Presentation Graphics Stream (PGS) is an image-based subtitle format used primarily in Blu-ray Disc media. It contains bitmap graphics for each subtitle, providing high-quality, stylized text. PGS subtitles are typically stored in .sup files and may leverage zlib compression to save space.
History
The Presentation Graphics Stream format was introduced in 2006 as part of the Blu-ray Disc specification developed by the Blu-ray Disc Association. It was designed to accommodate high-definition video content and interactive features of Blu-ray Discs. Initially used exclusively for Blu-ray media, the use of PGS subtitles expanded to other high-definition video platforms. The format's support of multiple languages and subtitle tracks made it a staple in the home video industry.
