Moved the behaviors related to Cue's to the WebvttCueParser class.
This way, the parsing methods will be more easily accessible to
other classes, such as the MP4Webvtt parser. This class also has
some methods that require state to avoid repetitive avoidable
allocations. The method visibility is subject to changes in
further CLs.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=111616824
This CL is prepares the ground for refactoring the Webvtt parser,
so as to use the common parsing algorithms in both parsers. In order
to do this, the Webvtt Parser will be refactored. As a side note, many
more test cases will be added once the new subtitle features are
implemented. Some useful test cases have also been left for a following
CL, to allow an easy code review.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=110466914
Multiple identical TTML fontStyles or fontWeights or textDecorations
on the content for a specific moment were rendered as if there's only
one decoration (span).
That's because SpannableStringBuilder.setSpan(span, start, end, flag)
found an earlier set span (the static allocated span's reference
is the same each time) and only refreshed this first span's start and
end values instead of adding a new span at its (new) different range.
This patch removes the static data members;
this makes the newly allocated span objects distinguishable.
A correct implementation is favoured over worries about memory
consumption.
This is the main component required to enable WebVTT subtitles in HLS.
It passes through each WebVTT file as a sample, and derives the correct,
adjusted timestamp for each of them on the way through.
Not yet wired up because we need to properly share the same
PtsTimestampAdjuster everywhere, and also stop instantiating new instances
of the adjuster. The adjuster will also need to correctly handle
discontinuities, since we'll no longer be creating new instances of it.
Issue: #151
- parse webvtt cue
- remove all tags from string (supported or not)
- apply spans for b, i and u
- honor class names in tags to properly parse the cue but do not apply styles for them
* Split findNextCueHeader and validateWebVttHeader into static methods.
This is a step toward WebVTT in HLS, where we'll need to re-use these
to peek at the top of the WebVTT file (they'll be moved into a util
class).
* Made parser robust against bad cue headers + added a test.
* Removed spurious looking assertion in WebvttSubtitle.
They don't seem particularly useful; they don't technically force
strict compliance, but rather just catch a few token things in
each case. Furthermore, for playback, probably the right thing to
do is to always turn strict mode off.
- Line parameter
- Added support for value and line alignment attributes.
- Support negative numbers when line is an absolute number (not a
percentage).
- Position parameter
- Added support for value and position alignment attributes
- Added support for WebVTT comment blocks
- Percentage values now accept decimal numbers (as webvtt spec states)
- Added new WebVTT tests for testing all new implemented features
- do not denormalize styles at parsing time but only put normalized style info
into TtmlNode tree. Resolve styles on demand when Cues are requested for a
given timeUs.
- create TtmlRenderUtil to have static render functions separate
- added unit test for TtmlRenderUtil
- adjusted testing strategy for unit test to check resolved style on Spannables after rendering
- Don't allow "nothing has changed" optimization in the case
that only styling has changed (TextUtils.equals will return
true in this case, but we shouldn't optimize).
- Add functionality to suppress embedded styling; seems useful
to have.
- Added "this." for clarity.
- Remove unused method in DashChunkSource.
- Remove inputEncoding parameter for subtitle parsers. We're
ignoring it in all but one of the parsers, and for the one
that does use it, it'll only ever receive null, since that's
all we're passing.
- Make TextTrackRenderer advance to the next subtitle even if
the current one hasn't finished, in the case that they overlap.
This shouldn't ever really happen, but it seems best to trust
the start time of the new sample rather than the last event
time of the previous one.
- Currently all subtitles we parse contain timestamps relative to the sample
timestamp, however we add the sample timestamp in inconsistent ways (sometimes
in the Subtitle, sometimes in the SubtitleParser). This change converges on
a single approach. It also paves the way for passing absolute offsets to use
instead, and being able to apply them in a consistent way in a single place
(PlayableSubtitle). This functionality will be required for ISO 14496-30 TTML
embedded subtitles.
Issue: #689
- Generalize rendererEnabledFlags to be selected track indices through
ExoPlayerImpl/ExoPlayerImplInternal.
- Selecting an out-of-bound track index (e.g. -1) is equivalent to
disabling a renderer prior to the generalization.
- A prepared TrackRenderer that exposes 0 tracks is equivalent to a
TrackRenderer in the STATE_IGNORE state prior to the generalization.
Issue #514.
1. [Cleanup] Remove unused Track types, including TYPE_TIME_CODE.
2. Add subtitle track type, which is different to the existing text type.
3. Set duration on the media formats for text and subtitle tracks. This
was causing the player to report unknown media duration for mp4 files
containing such tracks.
4. Make TextTrackRenderer do the right thing when not started.
Issue: #635
SubtitleLayout no longer trigger re-layouts of the view hierarchy.
Instead, the SubtitleLayout just invalidates itself. This is made
possible by making SubtitleLayout a regular View that draws each Cue
directly onto the canvas, rather than having SubtitleLayout be a
ViewGroup with a child View for each Cue.
The SubtitleLayout is now properly aligned with the surface.
This means the subtitles remain on top of the video in portrait
mode, rather than being huge and below it.
