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Styles and genres

Online captioners use a range of presentation styles. The following survey discusses appearance and visual behaviour.

Player-native captions

These styles use the built-in captioning features (SMIL, SAMI, QTtext, RealText, or other) of online media players (QuickTime, Real, Windows Media, or other).


Unusual and technically more difficult than offscreen captions, but these are the norm in several other captioned media, including TV and DVD.

Superimposed captions in Slick Caption editor window


Captions that are separated from the video frame are deemed offscreen. They suffer the disadvantage of often being quite wide, sometimes causing marathon line lengths that are hard to read.

Captions whose area is large compared to the video or the entire canvas. Common.
Wide reverse all-caps caption text
Captions whose area is small compared to the video or the entire theatre. Significantly harder to read. Not uncommon.
Flash captions in a single full-width line 1/30 the height of the window
Captions positioned at screen bottom. The norm.
Reverse mixed-case captions at screen bottom
Captions positioned at screen top. Rare.
QuickTime caption sample with (misspelled) caption at window top
Top and bottom
Captions at top and bottom. May include separate caption streams where top- and bottom-positioned captions are always visible and captions where only some captions move to the other position. Rare.
Dual scrolling English/Spanish captions, in huge blocks on top of and below video, respectively
Active use of colour for speaker identification and other differentiation. Rare.
Red colour used for speaker ID (even though speaker is explicitly IDed already)
Captions thoroughly integrated into the entire graphical presentation. Rare.
Captions as one part of a large graphical presentation including video, headlines and titles, and captions-on/off controls


Captions using the player’s native functions that cannot be turned off. Rare.
QuickTime example with offscreen permanent captions rendered by the player itself
Captions permanently rendered as part of the video. Rare.
Burned-in captions in Estonian television commercial

Reused captions

In these styles, captions from another medium (typically television) are reused.

Captions are reused from another medium but are presented with the player’s native functions. Common.
All-caps captions, as if taken from a Line 21 real-time-captioning transcript
Captions permanently rendered as part of the video, usually by decoding TV closed captions. Rare.
Decoded TV closed captions (three lines plus speaker ID on a fourth)


Subtitles unequivocally are not captions, but sometimes subtitles are combined with captions or use presentation methods that could be adapted for captioning. Any kind of translation falls into this category.

Movie trailer with white French subtitles
English subtitles on Flash animation in large canvas
Japanese and English text, with no other video