The AV1-only publish lasted four hours in the wild: the first viewer on
mobile Safari got "bad media error" from the raw file, because a post's
link is fetched raw — Lemmy apps and browsers play that exact URL, with
no <source> negotiation in front of it. The previous commit's note
("--raw ... if that audience matters") had it backwards: the audience
that cannot play AV1 is not a per-post judgement call, it is whoever
happens to open the thread on an iPhone.
So publish-media.sh now emits two encodings and points the post at the
compatible one:
* Every video transcode also produces <hash>.h264.mp4 (x264 crf 23,
same denoise, same frames), uploaded beside the AV1 under the AV1's
hash — the poster's sibling-naming trick, reused, so fetch-media.sh
finds it by name with nothing to look up.
* The printed URL to paste into the post is the H.264 one. pict-rs
can thumbnail it too, so instance thumbnails come back as a bonus.
fetch-media.sh adopting an own-origin .h264.mp4 URL swaps the AV1 back
in as the page's primary when it is on the mount, and records the H.264
as `fallback` in posts.json. The renderer turns a non-empty fallback
into a <source> pair: the AV1 first with an explicit codecs parameter —
both files are video/mp4, so the parameter is the only thing that lets
a non-AV1 browser skip to the file it can play — and the H.264 second.
Browsers with AV1 keep downloading the small file; Safari before 17
gets one that plays instead of an element that will not.
e2e gains the matching conditional gate: a page offering an av01
<source> must offer an .h264.mp4 one, so an AV1 video can never again
ship without its fallback.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
