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/***************************************************************************
copyright : (C) 2015 by Tsuda Kageyu
email : tsuda.kageyu@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/ *
***************************************************************************/
#ifndef TAGLIB_MPEGUTILS_H
#define TAGLIB_MPEGUTILS_H
// THIS FILE IS NOT A PART OF THE TAGLIB API
#ifndef DO_NOT_DOCUMENT // tell Doxygen not to document this header
namespace TagLib
{
namespace MPEG
{
namespace
{
/*!
* MPEG frames can be recognized by the bit pattern 11111111 111, so the
* first byte is easy to check for, however checking to see if the second byte
* starts with \e 111 is a bit more tricky, hence these functions.
*
* \note This does not check the length of the vector, since this is an
* internal utility function.
*/
inline bool isFrameSync(const ByteVector &bytes, unsigned int offset = 0)
{
// 0xFF in the second byte is possible in theory, but it's very unlikely.
const unsigned char b1 = bytes[offset + 0];
const unsigned char b2 = bytes[offset + 1];
return (b1 == 0xFF && b2 != 0xFF && (b2 & 0xE0) == 0xE0);
}
}
}
}
#endif
#endif
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