/*---------------------------------------------------------------------- | main +---------------------------------------------------------------------*/ int main(int argc, char** argv) { if (argc < 2) { PrintUsageAndExit(); } // default options Options.verbose = false; Options.input = NULL; Options.init_segment_name = AP4_SPLIT_DEFAULT_INIT_SEGMENT_NAME; Options.media_segment_name = AP4_SPLIT_DEFAULT_MEDIA_SEGMENT_NAME; Options.pattern_params = AP4_SPLIT_DEFAULT_PATTERN_PARAMS; Options.start_number = 1; Options.track_id = 0; Options.audio_only = false; Options.video_only = false; Options.init_only = false; Options.track_filter = 0; // parse command line AP4_Result result; char** args = argv+1; while (const char* arg = *args++) { if (!strcmp(arg, "--verbose")) { Options.verbose = true; } else if (!strcmp(arg, "--init-segment")) { if (*args == NULL) { fprintf(stderr, "ERROR: missing argument after --init-segment option\n"); return 1; } Options.init_segment_name = *args++; } else if (!strcmp(arg, "--media-segment")) { if (*args == NULL) { fprintf(stderr, "ERROR: missing argument after --media-segment option\n"); return 1; } Options.media_segment_name = *args++; } else if (!strcmp(arg, "--pattern-parameters")) { if (*args == NULL) { fprintf(stderr, "ERROR: missing argument after --pattern-params option\n"); return 1; } Options.pattern_params = *args++; } else if (!strcmp(arg, "--track-id")) { Options.track_id = strtoul(*args++, NULL, 10); } else if (!strcmp(arg, "--start-number")) { Options.start_number = strtoul(*args++, NULL, 10); } else if (!strcmp(arg, "--init-only")) { Options.init_only = true; } else if (!strcmp(arg, "--audio")) { Options.audio_only = true; } else if (!strcmp(arg, "--video")) { Options.video_only = true; } else if (Options.input == NULL) { Options.input = arg; } else { fprintf(stderr, "ERROR: unexpected argument\n"); return 1; } } // check args if (Options.input == NULL) { fprintf(stderr, "ERROR: missing input file name\n"); return 1; } if ((Options.audio_only && (Options.video_only || Options.track_id)) || (Options.video_only && (Options.audio_only || Options.track_id)) || (Options.track_id && (Options.audio_only || Options.video_only))) { fprintf(stderr, "ERROR: --audio, --video and --track-id options are mutualy exclusive\n"); return 1; } if (strlen(Options.pattern_params) < 1) { fprintf(stderr, "ERROR: --pattern-params argument is too short\n"); return 1; } if (strlen(Options.pattern_params) > 2) { fprintf(stderr, "ERROR: --pattern-params argument is too long\n"); return 1; } const char* cursor = Options.pattern_params; while (*cursor) { if (*cursor != 'I' && *cursor != 'N') { fprintf(stderr, "ERROR: invalid pattern parameter '%c'\n", *cursor); return 1; } ++cursor; } // create the input stream AP4_ByteStream* input = NULL; result = AP4_FileByteStream::Create(Options.input, AP4_FileByteStream::STREAM_MODE_READ, input); if (AP4_FAILED(result)) { fprintf(stderr, "ERROR: cannot open input (%d)\n", result); return 1; } // get the movie AP4_File* file = new AP4_File(*input, AP4_DefaultAtomFactory::Instance, true); AP4_Movie* movie = file->GetMovie(); if (movie == NULL) { fprintf(stderr, "no movie found in file\n"); return 1; } // filter tracks if required if (Options.audio_only) { AP4_Track* track = movie->GetTrack(AP4_Track::TYPE_AUDIO); if (track == NULL) { fprintf(stderr, "--audio option specified, but no audio track found\n"); return 1; } Options.track_filter = track->GetId(); } else if (Options.video_only) { AP4_Track* track = movie->GetTrack(AP4_Track::TYPE_VIDEO); if (track == NULL) { fprintf(stderr, "--video option specified, but no video track found\n"); return 1; } Options.track_filter = track->GetId(); } else if (Options.track_id) { AP4_Track* track = movie->GetTrack(Options.track_id); if (track == NULL) { fprintf(stderr, "--track-id option specified, but no such track found\n"); return 1; } Options.track_filter = track->GetId(); } // save the init segment AP4_ByteStream* output = NULL; result = AP4_FileByteStream::Create(Options.init_segment_name, AP4_FileByteStream::STREAM_MODE_WRITE, output); if (AP4_FAILED(result)) { fprintf(stderr, "ERROR: cannot open output file (%d)\n", result); return 1; } AP4_FtypAtom* ftyp = file->GetFileType(); if (ftyp) { result = ftyp->Write(*output); if (AP4_FAILED(result)) { fprintf(stderr, "ERROR: cannot write ftyp segment (%d)\n", result); return 1; } } if (Options.track_filter) { AP4_MoovAtom* moov = movie->GetMoovAtom(); // only keep the 'trak' atom that we need AP4_List<AP4_Atom>::Item* child = moov->GetChildren().FirstItem(); while (child) { AP4_Atom* atom = child->GetData(); child = child->GetNext(); if (atom->GetType() == AP4_ATOM_TYPE_TRAK) { AP4_TrakAtom* trak = (AP4_TrakAtom*)atom; AP4_TkhdAtom* tkhd = (AP4_TkhdAtom*)trak->GetChild(AP4_ATOM_TYPE_TKHD); if (tkhd && tkhd->GetTrackId() != Options.track_filter) { atom->Detach(); delete atom; } } } // only keep the 'trex' atom that we need AP4_ContainerAtom* mvex = AP4_DYNAMIC_CAST(AP4_ContainerAtom, moov->GetChild(AP4_ATOM_TYPE_MVEX)); if (mvex) { child = mvex->GetChildren().FirstItem(); while (child) { AP4_Atom* atom = child->GetData(); child = child->GetNext(); if (atom->GetType() == AP4_ATOM_TYPE_TREX) { AP4_TrexAtom* trex = AP4_DYNAMIC_CAST(AP4_TrexAtom, atom); if (trex && trex->GetTrackId() != Options.track_filter) { atom->Detach(); delete atom; } } } } } result = movie->GetMoovAtom()->Write(*output); if (AP4_FAILED(result)) { fprintf(stderr, "ERROR: cannot write init segment (%d)\n", result); return 1; } AP4_Atom* atom = NULL; unsigned int track_id = 0; for (;!Options.init_only;) { // process the next atom result = AP4_DefaultAtomFactory::Instance.CreateAtomFromStream(*input, atom); if (AP4_FAILED(result)) break; if (atom->GetType() == AP4_ATOM_TYPE_MOOF) { AP4_ContainerAtom* moof = AP4_DYNAMIC_CAST(AP4_ContainerAtom, atom); unsigned int traf_count = 0; AP4_ContainerAtom* traf = NULL; do { traf = AP4_DYNAMIC_CAST(AP4_ContainerAtom, moof->GetChild(AP4_ATOM_TYPE_TRAF, traf_count)); if (traf == NULL) break; AP4_TfhdAtom* tfhd = AP4_DYNAMIC_CAST(AP4_TfhdAtom, traf->GetChild(AP4_ATOM_TYPE_TFHD)); if (tfhd == NULL) { fprintf(stderr, "ERROR: invalid media format\n"); return 1; } track_id = tfhd->GetTrackId(); traf_count++; } while (traf); // check if this fragment has more than one traf if (traf_count > 1) { if (Options.audio_only) { fprintf(stderr, "ERROR: --audio option incompatible with multi-track fragments"); return 1; } if (Options.video_only) { fprintf(stderr, "ERROR: --video option incompatible with multi-track fragments"); return 1; } track_id = 0; } // open a new file for this fragment if (output) { output->Release(); output = NULL; } char segment_name[4096]; if (Options.track_filter == 0 || Options.track_filter == track_id) { AP4_UI64 p[2] = {0,0}; unsigned int params_len = strlen(Options.pattern_params); for (unsigned int i=0; i<params_len; i++) { if (Options.pattern_params[i] == 'I') { p[i] = track_id; } else if (Options.pattern_params[i] == 'N') { p[i] = NextFragmentIndex(track_id)+Options.start_number; } } switch (params_len) { case 1: sprintf(segment_name, Options.media_segment_name, p[0]); break; case 2: sprintf(segment_name, Options.media_segment_name, p[0], p[1]); break; default: segment_name[0] = 0; break; } result = AP4_FileByteStream::Create(segment_name, AP4_FileByteStream::STREAM_MODE_WRITE, output); if (AP4_FAILED(result)) { fprintf(stderr, "ERROR: cannot open output file (%d)\n", result); return 1; } } } // write the atom if (output && atom->GetType() != AP4_ATOM_TYPE_MFRA) { atom->Write(*output); } delete atom; } // cleanup delete file; if (input) input->Release(); if (output) output->Release(); return 0; }
/*---------------------------------------------------------------------- | AP4_Processor::Process +---------------------------------------------------------------------*/ AP4_Result AP4_Processor::Process(AP4_ByteStream& input, AP4_ByteStream& output, AP4_ByteStream* fragments, ProgressListener* listener, AP4_AtomFactory& atom_factory) { // read all atoms. // keep all atoms except [mdat] // keep a ref to [moov] // put [moof] atoms in a separate list AP4_AtomParent top_level; AP4_MoovAtom* moov = NULL; AP4_ContainerAtom* mfra = NULL; AP4_SidxAtom* sidx = NULL; AP4_List<AP4_AtomLocator> frags; AP4_UI64 stream_offset = 0; bool in_fragments = false; unsigned int sidx_count = 0; for (AP4_Atom* atom = NULL; AP4_SUCCEEDED(atom_factory.CreateAtomFromStream(input, atom)); input.Tell(stream_offset)) { if (atom->GetType() == AP4_ATOM_TYPE_MDAT) { delete atom; continue; } else if (atom->GetType() == AP4_ATOM_TYPE_MOOV) { moov = AP4_DYNAMIC_CAST(AP4_MoovAtom, atom); if (fragments) break; } else if (atom->GetType() == AP4_ATOM_TYPE_MFRA) { mfra = AP4_DYNAMIC_CAST(AP4_ContainerAtom, atom); continue; } else if (atom->GetType() == AP4_ATOM_TYPE_SIDX) { // don't keep the index, it is likely to be invalidated, we will recompute it later ++sidx_count; if (sidx == NULL) { sidx = AP4_DYNAMIC_CAST(AP4_SidxAtom, atom); } else { delete atom; continue; } } else if (atom->GetType() == AP4_ATOM_TYPE_SSIX) { // don't keep the index, it is likely to be invalidated delete atom; continue; } else if (!fragments && (in_fragments || atom->GetType() == AP4_ATOM_TYPE_MOOF)) { in_fragments = true; frags.Add(new AP4_AtomLocator(atom, stream_offset)); break; } top_level.AddChild(atom); } // check that we have at most one sidx (we can't deal with multi-sidx streams here if (sidx_count > 1) { top_level.RemoveChild(sidx); delete sidx; sidx = NULL; } // if we have a fragments stream, get the fragment locators from there if (fragments) { stream_offset = 0; for (AP4_Atom* atom = NULL; AP4_SUCCEEDED(atom_factory.CreateAtomFromStream(*fragments, atom)); fragments->Tell(stream_offset)) { if (atom->GetType() == AP4_ATOM_TYPE_MDAT) { delete atom; continue; } frags.Add(new AP4_AtomLocator(atom, stream_offset)); } } // initialize the processor AP4_Result result = Initialize(top_level, input); if (AP4_FAILED(result)) return result; // process the tracks if we have a moov atom AP4_Array<AP4_SampleLocator> locators; AP4_Cardinal track_count = 0; AP4_List<AP4_TrakAtom>* trak_atoms = NULL; AP4_LargeSize mdat_payload_size = 0; AP4_SampleCursor* cursors = NULL; if (moov) { // build an array of track sample locators trak_atoms = &moov->GetTrakAtoms(); track_count = trak_atoms->ItemCount(); cursors = new AP4_SampleCursor[track_count]; m_TrackData.SetItemCount(track_count); m_StreamData.SetItemCount(1); m_StreamData[0].stream = &input; unsigned int index = 0; for (AP4_List<AP4_TrakAtom>::Item* item = trak_atoms->FirstItem(); item; item=item->GetNext()) { AP4_TrakAtom* trak = item->GetData(); // find the stsd atom AP4_ContainerAtom* stbl = AP4_DYNAMIC_CAST(AP4_ContainerAtom, trak->FindChild("mdia/minf/stbl")); if (stbl == NULL) continue; // see if there's an external data source for this track AP4_ByteStream* trak_data_stream = &input; for (AP4_List<ExternalTrackData>::Item* ditem = m_ExternalTrackData.FirstItem(); ditem; ditem=ditem->GetNext()) { ExternalTrackData* tdata = ditem->GetData(); if (tdata->m_TrackId == trak->GetId()) { trak_data_stream = tdata->m_MediaData; break; } } AP4_ContainerAtom *mvex = AP4_DYNAMIC_CAST(AP4_ContainerAtom, moov->GetChild(AP4_ATOM_TYPE_MVEX)); AP4_TrexAtom* trex = NULL; if (mvex) { for (AP4_List<AP4_Atom>::Item* item = mvex->GetChildren().FirstItem(); item; item = item->GetNext()) { AP4_Atom* atom = item->GetData(); if (atom->GetType() == AP4_ATOM_TYPE_TREX) { trex = AP4_DYNAMIC_CAST(AP4_TrexAtom, atom); if (trex && trex->GetTrackId() == trak->GetId()) break; trex = NULL; } } } // create the track handler m_TrackData[index].track_handler = CreateTrackHandler(trak, trex); m_TrackData[index].new_id = trak->GetId(); cursors[index].m_Locator.m_TrakIndex = index; cursors[index].m_Locator.m_SampleTable = new AP4_AtomSampleTable(stbl, *trak_data_stream); cursors[index].m_Locator.m_SampleIndex = 0; cursors[index].m_Locator.m_ChunkIndex = 0; if (cursors[index].m_Locator.m_SampleTable->GetSampleCount()) { cursors[index].m_Locator.m_SampleTable->GetSample(0, cursors[index].m_Locator.m_Sample); } else { cursors[index].m_EndReached = true; } index++; } // figure out the layout of the chunks for (;;) { // see which is the next sample to write AP4_UI64 min_offset = (AP4_UI64)(-1); int cursor = -1; for (unsigned int i=0; i<track_count; i++) { if (!cursors[i].m_EndReached && cursors[i].m_Locator.m_Sample.GetOffset() <= min_offset) { min_offset = cursors[i].m_Locator.m_Sample.GetOffset(); cursor = i; } } // stop if all cursors are exhausted if (cursor == -1) break; // append this locator to the layout list AP4_SampleLocator& locator = cursors[cursor].m_Locator; locators.Append(locator); // move the cursor to the next sample locator.m_SampleIndex++; if (locator.m_SampleIndex == locator.m_SampleTable->GetSampleCount()) { // mark this track as completed cursors[cursor].m_EndReached = true; } else { // get the next sample info locator.m_SampleTable->GetSample(locator.m_SampleIndex, locator.m_Sample); AP4_Ordinal skip, sdesc; locator.m_SampleTable->GetChunkForSample(locator.m_SampleIndex, locator.m_ChunkIndex, skip, sdesc); } } // update the stbl atoms and compute the mdat size int current_track = -1; int current_chunk = -1; AP4_Position current_chunk_offset = 0; AP4_Size current_chunk_size = 0; for (AP4_Ordinal i=0; i<locators.ItemCount(); i++) { AP4_SampleLocator& locator = locators[i]; if ((int)locator.m_TrakIndex != current_track || (int)locator.m_ChunkIndex != current_chunk) { // start a new chunk for this track current_chunk_offset += current_chunk_size; current_chunk_size = 0; current_track = locator.m_TrakIndex; current_chunk = locator.m_ChunkIndex; locator.m_SampleTable->SetChunkOffset(locator.m_ChunkIndex, current_chunk_offset); } AP4_Size sample_size; TrackHandler* handler = m_TrackData[locator.m_TrakIndex].track_handler; if (handler) { sample_size = handler->GetProcessedSampleSize(locator.m_Sample); locator.m_SampleTable->SetSampleSize(locator.m_SampleIndex, sample_size); } else { sample_size = locator.m_Sample.GetSize(); } current_chunk_size += sample_size; mdat_payload_size += sample_size; } // process the tracks (ex: sample descriptions processing) for (AP4_Ordinal i=0; i<track_count; i++) { TrackHandler* handler = m_TrackData[i].track_handler; if (handler) handler->ProcessTrack(); } } // finalize the processor Finalize(top_level); if (!fragments) { // calculate the size of all atoms combined AP4_UI64 atoms_size = 0; top_level.GetChildren().Apply(AP4_AtomSizeAdder(atoms_size)); // see if we need a 64-bit or 32-bit mdat AP4_Size mdat_header_size = AP4_ATOM_HEADER_SIZE; if (mdat_payload_size+mdat_header_size > 0xFFFFFFFF) { // we need a 64-bit size mdat_header_size += 8; } // adjust the chunk offsets for (AP4_Ordinal i=0; i<track_count; i++) { AP4_TrakAtom* trak; trak_atoms->Get(i, trak); trak->AdjustChunkOffsets(atoms_size+mdat_header_size); } // write all atoms top_level.GetChildren().Apply(AP4_AtomListWriter(output)); // write mdat header if (mdat_payload_size) { if (mdat_header_size == AP4_ATOM_HEADER_SIZE) { // 32-bit size output.WriteUI32((AP4_UI32)(mdat_header_size+mdat_payload_size)); output.WriteUI32(AP4_ATOM_TYPE_MDAT); } else { // 64-bit size output.WriteUI32(1); output.WriteUI32(AP4_ATOM_TYPE_MDAT); output.WriteUI64(mdat_header_size+mdat_payload_size); } } } // write the samples if (moov) { if (!fragments) { #if defined(AP4_DEBUG) AP4_Position before; output.Tell(before); #endif AP4_Sample sample; AP4_DataBuffer data_in; AP4_DataBuffer data_out; for (unsigned int i=0; i<locators.ItemCount(); i++) { AP4_SampleLocator& locator = locators[i]; locator.m_Sample.ReadData(data_in); TrackHandler* handler = m_TrackData[locator.m_TrakIndex].track_handler; if (handler) { result = handler->ProcessSample(data_in, data_out); if (AP4_FAILED(result)) return result; output.Write(data_out.GetData(), data_out.GetDataSize()); } else { output.Write(data_in.GetData(), data_in.GetDataSize()); } // notify the progress listener if (listener) { listener->OnProgress(i+1, locators.ItemCount()); } } #if defined(AP4_DEBUG) AP4_Position after; output.Tell(after); AP4_ASSERT(after-before == mdat_payload_size); #endif } else m_StreamData[0].stream = fragments; // find the position of the sidx atom AP4_Position sidx_position = 0; if (sidx) { for (AP4_List<AP4_Atom>::Item* item = top_level.GetChildren().FirstItem(); item; item = item->GetNext()) { AP4_Atom* atom = item->GetData(); if (atom->GetType() == AP4_ATOM_TYPE_SIDX) { break; } sidx_position += atom->GetSize(); } } // process the fragments, if any AP4_Array<AP4_Position> moof_offsets, mdat_offsets; moof_offsets.SetItemCount(1); mdat_offsets.SetItemCount(1); while (frags.ItemCount() > 0) { for (AP4_List<AP4_AtomLocator>::Item *locator(frags.FirstItem()); locator; locator = locator->GetNext()) { AP4_ContainerAtom *moof(AP4_DYNAMIC_CAST(AP4_ContainerAtom, locator->GetData()->m_Atom)); moof_offsets[0] = locator->GetData()->m_Offset; mdat_offsets[0] = moof_offsets[0] + moof->GetSize() + AP4_ATOM_HEADER_SIZE; result = ProcessFragment(moof, sidx, sidx_position, output, moof_offsets, mdat_offsets); if (AP4_FAILED(result)) return result; } frags.DeleteReferences(); AP4_Atom* atom = NULL; input.Tell(stream_offset); if (AP4_SUCCEEDED(atom_factory.CreateAtomFromStream(input, atom))) { if (atom->GetType() == AP4_ATOM_TYPE_MOOF) frags.Add(new AP4_AtomLocator(atom, stream_offset)); else delete atom; } } // update the mfra if we have one if (mfra) { for (AP4_List<AP4_Atom>::Item* mfra_item = mfra->GetChildren().FirstItem(); mfra_item; mfra_item = mfra_item->GetNext()) { if (mfra_item->GetData()->GetType() != AP4_ATOM_TYPE_TFRA) continue; AP4_TfraAtom* tfra = AP4_DYNAMIC_CAST(AP4_TfraAtom, mfra_item->GetData()); if (tfra == NULL) continue; AP4_Array<AP4_TfraAtom::Entry>& entries = tfra->GetEntries(); AP4_Cardinal entry_count = entries.ItemCount(); for (unsigned int i = 0; i<entry_count; i++) { entries[i].m_MoofOffset = FindFragmentMapEntry(entries[i].m_MoofOffset); } } } // update and re-write the sidx if we have one if (sidx && sidx_position) { AP4_Position where = 0; output.Tell(where); output.Seek(sidx_position); result = sidx->Write(output); if (AP4_FAILED(result)) return result; output.Seek(where); } if (!fragments) { // write the mfra atom at the end if we have one if (mfra) { mfra->Write(output); } } // cleanup for (AP4_Ordinal i=0; i<track_count; i++) delete cursors[i].m_Locator.m_SampleTable; m_TrackData.Clear(); delete[] cursors; } // cleanup frags.DeleteReferences(); delete mfra; return AP4_SUCCESS; }
/*---------------------------------------------------------------------- | AP4_Movie::ProcessMoof +---------------------------------------------------------------------*/ void AP4_Movie::ProcessMoof(AP4_ContainerAtom* moof, AP4_ByteStream& stream) { if (moof) { AP4_Offset offset = 0; stream.Tell(offset); AP4_Offset moof_offset = offset - moof->GetSize(); AP4_Offset mdat_payload_offset = offset + 8; AP4_MfhdAtom* mfhd = AP4_DYNAMIC_CAST(AP4_MfhdAtom, moof->GetChild(AP4_ATOM_TYPE_MFHD)); if (mfhd) { for (AP4_List<AP4_Atom>::Item* item = moof->GetChildren().FirstItem(); item; item = item->GetNext()) { AP4_Atom* atom = item->GetData(); if (atom->GetType() == AP4_ATOM_TYPE_TRAF) { AP4_ContainerAtom* traf = AP4_DYNAMIC_CAST(AP4_ContainerAtom, atom); if (traf) { AP4_TfhdAtom* tfhd = AP4_DYNAMIC_CAST(AP4_TfhdAtom, traf->GetChild(AP4_ATOM_TYPE_TFHD)); if (!tfhd) { continue; } AP4_Track* track = GetTrack(tfhd->GetTrackId()); if (!track) { continue; } AP4_TfdtAtom* tfdt = AP4_DYNAMIC_CAST(AP4_TfdtAtom, traf->GetChild(AP4_ATOM_TYPE_TFDT)); AP4_TrexAtom* trex = NULL; AP4_ContainerAtom* mvex = AP4_DYNAMIC_CAST(AP4_ContainerAtom, m_MoovAtom->GetChild(AP4_ATOM_TYPE_MVEX)); if (mvex) { for (AP4_List<AP4_Atom>::Item* child_item = mvex->GetChildren().FirstItem(); child_item; child_item = child_item->GetNext()) { AP4_Atom* child_atom = child_item->GetData(); if (child_atom->GetType() == AP4_ATOM_TYPE_TREX) { trex = AP4_DYNAMIC_CAST(AP4_TrexAtom, child_atom); if (trex && trex->GetTrackId() == tfhd->GetTrackId()) break; trex = NULL; } } } AP4_FragmentSampleTable* sampleTable = track->GetFragmentSampleTable(); AP4_Cardinal sample_count = 0; for (AP4_List<AP4_Atom>::Item* child_item = traf->GetChildren().FirstItem(); child_item; child_item = child_item->GetNext()) { AP4_Atom* child_atom = child_item->GetData(); if (child_atom->GetType() == AP4_ATOM_TYPE_TRUN) { AP4_TrunAtom* trun = AP4_DYNAMIC_CAST(AP4_TrunAtom, child_atom); if (trun) { sample_count += trun->GetEntries().ItemCount(); } } } if (!sample_count) { return; } if (sampleTable->GetSampleCount() == 0) { track->CreateFragmentFromStdSamples(); } if (AP4_FAILED(sampleTable->EnsureCapacity(sample_count + sampleTable->GetSampleCount()))) { return; } AP4_UI64 dts_origin = tfdt ? tfdt->GetBaseMediaDecodeTime() : 0; for (AP4_List<AP4_Atom>::Item* child_item = traf->GetChildren().FirstItem(); child_item; child_item = child_item->GetNext()) { AP4_Atom* child_atom = child_item->GetData(); if (child_atom->GetType() == AP4_ATOM_TYPE_TRUN) { AP4_TrunAtom* trun = AP4_DYNAMIC_CAST(AP4_TrunAtom, child_atom); if (trun) { sampleTable->AddTrun(trun, tfhd, trex, stream, dts_origin, moof_offset, mdat_payload_offset); } } } } } } } } }