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) 1996-2020 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 |
68 | |