According to EXIF 2.31 specs According to EXIF 2.31 specs http://www.cipa.jp/std/documents/e/DC-008-Translation-2016-E.pdf GPSAltitude: Indicates the altitude based on the reference in GPSAltitudeRef. Altitude is expressed as one RATIONAL value. The reference unit is meters. -- Alex Tutubalin @LibRaw LLC reply
According to EXIF 2.31 specs http://www.cipa.jp/std/documents/e/DC-008-Translation-2016-E.pdf
GPSAltitude:
Indicates the altitude based on the reference in GPSAltitudeRef. Altitude is expressed as one
RATIONAL value. The reference unit is meters.