Veo 3.1 API

Veo 3.1 on Buble is available as Fast and Quality variants for cinematic text-to-video, reference-to-video, and frame-controlled video generation.

Model keys

google/veo3.1-fast — Veo3.1 Fast
google/veo3.1-quality — Veo3.1 Quality

Supported modes and inputs

Model	Mode	Label	Input requirements
`google/veo3.1-fast`	`text_to_video`	Text to Video	Prompt max 2000 chars
`google/veo3.1-fast`	`reference_to_video`	Reference to Video	Prompt max 2000 chars Images `reference`: 1-3 files, 10 MB, formats jpg, png, webp
`google/veo3.1-fast`	`frames_to_video`	Frames to Video	Prompt max 2000 chars Images `start_frame,end_frame`: 1-2 files, 10 MB, formats jpg, png, webp
`google/veo3.1-quality`	`text_to_video`	Text to Video	Prompt max 2000 chars
`google/veo3.1-quality`	`reference_to_video`	Reference to Video	Prompt max 2000 chars Images `reference`: 1-3 files, 10 MB, formats jpg, png, webp
`google/veo3.1-quality`	`frames_to_video`	Frames to Video	Prompt max 2000 chars Images `start_frame,end_frame`: 1-2 files, 10 MB, formats jpg, png, webp

Options

Model	Option	Default	Allowed values	Applies to
`google/veo3.1-fast`	`duration`	`8s`	`8s`	All modes
`google/veo3.1-fast`	`resolution`	`720p`	`720p`, `1080p`, `4k`	All modes
`google/veo3.1-fast`	`aspect_ratio`	`16:9`	`16:9`, `9:16`	All modes
`google/veo3.1-quality`	`duration`	`8s`	`8s`	All modes
`google/veo3.1-quality`	`resolution`	`720p`	`720p`, `1080p`, `4k`	All modes
`google/veo3.1-quality`	`aspect_ratio`	`16:9`	`16:9`, `9:16`	All modes

Pricing

Model	Pricing
`google/veo3.1-fast`	5 credits per second; option multipliers: `resolution`=`{"4k":3,"720p":1,"1080p":1}`
`google/veo3.1-quality`	1 credit per second; option multipliers: `resolution`=`{"4k":80,"720p":26,"1080p":26}`

Production guidance

Pass mode explicitly.
Use only option values listed above.
Upload media with POST /api/v1/files before calling media-input modes.
Use the exact model key for the variant you want.

Example: text to video

curl https://buble.ai/api/v1/generations \
  -H "Authorization: Bearer $BUBLE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "google/veo3.1-fast",
    "mode": "text_to_video",
    "prompt": "A cinematic product launch shot with slow camera movement, premium lighting, and realistic motion",
    "duration": "8s",
    "resolution": "720p",
    "aspect_ratio": "16:9"
  }'

Example: media-guided video

curl https://buble.ai/api/v1/generations \
  -H "Authorization: Bearer $BUBLE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "google/veo3.1-fast",
    "mode": "frames_to_video",
    "prompt": "Animate the source into a polished cinematic motion shot with natural camera movement",
    "start_frame": "https://example.com/start.png",
    "duration": "8s",
    "resolution": "720p",
    "aspect_ratio": "16:9"
  }'

Veo 3.1 API

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