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Ap4Movie.cpp：源码内容
							/*****************************************************************
|
|    AP4 - Movie
|
|    Copyright 2002-2005 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 "Ap4File.h"
#include "Ap4Atom.h"
#include "Ap4TrakAtom.h"
#include "Ap4MoovAtom.h"
#include "Ap4MvhdAtom.h"
#include "Ap4AtomFactory.h"
#include "Ap4Movie.h"
/*----------------------------------------------------------------------
|       AP4_TrackFinderById
+---------------------------------------------------------------------*/
class AP4_TrackFinderById : public AP4_List<AP4_Track>::Item::Finder
{
public:
    AP4_TrackFinderById(AP4_UI32 track_id) : m_TrackId(track_id) {}
    AP4_Result Test(AP4_Track* track) const {
        return track->GetId() == m_TrackId ? AP4_SUCCESS : AP4_FAILURE;
    }
private:
    AP4_UI32 m_TrackId;
};
/*----------------------------------------------------------------------
|       AP4_TrackFinderByType
+---------------------------------------------------------------------*/
class AP4_TrackFinderByType : public AP4_List<AP4_Track>::Item::Finder
{
public:
    AP4_TrackFinderByType(AP4_Track::Type type, AP4_Ordinal index = 0) : 
      m_Type(type), m_Index(index) {}
    AP4_Result Test(AP4_Track* track) const {
        if (track->GetType() == m_Type && m_Index-- == 0) {
            return AP4_SUCCESS;
        } else {
            return AP4_FAILURE;
        }
    }
private:
    AP4_Track::Type     m_Type;
    mutable AP4_Ordinal m_Index;
};
/*----------------------------------------------------------------------
|       AP4_Movie::AP4_Movie
+---------------------------------------------------------------------*/
AP4_Movie::AP4_Movie(AP4_UI32 time_scale)
{
    m_MoovAtom = new AP4_MoovAtom();
    m_MvhdAtom = new AP4_MvhdAtom(0, 0, 
                                  time_scale, 
                                  0, 
                                  0x00010000,
                                  0x0100);
    m_MoovAtom->AddChild(m_MvhdAtom);
}
/*----------------------------------------------------------------------
|       AP4_Movie::AP4_Moovie
+---------------------------------------------------------------------*/
AP4_Movie::AP4_Movie(AP4_MoovAtom* moov, AP4_ByteStream& mdat) :
    m_MoovAtom(moov)
{
    // ignore null atoms
    if (moov == NULL) return;
    // get the time scale
    AP4_UI32 time_scale;
    m_MvhdAtom = dynamic_cast<AP4_MvhdAtom*>(moov->GetChild(AP4_ATOM_TYPE_MVHD));
    if (m_MvhdAtom) {
        time_scale = m_MvhdAtom->GetTimeScale();
    } else {
        time_scale = 0;
    }
    // get all tracks
    AP4_List<AP4_TrakAtom>* trak_atoms;
    trak_atoms = &moov->GetTrakAtoms();
    AP4_List<AP4_TrakAtom>::Item* item = trak_atoms->FirstItem();
    while (item) {
        AP4_Track* track = new AP4_Track(*item->GetData(), 
                                         mdat,
                                         time_scale);
        m_Tracks.Add(track);
        item = item->GetNext();
    }
}
    
/*----------------------------------------------------------------------
|       AP4_Movie::~AP4_Movie
+---------------------------------------------------------------------*/
AP4_Movie::~AP4_Movie()
{
    m_Tracks.DeleteReferences();
    delete m_MoovAtom;
}
/*----------------------------------------------------------------------
|       AP4_Movie::Inspect
+---------------------------------------------------------------------*/
AP4_Result
AP4_Movie::Inspect(AP4_AtomInspector& inspector)
{
    // dump the moov atom
    return m_MoovAtom->Inspect(inspector);
}
/*----------------------------------------------------------------------
|       AP4_Movie::GetTrack
+---------------------------------------------------------------------*/
AP4_Track*
AP4_Movie::GetTrack(AP4_UI32 track_id)
{
    AP4_Track* track = NULL;
    if (AP4_SUCCEEDED(m_Tracks.Find(AP4_TrackFinderById(track_id), track))) {
        return track;
    } else {
        return NULL;
    }
}
/*----------------------------------------------------------------------
|       AP4_Movie::GetTrack
+---------------------------------------------------------------------*/
AP4_Track*
AP4_Movie::GetTrack(AP4_Track::Type track_type, AP4_Ordinal index)
{
    AP4_Track* track = NULL;
    if (AP4_SUCCEEDED(m_Tracks.Find(AP4_TrackFinderByType(track_type, index), track))) {
        return track;
    } else {
        return NULL;
    }
}
/*----------------------------------------------------------------------
|       AP4_Movie::AddTrack
+---------------------------------------------------------------------*/
AP4_Result
AP4_Movie::AddTrack(AP4_Track* track)
{
    // assign an ID to the track unless it already has one
    if (track->GetId() == 0) {
        track->SetId(m_Tracks.ItemCount()+1);
    }
    // if we don't have a time scale, use the one from the track
    if (m_MvhdAtom->GetTimeScale() == 0) {
        m_MvhdAtom->SetTimeScale(track->GetMediaTimeScale());
    }
    // adjust the parent time scale of the track
    track->SetMovieTimeScale(m_MvhdAtom->GetTimeScale());
    // update the movie duration
    if (m_MvhdAtom->GetDuration() < track->GetDuration()) {
        m_MvhdAtom->SetDuration(track->GetDuration());
    }
    
    // attach the track as a child
    m_MoovAtom->AddChild(track->GetTrakAtom());
    m_Tracks.Add(track);
    return AP4_SUCCESS;
}
/*----------------------------------------------------------------------
|       AP4_Movie::GetTimeScale
+---------------------------------------------------------------------*/
AP4_UI32
AP4_Movie::GetTimeScale()
{
    if (m_MvhdAtom) {
        return m_MvhdAtom->GetTimeScale();
    } else {
        return 0;
    }
}
/*----------------------------------------------------------------------
|       AP4_Movie::GetDuration
+---------------------------------------------------------------------*/
AP4_UI32
AP4_Movie::GetDuration()
{
    if (m_MvhdAtom) {
        return m_MvhdAtom->GetDuration();
    } else {
        return 0;
    }
}
/*----------------------------------------------------------------------
|       AP4_Movie::GetDurationMs
+---------------------------------------------------------------------*/
AP4_UI32
AP4_Movie::GetDurationMs()
{
    if (m_MvhdAtom) {
        return m_MvhdAtom->GetDurationMs();
    } else {
        return 0;
    }
}

						