Also known as: RLE, LGO
The BMP files are the way, Windows stores bit mapped images. The BMP image data is bit packed but every line must end on a dword boundary - if thats not the case, it must be padded with zeroes. BMP files are stored bottom-up, that means that the first scan line is the bottom line. The BMP format has four incarnations, two under Windows (new and old) and two under OS/2, all are described here. OFFSET Count TYPE Description 0000h 2 char ID='BM' - BitMap OS/2 also supports the following IDs : ID='BA' - Bitmap Array ID='CI' - Color Icon ID='CP' - Color Pointer (mouse cursor) ID='IC' - Icon ID='PT' - Pointer (mouse cursor) 0002h 1 dword Filesize of whole file 0006h 4 byte reserved 000Ah 1 dword Offset of bitmap in file ="BOF" 000Eh 1 dword Length of BitMapInfoHeader The BitMapInfoHeader starts directly after this header. 12 - OS/2 1.x format 40 - Windows 3.x format 64 - OS/2 2.x format 0012h 1 dword Horizontal width of bitmap in pixels 0016h 1 dword Vertical width of bitmap in pixels 001Ah 1 word Number of planes 001Ch 1 word Bits per pixel ( thus the number of colors ) ="BPP" 001Eh 1 dword Compression type, see ALGRTHMS.txt for descrip- tion of the different types 0 - none 1 - RLE 8-bit/Pixel 2 - RLE 4-bit/Pixel 0022h 1 dword Size of picture in bytes 0026h 1 dword Horizontal resolution 002Ah 1 dword Vertical resolution 002Ah 1 dword Number of used colors 002Ah 1 dword Number of important colors 0036h ? rec Definition of N colors N=1 shl "BPP" 1 byte Blue component 1 byte Green component 1 byte Red component 1 byte Filler "BOF" ? byte Image data EXTENSION:BMP,RLE,LGO OCCURENCES:PC PROGRAMS:Windows,Paintbrush REFERENCE:DDJ0994 VALIDATION: SEE ALSO:rDIB
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