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Ap4StcoAtom.cpp：源码内容
							/*****************************************************************
|
|    AP4 - stco Atoms 
|
|    Copyright 2002 Gilles Boccon-Gibod
|
|
|    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 "Ap4.h"
#include "Ap4StcoAtom.h"
#include "Ap4AtomFactory.h"
#include "Ap4Utils.h"
/*----------------------------------------------------------------------
|       AP4_StcoAtom::AP4_StcoAtom
+---------------------------------------------------------------------*/
AP4_StcoAtom::AP4_StcoAtom(AP4_UI32* entries, AP4_UI32 entry_count) :
AP4_Atom(AP4_ATOM_TYPE_STCO,  
         AP4_FULL_ATOM_HEADER_SIZE+4+entry_count*4, 
         true),
         m_Entries(new AP4_UI32[entry_count]),
         m_EntryCount(entry_count)
{
    memcpy(m_Entries, entries, m_EntryCount*4);
}
/*----------------------------------------------------------------------
|       AP4_StcoAtom::AP4_StcoAtom
+---------------------------------------------------------------------*/
AP4_StcoAtom::AP4_StcoAtom(AP4_Size size, AP4_ByteStream& stream) :
    AP4_Atom(AP4_ATOM_TYPE_STCO, size, true, stream)
{
    stream.ReadUI32(m_EntryCount);
    if (m_EntryCount > (size-AP4_FULL_ATOM_HEADER_SIZE-4)/4) {
        m_EntryCount = (size-AP4_FULL_ATOM_HEADER_SIZE-4)/4;
    }
    m_Entries = new AP4_UI32[m_EntryCount];
    for (AP4_Ordinal i=0; i<m_EntryCount; i++) {
        stream.ReadUI32(m_Entries[i]);
    }
}
/*----------------------------------------------------------------------
|       AP4_StcoAtom::~AP4_StcoAtom
+---------------------------------------------------------------------*/
AP4_StcoAtom::~AP4_StcoAtom()
{
    delete[] m_Entries;
}
/*----------------------------------------------------------------------
|       AP4_StcoAtom::GetChunkOffset
+---------------------------------------------------------------------*/
AP4_Result
AP4_StcoAtom::GetChunkOffset(AP4_Ordinal chunk, AP4_Offset& chunk_offset)
{
    // check the bounds
    if (chunk > m_EntryCount || chunk == 0) {
        return AP4_ERROR_OUT_OF_RANGE;
    }
    // get the chunk offset
    chunk_offset = m_Entries[chunk - 1]; // m_Entries is zero index based
    return AP4_SUCCESS;
}
/*----------------------------------------------------------------------
|       AP4_StcoAtom::SetChunkOffset
+---------------------------------------------------------------------*/
AP4_Result
AP4_StcoAtom::SetChunkOffset(AP4_Ordinal chunk, AP4_Offset chunk_offset)
{
    // check the bounds
    if (chunk > m_EntryCount || chunk == 0) {
        return AP4_ERROR_OUT_OF_RANGE;
    }
    // get the chunk offset
    m_Entries[chunk - 1] = chunk_offset; // m_Entries is zero index based
    return AP4_SUCCESS;
}
/*----------------------------------------------------------------------
|       AP4_StcoAtom::AdjustChunkOffsets
+---------------------------------------------------------------------*/
AP4_Result
AP4_StcoAtom::AdjustChunkOffsets(AP4_Offset offset)
{
    for (AP4_Ordinal i=0; i<m_EntryCount; i++) {
        m_Entries[i] += offset;
    }
    return AP4_SUCCESS;
}
/*----------------------------------------------------------------------
|       AP4_StcoAtom::WriteFields
+---------------------------------------------------------------------*/
AP4_Result
AP4_StcoAtom::WriteFields(AP4_ByteStream& stream)
{
    AP4_Result result;
    // entry count
    result = stream.WriteUI32(m_EntryCount);
    if (AP4_FAILED(result)) return result;
    // entries
    for (AP4_Ordinal i=0; i<m_EntryCount; i++) {
        result = stream.WriteUI32(m_Entries[i]);
        if (AP4_FAILED(result)) return result;
    }
    return result;
}
/*----------------------------------------------------------------------
|       AP4_StcoAtom::InspectFields
+---------------------------------------------------------------------*/
AP4_Result
AP4_StcoAtom::InspectFields(AP4_AtomInspector& inspector)
{
    inspector.AddField("entry_count", m_EntryCount);
    return AP4_SUCCESS;
}

						