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/*
* Copyright (c) 2004 MUSIC TECHNOLOGY GROUP (MTG)
* UNIVERSITAT POMPEU FABRA
*
*
* 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.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
// Welcome to the "FileInfo" example. In this example, we will see how we can
// check:
// + That a given file is readable by CLAM
// + Its header data
// + Its 'text' descriptors
// This header imports CLAM::AudioFile class interface
#include "AudioFile.hxx"
#include <iostream>
// To make this example minimally interesting, we will accept one parameter to
// the program, which will be the filename we wish to inspect
int main( int argc, char** argv )
{
if ( argc == 1 ) // No input file
{
std::cerr << "No input file" << std::endl;
std::cerr << "Usage: FileInfo <input file name>" << std::endl;
return -1;
}
else if ( argc > 2 ) // Too many parameters
{
std::cerr << "Too many parameters" << std::endl;
std::cerr << "Usage: FileInfo <input file name>" << std::endl;
return -1;
}
// Now we take argv[1] ( the second token in the command used to invoke this
// program ) as the 'File Location'
CLAM::AudioFileSource file;
file.OpenExisting( argv[1] );
// Once set the location, the AudioFile object internally does several things:
// + It checks that the file exists and is readable ( it conforms to one of
// the supported formats )
// + Extracts useful header data, such as sampling rate, number of channels, etc.
// + Extracts some textual meta-data that could be embedded in the file itself
// So first, let's check that the input file is readable
if ( !file.IsReadable() )
{
std::cerr << "Error: file " << file.GetLocation() << " cannot be opened ";
std::cerr << "or is encoded in an unrecognized format" << std::endl;
return -1;
}
// If it was readable now we can safely assume we can access its header
std::cout << "Filename: " << file.GetLocation() << std::endl;
// Now we print out the format it was encoded:
std::cout << "Format: " << file.GetHeader().GetFormat() << std::endl;
// The number of channels in the file
std::cout << "Channels: " << file.GetHeader().GetChannels() << std::endl;
// Its sample rate
std::cout << "Sample Rate: " << file.GetHeader().GetSampleRate() << " Hz" << std::endl;
// And its length. However this is not so straight-forward since we provide
// file duration in *milliseconds*. This might not be the best way ( we know ) but
// for now, CLAM sees times as milliseconds. We can try to convert it into something like
// hh:mm:ss
CLAM::TTime durationMs = file.GetHeader().GetLength();
CLAM::TTime numberSeconds = durationMs / 1000.;
CLAM::TTime numberMinutes = (int)(numberSeconds / 60.);
numberSeconds = numberSeconds - numberMinutes * 60.;
CLAM::TTime numberHours = int(numberMinutes / 60.);
numberMinutes = numberMinutes - numberHours * 60.;
// and now we print it formatted:
std::cout << "Length (hh:mm:ss): ";
std::cout << numberHours << ":" << numberMinutes << ":" << numberSeconds << std::endl;
// Finally, we can also access textual meta-data, if it was present in the file, of course.
// AudioFile's textual meta-data is stored in an AudioTextDescriptors object, that we
// can access as follows:
const CLAM::AudioTextDescriptors& txtDesc = file.GetTextDescriptors();
// For now, AudioTextDescriptors only can hold the following attributes:
// + Artist name
// + Title/Songname
// + Album/Movie/Show name
// + Track number ( in album )
// + Composer name
// + Performer name
//
// Obviously, it will be strange that all (or any) of these attributes are available, so we must be
// careful before accessing each attribute:
if ( txtDesc.HasArtist() )
std::cout << "Artist name: " << txtDesc.GetArtist() << std::endl;
if ( txtDesc.HasTitle() )
std::cout << "Title/Songname: " << txtDesc.GetTitle() << std::endl;
if ( txtDesc.HasAlbum() )
std::cout << "Album/Movie/Show name: " << txtDesc.GetAlbum() << std::endl;
if ( txtDesc.HasTrackNumber() )
std::cout << "Track number: " << txtDesc.GetTrackNumber() << std::endl;
if ( txtDesc.HasComposer() )
std::cout << "Composer name: " << txtDesc.GetComposer() << std::endl;
if ( txtDesc.HasPerformer() )
std::cout << "Performer name: " << txtDesc.GetPerformer() << std::endl;
// And that's all friends!
return 0;
}
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