sampleRate = le_a_to_u_long(fmt.sample_rate);
int ch = le_a_to_u_short(fmt.channels);
int sampleSize = le_a_to_u_short(fmt.bits_per_sample);;
if( samplerate )
*samplerate = sampleRate;
if( channels )
*channels = ch;
if( samplesize )
*samplesize = sampleSize;
// skip all other (unknown) format chunk fields
if( !f->at( f->at() + le_a_to_u_long(chunk.cksize) - sizeof(fmt) ) ) {
kdDebug() << "(K3bWaveDecoder) " << f->name() << ": could not seek in file." << endl;
return 0;
}
// find data chunk
bool foundData = false;
while( !foundData ) {
if( f->readBlock( (char*)&chunk, sizeof(chunk) ) != sizeof(chunk) ) {
kdDebug() << "(K3bWaveDecoder) unable to read from " << f->name() << endl;
return 0;
}
// skip chunk data of unknown chunk
if( tqstrncmp( (char*)chunk.ckid, WAV_DATA_MAGIC, 4 ) ) {
kdDebug() << "(K3bWaveDecoder) skipping chunk: " << (char*)chunk.ckid << endl;
if( !f->at( f->at() + le_a_to_u_long(chunk.cksize) ) ) {
kdDebug() << "(K3bWaveDecoder) " << f->name() << ": could not seek in file." << endl;
return 0;
}
}
else
foundData = true;
}
// found data chunk
unsigned long size = le_a_to_u_long(chunk.cksize);
if( f->at() + size > (unsigned long)f->size() ) {
kdDebug() << "(K3bWaveDecoder) " << f->name() << ": file length " << f->size()
<< " does not match length from WAVE header " << f->at() << " + " << size
<< " - using actual length." << endl;
size = (f->size() - f->at());
}
return size;
}
class K3bWaveDecoder::Private {
public:
Private()
: buffer(0),
bufferSize(0) {
}
TQFile* file;
long headerLength;
int sampleRate;
int channels;
int sampleSize;
unsigned long size;
unsigned long alreadyRead;
char* buffer;
int bufferSize;
};
K3bWaveDecoder::K3bWaveDecoder( TQObject* parent, const char* name )
: K3bAudioDecoder( parent, name )
{
d = new Private();
d->file = new TQFile();
}
K3bWaveDecoder::~K3bWaveDecoder()
{
delete d->file;
delete d;
}
int K3bWaveDecoder::decodeInternal( char* _data, int maxLen )
{
int read = 0;
maxLen = TQMIN( maxLen, (int)(d->size - d->alreadyRead) );
if( d->sampleSize == 16 ) {
read = d->file->readBlock( _data, maxLen );
if( read > 0 ) {
d->alreadyRead += read;
if( read % 2 > 0 ) {
kdDebug() << "(K3bWaveDecoder) data length is not a multiple of 2! Cutting data." << endl;
read -= 1;
}
// swap bytes
char buf;
for( int i = 0; i < read; i+=2 ) {
buf = _data[i];
_data[i] = _data[i+1];
_data[i+1] = buf;
}
}
}
else {
if( !d->buffer ) {
d->buffer = new char[maxLen/2];
d->bufferSize = maxLen/2;
}
read = d->file->readBlock( d->buffer, TQMIN(maxLen/2, d->bufferSize) );
d->alreadyRead += read;
// stretch samples to 16 bit
from8BitTo16BitBeSigned( d->buffer, _data, read );
read *= 2;
}
return read;
}
bool K3bWaveDecoder::analyseFileInternal( K3b::Msf& frames, int& samplerate, int& channels )
{
// handling wave files is very easy...
if( initDecoderInternal() ) {
//
// d->size is the number of bytes in the wave file
//
unsigned long size = d->size;
if( d->sampleRate != 44100 )
size = (int)((double)size * 44100.0 / (double)d->sampleRate);
if( d->sampleSize == 8 )
size *= 2;
if( d->channels == 1 )
size *= 2;
//
// we pad to a multiple of 2352 bytes
// (the actual padding of zero data will be done by the K3bAudioDecoder class)
//
if( (size%2352) > 0 )
size = (size/2352) + 1;
else
size = size/2352;
frames = size;
samplerate = d->sampleRate;
channels = d->channels;
return true;
}
else
return false;
}
bool K3bWaveDecoder::initDecoderInternal()
{
cleanup();
d->file->setName( filename() );
if( !d->file->open( IO_ReadOnly ) ) {
kdDebug() << "(K3bWaveDecoder) could not open file." << endl;
return false;
}
// skip the header
d->size = identifyWaveFile( d->file, &d->sampleRate, &d->channels, &d->sampleSize );
if( d->size <= 0 ) {
kdDebug() << "(K3bWaveDecoder) no supported wave file." << endl;
cleanup();
return false;
}
d->headerLength = d->file->at();
d->alreadyRead = 0;
return true;
}
bool K3bWaveDecoder::seekInternal( const K3b::Msf& pos )
{
return( d->file->at( d->headerLength + (pos.totalFrames()*2352) ) );
}
void K3bWaveDecoder::cleanup()
{
if( d->file->isOpen() )
d->file->close();
}
TQString K3bWaveDecoder::fileType() const
{
return i18n("WAVE");
}
TQStringList K3bWaveDecoder::supportedTechnicalInfos() const
{
return TQStringList::split( ";",
i18n("Channels") + ";" +
i18n("Sampling Rate") + ";" +
i18n("Sample Size") );
}
TQString K3bWaveDecoder::technicalInfo( const TQString& name ) const
{
if( name == i18n("Channels") )
return TQString::number(d->channels);
else if( name == i18n("Sampling Rate") )
return i18n("%1 Hz").arg(d->sampleRate);
else if( name == i18n("Sample Size") )
return i18n("%1 bits").arg(d->sampleSize);
else
return TQString();
}
K3bWaveDecoderFactory::K3bWaveDecoderFactory( TQObject* parent, const char* name )
: K3bAudioDecoderFactory( parent, name )
{
}
K3bWaveDecoderFactory::~K3bWaveDecoderFactory()
{
}
K3bAudioDecoder* K3bWaveDecoderFactory::createDecoder( TQObject* parent,
const char* name ) const
{
return new K3bWaveDecoder( parent, name );
}
bool K3bWaveDecoderFactory::canDecode( const KURL& url )
{
TQFile f( url.path() );
if( !f.open( IO_ReadOnly ) ) {
kdDebug() << "(K3bWaveDecoder) could not open file " << url.path() << endl;
return false;
}
return (identifyWaveFile( &f ) > 0);
}
#include "k3bwavedecoder.moc"