Blorb Files

Infocom's Z-code format has proved to be a very durable design for writing text adventures. However, by today's standards, the formats they used for graphics and sound are very primitive. In order to address this, Andrew Plotkin came up with the Blorb format.

A Blorb file contains all the graphics and sound files needed for a game. It can also contain the Z-code for the game as well, but does not need to: The game could also be distributed as separate Z-code and Blorb files. If you try to load a Blorb file into Windows Frotz that does not contain Z-code, it will ask you to load the appropriate Z-code file into the interpreter instead.

Blorb files can contain JPEG and PNG graphics files, AIFF sound samples, and MOD and Ogg Vorbis music files. Windows Frotz supports all of these formats, including transparency, opacity and gamma correction for PNG graphics. Windows Frotz also supports Kevin Bracey's extensions to the Blorb format for Infocom's V6 games.

From version 2.0, the Blorb specification also includes iFiction metadata and cover art chunks; Inform 7 can produce Blorb files containing these. If present, Windows Frotz uses them to determine the title of the game and to populate the Help/About This Game dialog.