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Bug Fix: CMAF DASH playback works
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- syntax error fixed
- removed unnecessary track id simplification
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@tegginamaniss @Thulinma
tegginamaniss authored and Thulinma committed Feb 11, 2022
1 parent e9d5920 commit ccee512
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Showing 2 changed files with 43 additions and 49 deletions.
54 changes: 21 additions & 33 deletions lib/cmaf.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -13,14 +13,6 @@ namespace CMAF{
return payloadSize;
}

size_t simplifiedTrackId(const DTSC::Meta & M, size_t idx) {
std::string type = M.getType(idx);
if (type == "video") {return 1;}
if (type == "audio") {return 2;}
if (type == "meta") {return 3;}
return idx;
}

std::string trackHeader(const DTSC::Meta &M, size_t track, bool simplifyTrackIds){
std::string tType = M.getType(track);

Expand All @@ -43,9 +35,6 @@ namespace CMAF{
MP4::TRAK trakBox;

MP4::TKHD tkhdBox(M, track);
if (simplifyTrackIds){
tkhdBox.setTrackID(simplifiedTrackId(M, track));
}
tkhdBox.setDuration(0);
trakBox.setContent(tkhdBox, 0);

Expand Down Expand Up @@ -87,7 +76,7 @@ namespace CMAF{
btrtBox.setAverageBitrate(M.getBps(track));
btrtBox.setMaxBitrate(M.getMaxBps(track));

sampleEntry.setBoxEntry(sampleEntry.getBoxEntryCount(),btrtBox);
sampleEntry.setBoxEntry(sampleEntry.getBoxEntryCount(), btrtBox);
stsdBox.setEntry(sampleEntry, 0);
}else if (tType == "audio"){
MP4::AudioSampleEntry sampleEntry(M, track);
Expand All @@ -96,7 +85,7 @@ namespace CMAF{
btrtBox.setAverageBitrate(M.getBps(track));
btrtBox.setMaxBitrate(M.getMaxBps(track));

sampleEntry.setBoxEntry(sampleEntry.getBoxEntryCount(),btrtBox);
sampleEntry.setBoxEntry(sampleEntry.getBoxEntryCount(), btrtBox);
stsdBox.setEntry(sampleEntry, 0);
}else if (tType == "meta"){
MP4::TextSampleEntry sampleEntry(M, track);
Expand Down Expand Up @@ -131,9 +120,6 @@ namespace CMAF{
}

MP4::TREX trexBox(track + 1);
if (simplifyTrackIds){
trexBox.setTrackID(simplifiedTrackId(M, track));
}
trexBox.setDefaultSampleDuration(1000);
mvexBox.setContent(trexBox, M.getVod() ? 1 : 0);

Expand All @@ -148,17 +134,21 @@ namespace CMAF{
MP4::SIDX sidxBox;
sidxBox.setReferenceID(track + 1);
sidxBox.setTimescale(1000);
sidxBox.setEarliestPresentationTime(keys.getTime(0) + parts.getOffset(0) - M.getFirstms(track));
sidxBox.setEarliestPresentationTime(keys.getTime(0) + parts.getOffset(0) -
M.getFirstms(track));

for (size_t i = 0; i < fragments.getEndValid(); i++){
size_t firstKey = fragments.getFirstKey(i);
size_t endKey =
((i + 1 < fragments.getEndValid()) ? fragments.getFirstKey(i + 1) : keys.getEndValid());

MP4::sidxReference refItem;
refItem.referencedSize = payloadSize(M, track, keys.getTime(firstKey), keys.getTime(endKey)) + keyHeaderSize(M, track, i) + 8;
refItem.referencedSize =
payloadSize(M, track, keys.getTime(firstKey), keys.getTime(endKey)) +
keyHeaderSize(M, track, i) + 8;
refItem.subSegmentDuration =
(endKey == keys.getEndValid() ? M.getLastms(track) : keys.getTime(endKey)) - keys.getTime(firstKey);
(endKey == keys.getEndValid() ? M.getLastms(track) : keys.getTime(endKey)) -
keys.getTime(firstKey);
refItem.sapStart = true;
refItem.sapType = 16;
refItem.sapDeltaTime = 0;
Expand Down Expand Up @@ -209,7 +199,8 @@ namespace CMAF{
}

/// Generates the 'moof' box for a DTSC::Key based CMAF fragment.
std::string keyHeader(const DTSC::Meta &M, size_t track, uint64_t startTime, uint64_t endTime, uint64_t segmentNum, bool simplifyTrackIds, bool UTCTime){
std::string keyHeader(const DTSC::Meta &M, size_t track, uint64_t startTime, uint64_t endTime,
uint64_t segmentNum, bool simplifyTrackIds, bool UTCTime){

size_t firstPart = M.getPartIndex(startTime, track);
size_t endPart = M.getPartIndex(endTime, track);
Expand All @@ -218,10 +209,9 @@ namespace CMAF{
MP4::MFHD mfhdBox(segmentNum);
moofBox.setContent(mfhdBox, 0);


std::set<sortPart> trunOrder;

//We use keyHeaderSize here to determine the relative offsets of the data in the 'mdat' box.
// We use keyHeaderSize here to determine the relative offsets of the data in the 'mdat' box.
uint64_t relativeOffset = keyHeaderSize(M, track, startTime, endTime) + 8;

sortPart temp;
Expand All @@ -242,21 +232,20 @@ namespace CMAF{

tfhdBox.setFlags(MP4::tfhdSampleFlag | MP4::tfhdBaseIsMoof | MP4::tfhdSampleDesc);
tfhdBox.setTrackID(track + 1);
if (simplifyTrackIds){
tfhdBox.setTrackID(simplifiedTrackId(M, track));
}
tfhdBox.setDefaultSampleDuration(444);
tfhdBox.setDefaultSampleSize(444);
tfhdBox.setDefaultSampleFlags((M.getType(track) == "video") ? (MP4::noIPicture | MP4::noKeySample)
: (MP4::isIPicture | MP4::isKeySample));
tfhdBox.setDefaultSampleFlags((M.getType(track) == "video")
? (MP4::noIPicture | MP4::noKeySample)
: (MP4::isIPicture | MP4::isKeySample));
tfhdBox.setSampleDescriptionIndex(1);
trafBox.setContent(tfhdBox, 0);

MP4::TFDT tfdtBox;
if (M.getVod()){
tfdtBox.setBaseMediaDecodeTime(startTime - M.getFirstms(track));
}else{
tfdtBox.setBaseMediaDecodeTime((UTCTime ? startTime + M.getBootMsOffset() + unixBootDiff : startTime));
tfdtBox.setBaseMediaDecodeTime(
(UTCTime ? startTime + M.getBootMsOffset() + unixBootDiff : startTime));
}
trafBox.setContent(tfdtBox, 1);

Expand All @@ -277,15 +266,14 @@ namespace CMAF{
MP4::trunSampleInformation sampleInfo;
sampleInfo.sampleSize = parts.getSize(it->partIndex);
sampleInfo.sampleDuration = parts.getDuration(it->partIndex);
if (it == lastOne){
sampleInfo.sampleDuration = endTime - it->time;
}
if (it == lastOne){sampleInfo.sampleDuration = endTime - it->time;}
sampleInfo.sampleOffset = parts.getOffset(it->partIndex);
trunBox.setSampleInformation(sampleInfo, trunOffset++);
}
}else{
WARN_MSG("Empty CMAF header for track %zu: %" PRIu64 "-%" PRIu64 " contains no packets (first: %" PRIu64
", last: %" PRIu64 "), firstPart=%zu, lastPart=%zu",
WARN_MSG("Empty CMAF header for track %zu: %" PRIu64 "-%" PRIu64
" contains no packets (first: %" PRIu64 ", last: %" PRIu64
"), firstPart=%zu, lastPart=%zu",
track, startTime, endTime, M.getFirstms(track), M.getLastms(track), firstPart,
endPart);
}
Expand Down
38 changes: 22 additions & 16 deletions src/output/output_cmaf.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -489,32 +489,32 @@ namespace Mist{
}

void OutCMAF::generateSegmentlist(size_t idx, std::stringstream &s,
void callBack(uint64_t, uint64_t, std::stringstream &, bool)){
DTSC::Fragments fragments(M.fragments(idx));
void dashSegmentCallBack(uint64_t, uint64_t,
std::stringstream &, bool)){
// NOTE: Weirdly making the 0th track as the reference track fixed everything.
// Looks like a nomenclature issue.
// TODO: Investigate with spec and refactor stuff appropriately.

size_t mainTrack = *M.getValidTracks().begin(); // M.mainTrack();

if (mainTrack == INVALID_TRACK_ID){return;}
DTSC::Fragments fragments(M.fragments(mainTrack));
uint32_t firstFragment = fragments.getFirstValid();
uint32_t lastFragment = fragments.getEndValid();
bool first = true;
// skip the first two fragments if live
if (M.getLive() && (lastFragment - firstFragment) > 6){firstFragment += 2;}

if (M.getType(idx) == "audio"){
uint32_t mainTrack = M.mainTrack();
if (mainTrack == INVALID_TRACK_ID){return;}
DTSC::Fragments f(M.fragments(mainTrack));
uint64_t firstVidTime = M.getTimeForFragmentIndex(mainTrack, f.getFirstValid());
firstFragment = M.getFragmentIndexForTime(idx, firstVidTime);
}

DTSC::Keys keys(M.keys(idx));
DTSC::Keys keys(M.keys(mainTrack));
for (; firstFragment < lastFragment; ++firstFragment){
uint32_t duration = fragments.getDuration(firstFragment);
uint64_t starttime = keys.getTime(fragments.getFirstKey(firstFragment));
if (!duration){
if (M.getLive()){continue;}// skip last fragment when live
duration = M.getLastms(idx) - starttime;
duration = M.getLastms(mainTrack) - starttime;
}
if (M.getVod()){starttime -= M.getFirstms(idx);}
callBack(starttime, duration, s, first);
if (M.getVod()){starttime -= M.getFirstms(mainTrack);}
dashSegmentCallBack(starttime, duration, s, first);
first = false;
}

Expand Down Expand Up @@ -662,7 +662,7 @@ namespace Mist{
it++){
if (M.getType(it->first) == "video"){vTracks.insert(it->first);}
if (M.getType(it->first) == "audio"){aTracks.insert(it->first);}
if (M.getType(it->first) == "subtitle"){sTracks.insert(it->first);}
if (M.getCodec(it->first) == "subtitle"){sTracks.insert(it->first);}
}

if (!vTracks.size() && !aTracks.size()){return "";}
Expand All @@ -685,12 +685,18 @@ namespace Mist{
<< "\" suggestedPresentationDelay=\"PT5.0S\" minBufferTime=\"PT2.0S\" publishTime=\""
<< Util::getUTCString(Util::epoch()) << "\" ";
}

r << "xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" ";
r << "xmlns:xlink=\"http://www.w3.org/1999/xlink\" ";
r << "xsi:schemaLocation=\"urn:mpeg:DASH:schema:MPD:2011 "
"http://standards.iso.org/ittf/PubliclyAvailableStandards/MPEG-DASH_schema_files/"
"DASH-MPD.xsd\" ";
r << "profiles=\"urn:mpeg:dash:profile:isoff-live:2011\" "
"xmlns=\"urn:mpeg:dash:schema:mpd:2011\" >"
<< std::endl;
r << "<ProgramInformation><Title>" << streamName << "</Title></ProgramInformation>"
<< std::endl;
r << "<Period " << (M.getLive() ? "start=\"0\"" : "") << ">" << std::endl;
r << "<Period " << (M.getLive() ? "start=\"PT0.0S\"" : "") << ">" << std::endl;

dashAdaptation(1, vTracks, videoAligned, r);
dashAdaptation(2, aTracks, audioAligned, r);
Expand Down

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