Technical media metadata
Technical media metadata describes the encoded resource, tracks and presentation properties recovered by parsing, probing or analysis.
Technical metadata characterizes a particular media resource and its streams. It can include container/codec identification, dimensions, duration, track layout and applicable presentation signaling.
A provider's synopsis cannot establish those properties of the local file. They come from that resource's structure or analysis.
File, stream and presentation have different properties
| Scope | Example properties |
|---|---|
| File/container | Packaging, size, contained streams |
| Video stream | Codec/profile, sample dimensions, timing and colour signaling |
| Audio stream | Codec, sample rate, channel description |
| Subtitle stream | Coding, language/role description, applicable timing |
| Image | Sample grid, orientation and colour interpretation |
Some information is declared in headers, some inferred, and some measured by reading more of the resource. A short probe and a full analysis need not establish the same level of detail.
For example, a declared language can be readable metadata without proof that every spoken passage uses that language. A valid codec identifier also does not establish that the entire bitstream is undamaged.
Average file rate includes everything in the file
Take an invented resource of 210,000,000 bytes lasting 600 seconds:
210000000 × 8 / 600 = 2,800,000 bits/s, or 2.8 Mb/s.
That whole-file average includes its audio, subtitles, packaging and other stored material. It should not automatically be copied into a field describing the video's average bitrate.
Peak delivery demand has another relationship to time. A short high-rate section can matter for streaming even when the full-file average is modest. Bitrate develops that distinction.
Replacing the resource can invalidate old observations
A new encode of the same film can have another resolution, track set or timeline. Retaining the film's descriptive identity may be appropriate; retaining old stream details can be wrong.
In Emby, compare the actual selected media source with the technical data exposed for it. If a playback description reports a missing track or an old resolution, establish whether it refers to the updated file or another version before editing unrelated descriptive fields.
Technical renewal and provider refresh answer different questions. The first recovers the resource's properties; the second seeks descriptive information about the associated work.