DTMF Encoder/Decoder

This project is a Dual-Tone Multi-Frequency (DTMF) encoder and decoder, developed as part of the High Performance Coding class. The system is designed to encode a text message into DTMF tones and decode the tones back into text.

Features

• Encode text messages into DTMF tones stored in a .wav file
• Decode DTMF tones using two different methods:
  • Frequency-based decoding (using Fourier Transform)
  • Time-domain decoding (using correlation analysis)
• High-performance implementation with execution time analysis

Quick Start Guide

1. Compile the project

mkdir -p build
cd build
cmake ..
make -j$(nproc)
cd ..

2. Encode a message

Save your message in a text file:

echo "hello, world!" > message.txt

Then encode it into a .wav file:

./build/dtmf_encdec encode message.txt message.wav

Example output:

Encoding alone took 0.014179 seconds

3. Decode the message

Frequency-based decoder:

./build/dtmf_encdec decode message.wav

Example output:

Using 0.539966 as silence amplitude threshold
Decoding alone took 0.017162 seconds
Decoded: hello, world!

Time-domain decoder:

./build/dtmf_encdec decode_time_domain message.wav

Example output:

Using 0.539966 as silence amplitude threshold
Decoding alone took 0.001462 seconds
Decoded: hello, world!

Constraints and Limitations

This implementation assumes:

1. A fixed duration of 0.2s per character.
2. A 0.2s pause between characters.
3. A 0.05s pause between multiple keypresses for the same character.

Report

The report for this project's, in french, can be found here

Disclaimer

This project was developed for educational purposes as part of a High Performance Coding course. While optimized for speed, it is not intended for production use in critical systems.

License

This project is released as open-source under the MIT License. Feel free to contribute or modify as needed!