Image Description¶
The Image type is defined in ActivityStreams Vocabulary.
In this support table, we only consider how the image description, commonly called AltText is handled. Image descriptions are important from an accessibility standpoint, see WCAG 2.2. Text Alternatives.
It seems that certain implementations, e.g. firefish, store the image description on a per image URL basis and not for every instance of an image reference.
Examples¶
Example 1¶
activity
{
"@context": [
"https://www.w3.org/ns/activitystreams",
{
"Hashtag": "as:Hashtag",
"sensitive": "as:sensitive"
}
],
"type": "Create",
"actor": "http://pasture-one-actor/actor",
"to": [
"http://hollo/@john",
"https://www.w3.org/ns/activitystreams#Public"
],
"id": "http://pasture-one-actor/actor/Y_47pmX9AsM",
"published": "2024-10-30T15:56:47Z",
"object": {
"type": "Note",
"attributedTo": "http://pasture-one-actor/actor",
"to": [
"https://www.w3.org/ns/activitystreams#Public",
"http://hollo/@john"
],
"id": "http://pasture-one-actor/actor/T2HjnnySq6k",
"published": "2024-10-30T15:56:47Z",
"content": "no description",
"attachment": {
"type": "Document",
"url": "http://pasture-one-actor/images/100.png"
},
"tag": [
{
"type": "Mention",
"href": "http://gotosocial/users/cookie"
}
]
}
}
hollo
{
"id": "0192de24-ce18-789f-a78c-bb531c263127",
"created_at": "2024-10-30T15:56:47.000Z",
"in_reply_to_id": null,
"sensitive": false,
"spoiler_text": "",
"visibility": "public",
"language": null,
"uri": "http://pasture-one-actor/actor/T2HjnnySq6k",
"url": null,
"replies_count": 0,
"reblogs_count": 0,
"favourites_count": 0,
"favourited": false,
"reblogged": false,
"muted": false,
"bookmarked": false,
"pinned": false,
"content": "no description",
"reblog": null,
"quote_id": null,
"quote": null,
"application": null,
"account": {
"id": "0192de24-1e6d-712c-9efb-1801e3b352b1",
"username": "actor",
"acct": "actor@pasture-one-actor",
"display_name": "Test Actor",
"locked": false,
"bot": false,
"created_at": "2024-10-30T15:56:01.966Z",
"note": "",
"url": "http://pasture-one-actor/actor",
"avatar": "http://hollo/image/avatars/original/missing.png",
"avatar_static": "http://hollo/image/avatars/original/missing.png",
"header": "http://hollo/image/headers/original/missing.png",
"header_static": "http://hollo/image/headers/original/missing.png",
"followers_count": 0,
"following_count": 0,
"statuses_count": 0,
"moved": null,
"last_status_at": null,
"emojis": [],
"fields": []
},
"media_attachments": [
{
"id": "0192de24-d245-7f18-946f-abc146a08a6c",
"type": "image",
"url": "http://pasture-one-actor/images/100.png",
"preview_url": "http://pasture-one-actor/images/100.png",
"remote_url": null,
"text_url": null,
"meta": {
"original": {
"width": 512,
"height": 512,
"size": "512x512",
"aspect": 1
},
"small": {
"width": 512,
"height": 512,
"size": "512x512",
"aspect": 1
},
"focus": {
"x": 0,
"y": 0
}
},
"description": null,
"blurhash": null
}
],
"mentions": [],
"tags": [],
"card": null,
"emojis": [],
"emoji_reactions": [],
"poll": null,
"filtered": null
}
sharkey
{
"id": "9zzma02wte6p000y",
"uri": "http://pasture-one-actor/actor/RRbqQibtmcY",
"url": "http://pasture-one-actor/actor/RRbqQibtmcY",
"account": {
"id": "9zzm83xete6p0002",
"username": "actor",
"acct": "actor@pasture-one-actor",
"fqn": "actor@pasture-one-actor",
"display_name": "Test Actor",
"locked": false,
"created_at": "2024-10-30T15:48:24.674Z",
"followers_count": 0,
"following_count": 0,
"statuses_count": 26,
"note": "",
"url": "http://pasture-one-actor/actor",
"uri": "http://pasture-one-actor/actor",
"avatar": "https://dev.joinsharkey.org/static-assets/avatar.png",
"avatar_static": "https://dev.joinsharkey.org/static-assets/avatar.png",
"header": "https://dev.joinsharkey.org/static-assets/transparent.png",
"header_static": "https://dev.joinsharkey.org/static-assets/transparent.png",
"emojis": [],
"moved": null,
"fields": [],
"bot": false,
"discoverable": true
},
"in_reply_to_id": null,
"in_reply_to_account_id": null,
"reblog": null,
"content": "<p><span>no description</span></p>",
"content_type": "text/x.misskeymarkdown",
"text": "no description",
"created_at": "2024-10-30T15:49:53.000Z",
"emojis": [],
"replies_count": 0,
"reblogs_count": 0,
"favourites_count": 0,
"reblogged": false,
"favourited": false,
"muted": false,
"sensitive": false,
"spoiler_text": "",
"visibility": "public",
"media_attachments": [
{
"id": "9zzma0dfte6p000x",
"type": "image",
"url": "http://pasture-one-actor/images/100.png",
"remote_url": "http://pasture-one-actor/images/100.png",
"preview_url": "http://pasture-one-actor/images/100.png",
"text_url": "http://pasture-one-actor/images/100.png",
"meta": {
"width": 40,
"height": 40
},
"description": null,
"blurhash": "e00dK-kFfQkFfQkFfRfQfRfQfQfQfQfQfQkFfRfQfRfQfQfQfQfQfQ"
}
],
"mentions": [],
"tags": [],
"card": null,
"poll": null,
"application": null,
"language": null,
"pinned": false,
"reactions": [],
"emoji_reactions": [],
"bookmarked": false,
"quote": null,
"edited_at": null
}
Example 2¶
activity
{
"@context": [
"https://www.w3.org/ns/activitystreams",
{
"Hashtag": "as:Hashtag",
"sensitive": "as:sensitive"
}
],
"type": "Create",
"actor": "http://pasture-one-actor/actor",
"to": [
"http://hollo/@john",
"https://www.w3.org/ns/activitystreams#Public"
],
"id": "http://pasture-one-actor/actor/xrM5BF7R4Cw",
"published": "2024-10-30T15:56:48Z",
"object": {
"type": "Note",
"attributedTo": "http://pasture-one-actor/actor",
"to": [
"https://www.w3.org/ns/activitystreams#Public",
"http://hollo/@john"
],
"id": "http://pasture-one-actor/actor/Eh9tgDLiptc",
"published": "2024-10-30T15:56:48Z",
"content": "text",
"attachment": {
"type": "Document",
"url": "http://pasture-one-actor/images/100.png",
"name": "name",
"summary": "summary",
"content": "content"
},
"tag": [
{
"type": "Mention",
"href": "http://gotosocial/users/cookie"
}
]
}
}
hollo
{
"id": "0192de24-d200-75c4-ba1b-18ebb91edf3d",
"created_at": "2024-10-30T15:56:48.000Z",
"in_reply_to_id": null,
"sensitive": false,
"spoiler_text": "",
"visibility": "public",
"language": null,
"uri": "http://pasture-one-actor/actor/Eh9tgDLiptc",
"url": null,
"replies_count": 0,
"reblogs_count": 0,
"favourites_count": 0,
"favourited": false,
"reblogged": false,
"muted": false,
"bookmarked": false,
"pinned": false,
"content": "text",
"reblog": null,
"quote_id": null,
"quote": null,
"application": null,
"account": {
"id": "0192de24-1e6d-712c-9efb-1801e3b352b1",
"username": "actor",
"acct": "actor@pasture-one-actor",
"display_name": "Test Actor",
"locked": false,
"bot": false,
"created_at": "2024-10-30T15:56:01.966Z",
"note": "",
"url": "http://pasture-one-actor/actor",
"avatar": "http://hollo/image/avatars/original/missing.png",
"avatar_static": "http://hollo/image/avatars/original/missing.png",
"header": "http://hollo/image/headers/original/missing.png",
"header_static": "http://hollo/image/headers/original/missing.png",
"followers_count": 0,
"following_count": 0,
"statuses_count": 0,
"moved": null,
"last_status_at": null,
"emojis": [],
"fields": []
},
"media_attachments": [
{
"id": "0192de24-d5ca-7290-998d-b3402d2d4837",
"type": "image",
"url": "http://pasture-one-actor/images/100.png",
"preview_url": "http://pasture-one-actor/images/100.png",
"remote_url": null,
"text_url": null,
"meta": {
"original": {
"width": 512,
"height": 512,
"size": "512x512",
"aspect": 1
},
"small": {
"width": 512,
"height": 512,
"size": "512x512",
"aspect": 1
},
"focus": {
"x": 0,
"y": 0
}
},
"description": "summary",
"blurhash": null
}
],
"mentions": [],
"tags": [],
"card": null,
"emojis": [],
"emoji_reactions": [],
"poll": null,
"filtered": null
}
sharkey
{
"id": "9zzma0uote6p0010",
"uri": "http://pasture-one-actor/actor/TWBqixHWMwQ",
"url": "http://pasture-one-actor/actor/TWBqixHWMwQ",
"account": {
"id": "9zzm83xete6p0002",
"username": "actor",
"acct": "actor@pasture-one-actor",
"fqn": "actor@pasture-one-actor",
"display_name": "Test Actor",
"locked": false,
"created_at": "2024-10-30T15:48:24.674Z",
"followers_count": 0,
"following_count": 0,
"statuses_count": 27,
"note": "",
"url": "http://pasture-one-actor/actor",
"uri": "http://pasture-one-actor/actor",
"avatar": "https://dev.joinsharkey.org/static-assets/avatar.png",
"avatar_static": "https://dev.joinsharkey.org/static-assets/avatar.png",
"header": "https://dev.joinsharkey.org/static-assets/transparent.png",
"header_static": "https://dev.joinsharkey.org/static-assets/transparent.png",
"emojis": [],
"moved": null,
"fields": [],
"bot": false,
"discoverable": true
},
"in_reply_to_id": null,
"in_reply_to_account_id": null,
"reblog": null,
"content": "<p><span>text</span></p>",
"content_type": "text/x.misskeymarkdown",
"text": "text",
"created_at": "2024-10-30T15:49:54.000Z",
"emojis": [],
"replies_count": 0,
"reblogs_count": 0,
"favourites_count": 0,
"reblogged": false,
"favourited": false,
"muted": false,
"sensitive": false,
"spoiler_text": "",
"visibility": "public",
"media_attachments": [
{
"id": "9zzma0zvte6p000z",
"type": "image",
"url": "http://pasture-one-actor/images/100.png",
"remote_url": "http://pasture-one-actor/images/100.png",
"preview_url": "http://pasture-one-actor/images/100.png",
"text_url": "http://pasture-one-actor/images/100.png",
"meta": {
"width": 40,
"height": 40
},
"description": "name",
"blurhash": "e2M@Ls~kfQ~kfQ~kj@fQj@fQfQfQfQfQfQ~kj@fQj@fQfQfQfQfQfQ"
}
],
"mentions": [],
"tags": [],
"card": null,
"poll": null,
"application": null,
"language": null,
"pinned": false,
"reactions": [],
"emoji_reactions": [],
"bookmarked": false,
"quote": null,
"edited_at": null
}
Example 3¶
activity
{
"@context": [
"https://www.w3.org/ns/activitystreams",
{
"Hashtag": "as:Hashtag",
"sensitive": "as:sensitive"
}
],
"type": "Create",
"actor": "http://pasture-one-actor/actor",
"to": [
"http://hollo/@john",
"https://www.w3.org/ns/activitystreams#Public"
],
"id": "http://pasture-one-actor/actor/yOUV8HhR7iM",
"published": "2024-10-30T15:56:49Z",
"object": {
"type": "Note",
"attributedTo": "http://pasture-one-actor/actor",
"to": [
"https://www.w3.org/ns/activitystreams#Public",
"http://hollo/@john"
],
"id": "http://pasture-one-actor/actor/Y3Hj6lzo2Xk",
"published": "2024-10-30T15:56:49Z",
"content": "text",
"attachment": [
{
"type": "Document",
"url": "http://pasture-one-actor/assets/FediverseLogo.png",
"name": "name",
"imageType": "image/jpeg"
}
],
"tag": [
{
"type": "Mention",
"href": "http://gotosocial/users/cookie"
}
]
}
}
hollo
{
"id": "0192de24-d5e8-751d-8fae-62e839adbf73",
"created_at": "2024-10-30T15:56:49.000Z",
"in_reply_to_id": null,
"sensitive": false,
"spoiler_text": "",
"visibility": "public",
"language": null,
"uri": "http://pasture-one-actor/actor/Y3Hj6lzo2Xk",
"url": null,
"replies_count": 0,
"reblogs_count": 0,
"favourites_count": 0,
"favourited": false,
"reblogged": false,
"muted": false,
"bookmarked": false,
"pinned": false,
"content": "text",
"reblog": null,
"quote_id": null,
"quote": null,
"application": null,
"account": {
"id": "0192de24-1e6d-712c-9efb-1801e3b352b1",
"username": "actor",
"acct": "actor@pasture-one-actor",
"display_name": "Test Actor",
"locked": false,
"bot": false,
"created_at": "2024-10-30T15:56:01.966Z",
"note": "",
"url": "http://pasture-one-actor/actor",
"avatar": "http://hollo/image/avatars/original/missing.png",
"avatar_static": "http://hollo/image/avatars/original/missing.png",
"header": "http://hollo/image/headers/original/missing.png",
"header_static": "http://hollo/image/headers/original/missing.png",
"followers_count": 0,
"following_count": 0,
"statuses_count": 0,
"moved": null,
"last_status_at": null,
"emojis": [],
"fields": []
},
"media_attachments": [
{
"id": "0192de24-d8d8-79ec-97ff-6e31be7e40b2",
"type": "image",
"url": "http://pasture-one-actor/assets/FediverseLogo.png",
"preview_url": "http://pasture-one-actor/assets/FediverseLogo.png",
"remote_url": null,
"text_url": null,
"meta": {
"original": {
"width": 512,
"height": 512,
"size": "512x512",
"aspect": 1
},
"small": {
"width": 512,
"height": 512,
"size": "512x512",
"aspect": 1
},
"focus": {
"x": 0,
"y": 0
}
},
"description": "name",
"blurhash": null
}
],
"mentions": [],
"tags": [],
"card": null,
"emojis": [],
"emoji_reactions": [],
"poll": null,
"filtered": null
}
sharkey
{
"id": "9zzma0uote6p0012",
"uri": "http://pasture-one-actor/actor/UFwq9uuyEr0",
"url": "http://pasture-one-actor/actor/UFwq9uuyEr0",
"account": {
"id": "9zzm83xete6p0002",
"username": "actor",
"acct": "actor@pasture-one-actor",
"fqn": "actor@pasture-one-actor",
"display_name": "Test Actor",
"locked": false,
"created_at": "2024-10-30T15:48:24.674Z",
"followers_count": 0,
"following_count": 0,
"statuses_count": 28,
"note": "",
"url": "http://pasture-one-actor/actor",
"uri": "http://pasture-one-actor/actor",
"avatar": "https://dev.joinsharkey.org/static-assets/avatar.png",
"avatar_static": "https://dev.joinsharkey.org/static-assets/avatar.png",
"header": "https://dev.joinsharkey.org/static-assets/transparent.png",
"header_static": "https://dev.joinsharkey.org/static-assets/transparent.png",
"emojis": [],
"moved": null,
"fields": [],
"bot": false,
"discoverable": true
},
"in_reply_to_id": null,
"in_reply_to_account_id": null,
"reblog": null,
"content": "<p><span>text</span></p>",
"content_type": "text/x.misskeymarkdown",
"text": "text",
"created_at": "2024-10-30T15:49:54.000Z",
"emojis": [],
"replies_count": 0,
"reblogs_count": 0,
"favourites_count": 0,
"reblogged": false,
"favourited": false,
"muted": false,
"sensitive": false,
"spoiler_text": "",
"visibility": "public",
"media_attachments": [
{
"id": "9zzma1p6te6p0011",
"type": "image",
"url": "http://pasture-one-actor/assets/FediverseLogo.png",
"remote_url": "http://pasture-one-actor/assets/FediverseLogo.png",
"preview_url": "http://pasture-one-actor/assets/FediverseLogo.png",
"text_url": "http://pasture-one-actor/assets/FediverseLogo.png",
"meta": {
"width": 1548,
"height": 1548
},
"description": "name",
"blurhash": "eQE_?c.}4.YJM^}fi{EVw[xu9JK[M~xI-T9+TJRPX2$$E]NFo}j1tO"
}
],
"mentions": [],
"tags": [],
"card": null,
"poll": null,
"application": null,
"language": null,
"pinned": false,
"reactions": [],
"emoji_reactions": [],
"bookmarked": false,
"quote": null,
"edited_at": null
}
Example 4¶
activity
{
"@context": [
"https://www.w3.org/ns/activitystreams",
{
"Hashtag": "as:Hashtag",
"sensitive": "as:sensitive"
}
],
"type": "Create",
"actor": "http://pasture-one-actor/actor",
"to": [
"http://hollo/@john",
"https://www.w3.org/ns/activitystreams#Public"
],
"id": "http://pasture-one-actor/actor/v9Y-wfBYfT0",
"published": "2024-10-30T15:56:50Z",
"object": {
"type": "Note",
"attributedTo": "http://pasture-one-actor/actor",
"to": [
"https://www.w3.org/ns/activitystreams#Public",
"http://hollo/@john"
],
"id": "http://pasture-one-actor/actor/p4ekxQn-s6s",
"published": "2024-10-30T15:56:50Z",
"content": "no comment in attachment",
"attachment": [
{
"type": "Document",
"url": "http://pasture-one-actor/assets/FediverseLogo.png"
}
],
"tag": [
{
"type": "Mention",
"href": "http://gotosocial/users/cookie"
}
]
}
}
hollo
{
"id": "0192de24-d9d0-74b7-a437-414d1d751a22",
"created_at": "2024-10-30T15:56:50.000Z",
"in_reply_to_id": null,
"sensitive": false,
"spoiler_text": "",
"visibility": "public",
"language": null,
"uri": "http://pasture-one-actor/actor/p4ekxQn-s6s",
"url": null,
"replies_count": 0,
"reblogs_count": 0,
"favourites_count": 0,
"favourited": false,
"reblogged": false,
"muted": false,
"bookmarked": false,
"pinned": false,
"content": "no comment in attachment",
"reblog": null,
"quote_id": null,
"quote": null,
"application": null,
"account": {
"id": "0192de24-1e6d-712c-9efb-1801e3b352b1",
"username": "actor",
"acct": "actor@pasture-one-actor",
"display_name": "Test Actor",
"locked": false,
"bot": false,
"created_at": "2024-10-30T15:56:01.966Z",
"note": "",
"url": "http://pasture-one-actor/actor",
"avatar": "http://hollo/image/avatars/original/missing.png",
"avatar_static": "http://hollo/image/avatars/original/missing.png",
"header": "http://hollo/image/headers/original/missing.png",
"header_static": "http://hollo/image/headers/original/missing.png",
"followers_count": 0,
"following_count": 0,
"statuses_count": 0,
"moved": null,
"last_status_at": null,
"emojis": [],
"fields": []
},
"media_attachments": [
{
"id": "0192de24-dbf8-7bde-9eeb-0ccb7ac6e9be",
"type": "image",
"url": "http://pasture-one-actor/assets/FediverseLogo.png",
"preview_url": "http://pasture-one-actor/assets/FediverseLogo.png",
"remote_url": null,
"text_url": null,
"meta": {
"original": {
"width": 512,
"height": 512,
"size": "512x512",
"aspect": 1
},
"small": {
"width": 512,
"height": 512,
"size": "512x512",
"aspect": 1
},
"focus": {
"x": 0,
"y": 0
}
},
"description": null,
"blurhash": null
}
],
"mentions": [],
"tags": [],
"card": null,
"emojis": [],
"emoji_reactions": [],
"poll": null,
"filtered": null
}
sharkey
{
"id": "9zzma1mgte6p0013",
"uri": "http://pasture-one-actor/actor/dHkik7f8ITM",
"url": "http://pasture-one-actor/actor/dHkik7f8ITM",
"account": {
"id": "9zzm83xete6p0002",
"username": "actor",
"acct": "actor@pasture-one-actor",
"fqn": "actor@pasture-one-actor",
"display_name": "Test Actor",
"locked": false,
"created_at": "2024-10-30T15:48:24.674Z",
"followers_count": 0,
"following_count": 0,
"statuses_count": 29,
"note": "",
"url": "http://pasture-one-actor/actor",
"uri": "http://pasture-one-actor/actor",
"avatar": "https://dev.joinsharkey.org/static-assets/avatar.png",
"avatar_static": "https://dev.joinsharkey.org/static-assets/avatar.png",
"header": "https://dev.joinsharkey.org/static-assets/transparent.png",
"header_static": "https://dev.joinsharkey.org/static-assets/transparent.png",
"emojis": [],
"moved": null,
"fields": [],
"bot": false,
"discoverable": true
},
"in_reply_to_id": null,
"in_reply_to_account_id": null,
"reblog": null,
"content": "<p><span>no comment in attachment</span></p>",
"content_type": "text/x.misskeymarkdown",
"text": "no comment in attachment",
"created_at": "2024-10-30T15:49:55.000Z",
"emojis": [],
"replies_count": 0,
"reblogs_count": 0,
"favourites_count": 0,
"reblogged": false,
"favourited": false,
"muted": false,
"sensitive": false,
"spoiler_text": "",
"visibility": "public",
"media_attachments": [
{
"id": "9zzma1p6te6p0011",
"type": "image",
"url": "http://pasture-one-actor/assets/FediverseLogo.png",
"remote_url": "http://pasture-one-actor/assets/FediverseLogo.png",
"preview_url": "http://pasture-one-actor/assets/FediverseLogo.png",
"text_url": "http://pasture-one-actor/assets/FediverseLogo.png",
"meta": {
"width": 1548,
"height": 1548
},
"description": "name",
"blurhash": "eQE_?c.}4.YJM^}fi{EVw[xu9JK[M~xI-T9+TJRPX2$$E]NFo}j1tO"
}
],
"mentions": [],
"tags": [],
"card": null,
"poll": null,
"application": null,
"language": null,
"pinned": false,
"reactions": [],
"emoji_reactions": [],
"bookmarked": false,
"quote": null,
"edited_at": null
}