using with whisper.cpp

Please refer to these PRs, both whisper.cpp and whisper-rs require small changes:

https://github.com/tazz4843/whisper-rs/pull/75 https://github.com/ggerganov/whisper.cpp/pull/1130

Mel Spec

A Rust implementation of mel spectrograms aligned to the results from the whisper.cpp, pytorch and librosa reference implementations and suited to streaming audio.

The main objective is to allow inference from spectrograms alone, so that audio samples don't need to be kept in context for follow-up processing.

filter banks

Mel filter banks are within 1.0e-7 of librosa.filters.mel and identical to the GGML model-embedded filters used by whisper.cpp.

stft

A stft implementation that allows creating spectrograms from an audio steam - near identical to those produced by whisper.cpp internally.

An example of whisper inference from mel spectrograms via whisper-rs can be found in the tests.