Quantization for OpenAI's Whisper Models: A Comparative Analysis
Authors: name: Allison Andreyev
Published: 2025-03-12 23:50:35

Abstract: Automated speech recognition (ASR) models have gained prominence for
applications such as captioning, speech translation, and live transcription.
This paper studies Whisper and two model variants: one optimized for live
speech streaming and another for offline transcription. Notably, these models
have been found to generate hallucinated content, reducing transcription
reliability. Furthermore, larger model variants exhibit increased latency and
pose challenges for deployment on resource-constrained devices. This study
analyzes the similarities and differences between three Whisper models,
qualitatively examining their distinct capabilities. Next, this study
quantifies the impact of model quantization on latency and evaluates its
viability for edge deployment. Using the open source LibriSpeech dataset, this
paper evaluates the word error rate (WER) along with latency analysis of
whispercpp using 3 quantization methods (INT4, INT5, INT8). Results show that
quantization reduces latency by 19\% and model size by 45\%, while preserving
transcription accuracy. These findings provide insights into the optimal use
cases of different Whisper models and edge device deployment possibilities. All
code, datasets, and implementation details are available in a public GitHub
repository: https://github.com/allisonandreyev/WhisperQuantization.git