Preview and Processing
Preview and processing turn original files into browser-viewable, openable, or streamable results. This area does not change file ownership, but it depends on storage reads, background tasks, external tools, and WOPI services.
Capability Boundaries
| Capability | Notes | Related docs |
|---|---|---|
| Thumbnails | Thumbnail generation, cache, and background tasks for supported MIME types | System Settings, User Manual |
| Image preview | Browser original rendering, backend-generated medium previews, fullscreen viewing, zoom, pan, rotation, and previous/next navigation | User Manual, System Settings |
| Media metadata | Audio/video metadata from local tools or storage-native processing | Tencent COS |
| Archive preview | Read-only listing of supported archive paths, names, sizes, and modified times; disabled by default | Online Preview and WOPI, System Settings |
| WOPI | OnlyOffice / Collabora open and save flows | Online Preview and WOPI, File Editing |
| Browser editing | Text-like file editing, saves, version records | File Editing |
| Share streaming | Short-lived audio/video playback session on share pages | Sharing and Public Access, System Settings |
Backend Modules
| Module | Owns |
|---|---|
thumbnail, task::thumbnail | Thumbnail and image-preview cache and task dispatch |
media::processing | VIPS / FFmpeg / FFprobe processor resolution |
media::metadata | Audio/video metadata parsing |
files::archive::core, files::archive::preview | Archive scanning, path validation, read-only preview |
preview::apps, preview::wopi | Preview apps, WOPI discovery, locks, proof, sessions |
share::ticket, share::stream | Share streaming tickets and short sessions |
Configuration Entry Points
| Entry point | Purpose |
|---|---|
Admin -> System Settings -> File Processing | Thumbnails, image preview strategy, media processors, archive preview |
Admin -> System Settings -> Site Configuration -> Preview Apps | WOPI discovery and open methods |
Admin -> System Settings -> Runtime | Share streaming session TTL and runtime limits |
| Storage policy editor | Storage-native processing switches such as Tencent COS |
Troubleshooting Direction
- WOPI does not open: confirm public site URL, WOPI callback reachability, and enabled file extensions.
- Thumbnails or image previews do not generate: check MIME support, failed background tasks, processor availability, and whether the source file exceeds the size limit.
- Archive preview fails: check global switch, file size, supported format, and archive path safety.
- Share-page media playback stops: check share streaming session TTL and reverse proxy streaming behavior.