Recommended Media Attachment Format¶
The first three example are our recommendation on how to format image, video, and audio media attachments. Further properties are possible, and might make it into this recommendation at one point. Examples:
- Focal point and blurhash, see Mastodon
- fps (frames per second) for videos
The final example cannot be recommended yet as it is not widely supported. However, it illustrates how one can provide multiple versions of the media attachments. A high quality and low quality video in this case. The low quality video is enough for most use cases, and is 40 times smaller.
The recommended format is documented in FEP-1311: Media Attachments.
Examples¶
Example 1¶
activity
{
"@context": [
"https://www.w3.org/ns/activitystreams",
"https://www.w3.org/ns/credentials/v2",
{
"size": "https://joinpeertube.org/ns#size"
}
],
"type": "Create",
"actor": "http://pasture-one-actor/actor",
"to": [
"http://mastodon/users/hippo",
"https://www.w3.org/ns/activitystreams#Public"
],
"id": "http://pasture-one-actor/activity/bJ3xBV-5VRc",
"published": "2025-09-01T07:48:54Z",
"object": {
"type": "Note",
"attributedTo": "http://pasture-one-actor/actor",
"to": [
"https://www.w3.org/ns/activitystreams#Public",
"http://mastodon/users/hippo"
],
"id": "http://pasture-one-actor/object/KuZ9SQXpzq4",
"published": "2025-09-01T07:48:54Z",
"@context": [
"https://www.w3.org/ns/activitystreams",
"https://www.w3.org/ns/credentials/v2",
{
"size": "https://joinpeertube.org/ns#size"
}
],
"content": "Recommended Image Format",
"attachment": [
{
"type": "Image",
"name": "A beautiful cow",
"url": "http://pasture-one-actor/assets/cow.jpg",
"width": 100,
"height": 162,
"mediaType": "image/jpeg",
"digestMultibase": "zQmaeDPzhNL32WQZnnzB1H6QJWvvFNEHdViDB71yrxyXU1t",
"size": 9045
}
]
}
}
mastodon
{
"id": "115127938925743444",
"created_at": "2025-09-01T07:48:54.000Z",
"in_reply_to_id": null,
"in_reply_to_account_id": null,
"sensitive": false,
"spoiler_text": "",
"visibility": "public",
"language": null,
"uri": "http://pasture-one-actor/object/KuZ9SQXpzq4",
"url": "http://pasture-one-actor/object/KuZ9SQXpzq4",
"replies_count": 0,
"reblogs_count": 0,
"favourites_count": 0,
"edited_at": null,
"favourited": false,
"reblogged": false,
"muted": false,
"bookmarked": false,
"content": "Recommended Image Format",
"filtered": [],
"reblog": null,
"account": {
"id": "115127934701944957",
"username": "actor",
"acct": "actor@pasture-one-actor",
"display_name": "Test Actor",
"locked": false,
"bot": false,
"discoverable": false,
"indexable": false,
"group": false,
"created_at": "2025-09-01T00:00:00.000Z",
"note": "",
"url": "http://pasture-one-actor/actor",
"uri": "http://pasture-one-actor/actor",
"avatar": "http://mastodon/avatars/original/missing.png",
"avatar_static": "http://mastodon/avatars/original/missing.png",
"header": "http://mastodon/headers/original/missing.png",
"header_static": "http://mastodon/headers/original/missing.png",
"followers_count": 0,
"following_count": 0,
"statuses_count": 33,
"last_status_at": "2025-09-01",
"hide_collections": true,
"emojis": [],
"fields": []
},
"media_attachments": [
{
"id": "115127938919744116",
"type": "image",
"url": "http://localhost:2970/system/cache/media_attachments/files/115/127/938/919/744/116/original/8d788970619e165c.jpg",
"preview_url": "http://localhost:2970/system/cache/media_attachments/files/115/127/938/919/744/116/small/8d788970619e165c.jpg",
"remote_url": "http://pasture-one-actor/assets/cow.jpg",
"preview_remote_url": null,
"text_url": null,
"meta": {
"original": {
"width": 200,
"height": 164,
"size": "200x164",
"aspect": 1.2195121951219512
},
"small": {
"width": 200,
"height": 164,
"size": "200x164",
"aspect": 1.2195121951219512
}
},
"description": "A beautiful cow",
"blurhash": "UjL4Z_Di_3s._4%gNHRkyEWBMxt7kDV@aJbH"
}
],
"mentions": [],
"tags": [],
"emojis": [],
"quote": null,
"card": null,
"poll": null
}
Example 2¶
activity
{
"@context": [
"https://www.w3.org/ns/activitystreams",
"https://www.w3.org/ns/credentials/v2",
{
"size": "https://joinpeertube.org/ns#size"
}
],
"type": "Create",
"actor": "http://pasture-one-actor/actor",
"to": [
"http://mastodon/users/hippo",
"https://www.w3.org/ns/activitystreams#Public"
],
"id": "http://pasture-one-actor/activity/xnL8cdPqUrM",
"published": "2025-09-01T07:48:55Z",
"object": {
"type": "Note",
"attributedTo": "http://pasture-one-actor/actor",
"to": [
"https://www.w3.org/ns/activitystreams#Public",
"http://mastodon/users/hippo"
],
"id": "http://pasture-one-actor/object/QaeH_3B5T_4",
"published": "2025-09-01T07:48:55Z",
"@context": [
"https://www.w3.org/ns/activitystreams",
"https://www.w3.org/ns/credentials/v2",
{
"size": "https://joinpeertube.org/ns#size"
}
],
"content": "Recommended Video Attachment",
"attachment": [
{
"type": "Video",
"url": "http://pasture-one-actor/assets/cow_eating.mp4",
"name": "A beautiful cow eating",
"width": 256,
"height": 144,
"mediaType": "video/mp4",
"digestMultibase": "zQmSzK5qEe5tpjwGMhmjx9RvVoPkWhEmCwxP2s7wPMpKMoK",
"size": 54373,
"duration": "PT3S"
}
]
}
}
mastodon
{
"id": "115127939007763582",
"created_at": "2025-09-01T07:48:55.000Z",
"in_reply_to_id": null,
"in_reply_to_account_id": null,
"sensitive": false,
"spoiler_text": "",
"visibility": "public",
"language": null,
"uri": "http://pasture-one-actor/object/QaeH_3B5T_4",
"url": "http://pasture-one-actor/object/QaeH_3B5T_4",
"replies_count": 0,
"reblogs_count": 0,
"favourites_count": 0,
"edited_at": null,
"favourited": false,
"reblogged": false,
"muted": false,
"bookmarked": false,
"content": "Recommended Video Attachment",
"filtered": [],
"reblog": null,
"account": {
"id": "115127934701944957",
"username": "actor",
"acct": "actor@pasture-one-actor",
"display_name": "Test Actor",
"locked": false,
"bot": false,
"discoverable": false,
"indexable": false,
"group": false,
"created_at": "2025-09-01T00:00:00.000Z",
"note": "",
"url": "http://pasture-one-actor/actor",
"uri": "http://pasture-one-actor/actor",
"avatar": "http://mastodon/avatars/original/missing.png",
"avatar_static": "http://mastodon/avatars/original/missing.png",
"header": "http://mastodon/headers/original/missing.png",
"header_static": "http://mastodon/headers/original/missing.png",
"followers_count": 0,
"following_count": 0,
"statuses_count": 34,
"last_status_at": "2025-09-01",
"hide_collections": true,
"emojis": [],
"fields": []
},
"media_attachments": [
{
"id": "115127938984916629",
"type": "gifv",
"url": "http://localhost:2970/system/cache/media_attachments/files/115/127/938/984/916/629/original/95addee2767ce6d3.mp4",
"preview_url": "http://localhost:2970/system/cache/media_attachments/files/115/127/938/984/916/629/small/95addee2767ce6d3.png",
"remote_url": "http://pasture-one-actor/assets/cow_eating.mp4",
"preview_remote_url": null,
"text_url": null,
"meta": {
"original": {
"width": 256,
"height": 144,
"frame_rate": "25/1",
"duration": 3.0,
"bitrate": 144994
},
"small": {
"width": 256,
"height": 144,
"size": "256x144",
"aspect": 1.7777777777777777
}
},
"description": "A beautiful cow eating",
"blurhash": "UTEMdgveNaXU-trVWCOFKRNFnPWCKPNdn#xE"
}
],
"mentions": [],
"tags": [],
"emojis": [],
"quote": null,
"card": null,
"poll": null
}
Example 3¶
activity
{
"@context": [
"https://www.w3.org/ns/activitystreams",
"https://www.w3.org/ns/credentials/v2",
{
"size": "https://joinpeertube.org/ns#size"
}
],
"type": "Create",
"actor": "http://pasture-one-actor/actor",
"to": [
"http://mastodon/users/hippo",
"https://www.w3.org/ns/activitystreams#Public"
],
"id": "http://pasture-one-actor/activity/yoiwZ7mxdTc",
"published": "2025-09-01T07:48:56Z",
"object": {
"type": "Note",
"attributedTo": "http://pasture-one-actor/actor",
"to": [
"https://www.w3.org/ns/activitystreams#Public",
"http://mastodon/users/hippo"
],
"id": "http://pasture-one-actor/object/quYf2z8WZ3M",
"published": "2025-09-01T07:48:56Z",
"@context": [
"https://www.w3.org/ns/activitystreams",
"https://www.w3.org/ns/credentials/v2",
{
"size": "https://joinpeertube.org/ns#size"
}
],
"content": "Recommended Audio Format",
"attachment": [
{
"type": "Audio",
"url": "http://pasture-one-actor/assets/cow_moo.mp3",
"name": "A cow mooing",
"mediaType": "audio/mpeg",
"digestMultibase": "zQmSXTyLCPqoiGoUUwKRMKgFdddaAUkvQNr29nhB6tahb9Z",
"size": 67709,
"duration": "PT2.1S"
}
]
}
}
mastodon
{
"id": "115127939058730859",
"created_at": "2025-09-01T07:48:56.000Z",
"in_reply_to_id": null,
"in_reply_to_account_id": null,
"sensitive": false,
"spoiler_text": "",
"visibility": "public",
"language": null,
"uri": "http://pasture-one-actor/object/quYf2z8WZ3M",
"url": "http://pasture-one-actor/object/quYf2z8WZ3M",
"replies_count": 0,
"reblogs_count": 0,
"favourites_count": 0,
"edited_at": null,
"favourited": false,
"reblogged": false,
"muted": false,
"bookmarked": false,
"content": "Recommended Audio Format",
"filtered": [],
"reblog": null,
"account": {
"id": "115127934701944957",
"username": "actor",
"acct": "actor@pasture-one-actor",
"display_name": "Test Actor",
"locked": false,
"bot": false,
"discoverable": false,
"indexable": false,
"group": false,
"created_at": "2025-09-01T00:00:00.000Z",
"note": "",
"url": "http://pasture-one-actor/actor",
"uri": "http://pasture-one-actor/actor",
"avatar": "http://mastodon/avatars/original/missing.png",
"avatar_static": "http://mastodon/avatars/original/missing.png",
"header": "http://mastodon/headers/original/missing.png",
"header_static": "http://mastodon/headers/original/missing.png",
"followers_count": 0,
"following_count": 0,
"statuses_count": 35,
"last_status_at": "2025-09-01",
"hide_collections": true,
"emojis": [],
"fields": []
},
"media_attachments": [
{
"id": "115127939047636365",
"type": "audio",
"url": "http://localhost:2970/system/cache/media_attachments/files/115/127/939/047/636/365/original/6b982e86bcb8c053.mp3",
"preview_url": null,
"remote_url": "http://pasture-one-actor/assets/cow_moo.mp3",
"preview_remote_url": null,
"text_url": null,
"meta": {
"original": {
"duration": 2.142041,
"bitrate": 131018
}
},
"description": "A cow mooing",
"blurhash": null
}
],
"mentions": [],
"tags": [],
"emojis": [],
"quote": null,
"card": null,
"poll": null
}
Example 4¶
activity
{
"@context": [
"https://www.w3.org/ns/activitystreams",
"https://www.w3.org/ns/credentials/v2",
{
"size": "https://joinpeertube.org/ns#size"
}
],
"type": "Create",
"actor": "http://pasture-one-actor/actor",
"to": [
"http://mastodon/users/hippo",
"https://www.w3.org/ns/activitystreams#Public"
],
"id": "http://pasture-one-actor/activity/sVG7i2Sdv9c",
"published": "2025-09-01T07:48:57Z",
"object": {
"type": "Note",
"attributedTo": "http://pasture-one-actor/actor",
"to": [
"https://www.w3.org/ns/activitystreams#Public",
"http://mastodon/users/hippo"
],
"id": "http://pasture-one-actor/object/hWpSKmgGOMk",
"published": "2025-09-01T07:48:57Z",
"@context": [
"https://www.w3.org/ns/activitystreams",
"https://www.w3.org/ns/credentials/v2",
{
"size": "https://joinpeertube.org/ns#size"
}
],
"content": "Multiple formats for video",
"attachment": [
{
"type": "Video",
"name": "A beautiful cow eating",
"url": [
{
"type": "Link",
"size": 54373,
"digest": "zQmSzK5qEe5tpjwGMhmjx9RvVoPkWhEmCwxP2s7wPMpKMoK",
"width": 256,
"height": 144,
"href": "http://pasture-one-actor/assets/cow_eating.mp4",
"mediaType": "video/mp4"
},
{
"type": "Link",
"size": 2271723,
"digest": "zQme2X4rgWuRdmAtGGMSEbdoeRQ2NAL2VptcdRGTYDZbSKG",
"width": 1920,
"height": 1080,
"href": "http://pasture-one-actor/assets/cow_eating_hd.mp4",
"mediaType": "video/mp4"
}
],
"duration": "PT3S"
}
]
}
}
mastodon
{
"id": "115127939129309465",
"created_at": "2025-09-01T07:48:57.000Z",
"in_reply_to_id": null,
"in_reply_to_account_id": null,
"sensitive": false,
"spoiler_text": "",
"visibility": "public",
"language": null,
"uri": "http://pasture-one-actor/object/hWpSKmgGOMk",
"url": "http://pasture-one-actor/object/hWpSKmgGOMk",
"replies_count": 0,
"reblogs_count": 0,
"favourites_count": 0,
"edited_at": null,
"favourited": false,
"reblogged": false,
"muted": false,
"bookmarked": false,
"content": "Multiple formats for video",
"filtered": [],
"reblog": null,
"account": {
"id": "115127934701944957",
"username": "actor",
"acct": "actor@pasture-one-actor",
"display_name": "Test Actor",
"locked": false,
"bot": false,
"discoverable": false,
"indexable": false,
"group": false,
"created_at": "2025-09-01T00:00:00.000Z",
"note": "",
"url": "http://pasture-one-actor/actor",
"uri": "http://pasture-one-actor/actor",
"avatar": "http://mastodon/avatars/original/missing.png",
"avatar_static": "http://mastodon/avatars/original/missing.png",
"header": "http://mastodon/headers/original/missing.png",
"header_static": "http://mastodon/headers/original/missing.png",
"followers_count": 0,
"following_count": 0,
"statuses_count": 36,
"last_status_at": "2025-09-01",
"hide_collections": true,
"emojis": [],
"fields": []
},
"media_attachments": [
{
"id": "115127939114903024",
"type": "gifv",
"url": "http://localhost:2970/system/cache/media_attachments/files/115/127/939/114/903/024/original/652dc1b4aaebdd94.mp4",
"preview_url": "http://localhost:2970/system/cache/media_attachments/files/115/127/939/114/903/024/small/652dc1b4aaebdd94.png",
"remote_url": "http://pasture-one-actor/assets/cow_eating.mp4",
"preview_remote_url": null,
"text_url": null,
"meta": {
"original": {
"width": 256,
"height": 144,
"frame_rate": "25/1",
"duration": 3.0,
"bitrate": 144994
},
"small": {
"width": 256,
"height": 144,
"size": "256x144",
"aspect": 1.7777777777777777
}
},
"description": "A beautiful cow eating",
"blurhash": "UTEMdgveNaXU-trVWCOFKRNFnPWCKPNdn#xE"
}
],
"mentions": [],
"tags": [],
"emojis": [],
"quote": null,
"card": null,
"poll": null
}