## What
Allow Studio Preview to serve an asset reached through a project-local symlink whose target is in a shared directory outside the project, including browser-hostile video assets that need an authoring proxy.
## Why
Preview rejected these assets with a 404 while the renderer accepted the same path. The initial static-route fix still failed for HEVC, ProRes, AV1, and VP9 assets because the proxy transcoder rejected the external target.
## How
Use lexical project-root containment for the read-only static asset route and proxy source request. The transcoder canonicalizes the target for ffmpeg and includes that identity in its cache key, while keeping the proxy cache inside the project. Composition source paths retain canonical containment because preview can persist their data-hf-id values.
## Test plan
- [x] Unit tests added/updated
- [x] `bun run --cwd packages/studio-server test` (397 tests)
- [x] Studio Server typecheck, oxlint, and oxfmt
- [x] External-symlinked hostile-video proxy route regression
- [x] Static-route traversal regression
- [ ] Documentation updated (not applicable)
* feat(media): alpha-capable authoring proxies
Alpha sources were refused a proxy before the codec map ever asked whether the
browser could decode them, so a ProRes 4444 alpha file (which no browser
previews at all) rendered black forever, while an alpha WebM (which previews
fine) was already covered by the browser-safe check on the next line. The alpha
veto earned nothing and cost the one case that needed help.
Alpha is now a target-codec choice rather than a veto: alpha sources transcode
to VP9 + yuva420p in WebM, everything else keeps the existing H.264/MP4 path
byte for byte. Only files no browser can preview are proxied, which is the rule
the runtime already followed everywhere else.
WebM cannot carry AAC, so the VP9 path uses Opus and drops the MP4-only
faststart flag. PROXY_PARAMS_VERSION moves to v3 so clients stop serving the
previously cached proxies.
Safari does not decode VP9 alpha and still shows black for alpha sources, as it
does today: this is better on Chromium and Firefox and no worse anywhere.
* fix(media): infer proxy variant for rescue
* fix(media): preserve alpha proxy hardening after restack
* feat(studio-server): serve H.264 proxies from the preview route
Wires the codec manifest and the transcoder into the preview surface: the route
negotiates a proxy via a query param and serves it through the existing range
and ETag machinery, composition HTML carries a codec map for the runtime, and
hostile assets pre-warm so a first play does not wait on a cold transcode.
Exposes the three subpath exports the CLI surfaces consume upstack.
Drops the TEMP fallow entry added with the transcoder: it has real importers now.
* fix(studio-server): publish media proxy exports
* fix(parsers): scan HTML comments linearly
* feat(cli): let projects opt out of automatic proxying
Adds media.autoProxy to hyperframes.json plus --proxy/--no-proxy flags, and
forwards the resolved value into the studio and preview servers and the vite
adapter. Lands before the runtime slice that turns auto-proxying on, so the
switch exists before there is any behavior to switch off.
* fix(cli): align media config schema
* feat(core): swap undecodable video to its proxy at runtime
Adds the browser-side half: before first load the runtime consults the injected
codec map and swaps a hostile source to its proxy, and if a video still reports
zero decodable width it rescues it reactively. An HEVC file carrying AAC fires
no error event, so zero videoWidth, not the error event, is the reliable signal.
Audio elements and alpha sources are never proxied, render mode never proxies,
and each swap evicts the element's stale sync state and reports once.
This completes the loop: auto-proxying is live for preview and studio from here.
The opt-out (media.autoProxy, --no-proxy) shipped in the previous slice.
* feat(cli): serve proxies from play, present, and the static project server
Adds proxy negotiation to the CLI-side servers and gives play byte-range
serving it never had, so a swapped video can seek. The static project server
behind check, snapshot, compare and friends injects the codec map once, so all
of its callers inherit the behavior; snapshot forwards its own proxy flag.
* fix(cli): serve proxies for camera formats
* feat(studio-server): serve H.264 proxies from the preview route
Wires the codec manifest and the transcoder into the preview surface: the route
negotiates a proxy via a query param and serves it through the existing range
and ETag machinery, composition HTML carries a codec map for the runtime, and
hostile assets pre-warm so a first play does not wait on a cold transcode.
Exposes the three subpath exports the CLI surfaces consume upstack.
Drops the TEMP fallow entry added with the transcoder: it has real importers now.
* fix(studio-server): publish media proxy exports
* fix(parsers): scan HTML comments linearly
* feat(studio-server): bound the proxy cache with LRU accounting
Adds cache accounting and bounded cleanup for transcoded proxies, and keeps
.transcode-cache out of git. Standalone: the transcoder consumes it next.
* feat(studio-server): transcode bounded H.264 proxies on demand
Adds the proxy transcoder: a bounded work queue with per-key dedupe, a hard
kill ceiling, TTL'd failure memory so a broken asset is not retried forever,
and pixel/color normalization for browser playback. Writes through a temp name
and renames on success, so a cache entry is never partial.
Carries a TEMP fallow ignoreExports entry: this module lands below its
consumers, so a per-PR audit sees its exports as unused until the preview weld
arrives. The entry is dropped there.
* feat(studio-server): probe media codec facts for proxy decisions
Adds the codec manifest: one ffprobe-backed answer to what codec an asset
uses, whether a browser can decode it, and whether it carries alpha. Migrates
the existing prober to the shared ff-binaries resolver and to async execFile so
a scan pool runs off the event loop. No consumer yet; the preview weld wires it
up later in the stack.
* fix(studio-server): honor injected ffprobe runners
The runtime picker built raw `#${id}` selectors while its sibling
attribute-selector branches (data-composition-id, data-composition-src,
data-track-index) already CSS.escape'd their values. When a user
composition has an element with a digit-leading id (e.g. `id="0"`),
the picker emits the selector `#0` which is invalid per the CSS spec —
downstream `document.querySelector` throws SyntaxError.
Same failure mode reached the Studio thumbnail: getElementScreenshotClip
called `document.querySelectorAll(selector)` unguarded, so an invalid
selector bubbling out of page.evaluate failed the whole thumbnail and
returned 500 to the browser (broken thumbnail image).
Fixes:
- packages/core/src/runtime/picker.ts — CSS.escape the id, matching the
sibling branches on lines 100/102/104.
- packages/studio-server/src/helpers/screenshotClip.ts — catch
SyntaxError from an invalid selector and return undefined so the
caller falls back to a full-page screenshot, so the user still sees
a thumbnail instead of a broken image.
Regression tests for both.
Reported via #hf-cli-feedback (Slack ts=1784218060, darwin/arm64,
CLI 0.7.60): "digit-leading worker IDs broke Studio thumbnail
querySelectorAll".
— Via
Addresses R2 CHANGES_REQUESTED from Miga + Rames on PR #2529:
1. Sibling-surface gap (blocker): `hyperframes cloudrun render{,-batch}`,
`hyperframes lambda render{,-batch}` all advertised the same tier-only
aliases (`1080p` / `hd` / `4k` / `uhd`) but normalized them to `landscape`
and never set `outputResolutionAspectAgnostic`. The distributed plumbing
PR #2529 added received `undefined` from those callers, so portrait `1080p`
still hit the original aspect-mismatch on Cloud Run / Lambda.
Fix: introduce `resolveResolutionFlagPair` in `@hyperframes/parsers` (the
single source of truth for the two-step normalize + aspect-agnostic
detect) and route every distributed entrypoint through a shared
`parseOutputResolutionFlag` CLI util so the alias signal now reaches
`SerializableDistributedRenderConfig`. Studio Server keeps its
canonical-only HTTP contract; that intent is now pinned in tests.
2. Preflight recompute (hardening): the earlier "downgrade aspect-mismatch"
preflight cleared un-remapped mismatches, so IG 4:5 (non-preset aspect,
no sibling) and portrait-4K comp + `--resolution 1080p` (remap +
downsample) both slipped through to fail late in `resolveDeviceScaleFactor`.
Now `checkRenderResolutionPreflight` computes the effective preset via
`suggestMatchingPreset` (mirroring the compile stage's
`adaptAspectAgnosticResolution`) and re-checks against that — only
genuinely-fixable mismatches clear early. New tests pin both regressed
input classes.
3. Docker forwarding boundary test (Miga's important #2): pinned
`1080p` survives verbatim as `--resolution 1080p` in the Docker args
so the in-container CLI can re-run `isAspectAgnosticResolutionAlias`.
4. Doc-nit (Miga): parsers/src/types.ts no longer references the
nonexistent `resolveResolutionForComposition` — points at the actual
remap helpers.
Fallow: cloudrun.ts / lambda.ts share 390 lines of pre-existing structural
symmetry (parallel AWS + GCP dispatchers), and lambda/render.ts +
render-batch.ts declare parallel RenderArgs interfaces. Both re-flagged
after threading the aspect-agnostic field through each surface; ignored
with justification in .fallowrc.jsonc. lambda.ts's `run` and
lambda/render.ts's `waitForCompletion` are pre-existing CRAP-score
hotspots untouched by this PR — added under health.ignore.
Co-Authored-By: Claude <noreply@anthropic.com>
— Via
James