AP4_Result
AP4_File_GetFileType(AP4_File* self,
AP4_UI32* major_brand,
AP4_UI32* minor_version,
AP4_Cardinal* compatible_brand_count)
{
AP4_FtypAtom* ftyp = self->GetFileType();
if (!ftyp) return AP4_FAILURE;
if (major_brand) *major_brand = ftyp->GetMajorBrand();
if (minor_version) *minor_version = ftyp->GetMinorVersion();
if (compatible_brand_count) {
*compatible_brand_count = ftyp->GetCompatibleBrands().ItemCount();
}
return AP4_SUCCESS;
}
/*----------------------------------------------------------------------
| 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_OmaDcfEncryptingProcessor::Initialize
+---------------------------------------------------------------------*/
AP4_Result
AP4_OmaDcfEncryptingProcessor::Initialize(AP4_AtomParent& top_level,
AP4_ByteStream& /*stream*/,
AP4_Processor::ProgressListener* /*listener*/)
{
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 OMA compatible brand if it is not already there
if (!ftyp->HasCompatibleBrand(AP4_OMA_DCF_BRAND_OPF2)) {
compatible_brands.Append(AP4_OMA_DCF_BRAND_OPF2);
}
// create a replacement
AP4_FtypAtom* new_ftyp = new AP4_FtypAtom(ftyp->GetMajorBrand(),
ftyp->GetMinorVersion(),
&compatible_brands[0],
compatible_brands.ItemCount());
delete ftyp;
ftyp = new_ftyp;
} else {
AP4_UI32 opf2 = AP4_OMA_DCF_BRAND_OPF2;
ftyp = new AP4_FtypAtom(AP4_FTYP_BRAND_ISOM, 0, &opf2, 1);
}
// insert the ftyp atom as the first child
return top_level.AddChild(ftyp, 0);
}
/*----------------------------------------------------------------------
| Fragment
+---------------------------------------------------------------------*/
static void
Fragment(AP4_File& input_file,
AP4_ByteStream& output_stream,
AP4_Array<TrackCursor*>& cursors,
unsigned int fragment_duration,
AP4_UI32 timescale,
AP4_UI32 track_id,
bool create_segment_index)
{
AP4_List<FragmentInfo> fragments;
TrackCursor* index_cursor = NULL;
AP4_Result result;
AP4_Movie* input_movie = input_file.GetMovie();
if (input_movie == NULL) {
fprintf(stderr, "ERROR: no moov found in the input file\n");
return;
}
// create the output file object
AP4_Movie* output_movie = new AP4_Movie(1000);
// create an mvex container
AP4_ContainerAtom* mvex = new AP4_ContainerAtom(AP4_ATOM_TYPE_MVEX);
AP4_MehdAtom* mehd = new AP4_MehdAtom(0);
mvex->AddChild(mehd);
// add an output track for each track in the input file
for (unsigned int i=0; i<cursors.ItemCount(); i++) {
AP4_Track* track = cursors[i]->m_Track;
// skip non matching tracks if we have a selector
if (track_id && track->GetId() != track_id) {
continue;
}
result = cursors[i]->Init();
if (AP4_FAILED(result)) {
fprintf(stderr, "ERROR: failed to init sample cursor (%d), skipping track %d\n", result, track->GetId());
return;
}
// create a sample table (with no samples) to hold the sample description
AP4_SyntheticSampleTable* sample_table = new AP4_SyntheticSampleTable();
for (unsigned int j=0; j<track->GetSampleDescriptionCount(); j++) {
AP4_SampleDescription* sample_description = track->GetSampleDescription(j);
sample_table->AddSampleDescription(sample_description, false);
}
// create the track
AP4_Track* output_track = new AP4_Track(sample_table,
track->GetId(),
timescale?timescale:1000,
AP4_ConvertTime(track->GetDuration(),
input_movie->GetTimeScale(),
timescale?timescale:1000),
timescale?timescale:track->GetMediaTimeScale(),
0,//track->GetMediaDuration(),
track);
output_movie->AddTrack(output_track);
// add a trex entry to the mvex container
AP4_TrexAtom* trex = new AP4_TrexAtom(track->GetId(),
1,
0,
0,
0);
mvex->AddChild(trex);
}
// select the anchor cursor
TrackCursor* anchor_cursor = NULL;
for (unsigned int i=0; i<cursors.ItemCount(); i++) {
if (cursors[i]->m_Track->GetId() == track_id) {
anchor_cursor = cursors[i];
}
}
if (anchor_cursor == NULL) {
for (unsigned int i=0; i<cursors.ItemCount(); i++) {
// use this as the anchor track if it is the first video track
if (cursors[i]->m_Track->GetType() == AP4_Track::TYPE_VIDEO) {
anchor_cursor = cursors[i];
break;
}
}
}
if (anchor_cursor == NULL) {
// no video track to anchor with, pick the first audio track
for (unsigned int i=0; i<cursors.ItemCount(); i++) {
if (cursors[i]->m_Track->GetType() == AP4_Track::TYPE_AUDIO) {
anchor_cursor = cursors[i];
break;
}
}
// no audio track to anchor with, pick the first subtitles track
for (unsigned int i=0; i<cursors.ItemCount(); i++) {
if (cursors[i]->m_Track->GetType() == AP4_Track::TYPE_SUBTITLES) {
anchor_cursor = cursors[i];
break;
}
}
}
if (anchor_cursor == NULL) {
// this shoudl never happen
fprintf(stderr, "ERROR: no anchor track\n");
return;
}
if (create_segment_index) {
index_cursor = anchor_cursor;
}
if (Options.debug) {
printf("Using track ID %d as anchor\n", anchor_cursor->m_Track->GetId());
}
// update the mehd duration
mehd->SetDuration(output_movie->GetDuration());
// add the mvex container to the moov container
output_movie->GetMoovAtom()->AddChild(mvex);
// compute all the fragments
unsigned int sequence_number = 1;
for(;;) {
TrackCursor* cursor = NULL;
// pick the first track with a fragment index lower than the anchor's
for (unsigned int i=0; i<cursors.ItemCount(); i++) {
if (track_id && cursors[i]->m_Track->GetId() != track_id) continue;
if (cursors[i]->m_Eos) continue;
if (cursors[i]->m_FragmentIndex < anchor_cursor->m_FragmentIndex) {
cursor = cursors[i];
break;
}
}
// check if we found a non-anchor cursor to use
if (cursor == NULL) {
// the anchor should be used in this round, check if we can use it
if (anchor_cursor->m_Eos) {
// the anchor is done, pick a new anchor unless we need to trim
anchor_cursor = NULL;
if (!Options.trim) {
for (unsigned int i=0; i<cursors.ItemCount(); i++) {
if (track_id && cursors[i]->m_Track->GetId() != track_id) continue;
if (cursors[i]->m_Eos) continue;
if (anchor_cursor == NULL ||
cursors[i]->m_Track->GetType() == AP4_Track::TYPE_VIDEO ||
cursors[i]->m_Track->GetType() == AP4_Track::TYPE_AUDIO) {
anchor_cursor = cursors[i];
if (Options.debug) {
printf("+++ New anchor: Track ID %d\n", anchor_cursor->m_Track->GetId());
}
}
}
}
}
cursor = anchor_cursor;
}
if (cursor == NULL) break; // all done
// decide how many samples go into this fragment
AP4_UI64 target_dts;
if (cursor == anchor_cursor) {
// compute the current dts in milliseconds
AP4_UI64 anchor_dts_ms = AP4_ConvertTime(cursor->m_Sample.GetDts(),
cursor->m_Track->GetMediaTimeScale(),
1000);
// round to the nearest multiple of fragment_duration
AP4_UI64 anchor_position = (anchor_dts_ms + (fragment_duration/2))/fragment_duration;
// pick the next fragment_duration multiple at our target
target_dts = AP4_ConvertTime(fragment_duration*(anchor_position+1),
1000,
cursor->m_Track->GetMediaTimeScale());
} else {
target_dts = AP4_ConvertTime(anchor_cursor->m_Sample.GetDts(),
anchor_cursor->m_Track->GetMediaTimeScale(),
cursor->m_Track->GetMediaTimeScale());
if (target_dts <= cursor->m_Sample.GetDts()) {
// we must be at the end, past the last anchor sample, just use the target duration
target_dts = AP4_ConvertTime(fragment_duration*(cursor->m_FragmentIndex+1),
1000,
cursor->m_Track->GetMediaTimeScale());
if (target_dts <= cursor->m_Sample.GetDts()) {
// we're still behind, there may have been an alignment/rounding error, just advance by one segment duration
target_dts = cursor->m_Sample.GetDts()+AP4_ConvertTime(fragment_duration,
1000,
cursor->m_Track->GetMediaTimeScale());
}
}
}
unsigned int end_sample_index = cursor->m_Samples->GetSampleCount();
AP4_UI64 smallest_diff = (AP4_UI64)(0xFFFFFFFFFFFFFFFFULL);
AP4_Sample sample;
for (unsigned int i=cursor->m_SampleIndex+1; i<=cursor->m_Samples->GetSampleCount(); i++) {
AP4_UI64 dts;
if (i < cursor->m_Samples->GetSampleCount()) {
result = cursor->m_Samples->GetSample(i, sample);
if (AP4_FAILED(result)) {
fprintf(stderr, "ERROR: failed to get sample %d (%d)\n", i, result);
return;
}
if (!sample.IsSync()) continue; // only look for sync samples
dts = sample.GetDts();
} else {
result = cursor->m_Samples->GetSample(i-1, sample);
if (AP4_FAILED(result)) {
fprintf(stderr, "ERROR: failed to get sample %d (%d)\n", i-1, result);
return;
}
dts = sample.GetDts()+sample.GetDuration();
}
AP4_SI64 diff = dts-target_dts;
AP4_UI64 abs_diff = diff<0?-diff:diff;
if (abs_diff < smallest_diff) {
// this sample is the closest to the target so far
end_sample_index = i;
smallest_diff = abs_diff;
}
if (diff >= 0) {
// this sample is past the target, it is not going to get any better, stop looking
break;
}
}
if (cursor->m_Eos) continue;
if (Options.debug) {
if (cursor == anchor_cursor) {
printf("====");
} else {
printf("----");
}
printf(" Track ID %d - dts=%lld, target=%lld, start=%d, end=%d/%d\n",
cursor->m_Track->GetId(),
cursor->m_Sample.GetDts(),
target_dts,
cursor->m_SampleIndex,
end_sample_index,
cursor->m_Track->GetSampleCount());
}
// emit a fragment for the selected track
if (Options.verbosity > 1) {
printf("fragment: track ID %d ", cursor->m_Track->GetId());
}
// decide which sample description index to use
// (this is not very sophisticated, we only look at the sample description
// index of the first sample in the group, which may not be correct. This
// should be fixed later)
unsigned int sample_desc_index = cursor->m_Sample.GetDescriptionIndex();
unsigned int tfhd_flags = AP4_TFHD_FLAG_DEFAULT_BASE_IS_MOOF;
if (sample_desc_index > 0) {
tfhd_flags |= AP4_TFHD_FLAG_SAMPLE_DESCRIPTION_INDEX_PRESENT;
}
if (cursor->m_Track->GetType() == AP4_Track::TYPE_VIDEO) {
tfhd_flags |= AP4_TFHD_FLAG_DEFAULT_SAMPLE_FLAGS_PRESENT;
}
// setup the moof structure
AP4_ContainerAtom* moof = new AP4_ContainerAtom(AP4_ATOM_TYPE_MOOF);
AP4_MfhdAtom* mfhd = new AP4_MfhdAtom(sequence_number++);
moof->AddChild(mfhd);
AP4_ContainerAtom* traf = new AP4_ContainerAtom(AP4_ATOM_TYPE_TRAF);
AP4_TfhdAtom* tfhd = new AP4_TfhdAtom(tfhd_flags,
cursor->m_Track->GetId(),
0,
sample_desc_index+1,
0,
0,
0);
if (tfhd_flags & AP4_TFHD_FLAG_DEFAULT_SAMPLE_FLAGS_PRESENT) {
tfhd->SetDefaultSampleFlags(0x1010000); // sample_is_non_sync_sample=1, sample_depends_on=1 (not I frame)
}
traf->AddChild(tfhd);
if (!Options.no_tfdt) {
AP4_TfdtAtom* tfdt = new AP4_TfdtAtom(1, cursor->m_Timestamp);
traf->AddChild(tfdt);
}
AP4_UI32 trun_flags = AP4_TRUN_FLAG_DATA_OFFSET_PRESENT |
AP4_TRUN_FLAG_SAMPLE_DURATION_PRESENT |
AP4_TRUN_FLAG_SAMPLE_SIZE_PRESENT;
AP4_UI32 first_sample_flags = 0;
if (cursor->m_Track->GetType() == AP4_Track::TYPE_VIDEO) {
trun_flags |= AP4_TRUN_FLAG_FIRST_SAMPLE_FLAGS_PRESENT;
first_sample_flags = 0x2000000; // sample_depends_on=2 (I frame)
}
AP4_TrunAtom* trun = new AP4_TrunAtom(trun_flags, 0, first_sample_flags);
traf->AddChild(trun);
moof->AddChild(traf);
// create a new FragmentInfo object to store the fragment details
FragmentInfo* fragment = new FragmentInfo(cursor->m_Samples, cursor->m_Tfra, cursor->m_Timestamp, moof);
fragments.Add(fragment);
// add samples to the fragment
unsigned int sample_count = 0;
AP4_Array<AP4_TrunAtom::Entry> trun_entries;
fragment->m_MdatSize = AP4_ATOM_HEADER_SIZE;
for (;;) {
// if we have one non-zero CTS delta, we'll need to express it
if (cursor->m_Sample.GetCtsDelta()) {
trun->SetFlags(trun->GetFlags() | AP4_TRUN_FLAG_SAMPLE_COMPOSITION_TIME_OFFSET_PRESENT);
}
// add one sample
trun_entries.SetItemCount(sample_count+1);
AP4_TrunAtom::Entry& trun_entry = trun_entries[sample_count];
trun_entry.sample_duration = timescale?
(AP4_UI32)AP4_ConvertTime(cursor->m_Sample.GetDuration(),
cursor->m_Track->GetMediaTimeScale(),
timescale):
cursor->m_Sample.GetDuration();
trun_entry.sample_size = cursor->m_Sample.GetSize();
trun_entry.sample_composition_time_offset = timescale?
(AP4_UI32)AP4_ConvertTime(cursor->m_Sample.GetCtsDelta(),
cursor->m_Track->GetMediaTimeScale(),
timescale):
cursor->m_Sample.GetCtsDelta();
fragment->m_SampleIndexes.SetItemCount(sample_count+1);
fragment->m_SampleIndexes[sample_count] = cursor->m_SampleIndex;
fragment->m_MdatSize += trun_entry.sample_size;
fragment->m_Duration += trun_entry.sample_duration;
// next sample
cursor->m_Timestamp += trun_entry.sample_duration;
result = cursor->SetSampleIndex(cursor->m_SampleIndex+1);
if (AP4_FAILED(result)) {
fprintf(stderr, "ERROR: failed to get sample %d (%d)\n", cursor->m_SampleIndex+1, result);
return;
}
sample_count++;
if (cursor->m_Eos) {
if (Options.debug) {
printf("[Track ID %d has reached the end]\n", cursor->m_Track->GetId());
}
break;
}
if (cursor->m_SampleIndex >= end_sample_index) {
break; // done with this fragment
}
}
if (Options.verbosity > 1) {
printf(" %d samples\n", sample_count);
}
// update moof and children
trun->SetEntries(trun_entries);
trun->SetDataOffset((AP4_UI32)moof->GetSize()+AP4_ATOM_HEADER_SIZE);
// advance the cursor's fragment index
++cursor->m_FragmentIndex;
}
// write the ftyp atom
AP4_FtypAtom* ftyp = input_file.GetFileType();
if (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 compatible brand if it is not already there
if (!ftyp->HasCompatibleBrand(AP4_FILE_BRAND_ISO5)) {
compatible_brands.Append(AP4_FILE_BRAND_ISO5);
}
// create a replacement
AP4_FtypAtom* new_ftyp = new AP4_FtypAtom(ftyp->GetMajorBrand(),
ftyp->GetMinorVersion(),
&compatible_brands[0],
compatible_brands.ItemCount());
ftyp = new_ftyp;
} else {
AP4_UI32 compat = AP4_FILE_BRAND_ISO5;
ftyp = new AP4_FtypAtom(AP4_FTYP_BRAND_MP42, 0, &compat, 1);
}
ftyp->Write(output_stream);
delete ftyp;
// write the moov atom
output_movie->GetMoovAtom()->Write(output_stream);
// write the (not-yet fully computed) index if needed
AP4_SidxAtom* sidx = NULL;
AP4_Position sidx_position = 0;
output_stream.Tell(sidx_position);
if (create_segment_index) {
sidx = new AP4_SidxAtom(index_cursor->m_Track->GetId(),
index_cursor->m_Track->GetMediaTimeScale(),
0,
0);
// reserve space for the entries now, but they will be computed and updated later
sidx->SetReferenceCount(fragments.ItemCount());
sidx->Write(output_stream);
}
// write all fragments
for (AP4_List<FragmentInfo>::Item* item = fragments.FirstItem();
item;
item = item->GetNext()) {
FragmentInfo* fragment = item->GetData();
// remember the time and position of this fragment
output_stream.Tell(fragment->m_MoofPosition);
fragment->m_Tfra->AddEntry(fragment->m_Timestamp, fragment->m_MoofPosition);
// write the moof
fragment->m_Moof->Write(output_stream);
// write mdat
output_stream.WriteUI32(fragment->m_MdatSize);
output_stream.WriteUI32(AP4_ATOM_TYPE_MDAT);
AP4_DataBuffer sample_data;
AP4_Sample sample;
for (unsigned int i=0; i<fragment->m_SampleIndexes.ItemCount(); i++) {
// get the sample
result = fragment->m_Samples->GetSample(fragment->m_SampleIndexes[i], sample);
if (AP4_FAILED(result)) {
fprintf(stderr, "ERROR: failed to get sample %d (%d)\n", fragment->m_SampleIndexes[i], result);
return;
}
// read the sample data
result = sample.ReadData(sample_data);
if (AP4_FAILED(result)) {
fprintf(stderr, "ERROR: failed to read sample data for sample %d (%d)\n", fragment->m_SampleIndexes[i], result);
return;
}
// write the sample data
result = output_stream.Write(sample_data.GetData(), sample_data.GetDataSize());
if (AP4_FAILED(result)) {
fprintf(stderr, "ERROR: failed to write sample data (%d)\n", result);
return;
}
}
}
// update the index and re-write it if needed
if (create_segment_index) {
unsigned int segment_index = 0;
AP4_SidxAtom::Reference reference;
for (AP4_List<FragmentInfo>::Item* item = fragments.FirstItem();
item;
item = item->GetNext()) {
FragmentInfo* fragment = item->GetData();
reference.m_ReferencedSize = (AP4_UI32)(fragment->m_Moof->GetSize()+fragment->m_MdatSize);
reference.m_SubsegmentDuration = fragment->m_Duration;
reference.m_StartsWithSap = true;
sidx->SetReference(segment_index++, reference);
}
AP4_Position here = 0;
output_stream.Tell(here);
output_stream.Seek(sidx_position);
sidx->Write(output_stream);
output_stream.Seek(here);
delete sidx;
}
// create an mfra container and write out the index
AP4_ContainerAtom mfra(AP4_ATOM_TYPE_MFRA);
for (unsigned int i=0; i<cursors.ItemCount(); i++) {
if (track_id && cursors[i]->m_Track->GetId() != track_id) {
continue;
}
mfra.AddChild(cursors[i]->m_Tfra);
cursors[i]->m_Tfra = NULL;
}
AP4_MfroAtom* mfro = new AP4_MfroAtom((AP4_UI32)mfra.GetSize()+16);
mfra.AddChild(mfro);
result = mfra.Write(output_stream);
if (AP4_FAILED(result)) {
fprintf(stderr, "ERROR: failed to write 'mfra' (%d)\n", result);
return;
}
// cleanup
fragments.DeleteReferences();
for (unsigned int i=0; i<cursors.ItemCount(); i++) {
delete cursors[i];
}
for (AP4_List<FragmentInfo>::Item* item = fragments.FirstItem();
item;
item = item->GetNext()) {
FragmentInfo* fragment = item->GetData();
delete fragment->m_Moof;
}
delete output_movie;
}
/*----------------------------------------------------------------------
| 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;
// check that we have what we need
if (od_update == NULL || ipmp_update == NULL) {
delete od_track;
return AP4_ERROR_INVALID_FORMAT;
}
// process all the object descriptors in the od update
for (AP4_List<AP4_Descriptor>::Item* od_item = od_update->GetDescriptors().FirstItem();
od_item;
od_item = od_item->GetNext()) {
od = AP4_DYNAMIC_CAST(AP4_ObjectDescriptor, od_item->GetData());
if (od == NULL) continue;
// find which track this od references
AP4_EsIdRefDescriptor* es_id_ref;
es_id_ref = AP4_DYNAMIC_CAST(AP4_EsIdRefDescriptor, od->FindSubDescriptor(AP4_DESCRIPTOR_TAG_ES_ID_REF));
if (es_id_ref == NULL ||
es_id_ref->GetRefIndex() > track_references->GetTrackIds().ItemCount() ||
es_id_ref->GetRefIndex() == 0) {
continue;
}
AP4_UI32 track_id = track_references->GetTrackIds()[es_id_ref->GetRefIndex()-1];
SinfEntry* sinf_entry = NULL;
for (AP4_List<SinfEntry>::Item* sinf_entry_item = sinf_entries.FirstItem();
sinf_entry_item;
sinf_entry_item = sinf_entry_item->GetNext()) {
sinf_entry = sinf_entry_item->GetData();
if (sinf_entry->m_TrackId == track_id) {
break; // match
} else {
sinf_entry = NULL; // no match
}
}
if (sinf_entry == NULL) continue; // no matching entry
if (sinf_entry->m_Sinf != NULL) continue; // entry already populated
// see what ipmp descriptor this od points to
AP4_IpmpDescriptorPointer* ipmpd_pointer;
ipmpd_pointer = AP4_DYNAMIC_CAST(AP4_IpmpDescriptorPointer, od->FindSubDescriptor(AP4_DESCRIPTOR_TAG_IPMP_DESCRIPTOR_POINTER));
if (ipmpd_pointer == NULL) continue; // no pointer
// find the ipmp descriptor referenced by the pointer
AP4_IpmpDescriptor* ipmpd = NULL;
for (AP4_List<AP4_Descriptor>::Item* ipmpd_item = ipmp_update->GetDescriptors().FirstItem();
ipmpd_item;
ipmpd_item = ipmpd_item->GetNext()) {
// check that this descriptor is of the right type
ipmpd = AP4_DYNAMIC_CAST(AP4_IpmpDescriptor, ipmpd_item->GetData());
if (ipmpd == NULL || ipmpd->GetIpmpsType() != AP4_MARLIN_IPMPS_TYPE_MGSV) continue;
// check the descriptor id
if (ipmpd->GetDescriptorId() == ipmpd_pointer->GetDescriptorId()) {
break; // match
} else {
ipmpd = NULL; // no match
}
}
if (ipmpd == NULL) continue; // no matching entry
// parse the ipmp data into one or more 'sinf' atoms, and keep the one with the
// right type
AP4_MemoryByteStream* data = new AP4_MemoryByteStream(ipmpd->GetData().GetData(),
ipmpd->GetData().GetDataSize());
AP4_LargeSize bytes_available = ipmpd->GetData().GetDataSize();
do {
AP4_Atom* atom = NULL;
// setup the factory with a context so we can instantiate an 'schm'
// atom with a slightly different format than the standard 'schm'
AP4_AtomFactory* factory = &AP4_MarlinIpmpAtomFactory::Instance;
factory->PushContext(AP4_ATOM_TYPE('m','r','l','n'));
// parse the next atom in the stream
result = factory->CreateAtomFromStream(*data, bytes_available, atom);
factory->PopContext();
if (AP4_FAILED(result) || atom == NULL) break;
// check that what we have parsed is indeed an 'sinf' of the right type
if (atom->GetType() == AP4_ATOM_TYPE_SINF) {
AP4_ContainerAtom* sinf = AP4_DYNAMIC_CAST(AP4_ContainerAtom, atom);
AP4_SchmAtom* schm = AP4_DYNAMIC_CAST(AP4_SchmAtom, sinf->FindChild("schm"));
if (schm->GetSchemeType() == AP4_PROTECTION_SCHEME_TYPE_MARLIN_ACBC &&
schm->GetSchemeVersion() == 0x0100) {
// store the sinf in the entry for that track
sinf_entry->m_Sinf = sinf;
break;
}
}
delete atom;
} while (AP4_SUCCEEDED(result));
data->Release();
}
// remove the iods atom and the OD track if required
if (remove_od_data) {
od_trak->Detach();
delete od_trak;
iods->Detach();
delete iods;
}
// cleanup
delete od_track;
return AP4_SUCCESS;
}