live
BitVector.hh
Go to the documentation of this file.
1 /**********
2 This library is free software; you can redistribute it and/or modify it under
3 the terms of the GNU Lesser General Public License as published by the
4 Free Software Foundation; either version 3 of the License, or (at your
5 option) any later version. (See <http://www.gnu.org/copyleft/lesser.html>.)
6 
7 This library is distributed in the hope that it will be useful, but WITHOUT
8 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
9 FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for
10 more details.
11 
12 You should have received a copy of the GNU Lesser General Public License
13 along with this library; if not, write to the Free Software Foundation, Inc.,
14 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
15 **********/
16 // "liveMedia"
17 // Copyright (c) 1996-2022 Live Networks, Inc. All rights reserved.
18 // Bit Vector data structure
19 // C++ header
20 
21 #ifndef _BIT_VECTOR_HH
22 #define _BIT_VECTOR_HH
23 
24 #ifndef _BOOLEAN_HH
25 #include "Boolean.hh"
26 #endif
27 
28 class BitVector {
29 public:
30  BitVector(unsigned char* baseBytePtr,
31  unsigned baseBitOffset,
32  unsigned totNumBits);
33 
34  void setup(unsigned char* baseBytePtr,
35  unsigned baseBitOffset,
36  unsigned totNumBits);
37 
38  void putBits(unsigned from, unsigned numBits); // "numBits" <= 32
39  void put1Bit(unsigned bit);
40 
41  unsigned getBits(unsigned numBits); // "numBits" <= 32
42  unsigned get1Bit();
43  Boolean get1BitBoolean() { return get1Bit() != 0; }
44 
45  void skipBits(unsigned numBits);
46 
47  unsigned curBitIndex() const { return fCurBitIndex; }
48  unsigned totNumBits() const { return fTotNumBits; }
49  unsigned numBitsRemaining() const { return fTotNumBits - fCurBitIndex; }
50 
51  unsigned get_expGolomb();
52  // Returns the value of the next bits, assuming that they were encoded using an exponential-Golomb code of order 0
53  int get_expGolombSigned(); // signed version of the above
54 
55 private:
56  unsigned char* fBaseBytePtr;
57  unsigned fBaseBitOffset;
58  unsigned fTotNumBits;
59  unsigned fCurBitIndex;
60 };
61 
62 // A general bit copy operation:
63 void shiftBits(unsigned char* toBasePtr, unsigned toBitOffset,
64  unsigned char const* fromBasePtr, unsigned fromBitOffset,
65  unsigned numBits);
66 
67 #endif
void shiftBits(unsigned char *toBasePtr, unsigned toBitOffset, unsigned char const *fromBasePtr, unsigned fromBitOffset, unsigned numBits)
unsigned char Boolean
Definition: Boolean.hh:25
Boolean get1BitBoolean()
Definition: BitVector.hh:43
unsigned fCurBitIndex
Definition: BitVector.hh:59
unsigned get_expGolomb()
int get_expGolombSigned()
unsigned char * fBaseBytePtr
Definition: BitVector.hh:56
unsigned get1Bit()
BitVector(unsigned char *baseBytePtr, unsigned baseBitOffset, unsigned totNumBits)
unsigned fTotNumBits
Definition: BitVector.hh:58
void setup(unsigned char *baseBytePtr, unsigned baseBitOffset, unsigned totNumBits)
void skipBits(unsigned numBits)
unsigned numBitsRemaining() const
Definition: BitVector.hh:49
unsigned fBaseBitOffset
Definition: BitVector.hh:57
void putBits(unsigned from, unsigned numBits)
unsigned totNumBits() const
Definition: BitVector.hh:48
unsigned getBits(unsigned numBits)
unsigned curBitIndex() const
Definition: BitVector.hh:47
void put1Bit(unsigned bit)