“Extreme cinematic close-up of a beautiful young woman experiencing deep, raw emotion. Her expression slowly shifts from quiet sorrow to intense cathartic crying — realistic skin texture with visible pores, subtle muscle twitches, glistening tears forming in her eyes and rolling down her cheeks, red-rimmed eyes with natural blinking and micro-expressions of pain and release. Soft dramatic side lighting with gentle rim light highlighting the tears, very shallow depth of field, slight emotional camera push-in during the emotional peak, photorealistic, 8K, intricate skin and eye details, filmic color grading, subtle film grain.”
Google's fast video generation model producing 720p/1080p video up to 8 seconds with optional native audio including synchronized sound effects, ambient noise, and dialogue with lip-sync
Details
veo-3.1-fast
Starting from
Prices shown are in USD
Full pricing detailsProviders & Pricing (1)
Veo 3.1 Fast is available exclusively through Google Gemini API, starting at $0.1/video.
All modes
gemini/veo-3.1-fast
Output
veo-3-1-fast API Async video generation
https://api.lumenfall.ai/v1
veo-3.1-fast
Code Examples
Text to Video
/v1/videos/generations# Step 1: Submit video generation request
VIDEO_ID=$(curl -s -X POST \
https://api.lumenfall.ai/v1/videos \
-H "Authorization: Bearer $LUMENFALL_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "veo-3.1-fast",
"prompt": "",
"size": "1024x1024"
}' | jq -r '.id')
echo "Video ID: $VIDEO_ID"
# Step 2: Poll for completion
while true; do
RESULT=$(curl -s \
https://api.lumenfall.ai/v1/videos/$VIDEO_ID \
-H "Authorization: Bearer $LUMENFALL_API_KEY")
STATUS=$(echo $RESULT | jq -r '.status')
echo "Status: $STATUS"
if [ "$STATUS" = "completed" ]; then
echo $RESULT | jq -r '.output.url'
break
elif [ "$STATUS" = "failed" ]; then
echo $RESULT | jq -r '.error.message'
break
fi
sleep 5
done
const BASE_URL = 'https://api.lumenfall.ai/v1';
const API_KEY = 'YOUR_API_KEY';
// Step 1: Submit video generation request
const submitRes = await fetch(`${BASE_URL}/videos`, {
method: 'POST',
headers: {
'Authorization': `Bearer ${API_KEY}`,
'Content-Type': 'application/json'
},
body: JSON.stringify({
model: 'veo-3.1-fast',
prompt: '',
size: '1024x1024'
})
});
const { id: videoId } = await submitRes.json();
console.log('Video ID:', videoId);
// Step 2: Poll for completion
while (true) {
const pollRes = await fetch(`${BASE_URL}/videos/${videoId}`, {
headers: { 'Authorization': `Bearer ${API_KEY}` }
});
const result = await pollRes.json();
if (result.status === 'completed') {
console.log('Video URL:', result.output.url);
break;
} else if (result.status === 'failed') {
console.error('Error:', result.error.message);
break;
}
await new Promise(r => setTimeout(r, 5000));
}
import requests
import time
BASE_URL = "https://api.lumenfall.ai/v1"
API_KEY = "YOUR_API_KEY"
HEADERS = {
"Authorization": f"Bearer {API_KEY}",
"Content-Type": "application/json"
}
# Step 1: Submit video generation request
response = requests.post(
f"{BASE_URL}/videos",
headers=HEADERS,
json={
"model": "veo-3.1-fast",
"prompt": "",
"size": "1024x1024"
}
)
video_id = response.json()["id"]
print(f"Video ID: {video_id}")
# Step 2: Poll for completion
while True:
result = requests.get(
f"{BASE_URL}/videos/{video_id}",
headers=HEADERS
).json()
if result["status"] == "completed":
print(f"Video URL: {result['output']['url']}")
break
elif result["status"] == "failed":
print(f"Error: {result['error']['message']}")
break
time.sleep(5)
Image to Video
/v1/videos/generationsParameter Reference
Core Parameters
| Parameter | Type | Description | Modes |
|---|---|---|---|
prompt
|
string | Required. Text prompt for video generation |
T2V
I2V
|
negative_prompt
|
string | Negative prompt to guide generation away from undesired content |
T2V
I2V
|
duration
|
number | Video duration in seconds |
T2V
I2V
|
Size & Layout
| Parameter | Type | Description | Modes |
|---|---|---|---|
size
|
string |
Video dimensions as WxH pixels (e.g. "1920x1080") or aspect ratio (e.g. "16:9")
1365x768
768x1365
WxH determines both shape and scale (aspect_ratio and resolution are ignored when size is provided). W:H format is equivalent to aspect_ratio.
|
T2V
I2V
|
aspect_ratio
|
string |
Aspect ratio of the output video (e.g. "16:9", "1:1")
9:16
16:9
Controls shape independently of scale. Use with resolution to control both. If size is also provided, size takes precedence. Any ratio is accepted and mapped to the nearest supported value.
|
T2V
I2V
|
resolution
|
string |
Output resolution tier (e.g. "1K", "4K")
1K
Controls scale independently of shape. Higher tiers produce larger videos and cost more. If size is also provided, size takes precedence for scale. Any tier is accepted and mapped to the nearest supported value.
|
T2V
I2V
|
1K 2 sizes
| Output |
size
|
aspect_ratio
+
resolution
|
|
|---|---|---|---|
| 768 × 1365 | "768x1365" |
or |
"9:16"
+
"1K"
|
| 1365 × 768 | "1365x768" |
or |
"16:9"
+
"1K"
|
How these parameters work
size
Exact pixel dimensions
"1920x1080"
aspect_ratio
Shape only, default scale
"16:9"
resolution
Scale tier, preserves shape
"1K"
Priority when combined
size is most specific and always wins. aspect_ratio and resolution control shape and scale independently.
How matching works
7:1 on a model with
4:1 and 8:1,
you get 8:1.
0.5K 1K 2K 4K)
or megapixel tiers (0.25 1).
If the exact tier isn't available, you get the nearest one.
Media Inputs
| Parameter | Type | Description | Modes |
|---|---|---|---|
input_reference
|
array | Required. Input image(s) to animate into video |
T2V
I2V
|
Audio
| Parameter | Type | Description | Modes |
|---|---|---|---|
generate_audio
|
boolean | Whether to generate audio alongside video |
T2V
I2V
|
Output & Format
| Parameter | Type | Description | Modes |
|---|---|---|---|
n
|
integer |
Number of videos to generate
Default:
1Gateway generates multiple videos in parallel even if provider only supports 1.
|
T2V
I2V
|
Parameter Normalization
How we handle parameters across different providers
Not every provider speaks the same language. When you send a parameter, we handle it in one of four ways depending on what the model supports:
| Behavior | What happens | Example |
|---|---|---|
passthrough |
Sent as-is to the provider | style, quality |
renamed |
Same value, mapped to the field name the provider expects | prompt |
converted |
Transformed to the provider's native format | size |
emulated |
Works even if the provider has no concept of it | n, response_format |
Parameters we don't recognize pass straight through to the upstream API, so provider-specific options still work.
Veo 3.1 Fast Benchmarks
Veo 3.1 Fast is ranked #2 in Text-to-Video with an Elo of 1124 on the Lumenfall Arena, where real users pick the better image in blind comparisons. These rankings are based on 2 blind-vote competitions.
Text-to-Video Landscape
Elo vs Cost
Elo vs Speed
Competition Results
Uncategorized
“Hyper-realistic cinematic close-up of a professional speedcuber solving a 3x3 Rubik's Cube at world-record pace. His hands move with insane precision and blistering speed — fingers flying across the glossy colored faces in a complex sequence of advanced algorithms, rapid twists, and smooth layer turns. The cube rotates with perfect realistic physics, slight motion blur on fast turns, and flawless color consistency as it progresses toward a solved state. Subtle sweat glistening on skin, visible veins, hyper-detailed fingerprints and nail textures. Intense focused facial expression with micro-expressions of concentration in shallow depth of field. Dramatic cinematic side lighting with strong specular highlights and reflections dancing across the cube surfaces and skin. Smooth slow orbiting camera that circles the hands and cube, capturing every intricate finger movement from dynamic angles. Photorealistic, 8K, subtle film grain, anamorphic lens flare, moody intense atmosphere, 24fps.”
Veo 3.1 Fast FAQ
How much does Veo 3.1 Fast cost?
Veo 3.1 Fast starts at $0.1 per video through Lumenfall. Pricing varies by provider. Lumenfall does not add any markup to provider pricing.
How do I use Veo 3.1 Fast via API?
You can use Veo 3.1 Fast through Lumenfall's OpenAI-compatible API. Send requests to the unified endpoint with model ID "veo-3.1-fast". Code examples are available in Python, JavaScript, and cURL.
Which providers offer Veo 3.1 Fast?
Veo 3.1 Fast is available through Google Gemini API on Lumenfall. Lumenfall automatically routes requests to the best available provider.
Try Veo 3.1 Fast in Playground
Generate images with custom prompts — no API key needed.