V Express Serverless API

V-Express lets you create portrait videos from single images.

~196.29s
POST /v2/v-express · submit + poll
 1# pip install "segmind>=1.1.0"
 2# export SEGMIND_API_KEY="YOUR_API_KEY"
 3from segmind import SegmindClient, InferenceFailed, InferenceTimeout
 4
 5# Async (v2) — recommended for long-running / video models.
 6# run() blocks up to 600s; submit_async + job.wait(timeout=...) sets a longer
 7# deadline and keeps the request_id so you can re-poll later.
 8client = SegmindClient()                      # reads SEGMIND_API_KEY
 9payload = {
10    "input_image": "https://segmind-sd-models.s3.amazonaws.com/display_images/v_express/v-express-ip.jpg",
11    "input_audio": "https://segmind-sd-models.s3.amazonaws.com/display_images/v_express/v_express_audio.mp3",
12    "fps": 30,
13    "num_inference_steps": 20,
14    "guidance_scale": 2,
15    "retarget_strategy": "fix_face",
16    "base64": False,
17}
18job = client.submit_async("v-express", **payload)
19print(job.request_id)                         # available immediately
20try:
21    result = job.wait(timeout=900, interval=2.0)
22    print(result["status"])                  # COMPLETED
23    print(result.get("output"))              # model output (e.g. video URL)
24except InferenceTimeout as e:
25    print("still running:", e.request_id)    # re-poll later with this id
26except InferenceFailed as e:
27    print("failed:", e.detail)
28
29# Fast models (<=600s) can use the one-liner instead:
30# result = segmind.run("v-express", **payload)

API Endpoint

POSThttps://api.segmind.com/v1/v-express

Parameters

input_audiorequired
string (uri)

Input audio file. Avoid special symbol in the filename as it may cause ffmpeg erros.

input_imagerequired
string (uri)

Input image of a talking-head.

Default: "https://segmind-sd-models.s3.amazonaws.com/display_images/v_express/v-express-ip.jpg"
base64optional
boolean

Base64 encoding of the output image.

Default: false
fpsoptional
integer

Output frames per second.

Default: 30Range: 10 - 60
guidance_scaleoptional
integer

Scale for classifier-free guidance

Default: 2Range: 1 - 15
num_inference_stepsoptional
integer

Number of steps to generate.

Default: 20Range: 5 - 50
retarget_strategyoptional
string

Retarget Strategy.

Default: "fix_face"
Allowed values :
"fix_face""no_retarget""offset_retarget""naive_retarget"

Response Type

Returns: Video

Asynchronous requests (v2)

Use Async for video, long-running (>~60s), or high-concurrency workloads; Sync is simplest for fast image & LLM calls. Async submits a request and you poll it to completion.

  1. 1
    POST /v2/v-express

    Submitreturns request_id, status_url, response_url

  2. 2
    GET /v2/requests/{id}/status

    Polluntil COMPLETED or FAILED

  3. 3
    GET /v2/requests/{id}

    Resultfinal response body

Status states

QUEUEDAccepted, waiting for a worker
PROCESSINGRunning on a worker
COMPLETEDDone — result body is ready
FAILEDErrored (incl. content/RAI blocks)
  • A FAILED request is served as HTTP 422 — the body still carries the error detail.
  • An unknown or expired request_id returns HTTP 404.
  • Results are retained for 1 hour, then expire.
  • Content / RAI blocks surface as FAILED, not a separate state.
  • Track completion by polling the status endpoint.

Common Error Codes

The API returns standard HTTP status codes. Detailed error messages are provided in the response body.

400

Bad Request

Invalid parameters or request format

401

Unauthorized

Missing or invalid API key

403

Forbidden

Insufficient permissions

404

Not Found

Model or endpoint not found

406

Insufficient Credits

Not enough credits to process request

429

Rate Limited

Too many requests

500

Server Error

Internal server error

502

Bad Gateway

Service temporarily unavailable

504

Timeout

Request timed out