With reference to #8025, this is a partial proposal to see if this style
of extensible customisation could be favourable to the shaka-player
community:
Proposal for some accessibility options whereby an App builder can
customise subtitle/caption size, with the potential of an App offering
accessibility options for text size.
This style could be used for other text styling attributes in a similar
way, but this is just the first step.
---------
Co-authored-by: Álvaro Velad Galván <ladvan91@hotmail.com>
Fixes https://github.com/shaka-project/shaka-player/issues/8087
Implements handling of multiple samples in a MP4/ISOBMFF/DASH TTML
segment/fragment. Such segments are allowed by ISO14496-12 and
ISO23000-19. gpac creates such segments. The prior code just treated the
full MDAT as one TTML XML document and tried to parse it in whole
without accounting for sample(s). A testcase is included which was
created by taking the testdata from ttml-segment.mp4 and splitting the
subtitles into two independent TTML-XML documents, which then were put
as individual samples.
The testdata for the prior existing multiple MDAT testcase was invalid.
It was created by taking the same ttml-segment.mp4 as a source and just
duplicating the MDAT box, but without then also fixing the TRUN box. The
duplicated data was thus not referenced. The test case still worked,
because the prior code did not look at the TRUN box and the sample
specification at all and just handled any full MDAT box = 1 sample. The
testdata was replaced with a new file, which is basically the same as
for the multiple samples case, but with the two samples split into two
MDAT boxes.
Adds a replacement for removed JSDoc checks from ESLint v9.
Additionally fixes lots of issues found in the JSDoc, such as:
- missing `@param`/`@return` annotations
- bad formatting
- params order
- param name in the same line as type definition (tried to disable it,
but it was causing other issues and we didn't have lots of places with
such formatting)
Minor fixes in code found by Closure Compiler after fixing JSDoc are
also included.
Chromium browsers do not currently support the `lineAlign` or
`positionAlign` properties on the VTTCue class, just like the region
property. So this pull request adds an if before reading those
properties so that the position and line values are handled correctly in
UITextDisplayer (without this change the subtitles are always at the
bottom edge of the player and right aligned subtitles are displayed
off-screen).
https://developer.mozilla.org/en-US/docs/Web/API/VTTCue/lineAlign#browser_compatibilityhttps://developer.mozilla.org/en-US/docs/Web/API/VTTCue/positionAlign#browser_compatibility
Before fix
After fix
Steps to reproduce:
- Get local demo running (`python build/all.py --debug`?)
- Visit custom content, add
https://d2zihajmogu5jn.cloudfront.net/elephantsdream/ed_hd.mp4 (with
whatever name)
- Add track below
- Start playing custom video, switch Captions to the new text track
**JS to add text track**
```js
await document.getElementById('video').ui.getControls().getPlayer().addTextTrackAsync('data:text/vtt;charset=utf-8,WEBVTT%0AKind%3A%20subtitles%0ALanguage%3A%20en%0A%0A00%3A00%3A00.000%20--%3E%2000%3A01%3A00.000%20align%3Astart%20position%3A0%25%20line%3A0%25%0ATop%2FLeft%0A%0A00%3A00%3A00.000%20--%3E%2000%3A01%3A00.000%20line%3A0%25%0ATop%2FCentre%0A%0A00%3A00%3A00.000%20--%3E%2000%3A01%3A00.000%20align%3Aend%20position%3A100%25%20line%3A0%25%0ATop%2FRight%0A%0A00%3A00%3A00.000%20--%3E%2000%3A01%3A00.000%20align%3Astart%20position%3A0%25%20line%3A48%25%0AMiddle%2FLeft%0A%0A00%3A00%3A00.000%20--%3E%2000%3A01%3A00.000%20line%3A48%25%0AMiddle%2FCentre%0A%0A00%3A00%3A00.000%20--%3E%2000%3A01%3A00.000%20align%3Aend%20position%3A100%25%20line%3A48%25%0AMiddle%2FRight%0A%0A00%3A00%3A00.000%20--%3E%2000%3A01%3A00.000%20align%3Astart%20position%3A0%25%0ABottom%2FLeft%0A%0A00%3A00%3A00.000%20--%3E%2000%3A01%3A00.000%0ABottom%2FCentre%0A%0A00%3A00%3A00.000%20--%3E%2000%3A01%3A00.000%20align%3Aend%20position%3A100%25%0ABottom%2FRight%0A%0A', 'en', 'subtitles', 'text/vtt')
```
Font settings were applied to ".shaka-video-container *", all
descendents of .shaka-video-container. This meant that the font setting
inheritance intended in our UI text displayer was broken, because those
descendents effectively had their own settings and didn't inherit them
from their parents in the subtitle DOM hierarchy. We fix this by
breaking down the CSS and applying those font settings directly to the
top level .shaka-video-container, to be inherited by any descendent
without their own setting.
> Quote from specs:
> Valid examples include:
> • "stpp.ttml.etd1" - TTML content suitable for presentation by an
EBU-TT-D renderer
> • "stpp.ttml.etd1|im1t" or "stpp.ttml.im1t|etd1" - TTML content
suitable for presentation by an EBU-TT-D or
IMSC1 renderer
Fixes#6831
David HM Morgan
Álvaro Velad Galván
Juliane Holzt
Wojciech Tyczyński
PikachuEXE
Gary Katsevman
Wojciech Tyczyński
MichaelSweden