c1c110e3d2
* fix(player): keep text subtitles in sync across copy-mode restarts and sparse cue windows - Rebase already-loaded cues in place when streamOriginSeconds changes (copy-mode session restart) instead of leaving them offset by the delta. - Stop inferring end-of-input from where a window's cues stop; only the known media duration marks EOF, so a dialogue gap no longer silently ends prefetching for the rest of playback. - Anchor the first window fetch to the intended start position (resume target or pending seek) while the element still reports currentTime=0, and reset coverage on forward seeks past the fetched window. * fix(playback): align encoded transcode start with the declared segment boundary A mid-segment start (resume, seek restart, audio switch) spawned ffmpeg at the raw seek position while labeling its first segment with the grid number, whose synthetic-manifest start is up to one segment earlier. hls.js aligns the first fragment's content to that declared position, shifting the whole session's timeline late by seek mod segment_duration (0-2s): subtitles trail dialogue by a constant per-session offset and progress/resume positions drift by the same amount. Snap the ffmpeg start position down to the segment boundary for encoded sessions so declared and produced timelines match exactly; the player still seeks to the precise requested position. Copy-mode sessions serve ffmpeg's real manifest and keep the raw seek. * fix(api): forward http.Flusher through response-writer middleware wrappers Streamed subtitle extracts (and any progressive response) flush per chunk via an http.Flusher assertion, but none of the status-capturing middleware wrappers implemented Flush, so the assertion failed and cues sat in Go's response buffer until ffmpeg finished. On large remuxes where a 600s window takes 20s+ to demux, captions appeared only when the whole window completed instead of within the first seconds. Give every wrapper a Flush() (satisfies plain assertions, including chi's Compress) and Unwrap() (satisfies http.ResponseController). The jellycompat image-proxy tag rewriter flushes only in passthrough mode since it buffers JSON bodies for rewriting. Regression test asserts the API chain forwards Flush end to end. * feat(player): PGS subtitles honor size, position, and background settings Port the tvOS/iOS bitmap-cue styling to the web player. libpgs now decodes in worker mode but draws to a hidden source canvas on the main thread; a compositor detects cue regions from the frame's alpha channel and re-places them on a visible overlay canvas per the shared subtitle appearance settings: size scale (with the 0.85 authored-size compensation), vertical position preset (dialogue-band cues only — floating signs keep authored placement, matching the Apple implementation), and the background box. Font family, text color, and outline are baked into the source pixels and remain inapplicable. * fix(player): anchor PGS position presets to the text overlay's reference frame The initial port used silo-apple's 30/1080 bottom margin and video-relative lower-third/top anchors; the web text overlay anchors to a 16:9 reference frame with 7%/18% offsets that extends into the letterbox for wide content. Use the same anchors so PGS dialogue lands exactly where SRT text does. * feat(player): size PGS cues to match the text subtitle line height Replace the authored-size ladder (0.85 × font-size ratio) with per-cue text-line matching: the region detector reports the tallest text line inside each cue, and the compositor scales the cue so one line of bitmap text renders at the same pixel height as the SRT overlay's font at the current preset. Authored size differences between discs no longer leak through; upscaling is capped at 2.5× to keep small bitmaps from going blurry. * feat(subtitles): opt-in windowed PGS extraction to cut mid-file load latency PGS extracts always demuxed the source from byte 0, so starting a large remux mid-file meant minutes before the first bitmap cue. The web player now opts in to windowed extraction (?windowed=1&position=&duration=) and re-points libpgs at a fresh window on seeks and near coverage end; ffmpeg input-side -ss with -copyts keeps absolute source timestamps. Without the explicit opt-in the endpoint behaves byte-identically, so Apple/Android and other single-fetch consumers are unaffected. ASS remains unconditionally non-windowed (its header only exists at offset 0). * feat(playback): cache extracted PGS subtitle tracks Every selection of an embedded PGS track re-ran a full ffmpeg extract that demuxes the entire source file from byte 0 — minutes for a large remux — and responses were Cache-Control: no-store, so repeat selections, re-watches, and multiple viewers all paid full price. Add a disk cache for full-track .sup extracts under <transcode_dir>/subtitle-cache, created lazily: - Keyed by source path hash + subtitle stream ordinal + source mtime+size (encoded in the filename), so a replaced source file implicitly invalidates its entries; the source is stat'ed on every lookup. - Cache miss: ffmpeg stdout is teed to the response (first viewer still streams progressively, first-byte latency unchanged) and into a temp file that is fsynced and atomically renamed into the cache on clean ffmpeg exit. Any error — ffmpeg failure, client disconnect, tee write failure, or the source changing mid-extract — discards the temp file, so a partial entry is never served. - Cache hit: served via http.ServeContent (Range support, Content-Length, Last-Modified from the source mtime) with a revalidatable Cache-Control instead of no-store. - Concurrent requests for the same in-flight track run their own uncached extract (mutex + in-flight key set) rather than blocking on another client's connection. - Scan-on-commit LRU eviction under a 2 GiB cap (recency tracked by bumping entry mtime on hit; atime is unreliable under relatime), plus sweep of crash-orphaned .part temp files. - Windowed PGS requests (?windowed=) bypass the cache in both directions: their output covers only a slice of the track. Both the integrated API handler and the standalone proxy subtitle path share the same playback.SubtitleCache.ServeSUPExtract helper. VTT (already windowed and fast) and ASS (small) stay uncached. No API surface change. AI-use disclosure: implemented with Claude Code. * fix(playback): check Close error returns in subtitle cache paths Silence errcheck on the cache-hit defer and the test's simulated disk-full Close. AI-use disclosure: implemented with Claude Code. * feat(playback): warm PGS cache in background and window from cached track Windowed PGS requests bypassed the cache entirely, so every window fetch re-demuxed the multi-GB original file. Now a windowed miss kicks off a detached background warm (full-track extract into the cache, at most 2 concurrent server-wide, coalesced with client-driven fills), and once the entry exists windowed extracts read the 15-80MB cached .sup instead — seeks and re-enables become near-instant after the first load. Verified empirically that ffmpeg preserves absolute PTS when windowing a sup input. * feat(player): hold playback while PGS subtitle cues load When a PGS track is enabled (or a seek lands outside the fetched window), extraction takes seconds and dialogue could play unsubtitled. The player now pauses until the renderer's parsed data covers the playhead — tracked via libpgs' parsed-timestamp watermark, the exact predicate it renders by — showing a "Loading subtitles…" indicator after 500ms. User play/pause always wins over the hold, a 20s safety timeout prevents stranding playback, and background prefetch never pauses. If future libpgs versions reshape the observed internals the hook degrades to the old play-through behavior. * perf(player): shrink uncached PGS window to 600s Draining a windowed extract from the source reads the full interleaved container across the window (~1GB per 100s of remux on measured hardware); a 3600s window cost ~12GB of reads per fetch while cold. Once the server cache is warm a window costs milliseconds regardless of size, so smaller windows only add trivially cheap re-fetches. * feat(subtitles): burn in PGS/bitmap subtitles for the web player The web player rendered PGS client-side via libpgs, which required extracting the .sup track — a cold ffmpeg demux that took seconds even windowed, since c:s copy still reads the whole interleaved container up to the playhead. Every other server (Plex, Jellyfin default, Emby) burns image subtitles into the video instead, and that is the only path with no per-seek extraction cost. Selecting a bitmap subtitle (PGS/DVD/DVB) now restarts the transcode with subtitle_burn_in at the current aligned position, reusing the same restart machinery as an audio/quality switch so the segment-boundary timeline alignment holds. The server composites the decoded subtitle onto the video with an overlay filter_complex graph (libass's subtitles= filter is text-only); overlay runs at native resolution before any target scaling, and hardware pipelines round-trip through CPU like the text path. Burn-in forces a video encode, so copy-video recipes are upgraded to h264 both client- and server-side. Text subtitles keep the instant, styled, client-side path. The .sup streaming endpoints, cache, and windowing are retained for the Apple client, which renders PGS natively. The now-dead web PGS stack (usePGSSubtitles, pgsPlacement, libpgs dep) is removed. Tradeoff: bitmap subtitles no longer honor web appearance settings (baked into the video) and toggling one restarts the transcode (~1-2s buffering), matching Plex behavior. * fix(player): rebuild text subtitle track when turning off PGS burn-in Selecting an SRT track that turned off bitmap burn-in restarted the transcode, and the client TextTrack built in that same moment was orphaned when the <video> element reloaded, so the subtitles never rendered (and a seek could not recover the dead track). Rebuild the text track once the new stream settles, gated on the burn-in-off transition so quality/audio switches and copy-mode seek restarts keep their subtitles without a needless re-extract. * fix(player): render web subtitles behind the control HUD The text subtitle overlay sat at z-20, above the controls layer (z-10), so cues painted over the bottom HUD and cluttered the control bar. Drop it to z-[5] — above the video, below the controls — so the HUD paints over the cues while it is visible. When controls are hidden the whole controls layer is opacity-0, so cues remain fully visible. * feat(player): lift web subtitles above the control bar while it's visible Rather than hiding bottom-anchored cues behind the HUD, raise them just above the control bar (measured height + a small gap) whenever the bar is visible in the foreground player, then settle them back when it hides. The bar is a roughly fixed pixel height while the cue offset scales with the player, so the bar is measured via ResizeObserver rather than hardcoded. Top-anchored cues never collide with the bottom HUD, so they stay put. z-[5] is retained as a safety so any residual overlap tucks behind the bar. * fix(player): coalesce same-tick transcode restarts into one dispatch Starting playback with a persisted bitmap subtitle fired transcode/start twice within milliseconds: the auto-start effect dispatched before subtitle auto-selection restored the burn-in, whose effect then forced a second start. The first request was already on the wire (no abort signal was passed to fetch), so the server spawned an ffmpeg only to kill it for the second start — visible in production as an ffmpeg exit error ~1ms after every such session start, and slowing time to first frame. Defer the network dispatch by one macrotask so back-to-back restart calls in a tick collapse into a single request carrying the final parameters; state updates stay synchronous. Pass the abort signal into playerFetch so a superseded in-flight request is actually cancelled, and drop any deferred dispatch on unmount so a stray transcode/start cannot land after the session's exit DELETE. * fix(catalog): resolve effective subtitle defaults for movie item details Movie pre-play subtitle selectors were missing the effective defaults (including per-item overrides saved from a previous play) that episodes and watch payloads already resolve. Extract applyToItemDetail/ applyToWatchDetail helpers and apply defaults for movies in buildMediaItemDetail. The SubtitlesPopover now also eagerly loads downloaded subtitles when the saved preference points at one so the closed trigger's Auto summary reflects the override. * feat(player): scale subtitle font size with the rendered video Replace fixed rem font sizes with px values defined at a 720px 16:9 reference height, scaled proportionally with the actually-rendered video (object-fit: contain) so subtitles keep the same relative size as the window grows or shrinks, with a 12px legibility floor. Rename useSubtitlePositionStyle to useSubtitleLayout, returning both the position style and the font scale, and add unit tests for the appearance helpers. * fix(player): satisfy strict index checks in transcode quality test * feat(player): let the pre-play Auto option clear the saved subtitle override A manual in-player subtitle selection persists as an 'always' override for that movie/series, but nothing in the UI could undo it — auto selection stayed pinned to the chosen track forever. Choosing 'Auto' in the pre-play subtitles popover now also deletes the stored preference (movie content ID / episode series ID) and invalidates item details so profile-level auto selection applies again. * feat(player): persist pre-play subtitle selections as the item override Choosing a track (or Off) in the pre-play subtitles popover only lived in component state: it applied to that playback session but vanished on returning to the detail page. Persist it through PUT /subtitle-prefs — the same 'always'/'off' override a manual in-player selection saves — keyed by movie content ID or episode series ID, and invalidate item details so the effective defaults reflect it immediately. * feat(ui): show the saved subtitle override and richer pre-play pill summaries A stored per-item override displayed as 'Auto: <language>', hiding both that an override exists and which track it is. The pre-play subtitle pill now shows the resolved track directly (name with (SDH)/(Forced) markers plus format, skipping markers the name already carries), the matching list row gets the checkmark instead of Auto, and the Auto row reads 'Reset to profile defaults'. Subtitle, audio, edition, and version pill summaries also truncate much later (max-w-44/sm:max-w-64). * fix(player): recover text subtitles from stream reloads and failed window fetches Three failure modes could silently freeze or stop web text subtitles: - A stream restart (seek-triggered transcode restart, quality/audio switch) reloads the <video> element and can orphan the programmatic TextTrack — cuechange stops firing and the last cue freezes on screen. Only the PGS-burn-in-off transition rebuilt the track. Now every settled stream URL change bumps the generation, and the rebuild carries loaded cues (converted back to source time) and window coverage over so it costs no refetch. - The sliding-window fetcher committed windowEnd before the fetch ran, so a failed or hung window counted as covered and was never retried — subtitles silently stopped for up to 10 minutes. Coverage now commits only after the window streams in fully; failures leave the range uncovered and retry after a 5s backoff. - A hung extraction (one fetch in flight at a time, no deadline) blocked every future window for the session. Reads now arm a 30s stall timer that aborts a response which stops delivering chunks; slow-but- progressing streams keep resetting it. Diagnosed from a session where ffmpeg took 69s to stream one subtitle window and a transcode restart landed mid-fetch, freezing the active cue. * fix(playback): keep subtitle selections stable across file changes * fix(web): clarify subtitle labels and positioning * fix(player): hide HUD when pointer leaves * fix(web): tidy subtitle track badges * fix(playback): remap audio tracks across file versions * fix(web): tidy audio track labels * docs(playback): clarify bitmap subtitle appearance * fix(playback): preserve selection state on restart * fix(http): preserve response state across flushes * fix(web): preserve pending quality for burn-in * fix(playback): preserve subtitle inventory identity --------- Co-authored-by: Quick <31828688+Quick104@users.noreply.github.com>
Silo
Silo is a self-hosted media streaming server for your movies, shows, music, and books. Point it at your media folders and stream to your devices — at home or away — with direct play, remuxing, and hardware-accelerated transcoding handled automatically.
Join the community on Discord. If Silo is useful to you, consider sponsoring the project — see Supporting Silo.
Highlights
- Plays your media, your way — direct play when the device supports it, remux or hardware-accelerated transcode (including NVENC) when it doesn't.
- Web app included — a full-featured web client and admin interface ship with the server.
- Works with apps you already use — optional Jellyfin/Emby-compatible API supports clients such as VidHub, Findroid, and Infuse.
- Household profiles — multiple profiles per account, with per-profile watch state and parental controls.
- Plugin-driven metadata — match and enrich your libraries with providers like TMDB and TVDB, installed as plugins.
- Fast setup — one
docker compose up -dbrings up the whole stack; everything else is configured in the admin UI.
Deploy with Docker (recommended)
The easiest way to run Silo is with Docker Compose. The default stack assumes you do not already have PostgreSQL and Redis available, so it bundles PostgreSQL, Redis, FFmpeg, and the application for a one-command start.
-
Create a
.envfilecp .env.example .env -
Set your media path
Edit
.envand set:MEDIA_ROOT=/path/to/your/mediaMEDIA_ROOTis the one value most users need to change. You can also overrideSILO_DATA_ROOTif you do not want bind mounts under/opt/silo, and change ports if the defaults conflict with something else on the host. -
Start the default integrated stack
docker compose up -dThis starts PostgreSQL, Redis, and the integrated Silo server. The app is available at
http://localhost:8090. Jellyfin-compatible app support is disabled until an administrator enables it in onboarding or admin settings.If you already have PostgreSQL and Redis available, omit those bundled service examples from compose and point Silo at your existing
DATABASE_URLandREDIS_URLinstead.Optional NVIDIA/NVENC
GPU support is kept out of the default compose file so hosts without NVIDIA drivers work unchanged.
Install the NVIDIA Container Toolkit and use a Docker Compose version with GPU reservation support before enabling this override.
Use the optional override file when you want NVENC:
docker compose -f docker-compose.yml -f docker-compose.nvidia.yml up -dIf you want this controlled from
.env, setCOMPOSE_FILE:COMPOSE_FILE=docker-compose.yml:docker-compose.nvidia.yml NVIDIA_GPU_COUNT=1Windows uses
;instead of:between compose files.Then
docker compose up -dwill include the NVIDIA override automatically. -
Configure through the admin UI
Add libraries, users, metadata providers, and playback settings from the web interface.
Bind Mount Layout
The deploy-oriented compose files use host folder mappings rather than Docker-managed volumes.
By default, data is stored under /opt/silo:
/opt/silo/postgres/opt/silo/redis/opt/silo/transcode/opt/silo/catalog-seeds
Media is mounted into the container at /mnt/media from the host path you set in MEDIA_ROOT.
Optional Profiles
The main compose file is integrated-first. These profiles exist for operators testing distributed mode or mirroring a split deployment shape. Most single-host installs should stay on the default integrated service, because it already includes proxying and transcoding.
| Profile | Command | Description |
|---|---|---|
| default | docker compose up -d |
Integrated server plus bundled PostgreSQL and Redis |
proxy |
docker compose --profile proxy up -d |
Start a standalone proxy service for distributed-mode testing |
transcode |
docker compose --profile transcode up -d |
Start a standalone transcode service for distributed-mode testing |
You can enable both optional examples together:
docker compose --profile proxy --profile transcode up -d
If you are splitting workers across multiple hosts, use the separate remote worker example instead of trying to stretch the main compose file across machines.
Advanced Remote Node Example
For a dedicated remote transcode worker, use docker-compose.remote-transcode.yml. That file is intended for a separate worker host that connects back to an existing Silo deployment using shared PostgreSQL and Redis.
Deployment Notes
The default compose stack intentionally bundles PostgreSQL and Redis for ease of setup and assumes a fresh install without those services already available. If you already operate PostgreSQL and Redis, omit those examples from compose and point Silo at your existing infrastructure instead. For serious installs, PostgreSQL is better on a separate VM or a managed service so upgrades, tuning, and backups are isolated from the app host. Redis can stay local for many installs, but externalizing it is also reasonable if you already operate shared infrastructure.
Silo is externally stateful by default rather than fully stateless. Durable application state lives in PostgreSQL. Redis only stores coordination and cache-style data. Silo still writes transient transcode output locally under /tmp/silo-transcode. If you switch userdb.backend=sqlite, Silo also becomes locally stateful at /var/lib/silo/userdb.
Migrating an existing Continuum Docker install should be done with the preflight helper and cutover guide in docs/continuum-to-silo-docker-migration.md.
Configuration
Silo requires only a DATABASE_URL when running from source or against external infrastructure. In the default Docker Compose path, the stack wires the database and Redis URLs for you. All other settings — libraries, metadata providers, transcoding, users — are managed through the admin UI after first launch.
Server Modes
| Mode | Description |
|---|---|
integrated |
Full server: API + frontend + scanner + transcode (default) |
api |
API server only, no local transcoding |
proxy |
Stream proxy node that connects to the shared deployment database and Redis |
transcode |
HLS transcode worker node that connects to the shared deployment database and Redis |
PostgreSQL Auto-Tuning
The default Docker Compose stack does not require a checked-in postgresql.conf.
It enables Silo's pgtune-style OLTP tuning
by default:
POSTGRES_TUNE: auto
When enabled, Silo connects with DATABASE_URL and applies recommendations with
ALTER SYSTEM, which writes to PostgreSQL's postgresql.auto.conf inside the
database data directory. Reloadable settings are applied immediately with
pg_reload_conf(). Settings that PostgreSQL marks as restart-only are written
too, and Silo logs the setting names so you can restart PostgreSQL once:
docker compose restart postgres
The default Compose database user has the required PostgreSQL permissions. If
you use an external PostgreSQL server, make sure the configured DATABASE_URL
user can run ALTER SYSTEM, or set POSTGRES_TUNE=off and manage
PostgreSQL yourself.
For POSTGRES_TUNE_MEMORY=auto, Silo uses the first trustworthy memory source:
a finite Docker cgroup limit, the read-only /host/proc/meminfo mount supplied
by the bundled Compose file, then /proc/meminfo with container safety guards.
Auto-detected memory is treated as a PostgreSQL budget, defaulting to 75% of
detected RAM so Silo, Redis, plugins, transcodes, and the OS retain headroom.
POSTGRES_TUNE_DB_SIZE=auto queries pg_database_size(current_database()) and
classifies the workload by comparing the database size to that memory budget.
Optional tuning overrides:
| Variable | Default | Description |
|---|---|---|
POSTGRES_TUNE_PROFILE |
oltp |
Tuning profile. Only oltp is currently supported. |
POSTGRES_TUNE_MEMORY |
auto |
Server/container RAM, such as 8GB or 32GB; explicit values are used as-is. |
POSTGRES_TUNE_MEMORY_BUDGET_PERCENT |
75 |
Percent of auto-detected RAM used for PostgreSQL recommendations. |
POSTGRES_TUNE_CPUS |
auto |
CPU count used for worker recommendations. |
POSTGRES_TUNE_STORAGE |
ssd |
One of hdd, ssd, san, or nvme. |
POSTGRES_TUNE_DB_SIZE |
auto |
Use less_ram when the database comfortably fits in RAM, mid_ram, or greater_ram for very large databases. |
POSTGRES_TUNE_CONNECTIONS |
100 |
PostgreSQL max_connections; automatically raised if Silo's app pool is configured higher. |
POSTGRES_SHM_SIZE |
8gb |
Docker /dev/shm size for the bundled PostgreSQL container. |
Advanced operators can still supply their own PostgreSQL configuration or
override these env vars. Set POSTGRES_TUNE=off when you do not want Silo to
change PostgreSQL server settings. Settings already written with ALTER SYSTEM
remain in postgresql.auto.conf; reset those PostgreSQL parameters if you later
move fully to a custom postgresql.conf.
Build from Source
If you prefer running Silo without Docker:
-
Install prerequisites: Go 1.24+, Bun 1.0+, PostgreSQL 18+, and FFmpeg.
-
Start PostgreSQL and Redis (skip if you already have them running)
docker compose up -d postgres redisThe main compose file still expects
MEDIA_ROOTto be set even if you only want the bundled PostgreSQL and Redis services, so set that in.envfirst. -
Configure the database connection
cp .env.example .envEdit
.envand setDATABASE_URLto point to your PostgreSQL instance. -
Build and run
make build ./siloThe server starts at
http://localhost:8080by default. All other settings are configured through the admin UI.
Reporting Issues
If you are reporting a bug, install problem, or performance issue, start with the admin workflow and reproduction steps, not Claude/Codex analysis.
Please include:
- What you were trying to do
- Exact steps you took
- What you expected to happen
- What actually happened
- What exact action is slow or broken (
save,scan,browse,import,playback, etc.) - Whether it happens every time or only sometimes
- The library, media type, filter, setting, or value involved
- Version, branch, commit, and deployment details if you know them
- Screenshots, recordings, or log snippets if relevant
If you used Claude/Codex for debugging, put that under Technical notes at the end. Suspected files, SQL output, stack traces, and root-cause theories can be helpful, but only after the workflow and repro steps are clear.
Use this template:
Goal:
Steps:
Expected:
Actual:
What is slow/broken:
Scope:
Version/branch:
Deployment:
Technical notes:
Contributing & Development
Silo is open source and contributions are welcome. See DEVELOPMENT.md for building from source in a dev workflow, running tests, database migrations, and project layout, and CONTRIBUTING.md for contribution expectations, merge request guidance, and the policy for AI-assisted submissions.
Supporting Silo
Silo is an open-source hobby project, developed in spare time and funded out of pocket. If you'd like to support development, you can sponsor via GitHub Sponsors.
Donations go directly toward the costs of building and running the project:
- AI development tooling subscriptions (Claude, Codex) used to build and maintain Silo
- Push notification relay infrastructure
- Future development costs
Sponsoring is entirely optional — Silo is and will remain free and open source. Bug reports, contributions, and feedback are just as valuable.
License & Trademarks
Silo's source code is licensed under the GNU Affero General Public License
v3.0 or later (AGPL-3.0-or-later) — see LICENSE.
The Silo name, logo, and wordmark are trademarks of Silo Media L.L.C. and are not covered by the AGPL. You're free to fork and redistribute the code, but forks and redistributions must not use the Silo brand as their identity and must remove or replace the brand assets. Publishing a Silo-branded app to an app store requires written permission. See TRADEMARK.md for what's permitted — including referential use like "compatible with Silo."