Astro Sonification: Approach to Astronomical Data Representation

Abstract

This project presents a methodology for the sonification of galactic imagery, transforming visual data into an auditory format. By analyzing the red, green, and blue (RGB) pixel values of galaxy images, we establish a mapping between color and brightness characteristics and corresponding musical parameters, including melody, rhythm, and timbre. This approach offers a novel perspective on astronomical data exploration, facilitating a multi-sensory understanding of celestial structures.

Project Scope

This repository provides a framework for the following functionalities:

• Data Acquisition: Loading of galactic image data from a designated .npy file.
• Pixel-Level Analysis: Extraction and analysis of RGB color information from the acquired images.
• Visual Representation: Generation of image visualizations using OpenCV and matplotlib, complemented by heatmap generation for pattern identification.
• Data Serialization: Export of extracted pixel data to a CSV file for subsequent computational analysis and processing.
• Auditory Transformation: Implementation of a sonification algorithm that maps visual data to auditory parameters, specifically:
  • Correlation of pixel brightness with auditory pitch.
  • Modulation of auditory volume based on the red channel values.
  • Determination of note duration based on the blue channel values.

Sonification Mapping Protocol

1. RGB-Frequency Mapping:

   The red, green, and blue components of each pixel are mapped to distinct frequency ranges, generating corresponding tonal characteristics:

   • Red: Lower frequency spectrum.
   • Green: Mid-frequency spectrum.
   • Blue: Higher frequency spectrum.

   This process synthesizes a harmonic composition of sine waves, creating an auditory representation of the image's spectral content.

2. Luminosity-Pitch Correlation:

   Pixel luminosity is directly correlated with auditory pitch:

   • Increased luminosity corresponds to higher frequency values.
   • Decreased luminosity corresponds to lower frequency values.

   This mapping facilitates an auditory representation of the image's light and shadow distribution.

3. Red Channel-Volume Modulation:

   The intensity of the red channel is utilized to modulate auditory volume:

   • Higher red channel values result in increased auditory amplitude.
   • Lower red channel values result in decreased auditory amplitude.

4. Blue Channel-Duration Mapping:

   The blue channel is employed to govern the temporal duration of auditory events:

   • Lower blue channel values result in extended note durations.
   • Higher blue channel values result in shortened, percussive note durations.

Project Architecture

• data/: Directory containing the galactic image dataset.
• .ipynb Notebooks: Interactive computational notebooks containing the implemented code for image processing and sonification.
• output/: Directory for the storage of extracted color data and generated visual outputs.