1Jbigtopnm User Manual(0) Jbigtopnm User Manual(0)
2
3
4
6 jbigtopnm - JBIG to PNM image file converter
7
8
10 jbigtopnm [-xmax] [-ymax] [-binary] [-diagnose] [-plane] [input-file
11 [output-file]]
12
13 Minimum unique abbreviation of option is acceptable. You may use dou‐
14 ble hyphens instead of single hyphen to denote options. You may use
15 white space in place of the equals sign to separate an option name from
16 its value.
17
18
19
21 This program is part of Netpbm(1).
22
23 jbigtopnm reads a JBIG bi-level image entity (BIE) from a file or stan‐
24 dard input, decompresses it, and outputs a PBM or PGM file. If the
25 input has one plane, or you choose just one plane of it, the output is
26 PBM. Otherwise, the output is PGM.
27
28 JBIG is a highly effective lossless compression algorithm for bi-level
29 images (one bit per pixel), which is particularly suitable for scanned
30 document pages.
31
32 A JBIG encoded image can be stored in several resolutions in one or
33 several BIEs. All resolution layers except the lowest one are stored
34 efficiently as differences to the next lower resolution layer. You can
35 use options -x and -y to stop the decompression at a specified maximal
36 output image size. The input file can consist of several concatenated
37 BIEs which contain different increasing resolution layers of the same
38 image.
39
40
42 In addition to the options common to all programs based on libnetpbm
43 (most notably -quiet, see
44 Common Options ⟨index.html#commonoptions⟩ ), jbigtopnm recognizes the
45 following command line options:
46
47 Before Netpbm 10.85 (December 2018), only single-character single-
48 hyphen abbreviations of the options are accepted.
49
50
51
52
53 -xmax number
54 Decode only up to the largest resolution layer which is still
55 not more than number pixels wide. If no such resolution layer
56 exists, then use the smallest one available.
57
58
59 -ymax number
60 Decode only up to the largest resolution layer which is still
61 not more than number pixels high. If no such resolution layer
62 exists, then use the smallest one available. You can also use
63 options -x and -y together which selects the largest layer that
64 satisfies both limits.
65
66
67 -binary
68 Use binary values instead of Gray code words in order to decode
69 pixel values from multiple bitplanes. This option has effect
70 only if the input has more than one bitplane and you don't
71 select just one of those bitplanes. Note that the decoder has
72 to be used in the same mode as the encoder and cannot determine
73 from the BIE, whether Gray or binary code words were used by the
74 encoder.
75
76
77 -diagnose
78 Diagnose a BIE. With this option, jbigtopnm only prints a sum‐
79 mary of the header information found in the input file and then
80 exits.
81
82
83 -plane number
84 If the input contains multiple bitplanes, then extract only the
85 specified single plane as a PBM file. The first plane has num‐
86 ber 0.
87
88
89
90
92 This program implements the JBIG image coding algorithm as specified in
93 ISO/IEC 11544:1993 and ITU-T T.82(1993).
94
95
97 jbigtopnm is based on the JBIG library by Markus Kuhn, part of his
98 JBIG-KIT package ⟨http://www.cl.cam.ac.uk/~mgk25/jbigkit/⟩ . The jbg‐
99 topbm program is part of the JBIG-KIT package.
100
101 jbigtopnm is part of the Netpbm package of graphics tools.
102
103
105 pnm(1), pnmtojbig(1)
106
107
109 There was at one time concern about the need for patent licenses to use
110 jbigtopnm, but any relevant patents expired by 2012.
111
113 This manual page was generated by the Netpbm tool 'makeman' from HTML
114 source. The master documentation is at
115
116 http://netpbm.sourceforge.net/doc/jbigtopnm.html
117
118netpbm documentation 28 July 2020 Jbigtopnm User Manual(0)