1Pgmabel User Manual(0) Pgmabel User Manual(0)
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6 pgmabel - create cross section using Abel Integration for Deconvolution
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10 pgmabel [-help] [-axis axis] [-factor factor] [-pixsize pixsize] [-left
11 | -right] [-verbose] [filespec]
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15 This program is part of Netpbm(1).
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17 pgmabel reads as input a PGM image, which it assumes to be an image of
18 a rotational symmetric transparent object. The image must have a ver‐
19 tical symmetry axis. pgmabel produces as output an image of a cross-
20 section of the image.
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22 pgmabel does the calculation by performing the Abel Integration for
23 Deconvolution of an axial-symmetrical image by solving the system of
24 linear equations.
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26 After integration, pgmabel weights all gray-values of one side by the
27 surface area of the calculated ring in square pixels divided by 4*fac‐
28 tor multiplied by the size of one pixel (pixsize). With the -verbose
29 option, pgmabel prints the weighting factors.
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31 Where the calculation generates a negative result, the output is black.
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33 The computation is unstable against periodic structures with size 2 in
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38 In addition to the options common to all programs based on libnetpbm
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40 Common Options ⟨index.html#commonoptions⟩ ), pgmabel recognizes the
41 following command line options:
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43 You can abbreviate any option to its shortest unique prefix.
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48 -help Prints a help message.
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51 -axis axis
52 Position of the axis of symmetry in the image in pixels from the
53 left edge of the image. Default is the center of the image.
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56 -factor factor
57 User defined factor for enhancement of the output. Use a factor
58 less than 1 for decreasing gary values. Default is 1.0.
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61 -pixsize pixsize
62 The size of a pixel for getting scale invariant. Default is
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66 -left Calculate only the left side of the image. You cannot specify
67 both left and right.
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70 -right Analogous to -left.
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73 -verbose
74 print information about the calculation.
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80 Rotate a PGM image to get an image with a vertical axis of symmetry,
81 then calculate the cross section:
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83 pnmrotate 90 file.pgm | pgmabel -axis 140 >cross_section.pgm
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87 pnmrotate(1), pgm(1),
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91 This program was added to Netpbm in Release 10.3 (June 2002).
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95 Volker Schmidt (lefti@voyager.boerde.de)
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97 Copyright (C) 1997-2002 German Aerospace research establishment
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100 This manual page was generated by the Netpbm tool 'makeman' from HTML
101 source. The master documentation is at
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103 http://netpbm.sourceforge.net/doc/pgmabel.html
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105netpbm documentation June 2002 Pgmabel User Manual(0)