Developer Docs/Seedance 2.x Video API

Seedance 2.x Video API

Build Seedance 2.x Video integrations with A2E. Review authentication, request parameters, task creation, status, and result endpoints.

Overview

Build Seedance 2.x Video integrations with A2E. Review authentication, request parameters, task creation, status, and result endpoints.

Primary Endpoint

POST/api/v1/seedance2Video/start

Start Seedance 2.x video generation

Request Parameters

NameTypeRequiredDescription
namestringNo-
modeenum: text-to-video | image-to-video | first-last-frames | referenceNoimage-to-video uses image_url (+ optional last_frame_url); first-last-frames uses first_frame_url + last_frame_url; reference accepts any combination of reference_urls (image) / video_urls / audio_urls. On Seedance 2.0 audio cannot be used alone and must accompany at least one image or video reference; on Seedance 2.5 audio-only references are supported.
model_versionenum: standard | mini | fast | 2.5Nostandard / mini / fast select a Seedance 2.0 tier. "2.5" selects Seedance 2.5, which currently has a single tier and higher input limits (see duration / reference_urls / video_urls / audio_urls).
omni_reference_task_typeenum: reference | edit | extendNoSeedance 2.5 reference-mode task hint. edit uses ratio=adaptive and duration=-1; extend uses ratio=adaptive; reference keeps the requested ratio and duration. edit currently accepts exactly one video_url. auto is intentionally not exposed because its output duration is unknown before billing.
promptstringYes-
image_urlstringNoFirst frame for image-to-video mode.
first_frame_urlstringNoRequired for first-last-frames mode.
last_frame_urlstringNoOptional last frame for image-to-video; required for first-last-frames.
reference_urlsarray<string>NoReference images for reference mode. Max 9 on Seedance 2.0, max 30 on Seedance 2.5.
video_urlsarray<string>NoReference videos (mp4/mov). Seedance 2.0: max 3 clips, each 2-15s, total <= 15 × number_of_videos seconds. Seedance 2.5: max 10 clips with a combined cap of 30s; omni_reference_task_type=edit currently requires exactly one clip. The server always probes video_urls (public hosts only, with separate connection/download/parse limits) as the authoritative duration for billing.
audio_urlsarray<string>NoReference audios (mp3/wav). Seedance 2.0: max 3 clips, each 2-15s, total <=15s, and audio cannot be used standalone (at least one image or video reference is required). Seedance 2.5: max 10 clips and audio-only references are allowed.
input_video_durationnumberNoOptional client estimate of the total reference-video duration in seconds. This value is never trusted for final billing: the server always probes video_urls and bills on max(measured, this value), so passing a smaller number does not lower the price. Must be within [2, 15 × number_of_videos] on Seedance 2.0 and within [2, 30] on Seedance 2.5.
durationintegerNoOutput length in seconds. Max 15 on Seedance 2.0; max 30 on Seedance 2.5. Seedance 2.5 edit tasks require -1.
aspect_ratioenum: adaptive | 21:9 | 16:9 | 4:3 | 1:1 | 3:4 | 9:16No-
resolutionenum: 480p | 720p | 1080p | 4kNoOnly the standard tier of Seedance 2.0 supports 4k. Seedance 2.5 supports 480p / 720p / 1080p. The fast / mini tiers of Seedance 2.0 are limited to 480p / 720p.
generate_audiobooleanNoDefaults to true to match billing (audio is included); pass false explicitly to disable.
minor_suspected_skipbooleanNoSkip soft minor-suspect block (code 1004); hard CSAM block (code 1003) is always enforced.
webhook_urlstringNoHTTPS URL to receive task.completed / task.failed notifications. Best-effort delivery, single attempt, no retries; clients should treat the detail API as the source of truth.
webhook_tokenstringNoOptional plaintext token returned in the X-A2e-Webhook-Token header so receivers can verify the request originated from a2e.

Request Example

curl -X POST "https://www.a2e.com.cn/api/v1/seedance2Video/start" \
  -H "Authorization: Bearer YOUR_API_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
  "name": "My generation task",
  "mode": "text-to-video",
  "model_version": "standard",
  "omni_reference_task_type": "reference",
  "prompt": "A cinematic scene with natural motion",
  "image_url": "https://example.com/reference.jpg",
  "first_frame_url": "https://example.com/reference.jpg",
  "last_frame_url": "https://example.com/reference.jpg",
  "reference_urls": "https://example.com/reference.jpg",
  "video_urls": "https://example.com/reference.jpg",
  "audio_urls": "https://example.com/reference.jpg",
  "input_video_duration": 1
}'

Responses

200

Task started successfully

401

Unauthorized - Invalid or missing bearer token