ZeliSpeech — Python SDK

A small, dependency-light client for ZeliSpeech — self-hosted, low-latency streaming text-to-speech. Point it at your running server and get audio back in a couple of lines. The SDK talks the same authenticated /v1 API documented in the API reference, so the request/response shapes follow mainstream TTS-API conventions.

Install

pip install zeli-tts

Runtime dep: requests. Live playback (play/stream) shells out to ffplay (ffmpeg), mpv, or afplay.

Quickstart

from zeli_tts import ZeliSpeech, play, save, stream

client = ZeliSpeech(
    base_url="https://voice.zeligate.com",
    api_key="sk-zeli-...",                    # optional if the box runs open
)

# 1) Stream — first audio after the first sentence, not the whole passage
audio = client.text_to_speech.stream(
    voice_id="zeli-voice-1",
    text="Hey there, this is Zeli.",
    output_format="mp3_44100_128",
)
for chunk in audio:
    ...                # audio bytes as they generate

# 2) Stream + play live (needs ffplay or mpv)
stream(client.text_to_speech.stream(voice_id="zeli-voice-1", text="Playing as I generate."))

# 3) One-shot — a finished clip
audio = client.text_to_speech.convert(voice_id="zeli-voice-1", text="Hello world.")
save(audio, "hello.mp3")

Client

ZeliSpeech(base_url, *, api_key=None, timeout=60.0)

• base_url — http://host:8000 or https://voice.zeligate.com; do not include a trailing /v1.
• api_key — sent as Authorization: Bearer … on every request. Required only when the box sets ZELI_API_KEY; a loopback/embedded box can run open.
• client.capabilities() / client.health() / client.is_ready() — engine info and readiness (handy while a box is warming up).

Synthesis — client.text_to_speech

stream(voice_id, text, *, model_id="zeli-turbo", voice_settings=None,
       output_format="mp3_44100_128", timeout=None) -> AudioStream

convert(voice_id, text, *, ...same...) -> bytes

• stream(...) returns an AudioStream — iterate it for audio bytes as they generate; .read() drains it to one blob. It exposes .output_format, .sample_rate, .voice (the resolved voice id), and .request_id.
• convert(...) returns the finished clip in the requested output_format.
• output_format accepts the full menu — mp3_*, wav_*, raw pcm_*, ulaw_8000, alaw_8000, opus_48000_* — see the output formats reference.
• voice_settings (stability/style/speed/…) maps onto Turbo delivery — see voice settings.

Voices — client.voices

client.voices.list()                 # -> [Voice(id, label, description, custom), ...]
client.voices.get("zeli-voice-1")    # -> Voice (404s on unknown ids)
client.voices.add(name="My voice", file="me.wav", description="")  # -> Voice
client.voices.delete("custom-abc123")

add clones a voice zero-shot from a short reference clip (~10–20 s of clean single-speaker audio; file may be a path, a file object, or bytes). Cloning and removal apply to the Turbo engine's custom voices, and require a full API key — ephemeral tokens get 401 insufficient_scope here.

Ephemeral tokens — client.tokens

Never ship a real API key to a browser or mobile app: anyone can read it. The intended flow is that your backend (which holds a full api_key) mints a short-lived, synthesis-only token and hands it to the client, which then talks to the API directly with that token.

tok = client.tokens.create_ephemeral(ttl_seconds=300)
# -> {"token": "zsk_temp_…", "expires_at": 1770000000, "scope": "tts"}

• ttl_seconds is clamped to 30–600 (default 300). expires_at is the epoch second the token dies — enforced server-side on every request, so a leaked token is usable for minutes at most.
• The returned token has scope "tts": it can call synthesis and read endpoints (text_to_speech.stream/convert, voices.list/get) but not voices.add/delete or tokens.create_ephemeral — those return 401 insufficient_scope.
• Minting requires a full key, and 501 not_supported is returned on a server without the portal keys table configured.

Backend endpoint example (FastAPI):

from fastapi import FastAPI
from zeli_tts import ZeliSpeech

app = FastAPI()
zeli = ZeliSpeech(base_url="https://voice.zeligate.com", api_key=os.environ["ZELISPEECH_API_KEY"])

@app.post("/api/tts-token")
def tts_token():
    return zeli.tokens.create_ephemeral(ttl_seconds=300)  # browser uses this directly

More examples

# Delivery control (stability / style / speed map onto Turbo knobs)
clip = client.text_to_speech.convert(
    "zeli-voice-1", "Same words, very different delivery!",
    voice_settings={"stability": 0.2, "style": 0.9, "speed": 1.1},
)

# Raw PCM for your own audio pipeline (24 kHz mono int16, no container)
pcm = client.text_to_speech.convert("zeli-voice-1", "Raw samples.", output_format="pcm_24000")

# Telephony formats
ulaw = client.text_to_speech.convert("zeli-voice-1", "For the phone line.", output_format="ulaw_8000")

# Stream straight to a file as it generates
with open("out.mp3", "wb") as f:
    for chunk in client.text_to_speech.stream("zeli-voice-1", "Written as it speaks."):
        f.write(chunk)

# Clone a voice, use it, remove it
voice = client.voices.add(name="My narrator", file="reference.wav")
client.text_to_speech.convert(voice.id, "Cloned voice speaking.")
client.voices.delete(voice.id)

# Play inline in a Jupyter notebook
from IPython.display import Audio
Audio(data=bytes(client.text_to_speech.convert("zeli-voice-1", "Hello, notebook!")))

# Robust error handling
from zeli_tts import APIError, ConnectionError
try:
    client.text_to_speech.convert("zeli-voice-1", "…")
except APIError as e:
    if e.status == "invalid_api_key":
        ...  # rotate/refresh the key
    elif e.status_code == 503:
        ...  # model still loading — retry shortly
except ConnectionError:
    ...      # box unreachable / stopped

Helpers

from zeli_tts import play, save, stream, pcm_to_wav

play(audio)                    # play a finished clip (any output format)
stream(audio_stream)           # play chunks live; returns the collected bytes
save(audio, "out.mp3")         # write bytes to a file (pcm_* wrapped when .wav)
pcm_to_wav(pcm, sample_rate=24000)

Errors

All derive from ZeliSpeechError:

Auth failures are APIErrors whose .status tells you why:

Migrating from 0.1.x

0.2.0 moves the SDK onto the authenticated /v1 API and adopts the ZeliSpeech naming. ZeliTTS / ZeliTTSError remain as aliases, but the synthesis calls changed: stream(text, voice=...) → stream(voice_id, text), audio now arrives in output_format (mp3 by default) instead of raw PCM, and the engine-knob kwargs (exaggeration, cfg_weight, …) are replaced by voice_settings.