1 /*****************************************************************
2 |
3 | AP4 - sidx Atoms
4 |
5 | Copyright 2002-2014 Axiomatic Systems, LLC
6 |
7 |
8 | This file is part of Bento4/AP4 (MP4 Atom Processing Library).
9 |
10 | Unless you have obtained Bento4 under a difference license,
11 | this version of Bento4 is Bento4|GPL.
12 | Bento4|GPL is free software; you can redistribute it and/or modify
13 | it under the terms of the GNU General Public License as published by
14 | the Free Software Foundation; either version 2, or (at your option)
15 | any later version.
16 |
17 | Bento4|GPL is distributed in the hope that it will be useful,
18 | but WITHOUT ANY WARRANTY; without even the implied warranty of
19 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 | GNU General Public License for more details.
21 |
22 | You should have received a copy of the GNU General Public License
23 | along with Bento4|GPL; see the file COPYING. If not, write to the
24 | Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA
25 | 02111-1307, USA.
26 |
27 ****************************************************************/
28
29 /*----------------------------------------------------------------------
30 | includes
31 +---------------------------------------------------------------------*/
32 #include "Ap4SidxAtom.h"
33 #include "Ap4Utils.h"
34
35 /*----------------------------------------------------------------------
36 | dynamic cast support
37 +---------------------------------------------------------------------*/
AP4_DEFINE_DYNAMIC_CAST_ANCHOR(AP4_SidxAtom)38 AP4_DEFINE_DYNAMIC_CAST_ANCHOR(AP4_SidxAtom)
39
40
41 /*----------------------------------------------------------------------
42 | AP4_SidxAtom::Create
43 +---------------------------------------------------------------------*/
44 AP4_SidxAtom*
45 AP4_SidxAtom::Create(AP4_Size size, AP4_ByteStream& stream)
46 {
47 AP4_UI08 version;
48 AP4_UI32 flags;
49 if (size < AP4_FULL_ATOM_HEADER_SIZE) return NULL;
50 if (AP4_FAILED(AP4_Atom::ReadFullHeader(stream, version, flags))) return NULL;
51 if (version > 1) return NULL;
52 return new AP4_SidxAtom(size, version, flags, stream);
53 }
54
55 /*----------------------------------------------------------------------
56 | AP4_SidxAtom::AP4_SidxAtom
57 +---------------------------------------------------------------------*/
AP4_SidxAtom(AP4_UI32 reference_id,AP4_UI32 timescale,AP4_UI64 earliest_presentation_time,AP4_UI64 first_offset)58 AP4_SidxAtom::AP4_SidxAtom(AP4_UI32 reference_id,
59 AP4_UI32 timescale,
60 AP4_UI64 earliest_presentation_time,
61 AP4_UI64 first_offset) :
62 AP4_Atom(AP4_ATOM_TYPE_SIDX, AP4_FULL_ATOM_HEADER_SIZE+20, 0, 0),
63 m_ReferenceId(reference_id),
64 m_TimeScale(timescale),
65 m_EarliestPresentationTime(earliest_presentation_time),
66 m_FirstOffset(first_offset)
67 {
68 if ((earliest_presentation_time >> 32) || (first_offset >> 32)) {
69 m_Version = 1;
70 m_Size32 += 8;
71 }
72 }
73
74 /*----------------------------------------------------------------------
75 | AP4_SidxAtom::AP4_SidxAtom
76 +---------------------------------------------------------------------*/
AP4_SidxAtom(AP4_UI32 size,AP4_UI08 version,AP4_UI32 flags,AP4_ByteStream & stream)77 AP4_SidxAtom::AP4_SidxAtom(AP4_UI32 size,
78 AP4_UI08 version,
79 AP4_UI32 flags,
80 AP4_ByteStream& stream) :
81 AP4_Atom(AP4_ATOM_TYPE_SIDX, size, version, flags)
82 {
83 stream.ReadUI32(m_ReferenceId);
84 stream.ReadUI32(m_TimeScale);
85 if (version == 0) {
86 AP4_UI32 earliest_presentation_time = 0;
87 AP4_UI32 first_offset = 0;
88 stream.ReadUI32(earliest_presentation_time);
89 stream.ReadUI32(first_offset);
90 m_EarliestPresentationTime = earliest_presentation_time;
91 m_FirstOffset = first_offset;
92 } else {
93 stream.ReadUI64(m_EarliestPresentationTime);
94 stream.ReadUI64(m_FirstOffset);
95 }
96 AP4_UI16 reserved;
97 stream.ReadUI16(reserved);
98 AP4_UI16 reference_count = 0;
99 stream.ReadUI16(reference_count);
100 if (size < AP4_FULL_ATOM_HEADER_SIZE+4+4+(version==0?8:16)+2+2+reference_count*12) {
101 // not enough space to store all references, something's wrong
102 return;
103 }
104 m_References.SetItemCount(reference_count);
105 for (unsigned int i=0; i<reference_count; i++) {
106 AP4_UI32 value = 0;
107 stream.ReadUI32(value);
108 m_References[i].m_ReferenceType = (value&(1<<31))?1:0;
109 m_References[i].m_ReferencedSize = value & 0x7FFFFFFF;
110 stream.ReadUI32(m_References[i].m_SubsegmentDuration);
111 stream.ReadUI32(value);
112 m_References[i].m_StartsWithSap = ((value&(1<<31)) != 0);
113 m_References[i].m_SapType = (AP4_UI08)((value >>28)&0x07);
114 m_References[i].m_SapDeltaTime = value & 0x0FFFFFFF;
115 }
116 }
117
118 /*----------------------------------------------------------------------
119 | AP4_SidxAtom::WriteFields
120 +---------------------------------------------------------------------*/
121 AP4_Result
WriteFields(AP4_ByteStream & stream)122 AP4_SidxAtom::WriteFields(AP4_ByteStream& stream)
123 {
124 stream.WriteUI32(m_ReferenceId);
125 stream.WriteUI32(m_TimeScale);
126 if (m_Version == 0) {
127 stream.WriteUI32((AP4_UI32)m_EarliestPresentationTime);
128 stream.WriteUI32((AP4_UI32)m_FirstOffset);
129 } else {
130 stream.WriteUI64(m_EarliestPresentationTime);
131 stream.WriteUI64(m_FirstOffset);
132 }
133 stream.WriteUI16(0);
134 stream.WriteUI16((AP4_UI16)m_References.ItemCount());
135 for (unsigned int i=0; i<m_References.ItemCount(); i++) {
136 stream.WriteUI32((m_References[i].m_ReferenceType<<31) |
137 m_References[i].m_ReferencedSize);
138 stream.WriteUI32(m_References[i].m_SubsegmentDuration);
139 stream.WriteUI32(((m_References[i].m_StartsWithSap?1:0)<<31) |
140 (m_References[i].m_SapType << 28) |
141 m_References[i].m_SapDeltaTime);
142 }
143
144 return AP4_SUCCESS;
145 }
146
147 /*----------------------------------------------------------------------
148 | AP4_SidxAtom::InspectFields
149 +---------------------------------------------------------------------*/
150 AP4_Result
InspectFields(AP4_AtomInspector & inspector)151 AP4_SidxAtom::InspectFields(AP4_AtomInspector& inspector)
152 {
153 inspector.AddField("reference_ID", m_ReferenceId);
154 inspector.AddField("timescale", m_TimeScale);
155 inspector.AddField("earliest_presentation_time", m_EarliestPresentationTime);
156 inspector.AddField("first_offset", m_FirstOffset);
157
158 if (inspector.GetVerbosity() >= 1) {
159 AP4_UI32 reference_count = m_References.ItemCount();
160 inspector.StartArray("entries", reference_count);
161 for (unsigned int i=0; i<reference_count; i++) {
162 inspector.StartObject(NULL, 6, true);
163 inspector.AddField("reference_type", m_References[i].m_ReferenceType);
164 inspector.AddField("referenced_size", m_References[i].m_ReferencedSize);
165 inspector.AddField("subsegment_duration", m_References[i].m_SubsegmentDuration);
166 inspector.AddField("starts_with_SAP", m_References[i].m_StartsWithSap);
167 inspector.AddField("SAP_type", m_References[i].m_SapType);
168 inspector.AddField("SAP_delta_time", m_References[i].m_SapDeltaTime);
169 inspector.EndObject();
170 }
171 inspector.EndArray();
172 }
173
174 return AP4_SUCCESS;
175 }
176
177 /*----------------------------------------------------------------------
178 | AP4_SidxAtom::SetReferenceCount
179 +---------------------------------------------------------------------*/
180 void
SetReferenceCount(unsigned int count)181 AP4_SidxAtom::SetReferenceCount(unsigned int count) {
182 m_Size32 -= m_References.ItemCount()*12;
183 m_References.SetItemCount(count);
184 m_Size32 += m_References.ItemCount()*12;
185 }
186