Veo 3.1 Fast Reference to Video

VIDEOFeaturedgoogle-veo-3-1-fast-reference

Veo 3.1 Fast Reference to Video is the speed-optimized reference-guided mode of Google’s Veo 3.1 video model. It accepts up to three reference images alongside a text prompt to maintain consistent characters, objects, and styles across shots, with faster turnaround and lower cost than the standard Veo 3.1 Reference model. Perfect for advertising, social media, and rapid prototyping that needs character-consistent video at up to 4K resolution.

POST

/v2/workspaces/{workspace_id}/base-models/google-veo-3-1-fast-reference/inferences

curl --request POST \
  --url https://api.app.layer.ai/api/v2/workspaces/:workspace_id/base-models/google-veo-3-1-fast-reference/inferences \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
  "prompt": "a knight standing in a snowy forest",
  "aspect_ratio": "LANDSCAPE_16_9_720p",
  "duration_seconds": 8,
  "generate_audio": false,
  "guidance_file_reference_image": [
    {
      "url": "<file_url>"
    }
  ]
}'

import requests

url = "https://api.app.layer.ai/api/v2/workspaces/:workspace_id/base-models/google-veo-3-1-fast-reference/inferences"

payload = {
    "prompt": "a knight standing in a snowy forest",
    "aspect_ratio": "LANDSCAPE_16_9_720p",
    "duration_seconds": 8,
    "generate_audio": False,
    "guidance_file_reference_image": [{ "url": "<file_url>" }]
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.json())

const url = 'https://api.app.layer.ai/api/v2/workspaces/:workspace_id/base-models/google-veo-3-1-fast-reference/inferences';
const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: '{"prompt":"a knight standing in a snowy forest","aspect_ratio":"LANDSCAPE_16_9_720p","duration_seconds":8,"generate_audio":false,"guidance_file_reference_image":[{"url":"<file_url>"}]}'
};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}

package main

import (
  "fmt"
  "strings"
  "net/http"
  "io"
)

func main() {

  url := "https://api.app.layer.ai/api/v2/workspaces/:workspace_id/base-models/google-veo-3-1-fast-reference/inferences"

  payload := strings.NewReader("{\n  \"prompt\": \"a knight standing in a snowy forest\",\n  \"aspect_ratio\": \"LANDSCAPE_16_9_720p\",\n  \"duration_seconds\": 8,\n  \"generate_audio\": false,\n  \"guidance_file_reference_image\": [\n    {\n      \"url\": \"<file_url>\"\n    }\n  ]\n}")

  req, _ := http.NewRequest("POST", url, payload)

  req.Header.Add("Authorization", "Bearer <token>")
  req.Header.Add("Content-Type", "application/json")

  res, _ := http.DefaultClient.Do(req)

  defer res.Body.Close()
  body, _ := io.ReadAll(res.Body)

  fmt.Println(res)
  fmt.Println(string(body))

}

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.app.layer.ai/api/v2/workspaces/:workspace_id/base-models/google-veo-3-1-fast-reference/inferences",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'prompt' => 'a knight standing in a snowy forest',
    'aspect_ratio' => 'LANDSCAPE_16_9_720p',
    'duration_seconds' => 8,
    'generate_audio' => null,
    'guidance_file_reference_image' => [
        [
                'url' => '<file_url>'
        ]
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

OkHttpClient client = new OkHttpClient();

MediaType mediaType = MediaType.parse("application/json");
RequestBody body = RequestBody.create(mediaType, "{\n  \"prompt\": \"a knight standing in a snowy forest\",\n  \"aspect_ratio\": \"LANDSCAPE_16_9_720p\",\n  \"duration_seconds\": 8,\n  \"generate_audio\": false,\n  \"guidance_file_reference_image\": [\n    {\n      \"url\": \"<file_url>\"\n    }\n  ]\n}");
Request request = new Request.Builder()
  .url("https://api.app.layer.ai/api/v2/workspaces/:workspace_id/base-models/google-veo-3-1-fast-reference/inferences")
  .post(body)
  .addHeader("Authorization", "Bearer <token>")
  .addHeader("Content-Type", "application/json")
  .build();

Response response = client.newCall(request).execute();

require 'uri'
require 'net/http'

url = URI("https://api.app.layer.ai/api/v2/workspaces/:workspace_id/base-models/google-veo-3-1-fast-reference/inferences")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"prompt\": \"a knight standing in a snowy forest\",\n  \"aspect_ratio\": \"LANDSCAPE_16_9_720p\",\n  \"duration_seconds\": 8,\n  \"generate_audio\": false,\n  \"guidance_file_reference_image\": [\n    {\n      \"url\": \"<file_url>\"\n    }\n  ]\n}"

response = http.request(request)
puts response.read_body

var client = new RestClient("https://api.app.layer.ai/api/v2/workspaces/:workspace_id/base-models/google-veo-3-1-fast-reference/inferences");
var request = new RestRequest("", Method.Post);
request.AddHeader("Authorization", "Bearer <token>");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"prompt\": \"a knight standing in a snowy forest\",\n  \"aspect_ratio\": \"LANDSCAPE_16_9_720p\",\n  \"duration_seconds\": 8,\n  \"generate_audio\": false,\n  \"guidance_file_reference_image\": [\n    {\n      \"url\": \"<file_url>\"\n    }\n  ]\n}", ParameterType.RequestBody);
var response = client.Execute(request);

Authorizations

bearerAuth

Parameters

Path Parameters

workspace_id

required

Workspace Id

Id of the workspace that owns the resource.

string format: uuid

Id of the workspace that owns the resource.

Query Parameters

session_name

Any of:

string
null

string

Organize this run under a named session. A new session is created if none matches.

Request Body^required

application/json

Veo 3.1 Fast Reference to Video

object

prompt

Prompt

string

aspect_ratio

Aspect Ratio

string

default: LANDSCAPE_16_9_720p

Allowed values: LANDSCAPE_16_9_720p PORTRAIT_9_16_720p LANDSCAPE_16_9_1080p PORTRAIT_9_16_1080p LANDSCAPE_16_9_2160p PORTRAIT_9_16_2160p

duration_seconds

Duration

integer

default: 8

generate_audio

Generate Audio

boolean

guidance_file_reference_image

Reference image

Guides style and content without being modified

Array<object>

InferenceFormFileRef

A single guidance/reference file supplied to a reference_image_list field.

The slot’s guidance type is fixed by the field it’s attached to; the caller supplies the file URL and, where the model supports per-file weighting, a weight.

object

url

required

Url

string

weight

Weight

number

nullable

prompt_language

Prompt Language

Advanced field.

string

nullable

Example

{
  "prompt": "a knight standing in a snowy forest",
  "aspect_ratio": "LANDSCAPE_16_9_720p",
  "duration_seconds": 8,
  "generate_audio": false,
  "guidance_file_reference_image": [
    {
      "url": "<file_url>"
    }
  ]
}

Responses

202

Successful Response

application/json

ExecuteForgeOutput

object

inference_id

required

Inference Id

Unique identifier for this forge run.

string format: uuid

status

required

InferenceStatus

Current status: IN_PROGRESS.

string

Allowed values: in_progress complete failed cancelled deleted

estimated_price_creative_units

Any of:

number
null

number

poll_interval_seconds

required

Poll Interval Seconds

Suggested polling interval in seconds.

integer

created_at

required

Created At

Timestamp of when the run was created.

string format: date-time

session_id

Any of:

string
null

string format: uuid

normalized_parameters

Any of:

NormalizedInferenceParameters
null

NormalizedInferenceParameters

Inference parameters after model-specific normalization.

These reflect the actual values used for generation, including model defaults applied for any parameters not explicitly set.

object

width

Any of:

integer
null

integer

height

Any of:

integer
null

integer

batch_size

Any of:

integer
null

integer

num_inference_steps

Any of:

integer
null

integer

guidance_scale

Any of:

number
null

number

duration_seconds

Any of:

number
null

number

fps

Any of:

integer
null

integer

Example

{
  "status": "in_progress"
}

401

Unauthenticated — missing or invalid Bearer token.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

403

Forbidden — insufficient permissions.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

404

Resource not found.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

422

Invalid input parameters.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

429

Rate limited — too many concurrent requests.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

500

Internal server error.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

Veo 3.1 Fast Reference to Video

Authorizations

Parameters

Path Parameters

Query Parameters

Request Bodyrequired

Example

Responses

202

Example

401

Example

403

Example

404

Example

422

Example

429

Example

500

Example

Request Body^required