blob: 288abf390f649d4af6e37a7b7230e33e44f72c4c (
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
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
|
/*
* $Id$
*
* (C) 2006-2010 see AUTHORS
*
* This file is part of mplayerc.
*
* Mplayerc 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 3 of the License, or
* (at your option) any later version.
*
* Mplayerc 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, see <http://www.gnu.org/licenses/>.
*
*/
#include "stdafx.h"
#include "H264Nalu.h"
void CH264Nalu::SetBuffer(BYTE* pBuffer, int nSize, int nNALSize)
{
m_pBuffer = pBuffer;
m_nSize = nSize;
m_nNALSize = nNALSize;
m_nCurPos = 0;
m_nNextRTP = 0;
m_nNALStartPos = 0;
m_nNALDataPos = 0;
}
bool CH264Nalu::MoveToNextStartcode()
{
int nBuffEnd = (m_nNextRTP > 0) ? min(m_nNextRTP, m_nSize - 4) : m_nSize - 4;
for(int i = m_nCurPos; i < nBuffEnd; i++)
{
if((*((DWORD*)(m_pBuffer + i)) & 0x00FFFFFF) == 0x00010000)
{
// Find next AnnexB Nal
m_nCurPos = i;
return true;
}
}
if((m_nNALSize != 0) && (m_nNextRTP < m_nSize))
{
m_nCurPos = m_nNextRTP;
return true;
}
m_nCurPos = m_nSize;
return false;
}
bool CH264Nalu::ReadNext()
{
if(m_nCurPos >= m_nSize) return false;
if((m_nNALSize != 0) && (m_nCurPos == m_nNextRTP))
{
// RTP Nalu type : (XX XX) XX XX NAL..., with XX XX XX XX or XX XX equal to NAL size
m_nNALStartPos = m_nCurPos;
m_nNALDataPos = m_nCurPos + m_nNALSize;
int nTemp = 0;
for(int i = 0; i < m_nNALSize; i++)
{
nTemp = (nTemp << 8) + m_pBuffer[m_nCurPos++];
}
m_nNextRTP += nTemp + m_nNALSize;
MoveToNextStartcode();
}
else
{
// Remove trailing bits
while(m_pBuffer[m_nCurPos] == 0x00 && ((*((DWORD*)(m_pBuffer + m_nCurPos)) & 0x00FFFFFF) != 0x00010000))
m_nCurPos++;
// AnnexB Nalu : 00 00 01 NAL...
m_nNALStartPos = m_nCurPos;
m_nCurPos += 3;
m_nNALDataPos = m_nCurPos;
MoveToNextStartcode();
}
forbidden_bit = (m_pBuffer[m_nNALDataPos] >> 7) & 1;
nal_reference_idc = (m_pBuffer[m_nNALDataPos] >> 5) & 3;
nal_unit_type = (NALU_TYPE)(m_pBuffer[m_nNALDataPos] & 0x1f);
return true;
}
|
