1Jbigtopnm User Manual(0) Jbigtopnm User Manual(0)
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6 jbigtopnm - JBIG to PNM image file converter
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10 jbigtopnm [options] [input-file [output-file]]
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14 This program is part of Netpbm(1).
15 jbigtopnm reads a JBIG bi-level image entity (BIE) from a file or stan‐
17 dard input, decompresses it, and outputs a PBM or PGM file. If the
18 input has one plane, or you choose just one plane of it, the output is
19 PBM. Otherwise, the output is PGM.
20 JBIG is a highly effective lossless compression algorithm for bi-level
22 images (one bit per pixel), which is particularly suitable for scanned
23 document pages.
24 A JBIG encoded image can be stored in several resolutions in one or
26 several BIEs. All resolution layers except the lowest one are stored
27 efficiently as differences to the next lower resolution layer. You can
28 use options -x and -y to stop the decompression at a specified maximal
29 output image size. The input file can consist of several concatenated
30 BIEs which contain different increasing resolution layers of the same
31 image.
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35 -x number
36 Decode only up to the largest resolution layer which is still
37 not more than number pixels wide. If no such resolution layer
38 exists, then use the smallest one available.
39 -y number
42 Decode only up to the largest resolution layer which is still
43 not more than number pixels high. If no such resolution layer
44 exists, then use the smallest one available. You can also use
45 options -x and -y together which selects the largest layer that
46 satisfies both limits.
47 -b Use binary values instead of Gray code words in order to decode
50 pixel values from multiple bitplanes. This option has effect
51 only if the input has more than one bitplane and you don't
52 select just one of those bitplanes. Note that the decoder has
53 to be used in the same mode as the encoder and cannot determine
54 from the BIE, whether Gray or binary code words were used by the
55 encoder.
56 -d Diagnose a BIE. With this option, jbigtopnm only prints a sum‐
59 mary of the header information found in the input file and then
60 exits.
61 -p number
64 If the input contains multiple bitplanes, then extract only the
65 specified single plane as a PBM file. The first plane has num‐
66 ber 0.
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72 This program implements the JBIG image coding algorithm as specified in
73 ISO/IEC 11544:1993 and ITU-T T.82(1993).
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77 jbigtopnm is based on the JBIG library by Markus Kuhn, part of his
78 JBIG-KIT package ⟨http://www.cl.cam.ac.uk/~mgk25/jbigkit/⟩ . The jbg‐
79 topbm program is part of the JBIG-KIT package.
80 jbigtopnm is part of the Netpbm package of graphics tools.
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85 pnm(1), pnmtojbig(1)
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89 If you use jbigtopnm, you are using various patents, particularly on
90 its arithmetic encoding method, and in all probability you do not have
91 a license from the patent owners to do so.
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94 This manual page was generated by the Netpbm tool 'makeman' from HTML
95 source. The master documentation is at
96 http://netpbm.sourceforge.net/doc/jbigtopnm.html
98netpbm documentation 19 November 2003 Jbigtopnm User Manual(0)