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/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
#ifndef IMAGE_CODECS_INDEO_GET_BITS_H
#define IMAGE_CODECS_INDEO_GET_BITS_H
#include "common/bitstream.h"
namespace Image {
namespace Indeo {
/**
* Intel Indeo Bitstream reader
*/
class GetBits : public Common::BitStreamMemory8LSB {
public:
/**
* Constructor
* @param stream Source stream to reader from
* @param disposeAfterUse Whether to destroy stream in destructor
*/
GetBits(const uint8 *ptr, uint32 size) : Common::BitStreamMemory8LSB(new Common::BitStreamMemoryStream(ptr, size), DisposeAfterUse::YES) {}
/**
* The number of bits left
*/
int getBitsLeft() const { return size() - pos(); }
/**
* Parse a VLC code.
* @param bits is the number of bits which will be read at once, must be
* identical to nbBits in init_vlc()
* @param maxDepth is the number of times bits bits must be read to completely
* read the longest vlc code
* = (max_vlc_length + bits - 1) / bits
*/
template <int maxDepth>
int getVLC2(int16 (*table)[2], int bits) {
int code;
int n, nbBits;
unsigned int index;
index = peekBits(bits);
code = table[index][0];
n = table[index][1];
if (maxDepth > 1 && n < 0) {
skip(bits);
nbBits = -n;
index = peekBits(nbBits) + code;
code = table[index][0];
n = table[index][1];
if (maxDepth > 2 && n < 0) {
skip(nbBits);
nbBits = -n;
index = peekBits(nbBits) + code;
code = table[index][0];
n = table[index][1];
}
}
skip(n);
return code;
}
};
} // End of namespace Indeo
} // End of namespace Image
#endif
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