Via this post,

File: opendm/video/video2dataset.py
Altitude values are correctly parsed from the SRT file, but they are rounded to an integer when written to EXIF:
gps_ifd[piexif.GPSIFD.GPSAltitude] = float_to_rational(round(altitude))
# 192.048 -> 192

This causes loss of vertical accuracy, which is critical for RTK and precise ground surveys.
Suggested fix:
gps_ifd[piexif.GPSIFD.GPSAltitude] = float_to_rational(altitude)
or (to preserve millimeter precision with a stable denominator):
gps_ifd[piexif.GPSIFD.GPSAltitude] = float_to_rational(round(altitude * 1000) / 1000)