Openspline

Open source alternative to HeyGen LiveAvatar, Tavus, Simli, Beyond Presence, HeyGen and D-ID

261 stars
MIT
Active this week
Last commit 1 day ago

Last verified Oct 21, 2026

Build synchronized talking-avatar video into voice AI agents using Python or Node, MIT-licensed and self-hosted on NVIDIA GPUs or Openspline Cloud.

Visit website GitHub261 Deploy on Hostinger

Read the full breakdownWho it is for, how it works, trade-offs, the quick start and the FAQ

who it's for

Who Openspline is for#

AI engineers adding avatar output to an existing voice agent

Openspline connects to running OpenAI Realtime, LiveKit, Gemini Live, or ElevenLabs sessions via a provider-specific connector. The agent keeps its existing voice, tools, and prompts; Openspline intercepts the audio and returns a viewer URL for the synchronized video. No changes to the upstream agent architecture are required.

Skip if:

Your agent uses a voice provider without a built-in connector and your team cannot implement a custom async PCM audio iterator. The custom connector path requires hands-on understanding of async audio streaming.

Teams building face-to-face AI customer support or onboarding agents

A portrait image plus an existing support voice agent is enough to run a live-avatar customer interaction. Openspline Cloud handles GPU infrastructure, reducing setup to creating an avatar in the browser dashboard and embedding the viewer URL. The website shows a working support demo (Meera).

Skip if:

Your support deployment runs on a CPU-only server and your team cannot manage a separate GPU service or use Openspline Cloud.

Developers building AI tutors, coaches, or interview practice tools

The project demos include a tutoring avatar (Professor Nikolaev) and an interview practice partner (Lisa). These use cases benefit from a face-to-face feel. Openspline adds the avatar layer without requiring a video production setup or a separate streaming infrastructure.

Skip if:

Your tutoring product serves learners in bandwidth-constrained environments where sustained real-time WebRTC video streams are unreliable.

Privacy-conscious deployments needing on-premises avatar inference

Managed avatar APIs like HeyGen and D-ID process audio and generate video on their servers. Openspline's self-hosted path keeps all audio and video generation on the developer's own infrastructure, useful for healthcare, legal, or enterprise deployments with data residency or audit requirements.

Skip if:

Your infrastructure does not include an NVIDIA GPU and you cannot provision one. Without qualifying GPU hardware, the only option is Openspline Cloud, which processes data remotely.

the problem

The problem it solves#

Voice AI agents built on OpenAI Realtime, LiveKit, Gemini Live, or ElevenLabs respond naturally, but they appear as nothing more than a chat bubble or an audio waveform. Adding a face to a conversational agent requires a lip-sync inference model, a real-time streaming server, a WebRTC player, and connectors for every voice provider in use. Most development teams either skip the avatar entirely or pay a per-session fee to a managed API like HeyGen or Tavus, accepting vendor lock-in and per-minute costs that grow with usage.

The harder part is integration: managed avatar APIs own the audio playback path, which means wrapping them around an existing voice agent often duplicates the speaker output and breaks interruption handling. Teams end up rewriting parts of their agent architecture just to add a face to a conversation.

how Openspline solves it

How it solves it#

Five-line SDK integration

Pass a portrait image and your agent's PCM audio to the Openspline server; it returns a synchronized talking-head video URL in real time. Python and Node.js SDKs wrap the protocol with async context managers. No changes to existing prompts, tools, or voice providers are required.

Native connectors for major voice providers

Pre-built adapters for OpenAI Realtime, LiveKit Agents, Gemini Live, ElevenLabs Agents, Pipecat, Google ADK, and OpenAI Agents. Each connector intercepts audio from the existing session without replacing the playback path. Credentials stay on the developer's backend; Openspline receives only the audio stream.

Self-hosted GPU inference

Runs on any NVIDIA GPU under Linux or WSL2. The installer downloads Low and High quality inference models and configures GPU workers via a YAML file. A100 benchmarks from the README show approximately 64 FPS for low quality. Multiple workers can be assigned to separate GPU devices for concurrent sessions.

Embeddable player and React component

Every avatar session returns a viewer URL that embeds in any web page or native app. A React component and web component are included, so the frontend requires no custom WebRTC code. Only the avatar.session token goes to the browser; the full API key stays server-side.

Interruption handling and continuous idle motion

The SDK handles barge-in interruptions, turn-end events, and continuous idle motion between turns. ElevenLabs and OpenAI Realtime connectors pass interruption events through to existing handlers, preserving transcripts and tool call events. Float32 and encoded MP3 audio are supported in addition to PCM16.

Custom photo or video backgrounds

Avatar sessions support custom photo or video backgrounds, configurable per session via the SDK. Quality can be overridden per session (low or high), with high quality using more VRAM. JSON Schema configuration covers Python, Node.js, and the GPU worker, with typed config objects in both SDKs.

strengths · trade-offs

Strengths and trade-offs#

Strengths

MIT license with no per-session feesThe self-hosted SDK and server are MIT licensed. Unlike HeyGen or Tavus, which charge per minute of avatar output, a self-hosted Openspline deployment pays only for the GPU compute it runs on. Commercial use, modification, and redistribution are unrestricted.
Provider-agnostic: keeps the existing voice stackOpenspline adds avatar video without replacing the voice provider. Existing tools, prompts, function calls, and transcripts continue to reach existing handlers unchanged. Managed avatar APIs like HeyGen own the full audio pipeline; Openspline intercepts only the audio output.
Local-first inferenceAvatar generation runs on the developer's own GPU when self-hosted. Audio and video never leave the local network, which matters for deployments with data residency requirements. The cloud option is available for teams without GPUs, but the full pipeline runs offline.

Trade-offs

-NVIDIA GPU required for self-hostingSelf-hosting requires an NVIDIA GPU on Linux or WSL2. AMD and Apple Silicon are not yet supported. Pre-Ampere NVIDIA cards run inference in FP32 rather than FP16, which increases VRAM usage and may reduce throughput. Teams without a qualifying GPU must use Openspline Cloud.
-One session per GPU workerEach configured GPU worker serves one avatar session at a time. Concurrent sessions require one worker per session, meaning multiple GPU devices or separate worker processes. A CapacityError is returned when all workers are busy. The README notes that multi-GPU validation is still incomplete.
-Early-stage project with incomplete validationOpenspline was created in September 2026. The README explicitly states that long-duration, multi-GPU, cloud-provider, and TEN runtime validation are incomplete. High-quality mode benchmarks at approximately 8 FPS on an A100 under test conditions, which may not meet real-time requirements for all deployments. Teams should run load tests before relying on it in production.

versus alternatives

Openspline vs alternatives#

Openspline vs HeyGen

HeyGen and Openspline both generate synchronized talking-avatar video from a portrait image and audio. The primary difference is deployment model: HeyGen is a managed API with per-minute pricing; Openspline is open source and runs on developer-owned GPU hardware.

Feature	Openspline	HeyGen
License	MIT	Proprietary
Self-hosting	Yes (NVIDIA GPU)	No
Real-time streaming	Yes (WebRTC)	Yes
SDK	Python, Node.js	REST API
Pricing	Free (self-hosted)	Per-minute API fees

Openspline is the stronger choice when data privacy matters, when per-session costs would be prohibitive at scale, or when a team's voice agent runs on OpenAI Realtime or LiveKit and switching the audio playback path would require significant rework. HeyGen is the better option when no GPU hardware is available and a managed service with enterprise support is needed.

Openspline vs Tavus

Tavus focuses on personalized video at scale, with products oriented toward asynchronous video creation and conversational replicas. Openspline focuses on real-time, synchronous streaming into live voice agent sessions.

Feature	Openspline	Tavus
License	MIT	Proprietary
Self-hosting	Yes (NVIDIA GPU)	No
Primary use case	Live voice agents	Async and live video
Pricing	Free (self-hosted)	Subscription-based

Openspline is the better choice for developers who already have a voice AI pipeline and want to add synchronized video output without adopting a second vendor's audio infrastructure. Tavus is better suited for teams building personalized asynchronous video campaigns or replica-based interactions where managed infrastructure and a broader feature set justify the cost.

Openspline vs D-ID

D-ID is a commercial talking-head API serving use cases from marketing video generation to interactive avatars. It has no self-hosted deployment option.

Feature	Openspline	D-ID
License	MIT	Proprietary
Self-hosting	Yes (NVIDIA GPU)	No
Real-time streaming	Yes	Yes (via API)
Pricing	Free (self-hosted)	Per-credit pricing

D-ID is the better fit for non-technical buyers who need polished avatar video with no infrastructure management. Openspline suits developers who need to run inference on their own hardware, integrate tightly with existing voice AI code, or avoid per-credit costs for high-volume real-time sessions.

install · quick start

Quick start#

bash

Self-hosting installs the GPU inference server, then the Python or Node SDK.
```bash
curl -fsSL https://raw.githubusercontent.com/openspline/openspline/main/install.sh | sh
pip install openspline
npm install @openspline/node
```

tech stack · detected from GitHub

What it's built on#

Languages: JavaScriptPythonTypeScript
Tooling: esbuild

frequently asked

FAQ#

Does Openspline work with any voice AI framework, or only specific providers?

Native connectors are available for OpenAI Realtime, LiveKit Agents, Gemini Live, ElevenLabs Agents, Pipecat, Google ADK, OpenAI Agents, Vocode, and TEN. A custom connector path supports any provider with an async PCM audio iterator, covering TTS providers and agents not in the built-in list. Node.js exports match the Python connector surface.

What GPU hardware is required to self-host Openspline?

Self-hosting requires an NVIDIA GPU on Linux or WSL2. AMD and Apple Silicon are not yet supported. Pre-Ampere NVIDIA cards run inference in FP32, which uses more VRAM and may be slower. The README notes that Blackwell and pre-Ampere inference still need hardware validation. For teams without a qualifying GPU, Openspline Cloud is the alternative.

How does Openspline compare to HeyGen or Tavus for talking-avatar generation?

HeyGen and Tavus are managed cloud APIs that charge per minute of video and own the audio playback pipeline; Openspline is MIT-licensed and runs on your own GPU with no per-session fees. The tradeoff is infrastructure: Openspline requires an NVIDIA GPU for self-hosting, while HeyGen and Tavus require no hardware setup.

Can Openspline be used without a GPU?

Yes. Openspline Cloud provides the same SDK surface without local GPU hardware. Avatars can be created and embedded from the browser dashboard. The self-hosted free path requires NVIDIA GPU hardware on Linux or WSL2.

Is Openspline ready for production use?

The project was created in September 2026 and is under active development. The README explicitly notes that long-duration, multi-GPU, cloud-provider, and TEN runtime validation are incomplete. Low-quality inference has been exercised on real hardware with A100 benchmarks published. Teams should run their own load tests before production deployment.

also worth a look

Similar open-source tools#

OpenCreator

Alternative toHeyGen

Local AI workspace for video, image, voice, and translation

13,637 GitHub stars
Licence Apache-2.0

video-use

Alternative toDescript

Edit videos by chatting with Claude Code, not clicking menus

29,418 GitHub stars
Licence MIT

MoneyPrinterTurbo

Alternative toInVideo AI

AI-powered short video generation from topic to publish

133,408 GitHub stars
Licence MIT

stt

Alternative toMacWhisper

Local speech-to-text with multi-format output and GPU acceleration

4,823 GitHub stars
Licence GPL-3.0

YouDub-webui

Alternative toRask AI

Self-hosted AI video dubbing: YouTube to Chinese, Bilibili to English

5,703 GitHub stars
Licence Apache-2.0

pyvideotrans

Alternative toRask AI

Open source video translation with AI dubbing and voice cloning

19,477 GitHub stars
Licence GPL-3.0

by category

Open source tools in these categories#

404

Run Openspline on your own server

Self-host Openspline on a Hostinger VPS.

Deploy on Hostinger

Featured

rakazo

Alternative toGrok Bot

AI teammates you own: your keys, your model, your machine.

4,904 GitHub stars
Licence Apache-2.0
#AI Agents

Omnara

Alternative toClaude Managed Agents

Open-source agent deployment API. Self-host or use Omnara Cloud.

2,957 GitHub stars
Licence Apache-2.0
#AI Agents

Inbox Zero

Alternative toSuperhuman

AI email assistant that drafts replies and clears your inbox

12,712 GitHub stars
Licence AGPL-3.0
#Email

Feature your project

The projects we add and every new guide. Free, unsubscribe any time.

Find open source alternatives to paid software

Openspline vs HeyGen

Feature	Openspline	HeyGen
License	MIT	Proprietary
Self-hosting	Yes (NVIDIA GPU)	No
Real-time streaming	Yes (WebRTC)	Yes
SDK	Python, Node.js	REST API
Pricing	Free (self-hosted)	Per-minute API fees

Openspline vs Tavus

Feature	Openspline	Tavus
License	MIT	Proprietary
Self-hosting	Yes (NVIDIA GPU)	No
Primary use case	Live voice agents	Async and live video
Pricing	Free (self-hosted)	Subscription-based

Openspline vs D-ID

D-ID is a commercial talking-head API serving use cases from marketing video generation to interactive avatars. It has no self-hosted deployment option.

Feature	Openspline	D-ID
License	MIT	Proprietary
Self-hosting	Yes (NVIDIA GPU)	No
Real-time streaming	Yes	Yes (via API)
Pricing	Free (self-hosted)	Per-credit pricing

Who Openspline is for#

AI engineers adding avatar output to an existing voice agent

Skip if:

Teams building face-to-face AI customer support or onboarding agents

Skip if:

Developers building AI tutors, coaches, or interview practice tools

Skip if:

Privacy-conscious deployments needing on-premises avatar inference

Skip if:

The problem it solves#

How it solves it#

Five-line SDK integration

Native connectors for major voice providers

Self-hosted GPU inference

Embeddable player and React component

Interruption handling and continuous idle motion

Custom photo or video backgrounds

Strengths and trade-offs#

Strengths

Trade-offs

Openspline vs alternatives#

Openspline vs HeyGen

Openspline vs Tavus

Openspline vs D-ID

Quick start#

What it's built on#

FAQ#

Similar open-source tools#

Open source tools in these categories#

AI & Machine Learning

Developer Tools

APIs & Integration

Find open source alternatives to paid software

Who Openspline is for#

AI engineers adding avatar output to an existing voice agent

Skip if:

Teams building face-to-face AI customer support or onboarding agents

Skip if:

Developers building AI tutors, coaches, or interview practice tools

Skip if:

Privacy-conscious deployments needing on-premises avatar inference

Skip if:

The problem it solves#

How it solves it#

Five-line SDK integration

Native connectors for major voice providers

Self-hosted GPU inference

Embeddable player and React component

Interruption handling and continuous idle motion

Custom photo or video backgrounds

Strengths and trade-offs#

Strengths

Trade-offs

Openspline vs alternatives#

Openspline vs HeyGen

Openspline vs Tavus

Openspline vs D-ID

Quick start#

What it's built on#

FAQ#

Similar open-source tools#

Open source tools in these categories#

AI & Machine Learning

Developer Tools

APIs & Integration

Find open source alternatives to paid software