---
title: Direction definition
framework: quicktime-file-format
role: article
role_heading: Article
path: quicktime-file-format/direction_definition
---

# Direction definition

Define a direction in metadata keys.

## Overview

Overview For the metadata keys which define a direction, com.apple.quicktime.direction.facing and com.apple.quicktime.direction.motion, directions are specified as a string consisting of one or two angles, separated by a slash if two occur. The first is a compass direction, expressed in degrees and decimal degrees, optionally preceded by the characters “+” or “-”, and optionally followed by the character “M”.  The direction is determined as accurately as possible; the nominal due north (zero degrees) is defined as facing along a line of longitude of the location system, unless the angle is followed by the “M” character indicating a magnetic heading. The second is an elevation direction, expressed in degrees and decimal degrees between +90.0 and -90.0, with 0 being horizontal (level), +90.0 being straight up, and -90.0 being straight down (and for these two cases, the compass direction is irrelevant).

## See Also

### Types and usage

- [Extensibility](quicktime-file-format/extensibility.md)
- [Localization list sets](quicktime-file-format/localization_list_sets.md)
- [Type indicator](quicktime-file-format/type_indicator.md)
- [Locale indicator](quicktime-file-format/locale_indicator.md)
- [Data ordering](quicktime-file-format/data_ordering.md)
- [Well-known types](quicktime-file-format/well-known_types.md)
- [Location metadata](quicktime-file-format/location_metadata.md)
- [QuickTime metadata keys](quicktime-file-format/quicktime_metadata_keys.md)
- [Metadata handling](quicktime-file-format/appendix_d_metadata_handling.md)