summaryrefslogtreecommitdiffstats
path: root/dom/media/BitWriter.h
blob: 64e28c7ebc7c7bbe9cf9ebce26a8030780360621 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef BIT_WRITER_H_
#define BIT_WRITER_H_

#include "mozilla/RefPtr.h"

namespace mozilla {

class MediaByteBuffer;

class BitWriter {
 public:
  explicit BitWriter(MediaByteBuffer* aBuffer);
  virtual ~BitWriter();
  void WriteBits(uint64_t aValue, size_t aBits);
  void WriteBit(bool aValue) { WriteBits(aValue, 1); }
  void WriteU8(uint8_t aValue) { WriteBits(aValue, 8); }
  void WriteU32(uint32_t aValue) { WriteBits(aValue, 32); }
  void WriteU64(uint64_t aValue) { WriteBits(aValue, 64); }

  // Write unsigned integer into Exp-Golomb-coded. 2^32-2 at most
  void WriteUE(uint32_t aValue);
  // Write unsigned integer Little Endian Base 128 coded.
  void WriteULEB128(uint64_t aValue);

  // Write RBSP trailing bits.
  void CloseWithRbspTrailing();

  // Return the number of bits written so far;
  size_t BitCount() const { return mPosition * 8 + mBitIndex; }

 private:
  RefPtr<MediaByteBuffer> mBuffer;
  size_t mPosition = 0;
  uint8_t mBitIndex = 0;
};

}  // namespace mozilla

#endif  // BIT_WRITER_H_