Convert FIT to FITS

Understanding the FIT and FITS file formats

FIT files are primarily used for storing activity data from fitness devices, such as Garmin GPS trackers. The FIT (Flexible and Interoperable Data Transfer) format is a proprietary binary format designed for efficient storage and transfer of fitness-related data, including heart rate, GPS coordinates, and workout statistics.

FITS files, on the other hand, stand for Flexible Image Transport System. This format is widely used in astronomy for storing, transmitting, and processing scientific images and data. FITS files can contain multidimensional arrays (such as images) and tables, along with metadata describing the data content.

Why convert FIT to FITS?

Converting a FIT file to a FITS file is not a common operation, as these formats serve very different purposes. However, in some scientific or research contexts, you may want to analyze fitness data using astronomical tools or store it in a standardized scientific format. This conversion allows for broader compatibility with data analysis software used in research environments.

How to convert FIT to FITS

Since FIT and FITS are fundamentally different, direct conversion is not natively supported by most software. The process typically involves:

• Extracting data from the FIT file (such as GPS tracks or sensor readings).
• Structuring this data into a format compatible with FITS (e.g., as a table or image array).
• Saving the structured data as a FITS file using appropriate software.

Recommended software for FIT to FITS conversion

Python is the best tool for this conversion, using libraries such as fitparse (for reading FIT files) and astropy.io.fits (for writing FITS files). Here’s a basic workflow:

1. Install the required libraries: pip install fitparse astropy
2. Use fitparse to extract data from the FIT file.
3. Organize the data into a table or array.
4. Use astropy.io.fits to write the data to a FITS file.

For users preferring graphical interfaces, there are no direct GUI converters, but you can use TOPCAT (for FITS table manipulation) after exporting the FIT data to CSV and then importing it into FITS format.

Step-by-step conversion example using Python

1. Extract data from FIT file:

   from fitparse import FitFile
   fitfile = FitFile('activity.fit')
   data = [record.get_values() for record in fitfile.get_messages('record')]

2. Convert to FITS table:

   from astropy.table import Table
   from astropy.io import fits
   table = Table(rows=data)
   table.write('activity.fits', format='fits')

This process ensures your fitness data is preserved in a scientific format suitable for advanced analysis.