LTX 2 19B Lipsync | AI Digital Human API

LTX-2 19B Lipsync

LTX-2 Lipsync is an audio-driven digital human model that generates synchronized talking head videos from a reference image and audio input. Powered by the 19B-parameter DiT (Diffusion Transformer) architecture, it produces high-fidelity lip-synced videos with natural head movements and expressions.

Why Choose This?

Audio-driven generation Simply provide an audio file and optional reference image — the model handles lip-sync, head motion, and expressions automatically.
High-fidelity output Leverages the 19B-parameter LTX-2 architecture for detailed, temporally consistent video with natural mouth movements.
Flexible resolution Supports 480p, 720p, and 1080p outputs to balance quality and cost.
Variable duration Video length is automatically determined by audio duration (5-20 seconds max).

Parameters

Parameter	Required	Description
audio	Yes	Audio file URL for lip-sync (determines video length)
image	No	Reference portrait image (JPG or PNG)
prompt	No	Optional text to guide generation style
resolution	No	Output resolution: 480p, 720p (default), or 1080p
seed	No	Random seed for reproducibility (-1 for random)

Resolution Options

Resolution	Best For
480p	Fast previews, iteration, lowest cost
720p	Balanced quality and cost (default)
1080p	Final delivery, maximum detail

How to Use

Upload your audio — the audio file that drives lip-sync and determines video duration.
Upload your image (optional) — the reference portrait that defines the speaker's appearance.
Write your prompt (optional) — describe any style or motion preferences.
Select resolution — 480p for iteration, 720p for balance, 1080p for final output.
Run — submit and download the lip-synced video.

Pricing

Resolution	5s	10s	15s	20s
480p	$0.075	$0.15	$0.225	$0.30
720p	$0.10	$0.20	$0.30	$0.40
1080p	$0.15	$0.30	$0.45	$0.60

Billing Rules

Base price: $0.10 (720p, 5 seconds)
Duration: Determined by audio length (min 5s, max 20s billing)
Resolution multiplier: 480p = 0.75×, 720p = 1×, 1080p = 1.5×
Total cost = duration × $0.10 × resolution_multiplier / 5

Best Use Cases

Digital Avatars — Create talking head videos for virtual presenters and avatars.
Content Creation — Generate lip-synced videos for social media and marketing.
Localization — Dub existing content with new audio while maintaining visual consistency.
Accessibility — Create sign language or narrated content with synchronized visuals.
Education — Produce instructional videos with talking head presenters.

Pro Tips

Use clear, high-quality audio for best lip-sync results.
Provide a front-facing portrait image with visible mouth for optimal generation.
Use high-quality, sharp, well-lit portrait images for best results.
Iterate at 480p to dial in results, then render at higher resolution for final output.
Use fixed seed when comparing variations to isolate changes.

Notes

Maximum video duration is 20 seconds (determined by audio length).
Audio longer than 20 seconds will be truncated.
The aspect ratio of output video is influenced by your input image.

Related Models

LTX-2 19B Image-to-Video — Animate images with synchronized audio from text prompts.
LTX-2 19B Text-to-Video — Generate video with audio from text only.
InfiniteTalk — Alternative audio-driven talking head generation.

Ltx 2 19b Lipsync API — Quick start

Grab a WaveSpeedAI API key, then call POST https://api.wavespeed.ai/api/v3/wavespeed-ai/ltx-2-19b/lipsync with your input as JSON. The endpoint returns a prediction id; poll the prediction endpoint until status flips to completed, then read the output URL from data.outputs[0]. Examples for Ltx 2 19b Lipsync below.

HTTP example

# Submit the prediction
curl -X POST "https://api.wavespeed.ai/api/v3/wavespeed-ai/ltx-2-19b/lipsync" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $WAVESPEED_API_KEY" \
  -d '{
    "audio": "https://example.com/your-audio.mp3",
    "image": "https://example.com/your-input.jpg",
    "prompt": "A cinematic shot of a city at sunset, soft golden light",
    "resolution": "720p",
    "seed": -1
}'

# Response includes a prediction id. Poll for the result:
curl -X GET "https://api.wavespeed.ai/api/v3/predictions/{request_id}/result" \
  -H "Authorization: Bearer $WAVESPEED_API_KEY"

# When status is "completed", read the output from data.outputs[0].

Node.js example

// npm install wavespeed
const WaveSpeed = require('wavespeed');

const client = new WaveSpeed(); // reads WAVESPEED_API_KEY from env

const result = await client.run("wavespeed-ai/ltx-2-19b/lipsync", {
        "audio": "https://example.com/your-audio.mp3",
        "image": "https://example.com/your-input.jpg",
        "prompt": "A cinematic shot of a city at sunset, soft golden light",
        "resolution": "720p",
        "seed": -1
});

console.log(result.outputs[0]); // → URL of the generated output

Python example

# pip install wavespeed
import wavespeed

output = wavespeed.run(
    "wavespeed-ai/ltx-2-19b/lipsync",
    {
    "audio": "https://example.com/your-audio.mp3",
    "image": "https://example.com/your-input.jpg",
    "prompt": "A cinematic shot of a city at sunset, soft golden light",
    "resolution": "720p",
    "seed": -1
}
)

print(output["outputs"][0])  # → URL of the generated output

Ltx 2 19b Lipsync API — Frequently asked questions

What is the Ltx 2 19b Lipsync API?

Ltx 2 19b Lipsync is a WaveSpeedAI model for talking-avatar generation, exposed as a REST API on WaveSpeedAI. LTX-2 Lipsync generates synchronized talking head videos from a reference image and audio input. Powered by the 19B DiT architecture, it produces high-fidelity lip-synced videos with natural head movements. Ready-to-use REST inference API, best performance, no coldstarts, affordable pricing. You can call it programmatically or try it from the playground above.

How do I call the Ltx 2 19b Lipsync API?

POST your input parameters to the model's REST endpoint (shown in the API tab of this playground) with your WaveSpeedAI API key in the Authorization header. Submission returns a prediction ID; poll the prediction endpoint until status flips to "completed", then read the output URL from the result. The playground generates a ready-to-paste code sample in Python, JavaScript, or cURL for whatever inputs you've set. Full request/response shape is documented at https://wavespeed.ai/docs/docs-api/wavespeed-ai/ltx-2-19b-lipsync.

How much does Ltx 2 19b Lipsync cost per run?

Ltx 2 19b Lipsync starts at $0.10 per run. That figure is the base price — the final charge scales with the parameters you set in the form (output size, length, count, references, or whatever knobs this model exposes), so a higher-quality or larger output costs more than a minimal one. The exact cost for your current input is shown live next to the Generate button before you submit, and the actual per-call charge is recorded on the prediction afterwards.

What inputs does Ltx 2 19b Lipsync accept?

Key inputs: `prompt`, `image`, `audio`, `resolution`, `seed`. The full JSON schema (types, defaults, allowed values) is rendered above the Generate button and mirrored in the API reference at https://wavespeed.ai/docs/docs-api/wavespeed-ai/ltx-2-19b-lipsync.

How long does Ltx 2 19b Lipsync take to generate?

Average end-to-end generation time on WaveSpeedAI is around 87 seconds per request — measured across recent runs. Queue time scales with global demand; live status is visible in the prediction record.

Can I use Ltx 2 19b Lipsync outputs commercially?

Commercial usage rights depend on the model's license, set by its provider (WaveSpeedAI). The license summary appears on the model card above; see WaveSpeedAI's Terms of Service for platform-level conditions.

ExamplesView all

Related Models

README

LTX-2 19B Lipsync

Why Choose This?

Parameters

Resolution Options

How to Use

Pricing

Billing Rules

Best Use Cases

Pro Tips

Notes

Related Models

Ltx 2 19b Lipsync API — Quick start

Ltx 2 19b Lipsync API — Frequently asked questions