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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.
*
*/
#include "common/scummsys.h"
/* Intel Indeo 4 bitstream reader
*
* Original copyright note:
* Copyright (c) 2004 Michael Niedermayer
*/
#ifndef IMAGE_CODECS_INDEO_GET_BITS_H
#define IMAGE_CODECS_INDEO_GET_BITS_H
#include "common/scummsys.h"
#include "common/stream.h"
#include "common/types.h"
namespace Image {
namespace Indeo {
#define AV_INPUT_BUFFER_PADDING_SIZE 32
/**
* Intel Indeo Bitstream reader
*/
class GetBits {
private:
const byte *_buffer;
uint _index;
uint _sizeInBits;
uint _sizeInBitsPlus8;
public:
/**
* Constructor
* @param buffer Bitstream buffer, must be AV_INPUT_BUFFER_PADDING_SIZE bytes
* larger than the actual read bits because some optimized bitstream
* readers read 32 or 64 bit at once and could read over the end
* @param bit_size the size of the buffer in bits
* @return 0 on success, AVERROR_INVALIDDATA if the buffer_size would overflow.
*/
GetBits(const byte *buffer, size_t totalBits);
/**
* Copy constructor
*/
GetBits(const GetBits &src);
/**
* Returns the number of bits read
*/
uint getBitsCount() const { return _index; }
/**
* The number of bits left
*/
int getBitsLeft() const { return _sizeInBits - _index; }
void skipBitsLong(uint n) { _index += n; }
/**
* Read MPEG-1 dc-style VLC (sign bit + mantissa with no MSB).
* if MSB not set it is negative
* @param n length in bits
*/
int getXbits(int n);
/**
* Returns the next n bits, and does sign extension
*/
int getSbits(int n);
/**
* Read 1-25 bits.
*/
uint getBits(int n);
/**
* Read 0-25 bits.
*/
int getBitsZ(int n);
uint getBitsLE(int n);
/**
* Show 1-25 bits.
* Returns the data without updating the index
*/
uint showBits(int n);
/**
* Skips a specified number of bits
*/
void skipBits(int n);
/**
* Returns the next bit
*/
uint getBits1();
/**
* Shows the next following bit
*/
uint showBits1();
/**
* Skips the next bit
*/
void skipBits1();
/**
* Read 0-32 bits.
*/
uint getBitsLong(int n);
/**
* Read 0-64 bits.
*/
uint64 getBits64(int n);
/**
* Read 0-32 bits as a signed integer.
*/
int getSbitsLong(int n);
/**
* Show 0-32 bits.
*/
uint showBitsLong(int n);
int checkMarker(void *logctx, const char *msg);
/**
* Parse a VLC code.
* @param bits is the number of bits which will be read at once, must be
* identical to nb_bits in init_vlc()
* @param max_depth is the number of times bits bits must be read to completely
* read the longest vlc code
* = (max_vlc_length + bits - 1) / bits
*/
int getVLC2(int16 (*table)[2], int bits, int maxDepth);
int decode012();
int decode210();
int skip1stop8dataBits();
const byte *alignGetBits();
};
} // End of namespace Indeo
} // End of namespace Image
#endif
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