Veo-3.1-Generate-Preview - Text To Video

POST

v1beta

models

veo-3.1-generate-preview:predictLongRunning

veo-3.1-generate-preview (Text To Video)

curl --request POST \
  --url https://gptproto.com/v1beta/models/veo-3.1-generate-preview:predictLongRunning

import requests

url = "https://gptproto.com/v1beta/models/veo-3.1-generate-preview:predictLongRunning"

response = requests.post(url)

print(response.text)

const options = {method: 'POST'};

fetch('https://gptproto.com/v1beta/models/veo-3.1-generate-preview:predictLongRunning', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://gptproto.com/v1beta/models/veo-3.1-generate-preview:predictLongRunning",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
]);

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

curl_close($curl);

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

package main

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

func main() {

	url := "https://gptproto.com/v1beta/models/veo-3.1-generate-preview:predictLongRunning"

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

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

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

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://gptproto.com/v1beta/models/veo-3.1-generate-preview:predictLongRunning")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://gptproto.com/v1beta/models/veo-3.1-generate-preview:predictLongRunning")

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

request = Net::HTTP::Post.new(url)

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

Authentication

Sign up for a GPTProto account at https://gptproto.com
Navigate to the API Keys section in your dashboard
Generate a new API key (sk-xxxxx)
Copy and securely store your API key For authentication details, please refer to the Authentication section.

Initiate Request

curl --location 'https://gptproto.com/v1beta/models/veo-3.1-generate-preview:predictLongRunning' \
--header 'x-goog-api-key: GPTPROTO_API_KEY' \
--header 'Content-Type: application/json' \
--data '{
  "instances": [
    {
      "prompt": "a cat"
    }
  ]
}'

const axios = require('axios');
let data = JSON.stringify({
  "instances": [
    {
      "prompt": "a cat"
    }
  ]
});

let config = {
  method: 'post',
  maxBodyLength: Infinity,
  url: 'https://gptproto.com/v1beta/models/veo-3.1-generate-preview:predictLongRunning',
  headers: { 
    'x-goog-api-key': 'GPTPROTO_API_KEY', 
    'Content-Type': 'application/json'
  },
  data : data
};

axios.request(config)
.then((response) => {
  console.log(JSON.stringify(response.data));
})
.catch((error) => {
  console.log(error);
});

import requests
import json

url = "https://gptproto.com/v1beta/models/veo-3.1-generate-preview:predictLongRunning"

payload = json.dumps({
  "instances": [
    {
      "prompt": "a cat"
    }
  ]
})
headers = {
  'x-goog-api-key': 'GPTPROTO_API_KEY',
  'Content-Type': 'application/json'
}

response = requests.request("POST", url, headers=headers, data=payload)

print(response.text)

package main

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

func main() {

  url := "https://gptproto.com/v1beta/models/veo-3.1-generate-preview:predictLongRunning"
  method := "POST"

  payload := strings.NewReader(`{
  "instances": [
    {
      "prompt": "a cat"
    }
  ]
}`)

  client := &http.Client {
  }
  req, err := http.NewRequest(method, url, payload)

  if err != nil {
    fmt.Println(err)
    return
  }
  req.Header.Add("x-goog-api-key", "GPTPROTO_API_KEY")
  req.Header.Add("Content-Type", "application/json")

  res, err := client.Do(req)
  if err != nil {
    fmt.Println(err)
    return
  }
  defer res.Body.Close()

  body, err := io.ReadAll(res.Body)
  if err != nil {
    fmt.Println(err)
    return
  }
  fmt.Println(string(body))
}

Query Result

After submitting a video generation request, the API returns an operation object. Use the operation name to poll for the result.

curl -X GET "https://api.gptproto.com/v1beta/models/{model}/operations/{operation_id}" \
  -H "x-goog-api-key: GPTPROTO_API_KEY" \
  -H "Content-Type: application/json"

import requests

url = "https://api.gptproto.com/v1beta/models/{model}/operations/{operation_id}"
headers = {
    "x-goog-api-key": "GPTPROTO_API_KEY",
    "Content-Type": "application/json"
}

response = requests.get(url, headers=headers)
result = response.json()
print(result)

const url = "https://api.gptproto.com/v1beta/models/{model}/operations/{operation_id}";
const headers = {
  "x-goog-api-key": "GPTPROTO_API_KEY",
  "Content-Type": "application/json"
};

fetch(url, { method: "GET", headers })
  .then(response => response.json())
  .then(data => console.log(data))
  .catch(error => console.error("Error:", error));

Query URL uses api.gptproto.com domain. Replace {model} with the model name and {operation_id} with the operation ID from the generation response.

Response Example

{
  "name": "models/veo-3.1-generate-preview/operations/abc123",
  "done": true,
  "response": {
    "generateVideoResponse": {
      "generatedSamples": [
        {
          "video": {
            "uri": "https://api.gptproto.com/upload/v1beta/files/abc:download?alt=media",
            "encoding": "video/mp4"
          }
        }
      ]
    }
  }
}

Download Video

Once the operation is complete, use the video URI from the response to download the generated video.

curl -L "https://api.gptproto.com/upload/v1beta/files/{file_id}:download?alt=media" \
  -H "x-goog-api-key: GPTPROTO_API_KEY" \
  -o output.mp4

import requests

url = "https://api.gptproto.com/upload/v1beta/files/{file_id}:download?alt=media"
headers = {
    "x-goog-api-key": "GPTPROTO_API_KEY"
}

response = requests.get(url, headers=headers)
with open("output.mp4", "wb") as f:
    f.write(response.content)
print("Video saved to output.mp4")

const url = "https://api.gptproto.com/upload/v1beta/files/{file_id}:download?alt=media";
const headers = {
  "x-goog-api-key": "GPTPROTO_API_KEY"
};

fetch(url, { headers })
  .then(response => response.blob())
  .then(blob => {
    const a = document.createElement("a");
    a.href = URL.createObjectURL(blob);
    a.download = "output.mp4";
    a.click();
  });

Replace {file_id} with the file ID from the video URI in the query response (e.g. abc from .../files/abc:download?alt=media).

Parameters

Path Parameters

Endpoint: https://gptproto.com/v1beta/models/{model}:predictLongRunning

Model	Description
`veo-3.1-generate-preview`	Veo 3.1 standard — highest quality
`veo-3.1-fast-generate-preview`	Veo 3.1 Fast — optimized for speed

Request Body

The request uses Google’s Vertex AI format with instances and parameters arrays.

instances[0] — Core Parameters

Parameter	Type	Required	Default	Description
`prompt`	string	✅ Yes	-	A text description of the desired video. Supports audio cues.
`image`	object	❌ No	-	Source image for image-to-video generation.
`image.mimeType`	string	❌ No	-	MIME type of the image (e.g. `image/png`, `image/jpeg`).
`image.bytesBase64Encoded`	string	❌ No	-	Base64-encoded image data.
`video`	object	❌ No	-	Source video for video-to-video generation (editing/extension).
`video.uri`	string	❌ No	-	URL of the source video.

parameters — Advanced Parameters

Parameter	Type	Required	Default	Range	Description
`aspectRatio`	string	❌ No	`16:9`	`16:9` `9:16`	The aspect ratio of the generated video.
`resolution`	string	❌ No	`720p`	`720p` `1080p` `4k`	The resolution of the generated video. `1080p` and `4k` only support 8s duration.
`durationSeconds`	string	❌ No	-	`4, 6, 8`	Length of the generated video in seconds. Must be `8` for 1080p/4k.
`personGeneration`	string	❌ No	-	`allow_all` `allow_adult`	Controls the generation of people.
`enhancePrompt`	boolean	❌ No	`true`	`true, false`	Whether to enhance the prompt for better quality.

Scene Comparison

Feature	text-to-video	image-to-video	video-to-video
`prompt`	✅ Required	✅ Required	✅ Required
`image`	❌	✅ Required	❌
`video`	❌	❌	✅ Required
`aspectRatio`	✅	✅	✅
`resolution`	✅	✅	✅
Audio cues in prompt	✅	✅	✅

Notes:

veo-3.1-generate-preview: Highest quality, suitable for professional content.
veo-3.1-fast-generate-preview: Lower latency, suitable for high-volume tasks.
Video retention: Generated videos are stored for 2 days.
Watermarking: Videos are watermarked using Google SynthID.

Error Codes

Common Error Codes

Error Code	Error Name	Description
401	Unauthorized	API key is missing or invalid
403	Forbidden	Your API key doesn’t have permission to access this resource, or insufficient balance for the requested operation
429	Too Many Requests	You’ve exceeded your rate limit
500	Internal server error	An internal server error occurred
503	Content policy violation	Content blocked due to safety concerns (actual status code is 400)

Veo-3.1-Generate-Preview - Image To Video

Veo-3.1-Generate-Preview - Video To Video

​Authentication

​Initiate Request

​Query Result

​Download Video

​Parameters

​Path Parameters

​Request Body

​instances[0] — Core Parameters

​parameters — Advanced Parameters

​Scene Comparison

​Error Codes

​Common Error Codes

Authentication

Initiate Request

Query Result

Download Video

Parameters

Path Parameters

Request Body

instances[0] — Core Parameters

parameters — Advanced Parameters

Scene Comparison

Error Codes

Common Error Codes