# Speech Recognition

## Introduction

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* **Speech Recognition**, often called **Automatic Speech Recognition (ASR)** or **Speech-to-Text (STT)**, is the capability of a machine or program to **identify words spoken** aloud and **convert them into readable text**.
* The sound itself is actually a wave

## Feature Extraction

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* Firstly, convert the original signal into digital format
* Then, divide digital audio into different frames and extract different signal for each frames

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* To identify the pattern and feature of each frame to come up with correct phonemes (The sound unit)

## WER & CER

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* WER and CER are standard to recognize the accuracy of speech recognition
