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RAW Bitmaps

What is a RAW bitmap? Basically it is a large continuous stream of bytes where each byte represents 8 monochrome pixels. That's it. There is no header at the front to tell the reading application anything about the stream of bytes.

In order to view a RAW bitmap the user has to, at a minimum, inform VLBV of the "width" of the bitmap.

In most cases, the bitmap should be byte aligned - i.e. the width (in pixels) should be a multiple of 8.


LGRaw Bitmap

In cooperation with one of our customers, Artwork defined a bitmap called LGRaw. The specifications are defined below:

extracted from: part_no_6518_1.raw

HEX/ASCII

00000000  4C 47 52 41 57 30 30 38  00 00 00 31 00 00 00 57  LGRAW008...1...W
00000010  01 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  ................
00000020  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  ................
00000030  00 00 00 0F E1 85 EF EB  B8 00 08 26 9F 38 69 30  ...........&.8i0

The Header Section

OFFSETTYPECONTENTSNOTES
0-6ASCIILGRAW00identifies file type
7-10INTEGER38 00 00 00Image width in pixels
11-14INTEGER31 00 00 00Image height in pixels
15-22INTEGER57 01 00 00 00 00 00 00Image file size in Bytes


the bitmap data follows and is encoded as one pixel per bit.

Note:

in this example

38 00 00 00 -> 56

31 00 00 00 -> 49

57 01 00 00 00 00 00 00  -> 1 * 256 + 5 * 16 + 7 = 343