## The issue
- With LL-DASH mode enabled, the gap size warning was hit and printed to the console every time a new segment was registered to the manifest.
- This occurred because the first chunk's size and duration were being stored for each segment, rather than the full segment size and duration. Note, only the first chunk's metrics are known at first because in low latency mode, the segment is registered to the manifest before it is finished being processed and written.
- Because of this, the gap size check was comparing the end time of the first chunk in the previous segment to the beginning time of the current segment, causing the check to fail every time.
## The Fix
- Update a low latency segment's duration and size once the segment file has been fully written.
- The full segment size and duration will be used to update the bandwidth estimator and the segment info list.
- Updating the segment info list to hold the full duration is necessary for satisfying [the gap size check found in Represenation.cc](https://github.com/google/shaka-packager/blob/master/packager/mpd/base/representation.cc#L391).
- NOTE: bandwidth estimation is currently only used in HLS
# LL-DASH Support
These changes add support for LL-DASH streaming.
**NOTE:** LL-HLS support is still in progress, but it's coming. :)
## Testing
`./chunking_unittest --gtest_filter="ChunkingHandlerTest.LowLatencyDash"`
`./media_event_unittest --gtest_filter="MpdNotifyMuxerListenerTest.LowLatencyDash"`
`./mpd_unittest --gtest_filter="PeriodTest.LowLatencyDashMpdGetXml"`
`./mpd_unittest --gtest_filter="SimpleMpdNotifierTest.NotifyAvailabilityTimeOffset"`
`./mpd_unittest --gtest_filter="SimpleMpdNotifierTest.NotifySegmentDuration"`
`./mpd_unittest --gtest_filter="LowLatencySegmentTest.LowLatencySegmentTemplate"`
Note, packager_test must be run from the main project directory
`./out/Release/packager_test --gtest_filter="PackagerTest.LowLatencyDashEnabledAndUtcTimingNotSet"`
`./out/Release/packager_test --gtest_filter="PackagerTest.LowLatencyDashEnabledAndUtcTimingNotSet"`
This converts all time parameters to signed, finishing a cleanup that
was started in 2018 in b4256bf0. This changes the type of:
- timestamps
- PTS specifically
- timestamp offsets
- timescales
- durations
This excludes:
- MP4 box definitions
- DTS specifically
This is meant to address signed/unsigned conversion issues on arm64
that caused some test cases to fail.
Change-Id: Ic752a20cbc6e31fea6bc0894d1771833171e7cbe
This is needed to support one file per representation per period where
there will be multiple content files generated.
Issue: #384
Change-Id: Ib7af750edf864d99075b8da4f3640217a5a94302
It is now managed in SimpleMpdNotifier.
This avoids unnecessary increment in AdaptationSet id counter.
Also makes sure the AdaptationSet is sorted by id in XML output.
Change-Id: Ibcd0b047a71c19cd30ad7d8af9a2ed0bb05e043e
Prefer timestamps from Video AdaptationSets if available - this avoids
possible video playback jitters due to gaps.
presentationTimeOffset is not applied to the first period as it may in
negative dts which Chrome does not like: https://crbug.com/398141.
It is safe to apply to subsequent periods as the actual offset applied
takes Period@start into consideration:
offset = Period@start - presentationTimeOffset
The result timestamp with offset applied is close to Period@start, so
it is unlikely to result in a negative dts value.
Closes b/73899306.
Change-Id: If8361f5469610093b3aac6675754536ad7e83c4c
There could be rounding errors in MSE which could cut the first key
frame of the representation and thus cut all the frames until the next
key frame, which then leads to a big gap in presentation
timeline which stalls playback.
Adjusting presentationTimeOffset (PTO) by -1, i.e. backing off PTO by 1
to compensate for the possible rounding error. It should not cause any
playback issues as it is small enough. The workaround can be removed
once the problem is handled in all players.
The PTO adjustment is configurable with command line flag:
--pto_adjustment, with value set to -1 by default.
b/71808910
Change-Id: I9c4d1e2ee84008b859a3638a8146c910cead1f15
Move AdaptationSet related functions to the new Period class, which
maps to <Period> element and provides methods to add AdaptationSets.
Change-Id: I0fee290769fbe9a6355cc1b8c86baec8fbc4b4fd
- Added two new fields in MpdOptions: dash_profile and mpd_type
- Updated MpdBuilder to support LiveProfile with static mpd
- Command line arguments will be updated in the next CL
Issue #142
Change-Id: Ibd35e5c9e1b1ef98043392e3f04a0af4700135c1
1. Replace STLDeleter with unique_ptr in container, which is
supported in C++11
2. Replace string_as_array with &string[0] which is guaranteed
to work in C++11
Change-Id: I7f39c0e51fc8a3fcbb41313094a0ca6b33db7bf3
This adds a new function to key AdaptationSets based on the
characteristics that require separate sets.
With this, we are now able to package multi-codec assets at once
(AVC1/MP4 and VP9/WebM in the same manifest, but in different
AdaptationSets).
Fixes b/27534371
Change-Id: Ie82fd096d2ef99fd23e323d60fd0849b1e8d7500
- Since most use cases use notifier implementations that already uses
locks, removing locks from MpdBuilder.
- Added locks to MpdNotifier::Flush() implementations. Multiple threads
were able to write to the same file.
Issue #45, #49
Change-Id: I6e39824485672f40e6c947da97f1743fac174167
- Neither live with or without key rotation did not output the right
result.
- No key rotation: did not produce any ContentProtection element.
- With key rotation: did not have DRM specific ContentProtection.
- To get key rotation working with shaka player, <cenc:pssh> elements
are removed.
Change-Id: I1f34d303ae1f3ea81820e3368ab66b8420498372
- Because MpdBuilder no longer sets ContentProtection, live was broken.
- For key-rotation, <cenc:pssh> element is updated.
Change-Id: I45bb80a12faff39ccf5deb82439c0732ed9cea59
- Without the Flush() method the implementation had to do writes in
almost all methods. Usually the user of the notifier knows when to
write out the MPD.
Change-Id: Ic165d4594f01357a8ac7e8501eefa0f85c08d32f
- SimpleMpdNotifier didn't register the container ID to its map for VOD.
- AddContentProtection() was not implemented.
Change-Id: I5f1412c785ee5ad3d00910755ff283c404dd895c
- ContentProtection elements should be added explicitly by the
AddContentProtection() methods.
- This is because some MPDs should have ContentProtection at
AdaptationSet level instead of Representation.
- Change SimpleMpdNotifier, which uses MpdBuilder, to add
ContentProtectionElements. The logic is moved from MuxerListener.
- Add Element class for specifying subelements for
ContentProtectionElement.
Change-Id: I9bedfb3e5a5ac0b3d5c702f1e6e4a8608c978d1d
- The fields used to be repeated but there is no use case at the moment.
- DASH IOP explicitly disallows segments with multiple tracks.
Change-Id: Ia0af2048210c546dfaa178735605a81052ea1123
- Get the first sample duration in Segmenter.
- Pass the value all the way to Representation thru MuxerListener.
Change-Id: I76fd970f8140d359863363dc347958f680cca5ae
Additionally, for XML schema correctness, convert ISO-639-2 language
tags (three-letter codes) to ISO-639-1 tags (two-letter codes) when
possible. This follows BCP-47, which says to always use the shortest
language tag when there are multiple possibilities.
b/18613148
Change-Id: I120fb7b42ac4da5feb4ca046bba93d9e58acd7a9
This is a follow up to previous CL.
Generated using command:
find {media,app,mpd} -type f -exec sed -r -i 's/#include "(.*)"/#include
"packager\/\1"/' {} \;
common.gypi and mpd.gyp are also modified to take the path change into
consideration.
Change-Id: I1fb102b4eb73ae5fde5f4ab303a12cec09b05c33
Caitlin O'Callaghan
Joey Parrish
KongQun Yang
Rintaro Kuroiwa
Thomas Inskip