📦 Ravdec - Lossless Data Compression

🔹 Overview

Ravdec is a Python module implementing a lossless data compression algorithm designed by Ravin Kumar on September 19, 2016. This algorithm is designed exclusively for textual data, including alphabets, numbers, and symbols. The algorithm offers two modes:

• When enforced_8char_input=True, the length of input data must be exactly divisible by 8, ensuring a fixed compression ratio of 1.1429.
• When enforced_8char_input=False, the compression ratio starts at 1.0435 for a 24-character input (minimum required length) and increases with input size, approaching 1.1429 for larger inputs.

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🔧 Development Details

• 👨‍💻 Developer: Ravin Kumar
• 📂 GitHub Repository: https://github.com/mr-ravin/ravdec/
• 🌐 JavaScript Implementation: https://github.com/mr-ravin/ravdecjs/

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📊 Compression Ratio

✅ When enforced_8char_input=False

• Compression ratio starts at 1.0435 for a 24-character input (minimum required length).
• Gradually increases, reaching 1.14 at 912-character length, and further approaches 1.1429 as input size increases.
• Ideal for handling variable-length text data while still achieving efficient compression.

🚀 When enforced_8char_input=True

• Original data length must be exactly divisible by 8, ensuring a fixed compression ratio of 1.1429.
• Much faster, making it suitable for high-speed data compression.
• Best for real-time systems where data is continuously growing and frequency-based algorithms are time-consuming.

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⏳ Complexity Analysis

1️⃣ enforced_8char_input = True

• ✅ Time Complexity: O(n)

• ✅ Fixed Compression Ratio (1.1429)

• ✅ Ideal for continuously growing data

• ✅ Direct 7-bit conversion per character

• ✅ No padding calculations

• ✅ Optimized for speed

2️⃣ enforced_8char_input = False

• 📌 Time Complexity: O(n) (with minor overhead)

• 📌 Compression ratio varies (~1.04 - 1.1429)

• 📌 Needs Padding Overhead

• ✅ Direct 7-bit conversion per character

• 📌 Padding calculation and storage overhead

• 📌 Slower compared to enforced mode

📌 Comparison Table

Mode	Time Complexity	Compression Ratio	Padding Overhead	Best Use Case
enforced_8char_input = True	O(n)	Fixed (1.1429)	❌ No Padding	High-speed data streams
enforced_8char_input = False	O(n) (with minor overhead)	Variable (~1.04 - 1.1429)	✅ Needs Padding	General text compression

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🎯 Use Cases

• 📜 Log File Compression: Reduces storage space while maintaining quick retrieval.
• ⚡ High-Speed Data Transmission: Faster processing with enforced_8char_input=True.
• 📈 Fixed Compression Ratio Scenarios: Ideal for predictable compression requirements.
• 📁 Data Archiving: Efficient text storage without losing information.
• ⏳ Real-Time Compression: enforced_8char_input=True ensures immediate compression without extra calculations.

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🚀 Features

• ✅ Fixed compression ratio up to 1.1429 for enforced_8char_input=True.
• ✅ Supports alphabets, numbers, and symbols.
• ✅ Optimized for real-time and high-speed data transmission.

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🛠️ Functions

📌 file_compression(filename, enforced_8char_input=False)

Compresses a text file and saves the compressed data with the .rdc extension.

📌 file_decompression(filename, enforced_8char_input=False)

Decompresses a previously compressed .rdc file back to its original form.

📌 compression(read_data, enforced_8char_input=False)

Compresses a string using 7-bit storage, returning a compressed string.

📌 decompression(compressed_text, enforced_8char_input=False)

Decompresses a compressed string back to its original form.

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📥 Installation

Install using pip:

pip install ravdec

or,

pip install git+https://github.com/mr-ravin/ravdec.git

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📌 Dependencies:

• Python >= 3.7
• No additional dependencies required

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🔄 Example Usage

✍ Compressing and Decompressing Text

import ravdec

# When enforced_8char_input=True

data = 'Ravdec !'  # Length of data is divisible by 8

# Compress a string with enforced_8char_input=True
compressed_data = ravdec.compression(data, enforced_8char_input=True) # compressed_data is '¥\x87¶L¸Ð!'

# Decompress the string
decompressed_data = ravdec.decompression(compressed_data, enforced_8char_input=True)
print(compressed_data)    # Output: '¥\x87¶L¸Ð!'
print(decompressed_data)  # Output: 'Ravdec !'



# When enforced_8char_input=False (and input data has length >= 24)

data = 'R'*25
# Compress a string with enforced_8char_input=False
compressed_data = ravdec.compression(data) # by default enforced_8char_input=False

# Decompress the string
decompressed_data = ravdec.decompression(compressed_data) # by default enforced_8char_input=False
print(compressed_data)
print(decompressed_data)

🗂️ Compressing and Decompressing Files

import ravdec

original_filename = "inputfile.txt"
compressed_filename = filename+".rdc"

# Compress a file
ravdec.file_compression(original_filename) # saves compressed data in compressed_filename

# Decompress the previously compressed file
ravdec.file_decompression(compressed_filename) # saves the decompressed data in original_filename (got after removing '.rdc' from compressed_filename)

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📜 Copyright License

Copyright (c) 2016 Ravin Kumar
Website: https://mr-ravin.github.io

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation 
files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, 
modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the 
Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the 
Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE 
WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR 
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.