C++ AP4_AtomParent::GetChild方法代码示例

/*----------------------------------------------------------------------
|   AP4_OmaDcfDecryptingProcessor:Initialize
+---------------------------------------------------------------------*/
AP4_Result
AP4_OmaDcfDecryptingProcessor::Initialize(AP4_AtomParent&   top_level,
        AP4_ByteStream&   /* stream */,
        ProgressListener* listener)
{
    // decide which processor to instantiate based on the file type
    AP4_FtypAtom* ftyp = AP4_DYNAMIC_CAST(AP4_FtypAtom, top_level.GetChild(AP4_ATOM_TYPE_FTYP));
    if (ftyp) {
        if (ftyp->GetMajorBrand() == AP4_OMA_DCF_BRAND_ODCF || ftyp->HasCompatibleBrand(AP4_OMA_DCF_BRAND_ODCF)) {
            return AP4_OmaDcfAtomDecrypter::DecryptAtoms(top_level, listener, m_BlockCipherFactory, m_KeyMap);
        } else {
            return AP4_ERROR_INVALID_FORMAT;
        }
    } else {
        return AP4_SUCCESS;
    }
}

/*----------------------------------------------------------------------
|   AP4_MarlinIpmpDecryptingProcessor:Initialize
+---------------------------------------------------------------------*/
AP4_Result 
AP4_MarlinIpmpDecryptingProcessor::Initialize(AP4_AtomParent&   top_level, 
                                              AP4_ByteStream&   stream,
                                              ProgressListener* /*listener*/)
{
    AP4_Result result = AP4_MarlinIpmpParser::Parse(top_level, stream, m_SinfEntries, true);
    if (AP4_FAILED(result)) return result;

    // update the file type
    AP4_FtypAtom* ftyp = AP4_DYNAMIC_CAST(AP4_FtypAtom, top_level.GetChild(AP4_ATOM_TYPE_FTYP));
    if (ftyp) {
        ftyp->SetMajorBrandAndVersion(AP4_FTYP_BRAND_MP42, 1);
        for (unsigned int i=0; i<ftyp->GetCompatibleBrands().ItemCount(); i++) {
            if (ftyp->GetCompatibleBrands()[i] == AP4_MARLIN_BRAND_MGSV) {
                ftyp->GetCompatibleBrands()[i] = AP4_FTYP_BRAND_MP42;
            }
        }
    }    
    
    return AP4_SUCCESS;
}

/*----------------------------------------------------------------------
|   AP4_MarlinIpmpEncryptingProcessor::Initialize
+---------------------------------------------------------------------*/
AP4_Result 
AP4_MarlinIpmpEncryptingProcessor::Initialize(
    AP4_AtomParent&                  top_level,
    AP4_ByteStream&                  /*stream*/,
    AP4_Processor::ProgressListener* /*listener = NULL*/)
{
    // get the moov atom
    AP4_MoovAtom* moov = AP4_DYNAMIC_CAST(AP4_MoovAtom, top_level.GetChild(AP4_ATOM_TYPE_MOOV));
    if (moov == NULL) return AP4_ERROR_INVALID_FORMAT;
    
    // deal with the file type
    AP4_FtypAtom* ftyp = AP4_DYNAMIC_CAST(AP4_FtypAtom, top_level.GetChild(AP4_ATOM_TYPE_FTYP));
    if (ftyp) {
        // remove the atom, it will be replaced with a new one
        top_level.RemoveChild(ftyp);
        
        // keep the existing brand and compatible brands
        AP4_Array<AP4_UI32> compatible_brands;
        compatible_brands.EnsureCapacity(ftyp->GetCompatibleBrands().ItemCount()+1);
        for (unsigned int i=0; i<ftyp->GetCompatibleBrands().ItemCount(); i++) {
            compatible_brands.Append(ftyp->GetCompatibleBrands()[i]);
        }
        
        // add the MGSV compatible brand if it is not already there
        if (!ftyp->HasCompatibleBrand(AP4_MARLIN_BRAND_MGSV)) {
            compatible_brands.Append(AP4_MARLIN_BRAND_MGSV);
        }

        // create a replacement for the major brand
        AP4_FtypAtom* new_ftyp = new AP4_FtypAtom(AP4_MARLIN_BRAND_MGSV,
                                                  0x13c078c, //AP4_MARLIN_BRAND_MGSV_MAJOR_VERSION,
                                                  &compatible_brands[0],
                                                  compatible_brands.ItemCount());
        delete ftyp;
        ftyp = new_ftyp;
    } else {
        AP4_UI32 isom = AP4_FTYP_BRAND_ISOM;
        ftyp = new AP4_FtypAtom(AP4_MARLIN_BRAND_MGSV, 0, &isom, 1);
    }
    
    // insert the ftyp atom as the first child
    top_level.AddChild(ftyp, 0);

    // create and 'mpod' track reference atom
    AP4_TrefTypeAtom* mpod = new AP4_TrefTypeAtom(AP4_ATOM_TYPE_MPOD);
    
    // look for an available track ID, starting at 1
    unsigned int od_track_id       = 0;
    unsigned int od_track_position = 0;
    AP4_List<AP4_TrakAtom>::Item* trak_item = moov->GetTrakAtoms().FirstItem();
    while (trak_item) {
        AP4_TrakAtom* trak = trak_item->GetData();
        if (trak) {
            od_track_position++;
            if (trak->GetId() >= od_track_id) {
                od_track_id = trak->GetId()+1;
            }
            
            // if the track is encrypted, reference it in the mpod
            if (m_KeyMap.GetKey(trak->GetId())) {
                mpod->AddTrackId(trak->GetId());
            }
            
            //m_SinfEntries.Add(new SinfEntry(trak->GetId(), NULL));
        }
        trak_item = trak_item->GetNext();
    }
    
    // check that there was at least one track in the file
    if (od_track_id == 0) return AP4_ERROR_INVALID_FORMAT;
    
    // create an initial object descriptor
    AP4_InitialObjectDescriptor* iod = 
        // FIXME: get real values from the property map
        new AP4_InitialObjectDescriptor(AP4_DESCRIPTOR_TAG_MP4_IOD,
                                        1022, // object descriptor id
                                        false, 
                                        0xFE,    // OD profile level (0xFE = No OD profile specified)
                                        0xFF,    // scene profile level
                                        0xFE,    // audio profile level
                                        0xFE,    // visual profile level
                                        0xFF);   // graphics profile

    // create an ES_ID_Inc subdescriptor and add it to the initial object descriptor
    AP4_EsIdIncDescriptor* es_id_inc = new AP4_EsIdIncDescriptor(od_track_id);
    iod->AddSubDescriptor(es_id_inc);
    
    // create an iods atom to hold the initial object descriptor
    AP4_IodsAtom* iods = new AP4_IodsAtom(iod);
    
    // add the iods atom to the moov atom (try to put it just after mvhd)
    int iods_position = 0;
    int item_position = 0;
    for (AP4_List<AP4_Atom>::Item* item = moov->GetChildren().FirstItem();
         item;
         ++item) {
         ++item_position;
//.........这里部分代码省略.........

/*----------------------------------------------------------------------
|   AP4_MarlinIpmpParser:Parse
+---------------------------------------------------------------------*/
AP4_Result 
AP4_MarlinIpmpParser::Parse(AP4_AtomParent&      top_level, 
                            AP4_ByteStream&      stream,
                            AP4_List<SinfEntry>& sinf_entries,
                            bool                 remove_od_data)
{
    // check the file type
    AP4_FtypAtom* ftyp = AP4_DYNAMIC_CAST(AP4_FtypAtom, top_level.GetChild(AP4_ATOM_TYPE_FTYP));
    if (ftyp == NULL ||
        (ftyp->GetMajorBrand() != AP4_MARLIN_BRAND_MGSV && !ftyp->HasCompatibleBrand(AP4_MARLIN_BRAND_MGSV))) {
        return AP4_ERROR_INVALID_FORMAT;
    }
    
    // check the initial object descriptor and get the OD Track ID
    AP4_IodsAtom* iods = AP4_DYNAMIC_CAST(AP4_IodsAtom, top_level.FindChild("moov/iods"));
    AP4_UI32      od_track_id = 0;
    if (iods == NULL) return AP4_ERROR_INVALID_FORMAT;
    const AP4_ObjectDescriptor* od = iods->GetObjectDescriptor();
    if (od == NULL) return AP4_ERROR_INVALID_FORMAT;
    AP4_EsIdIncDescriptor* es_id_inc = AP4_DYNAMIC_CAST(AP4_EsIdIncDescriptor, od->FindSubDescriptor(AP4_DESCRIPTOR_TAG_ES_ID_INC));
    if (es_id_inc == NULL) return AP4_ERROR_INVALID_FORMAT;
    od_track_id = es_id_inc->GetTrackId();
    
    // find the track pointed to by the descriptor
    AP4_MoovAtom* moov = AP4_DYNAMIC_CAST(AP4_MoovAtom, top_level.GetChild(AP4_ATOM_TYPE_MOOV));
    if (moov == NULL) return AP4_ERROR_INVALID_FORMAT;
    AP4_TrakAtom* od_trak = NULL;
    AP4_List<AP4_TrakAtom>::Item* trak_item = moov->GetTrakAtoms().FirstItem();
    while (trak_item) {
        AP4_TrakAtom* trak = trak_item->GetData();
        if (trak) {
            if (trak->GetId() == od_track_id) {
                od_trak = trak;
            } else {
                sinf_entries.Add(new SinfEntry(trak->GetId(), NULL));
            }
        }
        trak_item = trak_item->GetNext();
    }

    // check that we have found the OD track 
    if (od_trak == NULL) return AP4_ERROR_INVALID_FORMAT;

    // look for the 'mpod' trak references
    AP4_TrefTypeAtom* track_references;
    track_references = AP4_DYNAMIC_CAST(AP4_TrefTypeAtom, od_trak->FindChild("tref/mpod"));
    if (track_references == NULL) return AP4_ERROR_INVALID_FORMAT;

    // create an AP4_Track object from the trak atom and check that it has samples
    AP4_Track* od_track = new AP4_Track(*od_trak, stream, 0);
    if (od_track->GetSampleCount() < 1) {
        delete od_track;
        return AP4_ERROR_INVALID_FORMAT;
    }
    
    // get the first sample (in this version, we only look at a single OD command)
    AP4_Sample od_sample;
    AP4_Result result = od_track->GetSample(0, od_sample);
    if (AP4_FAILED(result)) {
        delete od_track;
        return AP4_ERROR_INVALID_FORMAT;
    }
    
    // adapt the sample data into a byte stream for parsing
    AP4_DataBuffer sample_data;
    od_sample.ReadData(sample_data);
    AP4_MemoryByteStream* sample_stream = new AP4_MemoryByteStream(sample_data);
    
    // look for one ObjectDescriptorUpdate command and 
    // one IPMP_DescriptorUpdate command
    AP4_DescriptorUpdateCommand* od_update = NULL;
    AP4_DescriptorUpdateCommand* ipmp_update = NULL;
    do {
        AP4_Command* command = NULL;
        result = AP4_CommandFactory::CreateCommandFromStream(*sample_stream, command);
        if (AP4_SUCCEEDED(result)) {
            // found a command in the sample, check the type
            switch (command->GetTag()) {
              case AP4_COMMAND_TAG_OBJECT_DESCRIPTOR_UPDATE:
                if (od_update == NULL) {
                    od_update = AP4_DYNAMIC_CAST(AP4_DescriptorUpdateCommand, command);
                }
                break;
                
              case AP4_COMMAND_TAG_IPMP_DESCRIPTOR_UPDATE:
                if (ipmp_update == NULL) {
                    ipmp_update = AP4_DYNAMIC_CAST(AP4_DescriptorUpdateCommand, command);
                }
                break;

              default:
                break;
            }
        }
    } while (AP4_SUCCEEDED(result));
    sample_stream->Release();
    sample_stream = NULL;
//.........这里部分代码省略.........

/*----------------------------------------------------------------------
|   DcfParser_ParseV2Header
+---------------------------------------------------------------------*/
static BLT_Result
DcfParser_ParseV2Header(DcfParser* self, ATX_InputStream* stream)
{
    /* rewind the byte stream */
    ATX_InputStream_Seek(stream, 0);

    /* parse the atoms from the stream */
    AP4_ByteStream* mp4_stream = new ATX_InputStream_To_AP4_ByteStream_Adapter(stream);
    AP4_AtomParent  atoms;
    AP4_Result result = AP4_DefaultAtomFactory::Instance.CreateAtomsFromStream(*mp4_stream, atoms);
    mp4_stream->Release();
    
    AP4_ByteStream* decrypting_stream = NULL;
    AP4_ContainerAtom* odrm = dynamic_cast<AP4_ContainerAtom*>(atoms.GetChild(AP4_ATOM_TYPE_ODRM));
    if (odrm) {
        AP4_OdheAtom* odhe = dynamic_cast<AP4_OdheAtom*>(odrm->GetChild(AP4_ATOM_TYPE_ODHE));
        AP4_OddaAtom* odda = dynamic_cast<AP4_OddaAtom*>(odrm->GetChild(AP4_ATOM_TYPE_ODDA));
        if (odhe && odda) {
            const char* content_id = "";

            /* get the content ID */
            AP4_OhdrAtom* ohdr = dynamic_cast<AP4_OhdrAtom*>(odhe->GetChild(AP4_ATOM_TYPE_OHDR));
            if (ohdr) {
                content_id = ohdr->GetContentId().GetChars();
            }

            /* get the content key */
            NPT_DataBuffer key;
            result = DcfParser_GetContentKey(self, content_id, key);
            if (BLT_FAILED(result)) {
                ATX_LOG_FINE_2("GetKeyForContent(%s) returned %d", 
                               content_id, 
                               result);
                return BLT_ERROR_NO_MEDIA_KEY;
            }

            /* create the decrypting stream */
            result = AP4_OmaDcfAtomDecrypter::CreateDecryptingStream(*odrm,
                                                                     key.GetData(),
                                                                     key.GetDataSize(),
                                                                     self->cipher_factory,
                                                                     decrypting_stream);
            if (AP4_SUCCEEDED(result)) {
                /* update the content type */
                ATX_CopyStringN(self->input.content_type,
                                odhe->GetContentType().GetChars(),
                                sizeof(self->input.content_type));
                    
                /* update the encrypted size */
                self->input.encrypted_size = odda->GetEncryptedDataLength();
            }
        }
    }

    /* check that we have found what we needed in the atoms */
    if (decrypting_stream == NULL) return BLT_ERROR_INVALID_MEDIA_FORMAT;

    /* update the output size */
    AP4_LargeSize plaintext_size = 0;
    if (AP4_SUCCEEDED(decrypting_stream->GetSize(plaintext_size))) {
        self->output.size = plaintext_size;
    } else {
        self->output.size = self->input.encrypted_size;
    }
    
    /* create a reverse adapter */
    result = AP4_ByteStream_To_ATX_InputStream_Adapter_Create(decrypting_stream, &self->output.stream);
    decrypting_stream->Release();

    return BLT_SUCCESS;
}

/*----------------------------------------------------------------------
|   AP4_MarlinIpmpEncryptingProcessor::Initialize
+---------------------------------------------------------------------*/
AP4_Result 
AP4_MarlinIpmpEncryptingProcessor::Initialize(
    AP4_AtomParent&                  top_level,
    AP4_ByteStream&                  /*stream*/,
    AP4_Processor::ProgressListener* /*listener = NULL*/)
{
    // get the moov atom
    AP4_MoovAtom* moov = AP4_DYNAMIC_CAST(AP4_MoovAtom, top_level.GetChild(AP4_ATOM_TYPE_MOOV));
    if (moov == NULL) return AP4_ERROR_INVALID_FORMAT;
    
    // deal with the file type
    AP4_FtypAtom* ftyp = AP4_DYNAMIC_CAST(AP4_FtypAtom, top_level.GetChild(AP4_ATOM_TYPE_FTYP));
    if (ftyp) {
        // remove the atom, it will be replaced with a new one
        top_level.RemoveChild(ftyp);
        
        // keep the existing brand and compatible brands
        AP4_Array<AP4_UI32> compatible_brands;
        compatible_brands.EnsureCapacity(ftyp->GetCompatibleBrands().ItemCount()+1);
        for (unsigned int i=0; i<ftyp->GetCompatibleBrands().ItemCount(); i++) {
            compatible_brands.Append(ftyp->GetCompatibleBrands()[i]);
        }
        
        // add the MGSV compatible brand if it is not already there
        if (!ftyp->HasCompatibleBrand(AP4_MARLIN_BRAND_MGSV)) {
            compatible_brands.Append(AP4_MARLIN_BRAND_MGSV);
        }

        // create a replacement for the major brand
        AP4_FtypAtom* new_ftyp = new AP4_FtypAtom(AP4_MARLIN_BRAND_MGSV,
                                                  0x13c078c, //AP4_MARLIN_BRAND_MGSV_MAJOR_VERSION,
                                                  &compatible_brands[0],
                                                  compatible_brands.ItemCount());
        delete ftyp;
        ftyp = new_ftyp;
    } else {
        AP4_UI32 isom = AP4_FTYP_BRAND_ISOM;
        ftyp = new AP4_FtypAtom(AP4_MARLIN_BRAND_MGSV, 0, &isom, 1);
    }
    
    // insert the ftyp atom as the first child
    top_level.AddChild(ftyp, 0);

    // create and 'mpod' track reference atom
    AP4_TrefTypeAtom* mpod = new AP4_TrefTypeAtom(AP4_ATOM_TYPE_MPOD);
    
    // look for an available track ID, starting at 1
    unsigned int od_track_id       = 0;
    unsigned int od_track_position = 0;
    for (AP4_List<AP4_TrakAtom>::Item* trak_item = moov->GetTrakAtoms().FirstItem();
                                       trak_item;
                                       trak_item = trak_item->GetNext()) {
        AP4_TrakAtom* trak = trak_item->GetData();
        if (trak) {
            od_track_position++;
            if (trak->GetId() >= od_track_id) {
                od_track_id = trak->GetId()+1;
            }
            
            // if the track is encrypted, reference it in the mpod
            if (m_KeyMap.GetKey(trak->GetId())) {
                mpod->AddTrackId(trak->GetId());
            }
            
            //m_SinfEntries.Add(new SinfEntry(trak->GetId(), NULL));
        }   
    }
    
    // check that there was at least one track in the file
    if (od_track_id == 0) return AP4_ERROR_INVALID_FORMAT;
    
    // create an initial object descriptor
    AP4_InitialObjectDescriptor* iod = 
        // FIXME: get real values from the property map
        new AP4_InitialObjectDescriptor(AP4_DESCRIPTOR_TAG_MP4_IOD,
                                        1022, // object descriptor id
                                        false, 
                                        0xFE,    // OD profile level (0xFE = No OD profile specified)
                                        0xFF,    // scene profile level
                                        0xFE,    // audio profile level
                                        0xFE,    // visual profile level
                                        0xFF);   // graphics profile

    // create an ES_ID_Inc subdescriptor and add it to the initial object descriptor
    AP4_EsIdIncDescriptor* es_id_inc = new AP4_EsIdIncDescriptor(od_track_id);
    iod->AddSubDescriptor(es_id_inc);
    
    // create an iods atom to hold the initial object descriptor
    AP4_IodsAtom* iods = new AP4_IodsAtom(iod);
    
    // add the iods atom to the moov atom (try to put it just after mvhd)
    int iods_position = 0;
    int item_position = 0;
    for (AP4_List<AP4_Atom>::Item* moov_item = moov->GetChildren().FirstItem();
                                   moov_item;
                                   moov_item = moov_item->GetNext()) {
         ++item_position;
//.........这里部分代码省略.........