blob: d6aeff559b6c3f0f48d95dbcfa49ca92510fdb2b (
plain) (
blame)
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
|
/*
* The contents of this file are subject to the Mozilla Public
* License Version 1.1 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS
* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
* implied. See the License for the specific language governing
* rights and limitations under the License.
*
* The Original Code is MPEG4IP.
*
* The Initial Developer of the Original Code is Cisco Systems Inc.
* Portions created by Cisco Systems Inc. are
* Copyright (C) Cisco Systems Inc. 2001. All Rights Reserved.
*
* Contributor(s):
* Dave Mackie dmackie@cisco.com
*/
#include "mp4common.h"
MP4StscAtom::MP4StscAtom()
: MP4Atom("stsc")
{
AddVersionAndFlags();
MP4Integer32Property* pCount =
new MP4Integer32Property("entryCount");
AddProperty(pCount);
MP4TableProperty* pTable = new MP4TableProperty("entries", pCount);
AddProperty(pTable);
pTable->AddProperty(
new MP4Integer32Property("firstChunk"));
pTable->AddProperty(
new MP4Integer32Property("samplesPerChunk"));
pTable->AddProperty(
new MP4Integer32Property("sampleDescriptionIndex"));
// As an optimization we add an implicit property to this table,
// "firstSample" that corresponds to the first sample of the firstChunk
MP4Integer32Property* pSample =
new MP4Integer32Property("firstSample");
pSample->SetImplicit();
pTable->AddProperty(pSample);
}
void MP4StscAtom::Read()
{
// Read as usual
MP4Atom::Read();
// Compute the firstSample values for later use
u_int32_t count =
((MP4Integer32Property*)m_pProperties[2])->GetValue();
MP4Integer32Property* pFirstChunk = (MP4Integer32Property*)
((MP4TableProperty*)m_pProperties[3])->GetProperty(0);
MP4Integer32Property* pSamplesPerChunk = (MP4Integer32Property*)
((MP4TableProperty*)m_pProperties[3])->GetProperty(1);
MP4Integer32Property* pFirstSample = (MP4Integer32Property*)
((MP4TableProperty*)m_pProperties[3])->GetProperty(3);
MP4SampleId sampleId = 1;
for (u_int32_t i = 0; i < count; i++) {
pFirstSample->SetValue(sampleId, i);
if (i < count - 1) {
sampleId +=
(pFirstChunk->GetValue(i+1) - pFirstChunk->GetValue(i))
* pSamplesPerChunk->GetValue(i);
}
}
}
|
