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/***************************************************************************
copyright : (C) 2004 by Allan Sandfeld Jensen
email : kde@carewolf.org
***************************************************************************/
/***************************************************************************
* This library is free software; you can redistribute it and/or modify *
* it under the terms of the GNU Lesser General Public License version *
* 2.1 as published by the Free Software Foundation. *
* *
* 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 *
* *
* Alternatively, this file is available under the Mozilla Public *
* License Version 1.1. You may obtain a copy of the License at *
* http://www.mozilla.org/MPL/ *
***************************************************************************/
#include <tstring.h>
#include <tdebug.h>
#include <bitset>
#include "mpcproperties.h"
#include "mpcfile.h"
using namespace TagLib;
class MPC::Properties::PropertiesPrivate
{
public:
PropertiesPrivate(const ByteVector &d, long length, ReadStyle s) :
data(d),
streamLength(length),
style(s),
version(0),
length(0),
bitrate(0),
sampleRate(0),
channels(0) {}
ByteVector data;
long streamLength;
ReadStyle style;
int version;
int length;
int bitrate;
int sampleRate;
int channels;
};
////////////////////////////////////////////////////////////////////////////////
// public members
////////////////////////////////////////////////////////////////////////////////
MPC::Properties::Properties(const ByteVector &data, long streamLength, ReadStyle style) : AudioProperties(style)
{
d = new PropertiesPrivate(data, streamLength, style);
read();
}
MPC::Properties::~Properties()
{
delete d;
}
int MPC::Properties::length() const
{
return d->length;
}
int MPC::Properties::bitrate() const
{
return d->bitrate;
}
int MPC::Properties::sampleRate() const
{
return d->sampleRate;
}
int MPC::Properties::channels() const
{
return d->channels;
}
int MPC::Properties::mpcVersion() const
{
return d->version;
}
////////////////////////////////////////////////////////////////////////////////
// private members
////////////////////////////////////////////////////////////////////////////////
static const unsigned short sftable [4] = { 44100, 48000, 37800, 32000 };
void MPC::Properties::read()
{
if(!d->data.startsWith("MP+"))
return;
d->version = d->data[3] & 15;
unsigned int frames;
if(d->version >= 7) {
frames = d->data.mid(4, 4).toUInt(false);
std::bitset<32> flags = d->data.mid(8, 4).toUInt(false);
d->sampleRate = sftable[flags[17] * 2 + flags[16]];
d->channels = 2;
}
else {
uint headerData = d->data.mid(0, 4).toUInt(false);
d->bitrate = (headerData >> 23) & 0x01ff;
d->version = (headerData >> 11) & 0x03ff;
d->sampleRate = 44100;
d->channels = 2;
if(d->version >= 5)
frames = d->data.mid(4, 4).toUInt(false);
else
frames = d->data.mid(6, 2).toUInt(false);
}
uint samples = frames * 1152 - 576;
d->length = d->sampleRate > 0 ? (samples + (d->sampleRate / 2)) / d->sampleRate : 0;
if(!d->bitrate)
d->bitrate = d->length > 0 ? ((d->streamLength * 8L) / d->length) / 1000 : 0;
}
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