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/***************************************************************************
copyright : (C) 2005 by Brian Nickel
email : brian.nickel@gmail.com
based on : xingheader.cpp from TagLib
***************************************************************************/
/***************************************************************************
* 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 *
***************************************************************************/
using System.Collections;
using System;
namespace TagLib.Mpeg
{
public class XingHeader
{
//////////////////////////////////////////////////////////////////////////
// private properties
//////////////////////////////////////////////////////////////////////////
private uint frames;
private uint size;
private bool valid;
//////////////////////////////////////////////////////////////////////////
// public methods
//////////////////////////////////////////////////////////////////////////
public XingHeader (ByteVector data)
{
frames = 0;
size = 0;
valid = false;
Parse (data);
}
//////////////////////////////////////////////////////////////////////////
// public properties
//////////////////////////////////////////////////////////////////////////
public bool IsValid {get {return valid;}}
public uint TotalFrames {get {return frames;}}
public uint TotalSize {get {return size;}}
//////////////////////////////////////////////////////////////////////////
// public static methods
//////////////////////////////////////////////////////////////////////////
public static int XingHeaderOffset (Version v, ChannelMode c)
{
if (v == Version.Version1)
{
if (c == ChannelMode.SingleChannel)
return 0x15;
else
return 0x24;
}
else
{
if (c == ChannelMode.SingleChannel)
return 0x0D;
else
return 0x15;
}
}
//////////////////////////////////////////////////////////////////////////
// private methods
//////////////////////////////////////////////////////////////////////////
private void Parse (ByteVector data)
{
// Check to see if a valid Xing header is available.
if(!data.StartsWith ("Xing"))
return;
// If the XingHeader doesn't contain the number of frames and the total stream
// info it's invalid.
if((data [7] & 0x02) == 0)
{
Debugger.Debug ("MPEG::XingHeader::parse() -- Xing header doesn't contain the total number of frames.");
return;
}
if((data[7] & 0x04) == 0)
{
Debugger.Debug ("MPEG::XingHeader::parse() -- Xing header doesn't contain the total stream size.");
return;
}
frames = data.Mid (8, 4).ToUInt ();
size = data.Mid (12, 4).ToUInt ();
valid = true;
}
}
}
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