Direct play only. The server is a headless GPU-less Xeon: nothing is ever
transcoded or remuxed. A file either plays in the client or it does not.
Measured, not assumed (ffmpeg-generated files with known codecs, played through
Vellum's own stream endpoint in Chrome 155 / Linux):
mp4 h264+aac plays mkv h264+aac PLAYS <- container is fine
mov h264+aac plays webm vp9/opus plays
mp4 av1+opus plays webm vp8/vorbis plays
mp4 hevc+aac AUDIO ONLY, videoWidth stays 0, no error
mkv hevc+flac AUDIO ONLY
avi mpeg4+mp3 fails outright
All seven audio formats play. Two conclusions drive the design: codec matters
and container barely does (mkv+h264 plays, mp4+HEVC does not), and canPlayType
is unreliable in both directions — it says "no" for mov+h264 (which plays) and
"maybe" for mkv+hevc (whose video never decodes).
Therefore playability is a property of the CLIENT, not the file. The server
never declares a file playable; it reports codec facts and each client decides.
That is what makes adding mpv/libvlc/MDK later a matter of registering an engine
rather than re-architecting.
Wave 4 - audio depth
- New MusicPlayer.svelte: real queue, shuffle that walks a fixed permutation
(so "previous" means something and nothing repeats early), repeat off/all/one,
per-track rows, album art, next-track preload.
- AudiobookPlayer: MediaSession (OS media keys + lock screen), playback speed
that SURVIVES a chapter change and persists, sleep timer with countdown that a
manual pause cancels, keyboard shortcuts, next-chapter preload.
- Shared mediaSession.ts written by the coordinator before dispatch so both
players consume one implementation instead of inventing two.
Wave 5 - ffprobe facts
- internal/probe (ffprobe wrapper, optional dependency), migration 0010 adding
vcodec/acodec/width/height/probed_at to media_files, scanner hook, API fields.
- Probing runs only for NEW or CHANGED files and BEFORE the write transaction
opens, so it can never hold SQLite's write lock and a rescan never becomes a
full-library ffprobe sweep. Proven: 797ms probing scan, then 1ms rescan with
probed_at byte-identical.
- ffprobe skips attached_pic so an mp3 with cover art reports no video codec.
- Fixed a real hole: .avi is in the video registry but had no MIME entry, so it
was served as application/octet-stream and could never play.
Wave 6 - the video player
- VideoPlayer.svelte with resume, progress + keepalive final flush, MediaSession,
keyboard shortcuts, multi-file picker, and codec facts shown.
- The honest path is the feature: an HEVC file makes Chrome play audio over a
blank frame with no error, which is the worst possible outcome. The player
detects it and says so, naming the codec and pointing at clients that can.
Coordinator fix to Wave 6: the agent's detection hung off `loadedmetadata`, but
an explicit `type` the browser cannot satisfy makes it reject the source during
selection, so NEITHER loadedmetadata NOR error fires — and the player showed a
working-looking 0:00 with a Play button, exactly the silently-broken state the
component exists to prevent. Added a load watchdog: if the element says nothing
within 2.5s, the source was rejected and the honest notice is shown. Verified
per file afterwards (h264/mkv play at 640 wide; hevc and mpeg4 show their
notices).
Verified end to end, not just compiled: 15 packages pass (including the new
internal/probe), gofmt/vet clean, svelte-check 0/0, and every claim above checked
against a running server. Note the demo's own mp3s are 100 KB of random bytes and
cannot decode; the audio players were proven against generated real audio instead.
The landing screen now reads as a product rather than a list.
- migration 0006: item_views, per user. "Most viewed" is personal — what I
re-read is not what you re-read. Counted when an item is opened in a reader,
so the number means consumed, not merely fetched.
- Suggestions: unstarted items related to what the user has been consuming —
same author first, then same kind, then recent as a floor. Each carries the
reason it was chosen ("More by Daft Punk"), because a suggestion nobody can
understand is noise.
- Explore: a mixed sample across every kind, excluding in-progress items so the
zone is discovery rather than a repeat.
- Home fetches all five shelves in one request; the screen never pops in.
- web: Shelf gained subtitle/badge support, Card gained a subtitle, and the
home renders four shelves plus a wrapping Explore grid.
Three bugs found and fixed while verifying:
- Continue showed a multi-track audiobook once per chapter. GROUP BY item_id
with MAX(updated_at) picks one card per item (SQLite takes the bare columns
from the row that produced the max).
- Suggestions and Explore passed their SQL arguments in the wrong order: the IN
list precedes the user id in those queries, so a user id was being bound as a
library id. Covered by a scoping test that would have caught it.
- The sidebar lost its media types on a cold, logged-out load. bootstrap()
fetched media types inside a Promise.all with /auth/me, so the expected 401
rejected the whole thing and nothing refetched after login. Media types are
public and now load independently.
The app looked like an admin panel. This is the product people actually see
when they open their library.
- Home: a landing screen with a Continue shelf (progress bars, straight from
the progress table) and per-type shelves of recent additions. One request
feeds it, so it does not pop in piece by piece.
- Browse: cover grid per media type with type chips, plus browse-all. Powered
by a new GET /items that lists across every visible library, filtered by
kind, through the same access chokepoint.
- Item page: cover, kind, title, authors, progress, a primary action that says
Continue when you have started, description, and the file list for
multi-file items. Cards now open the item page rather than jumping straight
into a reader.
- Search: results grouped by media type, cover-forward.
- Navigation moved from "libraries" to "media types" — you browse Ebooks, not
"the Ebooks folder". Libraries became an admin concern.
- Design system: dark by default, cover-forward, one accent, tighter type
scale, horizontal shelves, skeleton loaders.
- media: GET /home, GET /items, and authors on item detail.
Verified by screenshot in a live instance: home shelves, browse grid, and item
page all render correctly.
A book is a folder of chapters, not a file. The scanner gained a grouping
mode so a directory of tracks becomes one item with ordered files.
- registry: MediaType.Group (file | directory). Audiobooks and music group by
directory; everything else stays one item per file.
- scanner: builds groups, upserts one item per group, marks items missing when
their directory disappears, and keeps the file-level added/updated/missing
accounting. Tracks are ordered naturally, so chapter 2 precedes chapter 10.
- natsort: one shared natural-order comparator, now used by both the scanner
and the comics module (which had its own copy).
- media: GET /items/{id}/files/{fileID} streams one specific track. It
verifies the file belongs to the item, so an item id cannot be paired with
another item's file id.
No new module was needed for playback: the polymorphic progress table already
keys on file_id, so per-chapter resume fell out of the existing design. The
web player resumes the exact track and offset.
Verified: 3 chapters grouped into one book titled "Mistborn", natural order,
range request returned 206, mismatched file id 404s, per-track progress
round-trips.
- stream: serving goes through http.ServeContent, so Range/If-Range/
If-Modified-Since are correct for every media type by construction
- progress: the polymorphic store. One row per user/item/file; the PK includes
the file so multi-track audiobooks resume per track later. Finished is
inferred when position reaches duration.
- media: generic item endpoints (detail, file, cover, progress, recent). Every
one routes through auth.CanAccessLibrary; an unauthorised item 404s.
- covers: a per-kind extractor registry. Extraction is lazy and recorded in
the assets table. A missing cover is a placeholder, never a 500.
- modules/ebooks: EPUB parsing (container.xml -> OPF -> metadata, spine, cover
with three fallback strategies), cover extraction to /config, and lazy
metadata parsing so parser fixes need no rescan.
Verified against a generated EPUB: title/2 authors/language/publisher/spine,
cover served as PNG, range request returned 206 with correct Content-Range,
progress round-tripped.
