# Authorizing a Picture Frame

**URL:** <https://forum.decentraland.org/t/authorizing-a-picture-frame/16>\
**Category:** Design Document\
**Created:** [April 9, 2020, 3:18am UTC](https://forum.decentraland.org/t/authorizing-a-picture-frame/16 "2020-04-09T03:18:08Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![esteban](https://dub1.discourse-cdn.com/flex013/user_avatar/forum.decentraland.org/esteban/32/2_2.png) [@esteban](https://forum.decentraland.org/u/esteban)\
**Post date:** [April 9, 2020, 3:18am UTC](https://forum.decentraland.org/t/authorizing-a-picture-frame/16/1 "2020-04-09T03:18:08Z")

</div>

## What is a Picture Frame? What does it allow me to do?

A picture frame in Decentraland is a special way to display something on your scene, validating the ownership of the NFT is linked to the user that has deployed the scene ([see this document](https://forum.decentraland.org/t/a-recap-land-ownership-deployment-permissions/12) for information on who can deploy to a scene).

For example, I could have a gallery in my scene showcasing a collection of NFTs that make up a private collection, and host them for an auction or in permanent exposition like in a real world museum.

MakersPlace does this already with their website:

 ![A Creepy Rabbit Owned by Holodot https://makersplace.com/authenticity/0x2a46f2ffd99e19a89476e2f62270e0a35bbf0756/7224/](https://europe1.discourse-cdn.com/flex013/uploads/decentraland/original/1X/6d5058cd4c37e96887b858529f13d33ed60840cb.jpeg)

What is the key value proposition here?

NFT Art and Collectibles:

- Have verifiable and indisputable cryptographic ownership
- Can be traced through time, allowing you to know the history of the item
- May be traded with zero risk through a trust-free marketplace contract

## How can NFTs in a Contract become Picture Frames?

There’s a global registry for NFTs sitting on a blockchain contract owned by the Decentraland DAO. This contract ([mainnet](https://MISSING%20FEATURE), [ropsten,](https://MISSING%20FEATURE) [source code](https://MISSING%20FEATURE)) can be modified by an Aragon Vote.

This is its interface:

```auto
contract DARRegistry is Ownable {
  function registerDAR(darAddress, darURL) public;
  function getDARUrl(darAddress) public;
  function unregisterDAR(darAddress) public;
}

```

## Pinging the DAR

Currently, all picture frames are being served from `schema.decentraland.org` :

- CryptoKitties
- HyperDragons
- Axie Infinity
- … complete list on [https://github.com/decentraland/nft-schema-api/blob/master/data/dar.json](https://github.com/decentraland/nft-schema-api/blob/master/data/dar.json)

Hitting the API should give:

- [https://schema.decentraland.org/dar/0x7fdcd2a1e52f10c28cb7732f46393e297ecadda1/](https://schema.decentraland.org/dar/0x7fdcd2a1e52f10c28cb7732f46393e297ecadda1/asset/123)
  - Alias: [https://schema.decentraland.org/dar/hyper-dragons/](https://schema.decentraland.org/dar/0x7fdcd2a1e52f10c28cb7732f46393e297ecadda1/asset/123)
  - Description of the collection

- [https://schema.decentraland.org/dar/0x7fdcd2a1e52f10c28cb7732f46393e297ecadda1/asset/123](https://schema.decentraland.org/dar/0x7fdcd2a1e52f10c28cb7732f46393e297ecadda1/asset/123)
  - Description of asset #123 of the collection
  - Alias: [https://schema.decentraland.org/dar/hyper-dragons/asset/123](https://schema.decentraland.org/dar/0x7fdcd2a1e52f10c28cb7732f46393e297ecadda1/asset/123)

- [https://schema.decentraland.org/dar/axie-infinity/address/0x3945476e477de76d53b4833a46c806ef3d72b21e](https://schema.decentraland.org/dar/axie-infinity/address/0x3945476e477de76d53b4833a46c806ef3d72b21e)[https://schema.decentraland.org/dar/axie-infinity/address/0x3945476e477de76d53b4833a46c806ef3d72b21e](https://schema.decentraland.org/dar/axie-infinity/address/0x3945476e477de76d53b4833a46c806ef3d72b21e)
  - All assets owned by address 0x394…21e

Example:

### DAR Example

```auto
(async function() { return await (await fetch(
  'https://schema.decentraland.org/dar/hyper-dragons/'
)).json()})()

```

### NFT example

```auto
(async function() { const d = await (await fetch(
  'https://schema.decentraland.org/dar/hyper-dragons/asset/123'
)).json()
  d.files = d.files.filter(_ => _.role && _.role.startsWith('dcl-picture-frame-image'))
  return d
})()

```

# The Vote of a New Picture Frame

## 1. Definition of the DAR

Before proposing a vote on the DAR, one must make sure the endpoint being proposed as a DAR is available. It’s recommended to deploy it under some High Availability schema, to be accessible across the world with low latency.

- The submitted endpoint should be the main endpoint for the collection. For example,
  - [https://schema.decentraland.org/dar/axie-infinity](https://schema.decentraland.org/dar/axie-infinity/address/0x3945476e477de76d53b4833a46c806ef3d72b21e)
  - A trailing slash at the end of the URL is discouraged
  - The following fields are mandatory:
    - `common_name` must coincide with the last part of the URL (`axie-infinity` in this example)
    - `name` a human-readable name, `Axie Infinity` in this example
    - `contract_uri` the URI for the token. Only `ethereum` is currently supported as a blockchian. Example: `ethereum://0xf5b0a3efb8e8e4c201e2a935f110eaaf3ffecb8d`
    - `description` a human-readable description of the token
    - `schema_url` the same URL as submitted to the DAO ([`https://schema.decentraland.org/dar/axie-infinity`](https://schema.decentraland.org/dar/axie-infinity/address/0x3945476e477de76d53b4833a46c806ef3d72b21e) in this example)
      - `image_url` a PNG or ICO image to recognize this token. `https://axieinfinity.com/team/favicon.ico` in this example.

## 2. Required fields per each NFT

- `description`
- `owner`
- `name`
- `registry`
- `token_id`
- `uri`
- `files`
  - `name`
  - `url`
  - `role`
  - `roles`

## 3. Automatically verifying every NFT

```auto
async function fetchNFT(collection, id) {
  return await (await fetch(
    `https://schema.decentraland.org/dar/${collection}/asset/${id}`
  )).json()
}
async function verifyNFT(nft, validationError) {
  if (validationError(nft)) {
    return validationError(nft)
  }
}
const needsField = field => _ => _[field] === undefined ? `missing field ${field}` : undefined
const validations = [
  needsField('name'),
  needsField('description'),
  needsField('owner'),
  needsField('registry'),
  needsField('uri'),
  needsField('token_id'),
  _ => _.files.filter($ => $.role === 'dcl-picture-frame-image')[0] ? undefined : 'no file with "dcl-picture-frame" found'
]
async function main(collection, id) {
  const nft = await fetchNFT(collection, id)
  const errors = validations.map($ => $(nft)).filter(_ => _)
  if (errors.length) {
    return `error: ${errors.join(',')}`
  }
  return `all ok`
}
main('hyper-dragons', 123)

```

## 4. Voting

When voting, the UI should run a number of these tests – ideally all the NFTs; but random sampling might be applied. The images should also be checked that they are of the correct format and size (512x512 pixels).

# Interaction in the world

## Verifiable Frame

Picture frames in the world have a glowing border that makes it distinguishable from any single image. It’s unfortunate that this effect impacts on the image being verified; but it is necessary to avoid one picture in front of an actual image.

## Pop up display

Upon clicking; a display screen should be shown with more information about the picture. See the image above:

- Name of the collection
- Name of the NFT
- Description of the NFT
- ID of the NFT
- Information about the issuance of the item
- Link to the collection on the marketplace
- Author information
- Owner information

## Connection with the Marketplace

In case the NFT is for sale; the price should be shown on the Pop up display.

## Author information

In future versions; the NFT associated with the picture might have information regarding who was the original creator of the image (the artist that created the collectible).  
In this case; and if the artist has created a profile, they should have their name and profile associated with the picture frame.