Canon FAX-L1000 - Manual (Page 235)

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FAX-L1000 Chapter 3: Technical Reference
3.2 JBIG Image Compression Encoding Method
3.2.1 Outline of the JBIG Image Compression Encoding Method
The JBIG Image Compression Encoding Method is recommended in ITU-T T.82/T.85 as a
new bi-level (bi-level: White and Black) image compression encoding method developed by
JBIG (Joint Bi-level Image experts Group).
The JBIG Image Compression Encoding Method has the following characteristics with
regards to text documents, quasi-gray scale images with little continuous black and white, and
gray scale images which use a dithering method: a higher compression rate (1.1~30 times
higher) than the conventional MMR compression method, the encoded volume will not
exceed the volume of original image information after compression, and when decoding, the
image can be completely re-assembled to its original condition in the same way as with
conventional MR/MMR.
The JBIG Image Compression Encoding Method contains Progressive Bi-level Image
Compression for searching image databases, recommended in ITU-T T.82, and Single
Progression Sequential Bi-level Image Compression for facsimile, recommended in ITU-T
T.82 and T.85.
Images will take on the form shown below.
Figure 3-41 Images
Progressive
Sequential