ListenHubOpenAPI
API ReferenceAI Video

HappyHorse

HappyHorse-specific model, limits, and constraints for the shared AI Video generation endpoint.

HappyHorse runs on the shared video generation endpoint. For the endpoint, request flow, content items, polling, task listing, and error codes, see the AI Video overview. This page covers only what is specific to HappyHorse.

Model

ModelBest forRate limit
happyhorseHappyHorse model workflows5 RPM

Pass "model": "happyhorse" in POST /v1/video-generation/generate.

Limits

LimitHappyHorse
Resolution720p, 1080p (no 480p)
Duration3-15s
Aspect ratios16:9, 4:3, 1:1, 3:4, 9:16, 21:9, 4:5, 5:4
inputVideoDuration3-60s (reference video input)

HappyHorse does not support 480p. It does not support last_frame (no end-frame control) or audio_url (no reference-audio input). HappyHorse is the only family that adds the 4:5 and 5:4 aspect ratios, and it accepts a longer reference-video input window (3-60s) than Seedance (2-15s).

Example

curl -X POST "https://api.marswave.ai/openapi/v1/video-generation/generate" \
  -H "Authorization: Bearer $LISTENHUB_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "happyhorse",
    "content": [
      { "type": "text", "text": "Restyle the subject as a polished product launch clip" },
      { "type": "video_url", "role": "reference_video", "video_url": { "url": "https://example.com/reference.mp4" } }
    ],
    "resolution": "1080p",
    "ratio": "4:5",
    "duration": 6,
    "inputVideoDuration": 8,
    "audioSetting": "auto"
  }'

See the AI Video overview for the full parameter list and the text-to-video / image-to-video request shapes.

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