Model reference · open weights

kotoba-whisper-faster

Available as managed deployment Audio kotoba-tech Speech→text 1 variants 3k dl/mo

kotoba-whisper-faster is an open-weight audio or speech model from kotoba-tech. AxForge deploys and operates it for you on dedicated EU-owned hardware — with the licence handled where one is required.

Available as managed deployment — configured and operated for you on dedicated EU hardware, quoted per deployment.

What it is

Released bykotoba-tech
TypeAudio & music
TaskSpeech→text
Runs withctranslate2
Released2024-09-17
Popularity3k downloads / month
LicenceOpen weights

About

What kotoba-whisper-faster is

This repository contains the conversion of kotoba-tech/kotoba-whisper-v2.0 to the CTranslate2 model format.

This model can be used in CTranslate2 or projects based on CTranslate2 such as faster-whisper.

Read the full model card

Example

Install library and download sample audio.

pip install faster-whisper
wget https://huggingface.co/kotoba-tech/kotoba-whisper-v1.0-ggml/resolve/main/sample_ja_speech.wav

Inference with the kotoba-whisper-v2.0-faster.

from faster_whisper import WhisperModel

model = WhisperModel("kotoba-tech/kotoba-whisper-v2.0-faster")

segments, info = model.transcribe("sample_ja_speech.wav", language="ja", chunk_length=15, condition_on_previous_text=False)
for segment in segments:
    print("[%.2fs -> %.2fs] %s" % (segment.start, segment.end, segment.text))

Benchmark

We measure the inference speed of different kotoba-whisper-v2.0 implementations with four different Japanese speech audio on MacBook Pro with the following spec:

  • Apple M2 Pro
  • 32GB
  • 14-inch, 2023
  • OS Sonoma Version 14.4.1 (23E224)
audio fileaudio duration (min)whisper.cpp (sec)faster-whisper (sec)hf pipeline (sec)
audio 150.35812601807
audio 25.6417361
audio 34.93014154
audio 45.63512669

Scripts to re-run the experiment can be found bellow:

Also, currently whisper.cpp and faster-whisper support the sequential long-form decoding, and only Huggingface pipeline supports the chunked long-form decoding, which we empirically found better than the sequnential long-form decoding.

Conversion details

The original model was converted with the following command:

ct2-transformers-converter --model kotoba-tech/kotoba-whisper-v2.0 --output_dir kotoba-whisper-v2.0-faster \
    --copy_files tokenizer.json preprocessor_config.json --quantization float16

Note that the model weights are saved in FP16. This type can be changed when the model is loaded using the compute_type option in CTranslate2.

More information

For more information about the kotoba-whisper-v2.0, refer to the original model card.

From the published model card. Full card on the HuggingFace links in the sidebar.

How it works

How audio & music work

Audio or textinputAudio modelrecognise / synthesiseText or audiooutputSpeech-to-text turns audio into text; text-to-speech and music models turn text into audio.

Using it via the API

Call it like any OpenAI endpoint

Once AxForge deploys kotoba-whisper-faster for you, it answers on the OpenAI-compatible API — the same base URL and keys as every other model. (kotoba-whisper-faster below is illustrative; you get the exact model name on deployment.)

$ curl -sS https://api.axforge.ai/v1/audio/transcriptions \
  -H "Authorization: Bearer $AXFORGE_API_KEY" \
  -F model="kotoba-whisper-faster" -F file=@audio.mp3

Create an account — your API key is available in the console. 3M free tokens every 30 days with every new account.

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