UlazAI developer docs

HappyHorse Video API

Pricing Dashboard Image studio

HappyHorse reference

HappyHorse docs for T2V, I2V, reference-to-video, and video edit

Use POST /api/v1/video-studio/generate/ with one of these model slugs: happyhorse_t2v, happyhorse_i2v, happyhorse_r2v, or happyhorse_videoedit. All HappyHorse modes support 3-15 second clips, 720p or 1080p, and the Video Studio status workflow.

Core endpoints

POST /api/v1/video-studio/generate/

GET /api/v1/video-studio/status/{job_id}/

GET /api/v1/video-studio/history/

Pricing

720p: 31 credits per second

1080p: 53 credits per second

Minimum request: 3 seconds

Direct routes

Open HappyHorse composer

Compare video models

Buy credits

Mode-specific validation rules

Model slug Mode Duration Required input
happyhorse_t2v Text to video 3-15 seconds Prompt only. Reference media inputs are rejected.
happyhorse_i2v Image to video 3-15 seconds Requires input_image_urls. Up to two image URLs are accepted.
happyhorse_r2v Reference to video 3-15 seconds Requires input_image_urls. Up to nine reference images are accepted.
happyhorse_videoedit Video edit 3-15 seconds Requires at least one input_video_urls value.

Request snippets

Text to video

{
  "model_slug": "happyhorse_t2v",
  "prompt": "A miniature cardboard city wakes up at night as tiny lights turn on one by one",
  "duration_seconds": 5,
  "quality_mode": "1080p",
  "aspect_ratio": "16:9"
}

Image to video

{
  "model_slug": "happyhorse_i2v",
  "prompt": "Animate the reference into a premium cinematic product reveal with a slow push-in",
  "input_image_urls": ["https://media.ulazai.com/examples/product-reference.jpg"],
  "duration_seconds": 5,
  "quality_mode": "1080p",
  "aspect_ratio": "16:9"
}

Reference to video

{
  "model_slug": "happyhorse_r2v",
  "prompt": "Keep the same character identity and build a short cinematic action beat",
  "input_image_urls": ["https://media.ulazai.com/examples/character-reference.jpg"],
  "duration_seconds": 8,
  "quality_mode": "720p",
  "aspect_ratio": "9:16"
}

Video edit

{
  "model_slug": "happyhorse_videoedit",
  "prompt": "Regrade the source clip with brighter highlights and smooth commercial motion",
  "input_video_urls": ["https://media.ulazai.com/examples/source-video.mp4"],
  "duration_seconds": 8,
  "quality_mode": "720p"
}

Related docs

Canonical Video Studio API Video model matrix Video status workflows Video errors and limits