RDIB
From Just Solve the File Format Problem
RDIB (or RIFF DIB) is a raster image file format based on RIFF, and Windows BMP or OS/2 BMP format. There are two varieties: "simple RDIB", which is a standard BMP file in a RIFF container, and "extended RDIB", which is more complex.
Identification
Files begin with bytes 'R' 'I' 'F' 'F' ?? ?? ?? ?? 'R' 'D' 'I' 'B'
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