Captions during HLS playback flash/are difficult to readily
https://bugs.webkit.org/show_bug.cgi?id=133365
<rdar://problem/16584132>
Reviewed by Eric Carlson.
Correct two problems:
1. Add new logic to handle cues that are identical to existing cues, except
that they cover a slightly later moment in playback. For example, a cue
encoding device might emit a cue at 24 fps, with many of the cues containing
the same content but covering only 1/24th of a second.
Rather than hiding and displaying our cues at the cue encoding rate, we should
simply continue to display the same cue as long as the content is unchanged.
2. The cue "isEqual" logic for TextTrackCueGeneric improperly short-circuited the
VTTCue isEqual logic. This was done to avoid a false failure due to the cue
type being 'generic' rather than 'vtt', but incorrectly treated cues with
non-matching text as equal.
* html/track/DataCue.cpp:
(WebCore::DataCue::cueContentsMatch): Move cue comparison code to new method that
doesn't check that the 'type' of the cue is identical.
(WebCore::DataCue::isEqual): Modified to use new 'cueContentsMatch' method.
(WebCore::DataCue::isStartOfCue): Confirms cues match except for start and end times.
* html/track/DataCue.h:
* html/track/TextTrack.cpp:
(WebCore::TextTrack::hasCue): Modify to check if a new cue is simply a continuation
of an existing cue.
* html/track/TextTrackCue.cpp:
(WebCore::TextTrackCue::cueContentsMatch): New method containing the equality code
that used to live in 'isEqual'.
(WebCore::TextTrackCue::isEqual): Modified to use new 'cueContentsMatch' method.
(WebCore::TextTrackCue::isStartOfCue): Confirms cues match except for start and
end times.
* html/track/TextTrackCue.h:
* html/track/TextTrackCueGeneric.cpp:
(WebCore::TextTrackCueGeneric::cueContentsMatch): New method containing the equality
code that used to live in 'isEqual'.
(WebCore::TextTrackCueGeneric::isEqual): Modified to use new 'cueContentsMatch' method.
(WebCore::TextTrackCueGeneric::isStartOfCue): Confirms cues match except for start and
end times.
* html/track/TextTrackCueGeneric.h:
* html/track/VTTCue.cpp:
(WebCore::VTTCue::cueContentsMatch): New method containing the equality code that
used to live in 'isEqual'.
(WebCore::VTTCue::isEqual): Modified to use new 'cueContentsMatch' method.
(WebCore::VTTCue::isStartOfCue): Confirms cues match except for start and end times.
* html/track/VTTCue.h:
git-svn-id: http://svn.webkit.org/repository/webkit/trunk@169440 268f45cc-cd09-0410-ab3c-d52691b4dbfc
10 files changed
