Python tool to decode base64 encoded data

Authors: Mukesh Choudhary, Mr. Mohit Jain

Certificate: View Certificate

Abstract

Base64 encoding is a process of converting binary data to an ASCII string format by converting that binary data into a 6-bit character representation. The Base64 method of encoding is used when binary data, such as images or video, needs to be transmitted over systems that are designed only to transmit data in a plain text (ASCII) format. Web developers use base64 formats to include images, fonts, sounds and other resources directly inside HTML, JavaScript, JSON and XML files. We estimate that billions of base64 messages are decoded every day. Due to wide use of base64 encoding a decoder software is required. In this project, a tool is developed to decode the base64 encoded data. Tool is developed using Python language, which is the most widely used software language these days. Python is used by hundreds of thousands of programmers and is used in many places. Sometimes only Python code is used for a program, but most of the time it is used to do simple jobs while another programming language is used to do tasks that are more complicated. Its standard library is made up of many functions that come with Python when it is installed. Many libraries available make it possible for the Python language to do more things. These libraries make it a powerful language. it can do many different things. For taking the user input, a GUI is developed in python, which takes the input from user and saves to a text file. The python script uses the text file to extract the data and decode the encoded data. As now days many IOT systems are coming up which need to send small packets of data to the server and later server processes it to make a user understandable data. Like the IOT device sends the data of the home appliances in JSON format and sends it after doing base 64 encoding. This tool will help a user to see the actual data. If the data set is of large size ZIP compression/ decompression can be used. In this way working on this project provided a very useful platform learn Python, GUI, base64 encoding decoding etc.

Introduction

Base64 uses 64 characters that are available (and printable) in most text encoding schemes to represent its data. So how to represent a data byte which can hold 256 different values by a set of only 64 characters? Well, of course this is not possible by a 1:1 mapping, so the Base64 encoded data stream needs more characters than the original byte-based. In fact three data byte values are encoded to four Base64 values: This makes sense as three 8bit values are in total 24bit, while a value in range 0-63 requires 6bit for representation, thus four Base64 characters fit in 24bits. Base64 is an algorithm to convert a stream of bytes into a stream of printable characters (and back). The origin of such binary-to-text encoding scheme like Base64 is the requirement to send a stream of bytes over a communication channel which does not allow binary data but only text-based data. E.g. the ASCII standard is based on seven-bit values, thus uses a range of 0-127. Still an ASCII value is normally stored in a byte which has eight bits (0-255). The usage of the most significant bit of an ascii value is not completely defined (could be used as a parity bit for example). So if a stream which is expected to contain only ASCII values actually also contain nonASCII values, this could potentially lead to problems. This is where Base64 encoding & decoding could come into play.

Conclusion

In this project, we have done review of various existing techniques and tool for base64 encoding decoding. We have gone through various useful technologies, algorithms and methods for encoding and decoding system.