In this tutorial, we are going to build a telegram chatbot capable of performing optical character recognition (OCR).

Introduction

In this tutorial, we are going to build a telegram chatbot capable of performing optical character recognition (OCR). Telegram is a cloud-based mobile and desktop messaging app with a focus on security and speed. Optical Character Recognition (OCR) is the process of electronically extracting text from images, videos, or any type of documents.

To build this telegram bot we are going to use Node.js with the following modules telegraf, node-tesseract-ocr, node-ffmpeg, dotenv, and axios.

• telegraf is a Telegram bot framework that makes the development of bots easy and straightforward
• node-tesseract-ocr is a Node.js wrapper for the Tesseract OCR API. Tesseract is an OCR engine that is able to extract text from various media formats. We will use this module to extract text from images
• node-ffmpeg is a FFmpeg module for Node. This library provides a set of functions and utilities to abstract command-line usage of ffmpeg. FFmpeg is a collection of libraries and tools to process multimedia content such as audio, video, subtitles, and related metadata. We will use this module to extract a frame from a video, so that we can then use Tesseract to extract text from said frame
• dotenv is a node.js module that loads environment variables from a .env file into process.env. We will use this module to store our bot credentials
• axios is a module that provides us a promise-based HTTP client for the browser and node.js. We will use this module to download images to a folder located in our server.

At the end of this tutorial, you will have a bot that can extract text from images and videos sent to it.

Prerequisites

In order to follow this tutorial, you will need to:

• Have a basic understanding of how to use Node
• Have node.js, npm, tesseract, and ffmpeg installed on your computer

#chatbot #telegram