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": [
"https://www.w3.org/ns/activitystreams#Public",
"http://pleroma/users/full"
],
"id": "http://pasture-one-actor/actor/xVaK6Itzuto",
"published": "2024-12-04T18:45:24Z",
"object": {
"type": "Note",
"attributedTo": "http://pasture-one-actor/actor",
"to": [
"https://www.w3.org/ns/activitystreams#Public",
"http://pleroma/users/full"
],
"id": "http://pasture-one-actor/actor/zGJOGSd5Ebs",
"published": "2024-12-04T18:45:24Z",
"content": "no description",
"attachment": {
"type": "Document",
"url": "http://pasture-one-actor/images/100.png"
}
}
}
pleroma
{
"account": {
"acct": "actor@pasture-one-actor",
"avatar": "http://pleroma/images/avi.png",
"avatar_static": "http://pleroma/images/avi.png",
"bot": false,
"created_at": "2024-12-04T18:42:53.000Z",
"display_name": "Test Actor",
"emojis": [],
"fields": [],
"followers_count": 0,
"following_count": 0,
"fqn": "actor@pasture-one-actor",
"header": "http://pleroma/images/banner.png",
"header_static": "http://pleroma/images/banner.png",
"id": "Aoi7pYzQO3IsiU4NSS",
"last_status_at": "2024-12-04",
"locked": false,
"note": "",
"pleroma": {
"accepts_chat_messages": null,
"also_known_as": [],
"ap_id": "http://pasture-one-actor/actor",
"background_image": null,
"favicon": null,
"hide_favorites": true,
"hide_followers": false,
"hide_followers_count": false,
"hide_follows": false,
"hide_follows_count": false,
"is_admin": false,
"is_confirmed": true,
"is_moderator": false,
"is_suggested": false,
"privileges": [],
"relationship": {},
"skip_thread_containment": false,
"tags": []
},
"source": {
"fields": [],
"note": "",
"pleroma": {
"actor_type": "Person",
"discoverable": false
},
"sensitive": false
},
"statuses_count": 23,
"url": "http://pasture-one-actor/actor",
"username": "actor"
},
"application": null,
"bookmarked": false,
"card": null,
"content": "no description",
"created_at": "2024-12-04T18:45:24.000Z",
"edited_at": null,
"emojis": [],
"favourited": false,
"favourites_count": 0,
"id": "Aoi83YqZiLyWKObZAm",
"in_reply_to_account_id": null,
"in_reply_to_id": null,
"language": null,
"media_attachments": [
{
"blurhash": null,
"description": null,
"id": "983810756",
"pleroma": {
"mime_type": "application/octet-stream"
},
"preview_url": "http://pasture-one-actor/images/100.png",
"remote_url": "http://pasture-one-actor/images/100.png",
"text_url": "http://pasture-one-actor/images/100.png",
"type": "unknown",
"url": "http://pasture-one-actor/images/100.png"
}
],
"mentions": [
{
"acct": "full",
"id": "Aoi7hxsZq3aJcKZCNM",
"url": "http://pleroma/users/full",
"username": "full"
}
],
"muted": false,
"pinned": false,
"pleroma": {
"bookmark_folder": null,
"content": {
"text/plain": "no description"
},
"context": "http://pasture-one-actor/actor/zGJOGSd5Ebs",
"conversation_id": 368720806,
"direct_conversation_id": null,
"emoji_reactions": [],
"expires_at": null,
"in_reply_to_account_acct": null,
"local": false,
"parent_visible": false,
"pinned_at": null,
"quote": null,
"quote_id": null,
"quote_url": null,
"quote_visible": false,
"quotes_count": 0,
"spoiler_text": {
"text/plain": ""
},
"thread_muted": false
},
"poll": null,
"reblog": null,
"reblogged": false,
"reblogs_count": 0,
"replies_count": 0,
"sensitive": false,
"spoiler_text": "",
"tags": [],
"text": null,
"uri": "http://pasture-one-actor/actor/zGJOGSd5Ebs",
"url": "http://pasture-one-actor/actor/zGJOGSd5Ebs",
"visibility": "public"
}
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": [
"https://www.w3.org/ns/activitystreams#Public",
"http://pleroma/users/full"
],
"id": "http://pasture-one-actor/actor/UhAMViJA14U",
"published": "2024-12-04T18:45:25Z",
"object": {
"type": "Note",
"attributedTo": "http://pasture-one-actor/actor",
"to": [
"https://www.w3.org/ns/activitystreams#Public",
"http://pleroma/users/full"
],
"id": "http://pasture-one-actor/actor/dkNR0O9UcYY",
"published": "2024-12-04T18:45:25Z",
"content": "text",
"attachment": {
"type": "Document",
"url": "http://pasture-one-actor/images/100.png",
"name": "name",
"summary": "summary",
"content": "content"
}
}
}
pleroma
{
"account": {
"acct": "actor@pasture-one-actor",
"avatar": "http://pleroma/images/avi.png",
"avatar_static": "http://pleroma/images/avi.png",
"bot": false,
"created_at": "2024-12-04T18:42:53.000Z",
"display_name": "Test Actor",
"emojis": [],
"fields": [],
"followers_count": 0,
"following_count": 0,
"fqn": "actor@pasture-one-actor",
"header": "http://pleroma/images/banner.png",
"header_static": "http://pleroma/images/banner.png",
"id": "Aoi7pYzQO3IsiU4NSS",
"last_status_at": "2024-12-04",
"locked": false,
"note": "",
"pleroma": {
"accepts_chat_messages": null,
"also_known_as": [],
"ap_id": "http://pasture-one-actor/actor",
"background_image": null,
"favicon": null,
"hide_favorites": true,
"hide_followers": false,
"hide_followers_count": false,
"hide_follows": false,
"hide_follows_count": false,
"is_admin": false,
"is_confirmed": true,
"is_moderator": false,
"is_suggested": false,
"privileges": [],
"relationship": {},
"skip_thread_containment": false,
"tags": []
},
"source": {
"fields": [],
"note": "",
"pleroma": {
"actor_type": "Person",
"discoverable": false
},
"sensitive": false
},
"statuses_count": 24,
"url": "http://pasture-one-actor/actor",
"username": "actor"
},
"application": null,
"bookmarked": false,
"card": null,
"content": "text",
"created_at": "2024-12-04T18:45:25.000Z",
"edited_at": null,
"emojis": [],
"favourited": false,
"favourites_count": 0,
"id": "Aoi83cr4oQkkl6s1Vg",
"in_reply_to_account_id": null,
"in_reply_to_id": null,
"language": null,
"media_attachments": [
{
"blurhash": null,
"description": "summary",
"id": "983810756",
"pleroma": {
"mime_type": "application/octet-stream",
"name": "name"
},
"preview_url": "http://pasture-one-actor/images/100.png",
"remote_url": "http://pasture-one-actor/images/100.png",
"text_url": "http://pasture-one-actor/images/100.png",
"type": "unknown",
"url": "http://pasture-one-actor/images/100.png"
}
],
"mentions": [
{
"acct": "full",
"id": "Aoi7hxsZq3aJcKZCNM",
"url": "http://pleroma/users/full",
"username": "full"
}
],
"muted": false,
"pinned": false,
"pleroma": {
"bookmark_folder": null,
"content": {
"text/plain": "text"
},
"context": "http://pasture-one-actor/actor/dkNR0O9UcYY",
"conversation_id": 2080280131,
"direct_conversation_id": null,
"emoji_reactions": [],
"expires_at": null,
"in_reply_to_account_acct": null,
"local": false,
"parent_visible": false,
"pinned_at": null,
"quote": null,
"quote_id": null,
"quote_url": null,
"quote_visible": false,
"quotes_count": 0,
"spoiler_text": {
"text/plain": ""
},
"thread_muted": false
},
"poll": null,
"reblog": null,
"reblogged": false,
"reblogs_count": 0,
"replies_count": 0,
"sensitive": false,
"spoiler_text": "",
"tags": [],
"text": null,
"uri": "http://pasture-one-actor/actor/dkNR0O9UcYY",
"url": "http://pasture-one-actor/actor/dkNR0O9UcYY",
"visibility": "public"
}
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": [
"https://www.w3.org/ns/activitystreams#Public",
"http://pleroma/users/full"
],
"id": "http://pasture-one-actor/actor/p4EYLCRez8Y",
"published": "2024-12-04T18:45:26Z",
"object": {
"type": "Note",
"attributedTo": "http://pasture-one-actor/actor",
"to": [
"https://www.w3.org/ns/activitystreams#Public",
"http://pleroma/users/full"
],
"id": "http://pasture-one-actor/actor/GHNso1Leqxg",
"published": "2024-12-04T18:45:26Z",
"content": "text",
"attachment": [
{
"type": "Document",
"url": "http://pasture-one-actor/assets/FediverseLogo.png",
"name": "name",
"imageType": "image/jpeg"
}
]
}
}
pleroma
{
"account": {
"acct": "actor@pasture-one-actor",
"avatar": "http://pleroma/images/avi.png",
"avatar_static": "http://pleroma/images/avi.png",
"bot": false,
"created_at": "2024-12-04T18:42:53.000Z",
"display_name": "Test Actor",
"emojis": [],
"fields": [],
"followers_count": 0,
"following_count": 0,
"fqn": "actor@pasture-one-actor",
"header": "http://pleroma/images/banner.png",
"header_static": "http://pleroma/images/banner.png",
"id": "Aoi7pYzQO3IsiU4NSS",
"last_status_at": "2024-12-04",
"locked": false,
"note": "",
"pleroma": {
"accepts_chat_messages": null,
"also_known_as": [],
"ap_id": "http://pasture-one-actor/actor",
"background_image": null,
"favicon": null,
"hide_favorites": true,
"hide_followers": false,
"hide_followers_count": false,
"hide_follows": false,
"hide_follows_count": false,
"is_admin": false,
"is_confirmed": true,
"is_moderator": false,
"is_suggested": false,
"privileges": [],
"relationship": {},
"skip_thread_containment": false,
"tags": []
},
"source": {
"fields": [],
"note": "",
"pleroma": {
"actor_type": "Person",
"discoverable": false
},
"sensitive": false
},
"statuses_count": 25,
"url": "http://pasture-one-actor/actor",
"username": "actor"
},
"application": null,
"bookmarked": false,
"card": null,
"content": "text",
"created_at": "2024-12-04T18:45:26.000Z",
"edited_at": null,
"emojis": [],
"favourited": false,
"favourites_count": 0,
"id": "Aoi83gv7hKMnMonJNA",
"in_reply_to_account_id": null,
"in_reply_to_id": null,
"language": null,
"media_attachments": [
{
"blurhash": null,
"description": "name",
"id": "-751667840",
"pleroma": {
"mime_type": "application/octet-stream"
},
"preview_url": "http://pasture-one-actor/assets/FediverseLogo.png",
"remote_url": "http://pasture-one-actor/assets/FediverseLogo.png",
"text_url": "http://pasture-one-actor/assets/FediverseLogo.png",
"type": "unknown",
"url": "http://pasture-one-actor/assets/FediverseLogo.png"
}
],
"mentions": [
{
"acct": "full",
"id": "Aoi7hxsZq3aJcKZCNM",
"url": "http://pleroma/users/full",
"username": "full"
}
],
"muted": false,
"pinned": false,
"pleroma": {
"bookmark_folder": null,
"content": {
"text/plain": "text"
},
"context": "http://pasture-one-actor/actor/GHNso1Leqxg",
"conversation_id": 46571561,
"direct_conversation_id": null,
"emoji_reactions": [],
"expires_at": null,
"in_reply_to_account_acct": null,
"local": false,
"parent_visible": false,
"pinned_at": null,
"quote": null,
"quote_id": null,
"quote_url": null,
"quote_visible": false,
"quotes_count": 0,
"spoiler_text": {
"text/plain": ""
},
"thread_muted": false
},
"poll": null,
"reblog": null,
"reblogged": false,
"reblogs_count": 0,
"replies_count": 0,
"sensitive": false,
"spoiler_text": "",
"tags": [],
"text": null,
"uri": "http://pasture-one-actor/actor/GHNso1Leqxg",
"url": "http://pasture-one-actor/actor/GHNso1Leqxg",
"visibility": "public"
}
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": [
"https://www.w3.org/ns/activitystreams#Public",
"http://pleroma/users/full"
],
"id": "http://pasture-one-actor/actor/iLesCNTx9YI",
"published": "2024-12-04T18:45:27Z",
"object": {
"type": "Note",
"attributedTo": "http://pasture-one-actor/actor",
"to": [
"https://www.w3.org/ns/activitystreams#Public",
"http://pleroma/users/full"
],
"id": "http://pasture-one-actor/actor/opAc4JyZ4zw",
"published": "2024-12-04T18:45:27Z",
"content": "no comment in attachment",
"attachment": [
{
"type": "Document",
"url": "http://pasture-one-actor/assets/FediverseLogo.png"
}
]
}
}
pleroma
{
"account": {
"acct": "actor@pasture-one-actor",
"avatar": "http://pleroma/images/avi.png",
"avatar_static": "http://pleroma/images/avi.png",
"bot": false,
"created_at": "2024-12-04T18:42:53.000Z",
"display_name": "Test Actor",
"emojis": [],
"fields": [],
"followers_count": 0,
"following_count": 0,
"fqn": "actor@pasture-one-actor",
"header": "http://pleroma/images/banner.png",
"header_static": "http://pleroma/images/banner.png",
"id": "Aoi7pYzQO3IsiU4NSS",
"last_status_at": "2024-12-04",
"locked": false,
"note": "",
"pleroma": {
"accepts_chat_messages": null,
"also_known_as": [],
"ap_id": "http://pasture-one-actor/actor",
"background_image": null,
"favicon": null,
"hide_favorites": true,
"hide_followers": false,
"hide_followers_count": false,
"hide_follows": false,
"hide_follows_count": false,
"is_admin": false,
"is_confirmed": true,
"is_moderator": false,
"is_suggested": false,
"privileges": [],
"relationship": {},
"skip_thread_containment": false,
"tags": []
},
"source": {
"fields": [],
"note": "",
"pleroma": {
"actor_type": "Person",
"discoverable": false
},
"sensitive": false
},
"statuses_count": 26,
"url": "http://pasture-one-actor/actor",
"username": "actor"
},
"application": null,
"bookmarked": false,
"card": null,
"content": "no comment in attachment",
"created_at": "2024-12-04T18:45:27.000Z",
"edited_at": null,
"emojis": [],
"favourited": false,
"favourites_count": 0,
"id": "Aoi83kvym5QbodE3GK",
"in_reply_to_account_id": null,
"in_reply_to_id": null,
"language": null,
"media_attachments": [
{
"blurhash": null,
"description": null,
"id": "-751667840",
"pleroma": {
"mime_type": "application/octet-stream"
},
"preview_url": "http://pasture-one-actor/assets/FediverseLogo.png",
"remote_url": "http://pasture-one-actor/assets/FediverseLogo.png",
"text_url": "http://pasture-one-actor/assets/FediverseLogo.png",
"type": "unknown",
"url": "http://pasture-one-actor/assets/FediverseLogo.png"
}
],
"mentions": [
{
"acct": "full",
"id": "Aoi7hxsZq3aJcKZCNM",
"url": "http://pleroma/users/full",
"username": "full"
}
],
"muted": false,
"pinned": false,
"pleroma": {
"bookmark_folder": null,
"content": {
"text/plain": "no comment in attachment"
},
"context": "http://pasture-one-actor/actor/opAc4JyZ4zw",
"conversation_id": 1053904910,
"direct_conversation_id": null,
"emoji_reactions": [],
"expires_at": null,
"in_reply_to_account_acct": null,
"local": false,
"parent_visible": false,
"pinned_at": null,
"quote": null,
"quote_id": null,
"quote_url": null,
"quote_visible": false,
"quotes_count": 0,
"spoiler_text": {
"text/plain": ""
},
"thread_muted": false
},
"poll": null,
"reblog": null,
"reblogged": false,
"reblogs_count": 0,
"replies_count": 0,
"sensitive": false,
"spoiler_text": "",
"tags": [],
"text": null,
"uri": "http://pasture-one-actor/actor/opAc4JyZ4zw",
"url": "http://pasture-one-actor/actor/opAc4JyZ4zw",
"visibility": "public"
}