> For the complete documentation index, see [llms.txt](https://docs.eyepop.ai/developer-documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.eyepop.ai/developer-documentation/platform/sources-and-options.md).

# Sources and Options

Every way to hand media to a Pop, and the options that shape how it is processed

A [Pop](/developer-documentation/platform/pop.md) describes *what* to run. A **source** is *what to run it on*: one image, one video, one live stream handed to a running session. Every inference is a source submitted to a session, whatever language you call from.

Each source carries its own **options** — a frame rate to throttle to, a region to crop, motion gating, per-component overrides. Options are set per source, so a single session can take a still at full resolution and a camera feed at one frame per second.

### Upload or fetch

There are two ways the media reaches the worker, and the choice is usually made for you by where the media already is.

|                     | **Upload**                                                                | **Fetch**                                                        |
| ------------------- | ------------------------------------------------------------------------- | ---------------------------------------------------------------- |
| Who moves the bytes | your application                                                          | the worker                                                       |
| Can reach           | anything your process can read — local disk, memory, a browser `File`     | anything the worker can reach over the network                   |
| Best for            | files on the machine running your code, generated frames, browser uploads | camera streams, object storage, CDN-hosted media, anything large |

Fetching keeps the media off your egress path entirely: you send a URL, the worker opens it. Uploading is the only option when the media is not reachable from EyePop's network — which is also the case for cameras on a private LAN, where [Private Cameras](/developer-documentation/deploying/cloud/private-cameras.md) covers the connectivity.

### Supported sources

| Source                                        | How it arrives  | Python                                                   | Node                                                |
| --------------------------------------------- | --------------- | -------------------------------------------------------- | --------------------------------------------------- |
| Local file                                    | upload          | `upload(path)`                                           | `process({ source: { path } })`                     |
| Binary stream                                 | upload          | `upload_stream(stream, mime_type)`                       | `process({ source: { stream, mimeType } })`         |
| Browser `File`                                | upload          | —                                                        | `process({ source: { file } })`                     |
| HTTP(S) URL                                   | fetch           | `load_from(url)`                                         | `process({ source: { url } })`                      |
| RTSP / RTSPS camera                           | fetch           | `load_from(url)`                                         | `process({ source: { url } })`                      |
| RTMP stream                                   | fetch           | `load_from(url)`                                         | `process({ source: { url } })`                      |
| Browser webcam or screen (WebRTC)             | push            | —                                                        | `process({ source: { mediaStream } })`              |
| Dataset asset                                 | fetch           | `load_asset(asset_uuid)`                                 | `process({ source: { assetUuid } })`                |
| Image group (2–16 images, one inference unit) | upload or fetch | `upload_group`, `upload_stream_group`, `load_from_group` | `uploadGroup`, `uploadStreamGroup`, `loadFromGroup` |

Each is shown with runnable code in [Source Types](/developer-documentation/platform/sources-and-options/sources.md), and the image formats, video codecs, and containers behind them are listed in [Supported Formats](/developer-documentation/platform/sources-and-options/formats.md).

### What comes back

A source produces a stream of predictions, delivered as they are produced rather than at the end:

* **an image** — one prediction
* **a video or a live stream** — one prediction per processed frame, until the source ends. A live stream ends when you cancel it
* **an image group** — one prediction for the whole group, because a group is a single inference unit

Sources submitted to one session are **queued and processed in order** — submitting a second does not wait for the first to finish, but the worker runs them one at a time. To process several genuinely in parallel, use separate sessions.

Queueing is what the SDKs ask for, not the only thing the platform can do: the behaviour is chosen per source, and a source can also preempt whatever is running or be rejected outright. One source type takes that other path — a browser [`MediaStream`](/developer-documentation/platform/sources-and-options/sources.md#live-from-a-browser) **preempts** the running source, because live media that waits its turn is no longer live.

### Next steps

* [Source Types](/developer-documentation/platform/sources-and-options/sources.md) — every source, with Python and Node examples
* [Supported Formats](/developer-documentation/platform/sources-and-options/formats.md) — the image formats, video codecs, and containers a Pop can decode
* [Source Options](/developer-documentation/platform/sources-and-options/options.md) — frame rate, region of interest, motion gating, and component parameters
* [Pop Defaults](/developer-documentation/platform/sources-and-options/pop-defaults.md) — set options once on the Pop instead of on every source