SubStation Alpha

SubStation Alpha (SSA), also known as Advanced Substation Alpha (ASS) for v4+, is a subtitle format. It was originally used by the Windows program of the same name, aimed at the karaoke and anime communities. It’s advanced styling compared to alternatives made it popular with release groups.

Overview

SSA is a “plain” text format, with Unicode support in ASS. It can either be left as a plain text file with the extension of .ssa or .ass, or muxed into a Matroska (.mkv) or AVI (.avi) file. The original SubStation Alpha software is abandonware, however a wide variety of media authoring, muxing, and playing software supports SSA, including VLC, MPV, and FFmpeg.

Format

SSA uses the word “script” to refer to the subtitles that track a video. The character ’;’ at the beginning of a line is used to mark comments.

ASS (SSA v4+) header

[Script Info]
; This is an Advanced Sub Station Alpha v4+ script.
; For Sub Station Alpha info and downloads,
; go to http://www.eswat.demon.co.uk/
; or email [email protected]
;
; Advanced Sub Station Alpha script format developed by #Anime-Fansubs@EfNET
; http://www.anime-fansubs.org
;
; For additional info and downloads go to http://vobsub.edensrising.com/
; or email [email protected]
;
; Note: This file was saved by Subresync.
;
ScriptType: v4.00+
Collisions: Normal
PlayResX: 384
PlayResY: 288
Timer: 100.0000

[V4+ Styles]
Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding
Style: Default,Tahoma,16,&H00000000,&H00ffffff,&H00ffffff,&H00c0c0c0,-1,0,0,0,100,100,0,0.00,1,2,3,2,20,20,20,1

[Events]
Format: Layer, Start, End, Style, Actor, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:01:41.70,0:01:46.84,Default,,0000,0000,0000,,Le rugissement des larmes !\NTu es mon ami.
Dialogue: 0,0:02:00.99,0:02:02.87,Default,,0000,0000,0000,,Est-ce vraiment Naruto ?

Further reading:

Multimedia wiki

Specification

Archived original software release