add cartesia synthesizer

[rjheeta]

Add support for Cartesia (https://docs.cartesia.ai/)

[macwilk]

we should use the SynthesizerConfig default of audio_encoding for defining audio encodings and set it to the string expected by the cartesia API similar to here

[macwilk]

Suggested change

	cartesia_tts = None
	def __init__(
	self,
	synthesizer_config: CartesiaSynthesizerConfig,
	):
	super().__init__(synthesizer_config)
	# Lazy import the cartesia module
	if CartesiaSynthesizer.cartesia_tts is None:
	from cartesia.tts import AsyncCartesiaTTS
	CartesiaSynthesizer.cartesia_tts = AsyncCartesiaTTS
	def __init__(
	self,
	synthesizer_config: CartesiaSynthesizerConfig,
	):
	super().__init__(synthesizer_config)
	# Lazy import the cartesia module
	try:
	from cartesia.tts import AsyncCartesiaTTS
	except ImportError as e:
	raise ImportError(
	f"Missing required dependancies for CartesiaSynthesizer"
	) from e
	self.cartesia_tts = AsyncCartesiaTTS

[macwilk]

Suggested change

	self.client = AsyncCartesiaTTS(api_key=self.api_key)
	self.client = self.cartesia_tts(api_key=self.api_key)

[macwilk]

could you convert this to a create_speech_uncached implementation?

check out our Eleven Labs implementation here as a good example of how to achieve this as it shouldn't require much changes to the existing code to get it up and running!

[rjheeta]

@macwilk I just realized this is going to generate unintended consequences (specifically, slowed-down sounding audio) if we had initialized the Synthesizer with from_telephone_output_device() because it will be trying to pass DEFAULT_SAMPLING_RATE (8000).

[ajar98]

pretty simple fixes that you can auto apply from the UI, then you should be g2g!

ajay approved

[rjheeta]

@ajar98 the test/build failed with this notice.

Run python -m poetry install -E all
Creating virtualenv vocode-zqFtuvVc-py3.10 in /home/runner/.cache/pypoetry/virtualenvs
Installing dependencies from lock file
Warning: poetry.lock is not consistent with pyproject.toml. You may be getting improper dependencies. Run `poetry lock [--no-update]` to fix it.

So I just ran poetry lock --no-update and checked it in