---
title: Subtitle sample data
framework: quicktime-file-format
role: symbol
role_heading: Atom
path: quicktime-file-format/subtitle_sample_data
---

# Subtitle sample data

An atom that contains subtitle sample data.

## Mentioned in

Preparing sound and subtitle alternate groups for use with Apple devices

## Overview

Overview Subtitle sample data consists of a 16-bit word that specifies the length (number of bytes) of the subtitle text, followed by the subtitle text and then by optional sample extensions. The subtitle text is Unicode text, encoded either as UTF-8 text or UTF-16 text beginning with a UTF-16 BYTE ORDER MARK ('\uFEFF') in big or little endian order. There is no null termination for the text. Following the subtitle text, there may be one or more atoms containing additional information for selecting and drawing the subtitle.

## Topics

### Data fields

- [Text size](quicktime-file-format/subtitle_sample_data/text_size.md)
- [Text](quicktime-file-format/subtitle_sample_data/text.md)
- [Sample extensions](quicktime-file-format/subtitle_sample_data/sample_extensions.md)

## See Also

### Storing subtitles

- [Subtitle sample description](quicktime-file-format/subtitle_sample_description.md)
- [Font table atom ('ftab')](quicktime-file-format/font_table_atom.md)
- [Subtitle style atom ('styl')](quicktime-file-format/subtitle_style_atom.md)
- [Text box atom ('tbox')](quicktime-file-format/text_box_atom.md)
- [Subtitle track header size and placement](quicktime-file-format/subtitle_track_header_size_and_placement.md)
- [Referencing a related forced subtitle track](quicktime-file-format/referencing_a_related_forced_subtitle_track.md)