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/**************************************************************************
copyright : (C) 2007 by Lukáš Lalinský
email : lalinsky@gmail.com
**************************************************************************/
/***************************************************************************
* 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., 51 Franklin Street, Fifth Floor, Boston, MA *
* 02110-1301 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 <tdebug.h>
#include <tstring.h>
#include "mp4file.h"
#include "mp4atom.h"
#include "mp4properties.h"
using namespace TagLib;
class MP4::Properties::PropertiesPrivate
{
public:
PropertiesPrivate() :
length(0),
bitrate(0),
sampleRate(0),
channels(0),
bitsPerSample(0),
encrypted(false),
codec(MP4::Properties::Unknown) {}
int length;
int bitrate;
int sampleRate;
int channels;
int bitsPerSample;
bool encrypted;
Codec codec;
};
////////////////////////////////////////////////////////////////////////////////
// public members
////////////////////////////////////////////////////////////////////////////////
MP4::Properties::Properties(File *file, MP4::Atoms *atoms, ReadStyle style) :
AudioProperties(style),
d(new PropertiesPrivate())
{
read(file, atoms);
}
MP4::Properties::~Properties()
{
delete d;
}
int
MP4::Properties::channels() const
{
return d->channels;
}
int
MP4::Properties::sampleRate() const
{
return d->sampleRate;
}
int
MP4::Properties::length() const
{
return lengthInSeconds();
}
int
MP4::Properties::lengthInSeconds() const
{
return d->length / 1000;
}
int
MP4::Properties::lengthInMilliseconds() const
{
return d->length;
}
int
MP4::Properties::bitrate() const
{
return d->bitrate;
}
int
MP4::Properties::bitsPerSample() const
{
return d->bitsPerSample;
}
bool
MP4::Properties::isEncrypted() const
{
return d->encrypted;
}
MP4::Properties::Codec
MP4::Properties::codec() const
{
return d->codec;
}
////////////////////////////////////////////////////////////////////////////////
// private members
////////////////////////////////////////////////////////////////////////////////
void
MP4::Properties::read(File *file, Atoms *atoms)
{
MP4::Atom *moov = atoms->find("moov");
if(!moov) {
debug("MP4: Atom 'moov' not found");
return;
}
MP4::Atom *trak = 0;
ByteVector data;
const MP4::AtomList trakList = moov->findall("trak");
for(MP4::AtomList::ConstIterator it = trakList.begin(); it != trakList.end(); ++it) {
trak = *it;
MP4::Atom *hdlr = trak->find("mdia", "hdlr");
if(!hdlr) {
debug("MP4: Atom 'trak.mdia.hdlr' not found");
return;
}
file->seek(hdlr->offset);
data = file->readBlock(hdlr->length);
if(data.containsAt("soun", 16)) {
break;
}
trak = 0;
}
if(!trak) {
debug("MP4: No audio tracks");
return;
}
MP4::Atom *mdhd = trak->find("mdia", "mdhd");
if(!mdhd) {
debug("MP4: Atom 'trak.mdia.mdhd' not found");
return;
}
file->seek(mdhd->offset);
data = file->readBlock(mdhd->length);
const unsigned int version = data[8];
long long unit;
long long length;
if(version == 1) {
if(data.size() < 36 + 8) {
debug("MP4: Atom 'trak.mdia.mdhd' is smaller than expected");
return;
}
unit = data.toUInt(28U);
length = data.toLongLong(32U);
}
else {
if(data.size() < 24 + 8) {
debug("MP4: Atom 'trak.mdia.mdhd' is smaller than expected");
return;
}
unit = data.toUInt(20U);
length = data.toUInt(24U);
}
if(unit > 0 && length > 0)
d->length = static_cast<int>(length * 1000.0 / unit + 0.5);
MP4::Atom *atom = trak->find("mdia", "minf", "stbl", "stsd");
if(!atom) {
return;
}
file->seek(atom->offset);
data = file->readBlock(atom->length);
if(data.containsAt("mp4a", 20)) {
d->codec = AAC;
d->channels = data.toShort(40U);
d->bitsPerSample = data.toShort(42U);
d->sampleRate = data.toUInt(46U);
if(data.containsAt("esds", 56) && data[64] == 0x03) {
unsigned int pos = 65;
if(data.containsAt("\x80\x80\x80", pos)) {
pos += 3;
}
pos += 4;
if(data[pos] == 0x04) {
pos += 1;
if(data.containsAt("\x80\x80\x80", pos)) {
pos += 3;
}
pos += 10;
d->bitrate = static_cast<int>((data.toUInt(pos) + 500) / 1000.0 + 0.5);
}
}
}
else if(data.containsAt("alac", 20)) {
if(atom->length == 88 && data.containsAt("alac", 56)) {
d->codec = ALAC;
d->bitsPerSample = data.at(69);
d->channels = data.at(73);
d->bitrate = static_cast<int>(data.toUInt(80U) / 1000.0 + 0.5);
d->sampleRate = data.toUInt(84U);
}
}
MP4::Atom *drms = atom->find("drms");
if(drms) {
d->encrypted = true;
}
}
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