BSAVE Image

Revision as of 04:21, 28 December 2023

BSAVE Image (or BSAVED Image, BSAVE graphics, BSV, BLOAD format, etc.) is a loosely-defined family of raster and character-based graphics file formats, based on the behavior of the BSAVE and BLOAD commands in QuickBASIC and certain other implementations of the BASIC programming language. This article is mainly about the formats used by DOS/PC software.

The file consists of a header, followed by a raw dump of video memory (or something approximating that). The Wikipedia article seems to be the best source of information about it.

BSAVE Image files are not very portable. There are many varieties of them, and no reliable way to distinguish all of them.

Format details

BSAVE Image files (of the PC variety) begin with the byte 0xFD. They may have a 7-byte header, or an 11-byte header that includes the width (measured in bits, not pixels) and height.

After the image data, there might or might not be a 0x1A (Ctrl+Z) byte, and/or extra data or padding.

Platform-specific images

Since BSAVE images are raw dumps of graphic data in memory, they are platform-specific and depend in format on how the graphics are stored (and on what header bytes are attached to binary files) on the particular platform on which they were created. Some of the platform-specific graphics are documented here:

• Apple II graphics formats
• Atari graphics formats
• Commodore graphics formats
• MSX BASIC graphics and Graph Saurus

Identification

A BSAVE file starts with the byte 0xfd.

One issue to be aware of is that both BSAVE and compressed MegaPaint BLD can start with 0xfd, and can use the .bld extension.

(TODO: Discuss heuristics that can help to identify BSAVE files.)

See also

• PCPaint BSAVE

Software

• Deark

(This section needs expansion. There are many DOS programs that support BSAVE in some way.)

Sample files

• Between Heaven and Hell Version II CD → 100/{8, 21, 22, 92}, 200/{109, 111, 112}, 300/{218, 230, 265}, 400/{349, 393}, 500/{419, 431, 432} (some images are adult-oriented)
• http://cd.textfiles.com/advheaven2/PUZZLES/DRCODE12/
• http://cd.textfiles.com/advheaven2/SOLITAIR/SP107/
• http://cd.textfiles.com/vgaspectrum/games/unzip/hurkle/
• http://cd.textfiles.com/advswgames/LASTHALF/ → *.PIX
• http://cd.textfiles.com/hamradio/misc/mapr86/
• http://cd.textfiles.com/hamradio/misc/monalith/
• kd_lib1.zip
• dexvert samples — image/bsave

Links

• Wikipedia: BSAVE (bitmap format)
• Micosoft Support: BSAVE/BLOAD File Format Explained for Basic
• QuickBasic BSAVE Format
• Pictor PC Paint File Format Summary from the Encyclopedia of Graphics File Formats - Has information about the BSAVE format used by PC Paint