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videojs / videojs-contrib-hls

HLS library for video.js
http://videojs.github.io/videojs-contrib-hls/
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Live 608 captions #849

Closed jamsterdam29 closed 7 years ago

jamsterdam29 commented 7 years ago

Description

Have been looking at a live test stream with 608 captions and while the captions are converted into VTTCues, the display does not fully reflect the 608 display. I know webvtt does not have the idea of "roll-up" captions, but what is the expectation for how live captions should display?

It might be ok if live captions did not fully reflect 608, but sometimes it makes them hard to read. Sentences are split in weird places, the centering of all lines makes more difficult to follow, and some lines appear and disappear too fast.

This may be more of a question of how 608 is interpreted and converted, what the expectation is, and if there is any way to improve. Thanks.

Sources

Steps to reproduce

play a live stream with live programming (sports, news, etc...) and compare to 608 native display (vlc seems to display based on native 608 codes).

Results

Expected

Error output

Additional Information

videojs-contrib-hls version

what version of videojs-contrib-hls does this occur with? videojs-contrib-hls x.y.z

videojs version

what version of videojs does this occur with? video.js 5.11.6 videojs-contrib-hls 3.5.3

Browsers

Platforms

Other Plugins

videojs-contrib-ads 3.3.11 videojs-ima 0.4.0

Other JavaScript

dmlap commented 7 years ago

Our goal for converting CEA-608 would be to follow the current W3C spec so if you see particular instances we're not achieving that, please file separate issues for any you find. We are missing support for parsing some of the positioning and formatting commands in CEA-608 as well as paint-on mode today. If you're interested in helping out with that, please check out mux.js!