nips/44.md

NIP-44
======

Video Events
---------------

`draft` `optional`

This specification defines video events representing a dedicated post of externally hosted content. These video events are _parameterized replaceable_ and deletable per [NIP-09](09.md).

Unlike a `kind 1` event with a video attached, Video Events are meant to contain all necessary metadata concerning the media and to be surfaced in media specific clients rather than general micro-blogging clients. The thought is for events of this kind to be referenced in a YouTube like nostr client where the video itself is at the center of the experience.

## Video Events

There are two types of video events represented by different kinds: horizontal and vertical video events. This is meant to allow clients to cater to each as the viewing experience for horizontal (landscape) videos is often different than that of vertical (portrait) videos (Stories, Reels, Shorts, etc).

#### Format

The format uses a parameterized replaceable event kind `34235` for horizontal videos and `34236` for vertical videos.

The `.content` of these events is optional and should be a summary of the video's contents.

The list of tags are as follows:
* `d` (required) universally unique identifier (UUID). Generated by the client creating the video event.
* `title` (required) title of the video
* `url` (required) a link to the video data
* `m` (optional) the MIME type of the video data in the `src` tag
* `summary` (optional) summary/description of the video (same as content)
* `image` (optional) url of preview image with same dimensions
* `thumb` (optional) url of thumbnail with same aspect ratio
* `dim` (optional) size of file in pixels in the form <width>x<height>
* `text-track` (optional, repeated) link to WebVTT file for video, type of supplementary information (captions/subtitles/chapters/metadata), optional language code
* `content-warning` (optional) warning about content of NSFW video
* `alt` (optional) description for accessibility
* `t` (optional, repeated) hashtag to categorize video
* `p` (optional, repeated) 32-bytes hex pubkey of a participant in the video, optional recommended relay URL
* `r` (optional, repeated) references / links to web pages.

```json
{
  "id": <32-bytes lowercase hex-encoded SHA-256 of the the serialized event data>,
  "pubkey": <32-bytes lowercase hex-encoded public key of the event creator>,
  "created_at": <Unix timestamp in seconds>,
  "kind": 34235 | 34236,
  "content": "<summary of video>",
  "tags": [
    ["d", "<UUID>"],

    ["title", "<title of video>"],
    ["summary", "<summary of video>"],
    ["thumb", "<thumbnail image for video>"],
    ["image", "<preview image for video>"],
    ["alt", <description>],

    // Video Data
    ["url", "<url>"],
    ["m", "<MIME type>"],
    ["text-track", "<url>", "<text track type>", "<optional language>"],
    ["content-warning", "<reason>"],
    ["dim", <size of video in pixels>],

    // Participants
    ["p", "<32-bytes hex of a pubkey>", "<optional recommended relay URL>"],
    ["p", "<32-bytes hex of a pubkey>", "<optional recommended relay URL>"],

    // Hashtags
    ["t", "<tag>"],
    ["t", "<tag>"],

    // Reference links
    ["r", "<url>"],
    ["r", "<url>"]
  ]
}
```

## Video View

A video event view is a response to a video event to track a user's view or progress viewing the video.

### Format

The format uses a parameterized replaceable event kind `34237`.

The `.content` of these events is optional and could be a free-form note that acts like a bookmark for the user.

The list of tags are as follows:
* `a` (required) reference tag to kind `34235` or `34236` video event being viewed
* `d` (required) same as `a` reference tag value
* `viewed` (optional, repeated) timestamp of the user's start time in `HH:MM:SS.sss`, timestamp of the user's end time in `HH:MM:SS.sss` 


```json
{
  "id": <32-bytes lowercase hex-encoded SHA-256 of the the serialized event data>,
  "pubkey": <32-bytes lowercase hex-encoded public key of the event creator>,
  "created_at": <Unix timestamp in seconds>,
  "kind": 34237,
  "content": "<note>",
  "tags": [
    ["a", "<34235 | 34236>:<video event author pubkey>:<d-identifier of video event>", "<optional relay url>"],
    ["d", "<34235 | 34236>:<video event author pubkey>:<d-identifier of video event>"],
    ["viewed", <start>, <end>],
  ]
}
```