使用 PyAudio、语音识别、pyttsx3 和 SerpApi 构建简单的基于 CLI 的语音助手

德米特里·祖布☀️

一、介绍

        正如您从标题中看到的，这是一个演示项目，显示了一个非常基本的语音助手脚本，可以根据 Google 搜索结果在终端中回答您的问题。

        您可以在 GitHub 存储库中找到完整代码：dimitryzub/serpapi-demo-projects/speech-recognition/cli-based/

        后续博客文章将涉及：

• 使用Flask、一些 HTML、CSS 和 Javascript 的基于 Web 的解决方案。
• 使用Flutter和Dart的基于 Android 和 Windows 的解决方案。

二、我们将在这篇博文中构建什么

2.1 环境准备

        首先，让我们确保我们处于不同的环境中，并正确安装项目所需的库。最难（可能）是 安装 .pyaudio，关于此种困难可以参看下文克服：

   [解决]修复 win 32/64 位操作系统上的 PyAudio pip 安装错误 

2.2 虚拟环境和库安装

        在开始安装库之前，我们需要为此项目创建并激活一个新环境：

# if you're on Linux based systems
$ python -m venv env && source env/bin/activate
$ (env) <path># if you're on Windows and using Bash terminal
$ python -m venv env && source env/Scripts/activate
$ (env) <path># if you're on Windows and using CMD
python -m venv env && .\env\Scripts\activate
$ (env) <path>

        解释python -m venv env告诉 Python 运行 module( -m)venv并创建一个名为 的文件夹env。&&代表“与”。source <venv_name>/bin/activate将激活您的环境，并且您将只能在该环境中安装库。

        现在安装所有需要的库：

pip install rich pyttsx3 SpeechRecognition google-search-results

        现在到pyaudio. 请记住，pyaudio安装时可能会引发错误。您可能需要进行额外的研究。

        如果您使用的是 Linux，我们需要安装一些开发依赖项才能使用pyaudio：

$ sudo apt-get install -y libasound-dev portaudio19-dev
$ pip install pyaudio

如果您使用的是 Windows，则更简单（使用 CMD 和 Git Bash 进行测试）：

pip install pyaudio

三、完整代码

import os
import speech_recognition
import pyttsx3
from serpapi import GoogleSearch
from rich.console import Console
from dotenv import load_dotenvload_dotenv('.env')
console = Console()def main():console.rule('[bold yellow]SerpApi Voice Assistant Demo Project')recognizer = speech_recognition.Recognizer()while True:with console.status(status='Listening you...', spinner='point') as progress_bar:try:with speech_recognition.Microphone() as mic:recognizer.adjust_for_ambient_noise(mic, duration=0.1)audio = recognizer.listen(mic)text = recognizer.recognize_google(audio_data=audio).lower()console.print(f'[bold]Recognized text[/bold]: {text}')progress_bar.update(status='Looking for answers...', spinner='line')params = {'api_key': os.getenv('API_KEY'),'device': 'desktop','engine': 'google','q': text,'google_domain': 'google.com','gl': 'us','hl': 'en'}search = GoogleSearch(params)results = search.get_dict()try:if 'answer_box' in results:try:primary_answer = results['answer_box']['answer']except:primary_answer = results['answer_box']['result']console.print(f'[bold]The answer is[/bold]: {primary_answer}')elif 'knowledge_graph' in results:secondary_answer = results['knowledge_graph']['description']console.print(f'[bold]The answer is[/bold]: {secondary_answer}')else:tertiary_answer = results['answer_box']['list']console.print(f'[bold]The answer is[/bold]: {tertiary_answer}')progress_bar.stop() # if answered is success -> stop progress bar.user_promnt_to_contiune_if_answer_is_success = input('Would you like to to search for something again? (y/n) ')if user_promnt_to_contiune_if_answer_is_success == 'y':recognizer = speech_recognition.Recognizer()continue # run speech recognizion again until `user_promt` == 'n'else:console.rule('[bold yellow]Thank you for cheking SerpApi Voice Assistant Demo Project')breakexcept KeyError:progress_bar.stop()error_user_promt = input("Sorry, didn't found the answer. Would you like to rephrase it? (y/n) ")if error_user_promt == 'y':recognizer = speech_recognition.Recognizer()continue # run speech recognizion again until `user_promt` == 'n'else:console.rule('[bold yellow]Thank you for cheking SerpApi Voice Assistant Demo Project')breakexcept speech_recognition.UnknownValueError:progress_bar.stop()user_promt_to_continue = input('Sorry, not quite understood you. Could say it again? (y/n) ')if user_promt_to_continue == 'y':recognizer = speech_recognition.Recognizer()continue # run speech recognizion again until `user_promt` == 'n'else:progress_bar.stop()console.rule('[bold yellow]Thank you for cheking SerpApi Voice Assistant Demo Project')breakif __name__ == '__main__':main()

四、代码说明

导入库：

import os
import speech_recognition
import pyttsx3
from serpapi import GoogleSearch
from rich.console import Console
from dotenv import load_dotenv

• rich用于在终端中进行漂亮格式化的 Python 库。
• pyttsx3Python 的文本到语音转换器可离线工作。
• SpeechRecognition用于将语音转换为文本的 Python 库。
• google-search-resultsSerpApi 的 Python API 包装器，可解析来自 15 个以上搜索引擎的数据。
• os读取秘密环境变量。在本例中，它是 SerpApi API 密钥。
• dotenv从文件加载环境变量（SerpApi API 密钥）.env。.env文件可以重命名为任何文件：（.napoleon .点）代表环境变量文件。

定义rich Console(). 它将用于美化终端输出（动画等）：

console = Console()

定义main所有发生的函数：

def main():console.rule('[bold yellow]SerpApi Voice Assistant Demo Project')recognizer = speech_recognition.Recognizer()

在函数的开头，我们定义speech_recognition.Recognizer()并将console.rule创建以下输出：

───────────────────────────────────── SerpApi Voice Assistant Demo Project ─────────────────────────────────────

下一步是创建一个 while 循环，该循环将不断监听麦克风输入以识别语音：

while True:with console.status(status='Listening you...', spinner='point') as progress_bar:try:with speech_recognition.Microphone() as mic:recognizer.adjust_for_ambient_noise(mic, duration=0.1)audio = recognizer.listen(mic)text = recognizer.recognize_google(audio_data=audio).lower()console.print(f'[bold]Recognized text[/bold]: {text}')

• console.status-rich进度条，仅用于装饰目的。
• speech_recognition.Microphone()开始从麦克风拾取输入。
• recognizer.adjust_for_ambient_noise旨在根据环境能量水平校准能量阈值。
• recognizer.listen监听实际的用户文本。
• recognizer.recognize_google使用 Google Speech Recongition API 执行语音识别。lower()是降低识别文本。
• console.print允许使用文本修改的语句rich print，例如添加粗体、斜体等。

spinner='point'将产生以下输出（使用python -m rich.spinner查看列表spinners）：

之后，我们需要初始化 SerpApi 搜索参数以进行搜索：

progress_bar.update(status='Looking for answers...', spinner='line') 
params = {'api_key': os.getenv('API_KEY'),  # serpapi api key   'device': 'desktop',              # device used for 'engine': 'google',               # serpapi parsing engine: https://serpapi.com/status'q': text,                        # search query 'google_domain': 'google.com',    # google domain:          https://serpapi.com/google-domains'gl': 'us',                       # country of the search:  https://serpapi.com/google-countries'hl': 'en'                        # language of the search: https://serpapi.com/google-languages# other parameters such as locations: https://serpapi.com/locations-api
}
search = GoogleSearch(params)         # where data extraction happens on the SerpApi backend
results = search.get_dict()           # JSON -> Python dict

progress_bar.update将会progress_bar用新的status（控制台中打印的文本）进行更新，spinner='line'并将产生以下动画：

之后，使用 SerpApi 的Google 搜索引擎 API从 Google 搜索中提取数据。

代码的以下部分将执行以下操作：

try:if 'answer_box' in results:try:primary_answer = results['answer_box']['answer']except:primary_answer = results['answer_box']['result']console.print(f'[bold]The answer is[/bold]: {primary_answer}')elif 'knowledge_graph' in results:secondary_answer = results['knowledge_graph']['description']console.print(f'[bold]The answer is[/bold]: {secondary_answer}')else:tertiary_answer = results['answer_box']['list']console.print(f'[bold]The answer is[/bold]: {tertiary_answer}')progress_bar.stop()  # if answered is success -> stop progress baruser_promnt_to_contiune_if_answer_is_success = input('Would you like to to search for something again? (y/n) ')if user_promnt_to_contiune_if_answer_is_success == 'y':recognizer = speech_recognition.Recognizer()continue         # run speech recognizion again until `user_promt` == 'n'else:console.rule('[bold yellow]Thank you for cheking SerpApi Voice Assistant Demo Project')breakexcept KeyError:progress_bar.stop()  # if didn't found the answer -> stop progress barerror_user_promt = input("Sorry, didn't found the answer. Would you like to rephrase it? (y/n) ")if error_user_promt == 'y':recognizer = speech_recognition.Recognizer()continue         # run speech recognizion again until `user_promt` == 'n'else:console.rule('[bold yellow]Thank you for cheking SerpApi Voice Assistant Demo Project')break

最后一步是处理麦克风没有拾取声音时的错误：

# while True:
#     with console.status(status='Listening you...', spinner='point') as progress_bar:
#         try:# speech recognition code# data extraction codeexcept speech_recognition.UnknownValueError:progress_bar.stop()         # if didn't heard the speech -> stop progress baruser_promt_to_continue = input('Sorry, not quite understood you. Could say it again? (y/n) ')if user_promt_to_continue == 'y':recognizer = speech_recognition.Recognizer()continue               # run speech recognizion again until `user_promt` == 'n'else:progress_bar.stop()    # if want to quit -> stop progress barconsole.rule('[bold yellow]Thank you for cheking SerpApi Voice Assistant Demo Project')break

console.rule()将提供以下输出：

───────────────────── Thank you for cheking SerpApi Voice Assistant Demo Project ──────────────────────

添加if __name__ == '__main__'惯用语，以防止用户在无意时意外调用某些脚本，并调用main将运行整个脚本的函数：

if __name__ == '__main__':main()

五、链接

• rich
• pyttsx3
• SpeechRecognition
• google-search-results
• os
• dotenv