source: 3DVCSoftware/trunk/source/Lib/TLibEncoder/NALwrite.cpp @ 1405

Last change on this file since 1405 was 1405, checked in by tech, 8 years ago

Merged HTM-16.1-dev@1404.

File size: 4.7 KB
Line 
1/* The copyright in this software is being made available under the BSD
2 * License, included below. This software may be subject to other third party
3 * and contributor rights, including patent rights, and no such rights are
4 * granted under this license.
5 *
6 * Copyright (c) 2010-2016, ITU/ISO/IEC
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions are met:
11 *
12 *  * Redistributions of source code must retain the above copyright notice,
13 *    this list of conditions and the following disclaimer.
14 *  * Redistributions in binary form must reproduce the above copyright notice,
15 *    this list of conditions and the following disclaimer in the documentation
16 *    and/or other materials provided with the distribution.
17 *  * Neither the name of the ITU/ISO/IEC nor the names of its contributors may
18 *    be used to endorse or promote products derived from this software without
19 *    specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
22 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS
25 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
31 * THE POSSIBILITY OF SUCH DAMAGE.
32 */
33
34#include <vector>
35#include <algorithm>
36#include <ostream>
37
38#include "TLibCommon/NAL.h"
39#include "TLibCommon/TComBitStream.h"
40#include "NALwrite.h"
41
42using namespace std;
43
44//! \ingroup TLibEncoder
45//! \{
46
47static const UChar emulation_prevention_three_byte[] = {3};
48
49Void writeNalUnitHeader(ostream& out, OutputNALUnit& nalu)       // nal_unit_header()
50{
51TComOutputBitstream bsNALUHeader;
52
53  bsNALUHeader.write(0,1);                    // forbidden_zero_bit
54  bsNALUHeader.write(nalu.m_nalUnitType, 6);  // nal_unit_type
55#if NH_MV
56  bsNALUHeader.write(nalu.m_nuhLayerId, 6);      // layerId       
57#else
58  bsNALUHeader.write(nalu.m_nuhLayerId, 6);   // nuh_layer_id
59#endif
60  bsNALUHeader.write(nalu.m_temporalId+1, 3); // nuh_temporal_id_plus1
61
62  out.write(reinterpret_cast<const TChar*>(bsNALUHeader.getByteStream()), bsNALUHeader.getByteStreamLength());
63}
64/**
65 * write nalu to bytestream out, performing RBSP anti startcode
66 * emulation as required.  nalu.m_RBSPayload must be byte aligned.
67 */
68Void write(ostream& out, OutputNALUnit& nalu)
69{
70  writeNalUnitHeader(out, nalu);
71  /* write out rsbp_byte's, inserting any required
72   * emulation_prevention_three_byte's */
73  /* 7.4.1 ...
74   * emulation_prevention_three_byte is a byte equal to 0x03. When an
75   * emulation_prevention_three_byte is present in the NAL unit, it shall be
76   * discarded by the decoding process.
77   * The last byte of the NAL unit shall not be equal to 0x00.
78   * Within the NAL unit, the following three-byte sequences shall not occur at
79   * any byte-aligned position:
80   *  - 0x000000
81   *  - 0x000001
82   *  - 0x000002
83   * Within the NAL unit, any four-byte sequence that starts with 0x000003
84   * other than the following sequences shall not occur at any byte-aligned
85   * position:
86   *  - 0x00000300
87   *  - 0x00000301
88   *  - 0x00000302
89   *  - 0x00000303
90   */
91  vector<uint8_t>& rbsp   = nalu.m_Bitstream.getFIFO();
92
93  vector<uint8_t> outputBuffer;
94  outputBuffer.resize(rbsp.size()*2+1); //there can never be enough emulation_prevention_three_bytes to require this much space
95  std::size_t outputAmount = 0;
96  Int         zeroCount    = 0;
97  for (vector<uint8_t>::iterator it = rbsp.begin(); it != rbsp.end(); it++)
98  {
99    const uint8_t v=(*it);
100    if (zeroCount==2 && v<=3)
101    {
102      outputBuffer[outputAmount++]=emulation_prevention_three_byte[0];
103      zeroCount=0;
104    }
105
106    if (v==0)
107    {
108      zeroCount++;
109    }
110    else
111    {
112      zeroCount=0;
113    }
114    outputBuffer[outputAmount++]=v;
115  }
116
117  /* 7.4.1.1
118   * ... when the last byte of the RBSP data is equal to 0x00 (which can
119   * only occur when the RBSP ends in a cabac_zero_word), a final byte equal
120   * to 0x03 is appended to the end of the data.
121   */
122  if (zeroCount>0)
123  {
124    outputBuffer[outputAmount++]=emulation_prevention_three_byte[0];
125  }
126  out.write(reinterpret_cast<const TChar*>(&(*outputBuffer.begin())), outputAmount);
127}
128
129//! \}
Note: See TracBrowser for help on using the repository browser.