Async decoding

Decodes cover art off the main thread so the seek line does not stutter.

Now Playing on a phone: the cover, the title and artist, a seek bar, and the play controls — The large cover decodes off the main thread when the track changes.

How Riff uses it

Every image the player prints carries decoding="async": the large cover and the two thumbnails in the template, each row and queue item, and each library card. The off-screen image loaded to sample a cover's colour sets it too.

Why

The cover swaps on every track change while the seek line is animating each frame, and a synchronous decode would drop a frame.

Without it

Browsers without the hint decode as usual.

Where

plugins/riff/templates/player.php, line 89

<img class="riff-cover" data-riff-art data-riff-size="large" alt="" decoding="async" draggable="false" hidden>

plugins/riff/assets/riff.js, line 1427
```
img.decoding = 'async';
```

Links open the source at the commit this page was published from.

Reference: Async decoding on MDN.