mirror of
https://github.com/axiomatic-systems/Bento4.git
synced 2026-01-19 00:05:12 +08:00
131 lines
4.6 KiB
C++
131 lines
4.6 KiB
C++
/*****************************************************************
|
|
|
|
|
| AP4 - iSFM Atoms
|
|
|
|
|
| Copyright 2002-2008 Axiomatic Systems, LLC
|
|
|
|
|
|
|
|
| This file is part of Bento4/AP4 (MP4 Atom Processing Library).
|
|
|
|
|
| Unless you have obtained Bento4 under a difference license,
|
|
| this version of Bento4 is Bento4|GPL.
|
|
| Bento4|GPL 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 2, or (at your option)
|
|
| any later version.
|
|
|
|
|
| Bento4|GPL 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 Bento4|GPL; see the file COPYING. If not, write to the
|
|
| Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA
|
|
| 02111-1307, USA.
|
|
|
|
|
****************************************************************/
|
|
|
|
/*----------------------------------------------------------------------
|
|
| includes
|
|
+---------------------------------------------------------------------*/
|
|
#include "Ap4Utils.h"
|
|
#include "Ap4IsfmAtom.h"
|
|
|
|
/*----------------------------------------------------------------------
|
|
| dynamic cast support
|
|
+---------------------------------------------------------------------*/
|
|
AP4_DEFINE_DYNAMIC_CAST_ANCHOR(AP4_IsfmAtom)
|
|
|
|
/*----------------------------------------------------------------------
|
|
| AP4_IsfmAtom::Create
|
|
+---------------------------------------------------------------------*/
|
|
AP4_IsfmAtom*
|
|
AP4_IsfmAtom::Create(AP4_Size size, AP4_ByteStream& stream)
|
|
{
|
|
AP4_UI08 version;
|
|
AP4_UI32 flags;
|
|
if (size < AP4_FULL_ATOM_HEADER_SIZE) return NULL;
|
|
if (AP4_FAILED(AP4_Atom::ReadFullHeader(stream, version, flags))) return NULL;
|
|
if (version != 0) return NULL;
|
|
return new AP4_IsfmAtom(size, version, flags, stream);
|
|
}
|
|
|
|
/*----------------------------------------------------------------------
|
|
| AP4_IsfmAtom::AP4_IsfmAtom
|
|
+---------------------------------------------------------------------*/
|
|
AP4_IsfmAtom::AP4_IsfmAtom(bool selective_encryption,
|
|
AP4_UI08 key_length_indicator,
|
|
AP4_UI08 iv_length) :
|
|
AP4_Atom(AP4_ATOM_TYPE_ISFM, AP4_FULL_ATOM_HEADER_SIZE+3, 0, 0),
|
|
m_SelectiveEncryption(selective_encryption),
|
|
m_KeyIndicatorLength(key_length_indicator),
|
|
m_IvLength(iv_length)
|
|
{
|
|
}
|
|
|
|
/*----------------------------------------------------------------------
|
|
| AP4_IsfmAtom::AP4_IsfmAtom
|
|
+---------------------------------------------------------------------*/
|
|
AP4_IsfmAtom::AP4_IsfmAtom(AP4_UI32 size,
|
|
AP4_UI08 version,
|
|
AP4_UI32 flags,
|
|
AP4_ByteStream& stream) :
|
|
AP4_Atom(AP4_ATOM_TYPE_ISFM, size, version, flags),
|
|
m_KeyIndicatorLength(0),
|
|
m_IvLength(0)
|
|
{
|
|
AP4_UI08 s;
|
|
stream.ReadUI08(s);
|
|
m_SelectiveEncryption = ((s&0x80) != 0);
|
|
stream.ReadUI08(m_KeyIndicatorLength);
|
|
stream.ReadUI08(m_IvLength);
|
|
}
|
|
|
|
/*----------------------------------------------------------------------
|
|
| AP4_IsfmAtom::Clone
|
|
+---------------------------------------------------------------------*/
|
|
AP4_Atom*
|
|
AP4_IsfmAtom::Clone()
|
|
{
|
|
return new AP4_IsfmAtom(m_SelectiveEncryption,
|
|
m_KeyIndicatorLength,
|
|
m_IvLength);
|
|
}
|
|
|
|
/*----------------------------------------------------------------------
|
|
| AP4_IsfmAtom::WriteFields
|
|
+---------------------------------------------------------------------*/
|
|
AP4_Result
|
|
AP4_IsfmAtom::WriteFields(AP4_ByteStream& stream)
|
|
{
|
|
AP4_Result result;
|
|
|
|
// selective encryption
|
|
result = stream.WriteUI08(m_SelectiveEncryption ? 0x80 : 0);
|
|
if (AP4_FAILED(result)) return result;
|
|
|
|
// key indicator length
|
|
result = stream.WriteUI08(m_KeyIndicatorLength);
|
|
if (AP4_FAILED(result)) return result;
|
|
|
|
// IV length
|
|
result = stream.WriteUI08(m_IvLength);
|
|
if (AP4_FAILED(result)) return result;
|
|
|
|
return AP4_SUCCESS;
|
|
}
|
|
|
|
/*----------------------------------------------------------------------
|
|
| AP4_IsfmAtom::InspectFields
|
|
+---------------------------------------------------------------------*/
|
|
AP4_Result
|
|
AP4_IsfmAtom::InspectFields(AP4_AtomInspector& inspector)
|
|
{
|
|
inspector.AddField("selective_encryption", m_SelectiveEncryption);
|
|
inspector.AddField("key_indicator_length", m_KeyIndicatorLength);
|
|
inspector.AddField("IV_length", m_IvLength);
|
|
|
|
return AP4_SUCCESS;
|
|
}
|