MagTek MICRImage - Manual (Page 26)

MICRImage Check Reader
18
SWI COMMAND – IMAGE PARAMETERS
The SWI Command, shown in Table 2-9, controls the image parameters.
Table 2-9. SWI Command – Image Parameters
BIT FUNCTION
7 6 5 4 3 2 1 0
0 0 200 DPI (Default)
0 1 Reserved
1 0 Reserved
1 1 Reserved
0 Reserved – Set to 0
1 Auto-save image
0 SI command saves image
1 Auto-send image
0 TI command sends image
Image Type
0 0 0 Compressed Bitonal (B/W) CCITT-G4
1 0 0 Bitonal (B/W) (1 Bit/Pixel)
1 0 1 4 Level Grayscale (2 Bits/Pixel)*
1 1 0 16 Level Grayscale (4 Bits/Pixel)
1 1 1 256 Level Grayscale (8 Bits/Pixel)
*This option is not defined in the Base TIFF Specification and may cause problems for some TIFF
viewers.
Image Type
This option selects the number of bits used for each pixel, or in other words, the number of
shades of gray. The bitonal image is compressed using CCITT-G4, a lossless compression (no
loss of image quality), resulting in file sizes approximately 10K. Grayscale images are not
compressed and will be significantly larger (e.g., a personal check using 8-bit Grayscale will
create a file size of approximately 640K).