get_bits.h

/* 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 3 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, see <http://www.gnu.org/licenses/>.
 *
 */
 
#ifndef IMAGE_CODECS_INDEO_GET_BITS_H
#define IMAGE_CODECS_INDEO_GET_BITS_H
 
#include "common/bitstream.h"
 
namespace Image {
namespace Indeo {
 
class GetBits : public Common::BitStreamMemory8LSB {
public:
    GetBits(const byte *dataPtr, uint32 dataSize) : Common::BitStreamMemory8LSB(new Common::BitStreamMemoryStream(dataPtr, dataSize), DisposeAfterUse::YES) {}
 
    int getBitsLeft() const { return size() - pos(); }
 
    template <int maxDepth, int bits>
    int getVLC2(int16 (*table)[2]) {
        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