This requires to prepare the media source and the periods in a small helper similar
to the metadata retriever. It also gets rid of the need to have abstract protected
methods to load the manifest, to extract the track groups and to convert to stream keys,
as this can now be handled by the media period.
PiperOrigin-RevId: 231385590
That's the same position set in MediaPeriod.prepare (where it may be removed
in the future).
Having the position at an earlier point is necessary to fix an
issue with lazy preparation in ConcatenatingMediaSource where the prepare
position was assumed to be known but MediaPeriod.prepare hasn't been called
yet.
Issue:#5350
PiperOrigin-RevId: 229756637
When the extra adaptation set of a switch group isn't defined in the manifest, we
currently assume it's the first adaptation group. This either leads to wrong grouping
or duplicate track groups.
Such a case may easily happen if the manifest is filtered such that only one of the
switch adaptation sets will be present in the manifest.
PiperOrigin-RevId: 229365379
They are not longer needed anywhere, are error-prone (because of threading
requirements), and complicate testing and using MediaSources without a player.
PiperOrigin-RevId: 227871157
- Enable GZIP for media playlist + encryption key chunk requests in
HLS, as we do during playback
- Pass around DataSpecs rather than Uris. This will be needed for if
we add manifest cacheKey support (which seems like a good idea for
completeness, if nothing else)
PiperOrigin-RevId: 224057139
Moving most of the logic to the base DownloaderHelper helps to implement track
selection for downloading in a single place instead of multiple places.
PiperOrigin-RevId: 223964869
A remove action will eventually just be the unique ID of the download
that should be removed. This is a step toward that goal.
PiperOrigin-RevId: 222832456
1. Pull up all subclasses of DownloadAction into DownloadAction
2. Add DownloaderFactory for Downloader instantiation, and DefaultDownloaderFactory
to replace the instantiation logic being removed from the DownloadAction
subclasses.
This change will upgrade existing action files gracefully (i.e. it does not
lose compatibility with the existing offline implementation, other than some
minor breaking changes to the API).
TODOs:
1. Move test methods from the XDownloadActionTest classes into DownloadActionTest.
This will be done in a subsequent CL. There's a lot of consolidation that can
be done here, including de-duplicating some of the test code added in this CL.
2. Look at merging DownloaderConstructorHelper into DefaultDownloaderFactory.
3. Use customCacheKey in DASH/HLS/SS Downloaders, for completeness.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=222258983
The remaining work is to split Window.isDynamic so that it's
possible to represent a window that wont be appended to, but
may still be removed from.
Issue: #4780
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=221439220
Robustness fix to make sure we ignore tags with known names, but
which are nested inside of unknown tags. For example we don't want
to parse the third period in:
<Period>...</Period>
<Period>...</Period>
<CustomTag>
<Period>...</Period>
</CustomTag>
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=217101630
- Always clip to period duration for the last chunk. We previously
did this only when the last chunk explicitly exceeded the period
end time. We now also do it when the chunk claims to end at the
period boundary, but still contains samples that exceed it.
- If pendingResetPositionUs == chunk.startTimeUs == 0 but the
chunk still contains samples with negative timestamps, we now
clip them by setting the decode only flag. Previously we only
clipped such samples if the first chunk explicitly preceeded the
start of the period.
Issue: #4899
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=215763467
Currently there is no way to disable (or reduce) the logcat output generated
by ExoPlayer.
Issue:#4665
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=213421072
The default character set is always UTF-8 anyway on Android, but
we don't want our code to behave any differently where it's not
(e.g. robolectric test runs could potentially run in an environment
where UTF-8 isn't the default?).
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=211953885
This provides the list of currently buffered media chunks and iterators over
the potential next chunks to the track selection. Having these two parameters
enables more advanced decision logic based on this data.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=210551812
The response headers of the last load are available from the loading source
when creating media source events and can be easily forwarded.
Issue:#4361
Issue:#4615
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=209900693
The MediaPeriodId with index is only properly defined together with a
timeline containing the index. Changing it to the period uid allows to use
the MediaPeriodId independent of the corresponding timeline.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=209430257
Also fix an NPE in FfmpegAudioRenderer if sampleMimeType wasn't set.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=208230947
For now, just allow any prefix (and don't check the namespace).
Checking the namespace requires turning on the XmlPullParser
namespace awareness feature, but this can only be done before
parsing, and I think requires us to specify the namespace when
querying other attributes. This would also risk breaking services
who currently don't set namespaces correctly.
It's possible we'll run into similar issues with the few other
tags (e.g. mspr:pro). We should revisit enabling namespace
awareness if/when we see this.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=207526883
EventSampleStream.readData required eventStreamUpdatable to be
false for END_OF_STREAM to be returned, but it was only being
set to false when the manifest became static. This change also
sets it to false if the period is not the last one in a dynamic
manifest. It also renames it the parameter to appendable, since
that's what it really represents. Events may still be removed
from the start of the EventStream as the period starts moving
out of the live window.
Issue: #4492
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=207517265
All known instances use DataSource as generic type and thus code can be simplified
by removing the generic type altogether.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=205798542
As the manifest and media data sources can be the same now, we can provide
a simplified constructor with just one data source factory.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=205658046
This removes the need to populate the entire period for the common usage of
getting the uid from the period.
Also add default implementation to get period by uid.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=205638265
Until now, the streams were released and re-enabled for each type of stream
(primary, event, embedded) in that order. That leads to problems when replacing
streams from one type to another (for example embedded to primary).
This change restructures the track selection to:
1. Release and reset all streams that need to be released or replaced.
1(a). Including embedded orphan streams.
2. Select new streams.
Issue:#4477
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=203751233
This wires up recent changes of passing a transfer listener to the MediaSource and
allowing DataSources to accept new listeners.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=203280818
This allows to use this queue in the track selection in the future.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=202954871
This will allow to provide available information about future chunks to the
track selection.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=202940994
In the future, this allows to register the BandwidthMeter (managed by the player)
as a listener to all media transfers related to this media source.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=202643946
This url is readily available when creating media source events (from the
data source) but so far not published to external listeners. This change
adds a new field to LoadEventInfo which corresponds to DataSource.getUri().
Issue:#2054
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=202459049
Also moved shared code to SegmentDownloadAction between its subclasses.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=202294880
Both values are helpful for event reporting, but are only available while
the data source is open. Similar to bytesLoaded, they need to be reported
through the Chunk.
Issue:#2054
Issue:#4361
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=201664907
The helper method only reported DATA_TYPE_UNKNOWN even if the actual type
is known.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=200067296
Using new Handler(this) in a constructor potentially leaks an uninitialized
object. This is mostly not a problem because we don't use the Handler within
the constructor. Added a Util method to keep the warning suppression local.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=199605377
If a MediaPeriod uses a Loadable, then there are typically
reference chains of the form:
LoadingThread[GCroot]->Loadable->MediaPeriod->Player
Where the player is the MediaPeriod callback. When the
player is released, this reference chain prevents the
player from being GC'd until Loadable cancellation
completes, which may not always be fast. This in turn
will typically prevent the application's activity from
being GC'd, since it'll normally be registered as a
listener on the player (directly or indirectly via
something like a view).
This change mitigates the issue by removing references
that the MediaPeriod holds back to the player. The
MediaPeriod will still not be eligible for GC, but the
player and application activity will be, which in most
cases will be most of the leak (in terms of size).
Issue: #4249
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=199143646
The lint error suppression only works locally and not for external developers
who still see the lint error and need to suppress it themselves.
This changes 'implementation' to 'compileOnly' in gradle to prevent the
dependency from being exported. Also removes the local lint suppression.
Issue:#4234
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=196251407
This is useful to get hold of the manifest to then obtain DRM init data in
the download flow for protected content (without having to download the
manifest again).
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=196168938
This type of flicker was visible (at least on my S8) whenever starting
the demo app process (from being properly killed) when other notifications
(e.g. completed download notification) was present.
This change passes whether the service was started as foreground through
the intent, and only applies the show-notification-on-stop hack if it
was. It's only necessary to start as foreground if your app is not already
in the foreground, so it's not necessary to do this from activity/ui
components.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195594930
Also convert them to exposing periods and track groups, like
regular MediaSources do. This gets us much closer to being
able to use standard track selection components during offline
initialization. The helper is responsible for reverse mapping
selected tracks onto physical streams when generating the
download action. This is trivial except for the HLS case, which
is a TODO for now.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195500826
This may be preferable for using custom binary data,
and it's still easy to store Strings if needed.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195486817
- Made parts of DownloadActions public that were previously hidden.
This is necessary so that when an app is listening to the
DownloadManager, it can tell something about the tasks.
- Simplified DownloadActivity some more. The helpers may migrate
into their corresponding modules at some point, and also be
converted to return structured TrackGroupArrays rather than a
flat list of Formats.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195269824
Also add a build rule to simplify the test setup with a custom blacklist.
In addition, the test path pattern are made less specific to capture all the
static nullness tests in the /main/ directories.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195230334
This includes only the (hopefully) non-debatable changes for the DASH module
and all needed changes for call into the core library.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195097791
A single master version prevents app developers from providing
custom download functionality (because they can't increment the
version). It's also error prone to expect someone modifying the
DASH action to remember to update the ActionFile master version.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194981886
This was adding a lot of code, and the multiple use cases
for Downloader was pretty confusing (in particular the
ordering of method calls was unclear). It's also not
performant (e.g. it requires loading/parsing manifest(s)
and initialization segments from disk).
In practice I think apps will need to keep a record of
what's offlined in their app's database (or equivalent),
which they can update by registering as a listener on
DownloadManager. This will be done for the demo app in
a subsequent change.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194932876
- It's much cleaner to split completed/error notification methods.
- Make error notification show the content title in the demo app.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194920507
This change is intended to resolve overloading of "Download",
where a DownloadTask could be an actual download task, or a
remove task.
Also cleaned up some documentation.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194815058
- Redefine Scheduler interface to better describe what implementations
do. The previous version was too general, in that it allowed concrete
DownloadService implementations to pass different Requirements to
the base class and to the Scheduler. It's also difficult to see how
that version could ever support dynamic updates to Requirements, which
is probably a feature we'll need to add quite soon.
- Fix a (probably theoretical) problem where static fields in
DownloadService assumed only a single concrete implementation.
- Stop using PlatformScheduler pre-API-21 in demo app, because it will
fail.
- Define default Requirements that require network.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194785751
- When calculating the downloaded percentage in DASH, there was no
way to disambiguate between 0 of 0 segments being downloaded because
there are no cached indexes (i.e. 0% downloaded) and 0 of 0 segments
being downloaded because the index defines 0 segments (i.e. 100%
downloaded).
- Also replace use of NaN with a named constant.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194453202
When we play downloaded content, we rely on the manifest filters
to produce a manifest that contains only the content that was
downloaded. It makes sense just to use the same filters during
download too, so we don't have to worry about any implementation
differences.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194380704
ProgressiveDownloader never implemented this properly, and we
don't use it in DownloadManager/DownloadService, both of which
use a polling model. A polling model is also what's used elsewhere,
for example to query the current playback position.
This is effectively doing the TODO in ProgressiveDownloader.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194214579
This removes a fair chunk of code. The line delta would
be more negative if it not for adding all the /* x= */
comments in DashDownloadActionTest!
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194136689
This makes DownloadService easier to use in general and when only single
notification is used for all downloads.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=193165982
These don't seem to be needed anymore. All tests run without them in gradle
and Blaze.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=191867518
This field (formerly "id") is almost impossible to use so far. Having setters
in the factories allows to specify custom tags for all media sources.
Also added a ExoPlayer.getCurrentTag() method to retrieve the tag of the
currently playing media source in a convenient way.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=191738754
We currently refresh repeatedly in this case. According to the
DASH spec omitting minUpdatePeriod indicates that the manifest
does not change, and therefore we should not refresh. I think
it might be valid to omit minUpdatePeriod in a dynamic manifest
if relying exclusively on EMSGs to trigger manifest refresh.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=191420247
This change enables feeding decoders from the closest sync frame
before a specified seek position, where-as previously we'd
always feed decoders from the start of the chunk. This avoids
decoding and discarding many audio samples during each seek. The
same benefit also applies to video chunks containing more than
one key-frame.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=190539547
This adds callbacks for creating, releasing, and starting to read from media
periods.
Such events allow listeners to keep a list of active media periods. This is
useful to determine when no further events for a certain media period are
expected. It also allows listeners to associate renderer events unambigiously
with a reading media period.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=190462717
Also convert left side from milliseconds to microseconds for comparison
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=189784833
This allows to distinguish between media source events of multi-window and
multi-period media sources. In this change, only media sources currently reporting
events are changed. Proper support in composite sources will be added in a later
change.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=188847366
This is achieved by moving the listener registration and the creation of the
event dispatcher into BaseMediaSource.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=188461932
- Change 'compile' configuration (deprecared) to using 'implementation'
and 'api' configurations instead.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=187311778
This is achieved by adding a BaseMediaSource which keeps a reference count of the
number of times the source has been prepared and forwards to the actual implementations
only once, such that only minimal changes are needed for each media source.
Issue:#3498
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=187186691
The util package is, in practice, for things that are misc enough
to not warrant their own package. If something is deserving of a
package, it's IMO best placed somewhere else (I know you could
argue it's a util, but you could argue that about almost anything
else as well).
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=187010018
Releasing the player released the internal playback thread once renderers were
released. Releasing a MediaPeriod queued a Loader.ReleaseTask on the loading
thread which would post back to the playback thread. If the playback thread had
been quit by the time this happened, the release task wouldn't be run.
Release on the loading thread instead of the playback thread. This avoids
needing to block releasing the player until the loading threads have ended, and
ensures that release tasks will run eventually. As part of this change,
ExtractorMediaPeriod's call to Extractor.release will now run on the loading
thread (which means that all Extractor methods are called on that thread) and
other cleanup in ReleaseCallback will run on the loading thread instead of the
playback thread.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185651320
Lint recommends switching to SparseArray<X> instead.
This is done for the DASH case. For the Cast case it's
easier to use a switch statement.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184119312
This is only allowed for user-replaced manifest uris. If the manifest
itself forwards to another manifest, we keep the original manifest in
case the forwarding changes.
Also removed the initialManifest as it can be simplified by using the
sideloadedManifest indicator.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=183376209
These parsers can be used to get a manifest which includes only the
representations identified by the given keys.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=182932874
This achieves two things:
1. All our tests use the same type of assertions.
2. The tests currently run as instrumentation test can be moved to
Robolectric without changing the assertions.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=182910542
When a loaded DASH manifest is invalid (either some periods were removed
illegally, or a manifest for a live event is stale), we will retry using 1
logic:
- Retry loading with back-off up-to a limit.
- Throw a DashManifestExpiredException() if we exceed retry limit.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=182770028
This fixes a very specific case where the data read has non-cached gaps
and a read-only CDS switches to read from upstream in a gap then the
cached data is deleted. When the CDS reaches the end of the gap, it
tries to open the next source. As there is no cached data, it tries to
continue with the already opened upstream data source but as it reached
end of the gap range, the code starts looping.
Also fixes infinite lock which occurs when in the previous case CDS isn't
readonly. It locks the content while filling the gap in the cache. At the
end of the gap, as the following data is deleted it tries to lock the
content for writing but the content is already locked by itself.
The last fix is preventing removal of CachedContent entry from
CachedContentIndex while associated key is locked.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=182595426
- Get handling of "stale" and "out of sync" manifests so
they're right next to each other (to be merged)
- Move startLoadingManifest to be next to the methods that
schedule it, and actually start loading stuff.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=182530683
For live streaming, there are several types of DASH `emsg' events that directly
target the player. These events can signal whether the manifest is expired, or
the live streaming has ended, and should be handle directly within the player.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=182034591
This allows listeners to get notified of any change to the embedded tracks.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=181969023
This lets apps fail-fast when they try to reuse media source instances.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=180934445
DASH manifests can now contain non-null but incomplete
DRM init data. Hence using the manifest init data when
non-null is not always the correct thing to do. This
change merges the sample and manifest formats (which
correctly merges the DRM init data) and then uses the
result.
Issue: #3630
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=180787784
- Parse multiple kids from default_KID. It's specified as a whitespace
separated list of UUIDs rather than a single UUID.
- Opportunistically proceed with playback in cases where the manifest
only defines a single SchemeData with the common PSSH UUID. In such
cases the manifest isn't saying anything about which specific DRM
schemes it supports.
Issue: #3630
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=180675056
This is in preparation for supporting non-extractor MediaSources for ads in
AdsMediaSource.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=178377627
In some occasions, we may want to discard a part of the buffered media to
improve playback quality. This CL adds this functionality by allowing the
loading media period to re-evaluate its buffer periodically (every 2s) and discard
chunks as it needs.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=177958910
Parse DASH manifest's publishTime node as defined by ISO/IEC 23009-1:2014,
section 5.3.1.2.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176525922
Currently EventMessage's presentationTimeMs is kept separately in
EventSampleStream. However, EventMessage's presentationTimeMs maybe used in
other places besides EventSampleStream, such as when handling `emsg' messages
targeting the player. This CL let EventMessage object to holds its
presentationTimeMs for such use cases.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176502938
Currently for a DASH ChunkSource that consists of multiple sub-streams, we
always use a CompositeSequenceableLoader, which only allows the furthest behind
loader or any loader that are behind current playback position to continue
loading.
This changes allow clients to have more flexibility when deciding the loading
strategy:
- They can construct a different kind of composite SequenceableLoader from
the sub-loaders, and use it by injecting a different CompositeSequeableLoaderFactory accordingly.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176363870
Add Builder pattern to SsMediaSource and mark existing constructors as
deprecated.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=175659618
This is a step toward retaining a back-buffer in a way that
works for all MediaSource implementations. It's not possible
to adjust the discardBuffer calls in ExoPlayerImplInternal
to discard up to (position - backBufferDurationUs). Next steps
are to:
1. Find an appropriate place to specify the back buffer value,
to be passed to the discardBuffer calls. I guess the
LoadControl is the appropriate place to define such values.
2. Enhance discardBuffer to support a toKeyframe argument to
pass through to discardTo.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=175565363
Start with DASH MediaSource. The number of injected arguments is getting
out-of-control.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=175529031
MPD file may include multiple EventStreams in its Periods, which contains Events
that the application may need to handle/respond to.
This change adds support for parsing the EventStream/Event nodes from MPD
file, and exposing these EventStreams as a metadata sample stream that application
can respond in a similar way to other metadata events.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=175017697
... by making it case insensitive and null-tolerant for schemeId (as was before
adding playlist drm data merging).
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=174472123
This also allows exposing multiple CC channels to any fMP4 extractor client.
Issue:#1661
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=174458725
