Video Generation

/v1/video/generations turns text prompts into video generation jobs through LLMTR. The endpoint starts long-running provider tasks, polls until completion, and returns video URLs in the OpenAI-compatible response shape.

Alibaba HappyHorse

HappyHorse generates videos from text through Alibaba. The model passed a live 5-second 720P verification test before public catalog activation.

curl "$LLMTR_BASE_URL/v1/video/generations" \
  -H "Authorization: Bearer llmtr-your_key" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "alibaba/happyhorse-1.0-t2v",
    "prompt": "A miniature city built from cardboard and bottle caps comes alive at night. A cardboard train rolls slowly by with tiny lights.",
    "duration_seconds": 5,
    "resolution": "720P",
    "aspect_ratio": "16:9",
    "max_wait_seconds": 180,
    "max_budget_usd": 0.70
  }'

Google Veo

Google Veo models use the same endpoint: google/veo-3.1-generate-001, google/veo-3.1-fast-generate-001, google/veo-3.1-lite-generate-001, google/veo-3.0-generate-001, google/veo-3.0-fast-generate-001, and google/veo-2.0-generate-001. Veo 3.x outputs include audio.

curl "$LLMTR_BASE_URL/v1/video/generations" \
  -H "Authorization: Bearer llmtr-your_key" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "google/veo-3.1-fast-generate-001",
    "prompt": "A cinematic drone shot over Cappadocia at sunrise",
    "duration_seconds": 8,
    "aspect_ratio": "16:9",
    "resolution": "720p",
    "max_wait_seconds": 180,
    "max_budget_usd": 1.00
  }'

Image-to-video with a reference frame

Veo models can generate video from a reference frame provided as a base64 data URL in the image_url field. Remote URLs are not supported; the data:image/...;base64,... form is required, and remote URLs return 400 unsupported_input.

curl "$LLMTR_BASE_URL/v1/video/generations" \
  -H "Authorization: Bearer llmtr-your_key" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "google/veo-3.1-fast-generate-001",
    "prompt": "The person smiles and looks around, subtle camera push-in.",
    "image_url": "data:image/png;base64,iVBORw0KGgo...",
    "duration_seconds": 4,
    "resolution": "720p",
    "max_wait_seconds": 180
  }'

Veo responses return the video as base64 MP4 in data[].b64_json; the url field is null for these models.

xAI Grok Imagine

xai/grok-imagine-video generates video from a text prompt. xai/grok-imagine-video-1.5 is image-to-video: a starting frame is required and the prompt describes the motion. Grok Imagine Video 1.5 also generates sound effects, ambience, and speech in the same pass. Supported durations are 1-15 seconds; resolutions are 480p, 720p, and 1080p (1080p only for image-to-video).

Pass the starting frame in image_url as a base64 data URL. Because the model is image-to-video only, a request without image_url returns 400 invalid_request; passing image_url to the text-to-video grok-imagine-video returns 400 unsupported_input.

curl "$LLMTR_BASE_URL/v1/video/generations" \
  -H "Authorization: Bearer llmtr-your_key" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "xai/grok-imagine-video-1.5",
    "prompt": "Slow cinematic push-in, embers drift, subtle camera movement",
    "image_url": "data:image/png;base64,iVBORw0KGgo...",
    "duration_seconds": 6,
    "resolution": "720p",
    "aspect_ratio": "16:9",
    "max_wait_seconds": 180,
    "max_budget_usd": 1.00
  }'

xAI responses return the video as a hosted data[].url MP4. Billing uses the real provider-reported cost when available; the per-second rate below is the reservation and fallback estimate.

Parameters

Field	Description
`model`	Canonical ID of the video generation model.
`prompt`	Text description of the video to generate.
`duration_seconds`	Generated video duration. Use a positive integer for HappyHorse. Veo supports 4-8 seconds. Grok Imagine supports 1-15 seconds.
`resolution`	`720P` or `1080P` for HappyHorse. `720p`, `1080p`, or `4k` for Veo (Veo 3.1 Lite does not support 4k). `480p`, `720p`, or `1080p` for Grok Imagine. Defaults to `720p`.
`aspect_ratio`	Ratio value. Defaults to `16:9`.
`negative_prompt`	Description of elements to avoid in the video (Veo and HappyHorse).
`image_url`	Image-to-video reference frame as a base64 data URL. Supported by Google Veo (all Veo models) and required by `xai/grok-imagine-video-1.5`.
`max_wait_seconds`	Timeout for the long-running job. Maximum 300 seconds.
`max_budget_usd`	Spend cap checked before the gateway starts the request.

Response

{
  "id": "task_xxx",
  "object": "video.generation",
  "model": "alibaba/happyhorse-1.0-t2v",
  "status": "completed",
  "data": [
    {
      "url": "/media/generated-video.mp4",
      "mime_type": "video/mp4",
      "duration": 5
    }
  ],
  "usage": {
    "duration": 5,
    "resolution": "720P"
  }
}

Pricing

Video models are billed per generated second; no platform margin is added to model pricing.

Model	720p	1080p	4k
`xai/grok-imagine-video`	$0.05/s	$0.05/s	-
`xai/grok-imagine-video-1.5`	$0.08/s	$0.08/s	-
`alibaba/happyhorse-1.0-t2v`	$0.14/s	$0.24/s	-
`google/veo-3.1-generate-001`	$0.40/s	$0.40/s	$0.60/s
`google/veo-3.1-fast-generate-001`	$0.10/s	$0.12/s	$0.30/s
`google/veo-3.1-lite-generate-001`	$0.05/s	$0.08/s	-
`google/veo-3.0-generate-001`	$0.40/s	$0.40/s	$0.40/s
`google/veo-3.0-fast-generate-001`	$0.10/s	$0.12/s	$0.30/s
`google/veo-2.0-generate-001`	$0.35/s	$0.35/s	-