1Pamcut User Manual(0)                                    Pamcut User Manual(0)
2
3
4

NAME

6       pamcut - cut a rectangle out of a PAM, PBM, PGM, or PPM image
7
8

SYNOPSIS

10       pamcut
11
12       [-left colnum]
13
14       [-right colnum]
15
16       [-top rownum]
17
18       [-bottom rownum]
19
20       [-width cols]
21
22       [-height rows]
23
24       [-pad]
25
26       [-cropleft numcols]
27
28       [-cropright numcols]
29
30       [-croptop numrows]
31
32       [-cropbottom numrows]
33
34       [-verbose]
35
36       [left top width height]
37
38       [pnmfile]
39
40       Minimum  unique  abbreviations  of  option are acceptable.  You may use
41       double hyphens instead of single hyphen to denote options.  You may use
42       white space in place of the equals sign to separate an option name from
43       its value.
44
45

DESCRIPTION

47       This program is part of Netpbm(1).
48
49       pamcut reads a PAM, PBM, PGM, or PPM image as input  and  extracts  the
50       specified rectangle, and produces the same kind of image as output.
51
52       You can specify either the rectangle to cut out and keep or specify the
53       edges to crop off and discard, or a combination.
54
55       To request edges be cropped off,  use  options  -cropleft,  -cropright,
56       -croptop,  and -cropbottom to indicate how many rows or columns to dis‐
57       card.
58
59       For example, -cropleft=50 -cropright=200 means to discard the  leftmost
60       50 and rightmost 200 columns.
61
62       To  specify  the  rectangle  to keep, use -left, -right, -top, -bottom,
63       -width, -height, and -pad options.
64
65       For example, -left=50 -right=200 means to keep the 150 columns  between
66       Columns 50 and 200 inclusive.
67
68       You  can  code  any  mixture  of  the  options.  What you don't specify
69       defaults.  Those defaults are in favor of minimal cutting and in  favor
70       of cutting the right and bottom edges off.  It is an error to overspec‐
71       ify, i.e. to specify all three of -left, -right, and  -width  or  -top,
72       -bottom, and -height or right as well as -cropright.
73
74       There  is  an  older  way  to specify the rectangle to keep: positional
75       arguments.  Arguments were the only way available before July 2000, but
76       you  should  not  use  them in new applications.  Options are easier to
77       remember and read, more expressive, and allow you to use defaults.
78
79       If you use both options and arguments, the two specifications get mixed
80       in an unspecified way.
81
82       To  use arguments, specify all four of the left, top, width, and height
83       arguments.  left and top have the same effect as specifying them as the
84       argument  of  a  -left  or -top option, respectively.  width and height
85       have the same effect as specifying them as the argument of a -width  or
86       -height  option, respectively, where they are positive.  Where they are
87       not positive, they have the same effect as specifying one less than the
88       value  as  the  argument  to  a -right or -bottom option, respectively.
89       (E.g. width = 0 makes the cut go  all  the  way  to  the  right  edge).
90       Before  July  2000,  negative  numbers  were  not allowed for width and
91       height.
92
93       Input is from Standard Input if you don't specify the input  file  pnm‐
94       file.
95
96       Output is to Standard Output.
97
98       pamcut works on a multi-image stream.  It cuts each image in the stream
99       independently and produces a multi-image stream output.  Before  Netpbm
100       10.32 (March 2006), it ignored all but the first image in the stream.
101
102       If  you  are  splitting  a single image into multiple same-size images,
103       pamdice is faster and easier than running pamcut multiple times.
104
105       pamcomp is also useful for cutting and padding an image  to  a  certain
106       size.   You  create  a background image of the desired frame dimensions
107       and overlay the subject image on it.
108
109

OPTIONS

111       In addition to the options common to all programs  based  on  libnetpbm
112       (most notably -quiet, see
113        Common  Options  ⟨index.html#commonoptions⟩  ),  pamcut recognizes the
114       following command line options:
115
116
117
118       -left=colnum
119              The column number of the leftmost column to be  in  the  output.
120              Columns  left  of this get cut out.  If a nonnegative number, it
121              refers to columns numbered from 0 at the left, increasing to the
122              right.   If  negative,  it  refers to columns numbered -1 at the
123              right, decreasing to the left.
124
125
126       -right=colnum
127              The column number of the rightmost column to be in  the  output,
128              numbered  the  same  as for -left.  Columns to the right of this
129              get cut out.
130
131
132       -top=rownum
133              The row number of the topmost row to be  in  the  output.   Rows
134              above  this  get  cut out.  If a nonnegative number it refers to
135              rows numbered from 0 at the top, increasing downward.  If  nega‐
136              tive, it refers to columns numbered -1 at the bottom, decreasing
137              upward.
138
139
140       -bottom=rownum
141              The row number of the bottom-most row to be in the output,  num‐
142              bered the same as for -top.  Rows below this get cut out.
143
144
145       -width=cols
146              The number of columns to be in the output.  Must be positive.
147
148
149       -height=rows
150              The number of rows to be in the output.  Must be positive.
151
152
153       -cropleft
154
155       -cropright
156
157       -croptop
158
159       -cropbottom
160              These  options  tell  how  many rows or columns to crop from the
161              left, right, top, or bottom edges, respectively.
162
163              The value must not be negative.
164
165              These option were new in Netpbm 10.85 (December  2018).   Before
166              that,  you can achieve the same thing with -left, top, and nega‐
167              tive values for -right and -bottom.  Remember to subtract one in
168              the   latter  case;  e.g.  the  equivalent  of  -cropright=1  is
169              -right=-2.
170
171
172       -pad   If the rectangle you specify is not entirely  within  the  input
173              image, pamcut fails unless you also specify -pad.  In that case,
174              it pads the output with black up to the edges you specify.   You
175              can  use  this  option  if  you need to have an image of certain
176              dimensions and have an image of arbitrary dimensions.
177
178              pnmpad also adds borders to an  image,  but  you  specify  their
179              width directly.
180
181              pamcomp  does  a  more  general  form of this padding.  Create a
182              background image of the frame dimensions and overlay the subject
183              image  on  it.  You can use options to have the subject image in
184              the center of the frame or against any edge and make the padding
185              any  color  (the  padding  color  is the color of the background
186              image).
187
188
189       -verbose
190              Print information about the processing to Standard Error.
191
192
193

SEE ALSO

195       pnmcrop(1), pamdice(1), pamcomp(1), pnmpad(1), pnmcat(1),  pgmslice(1),
196       pnm(1)
197
198

HISTORY

200       pamcut  was  derived from pnmcut in Netpbm 9.20 (May 2001).  It was the
201       first Netpbm program adapted to the  new  PAM  format  and  programming
202       library.
203
204       The  predecessor pnmcut was one of the oldest tools in the Netpbm pack‐
205       age.
206
207
208

AUTHOR

210       Copyright (C) 1989 by Jef Poskanzer.
211

DOCUMENT SOURCE

213       This manual page was generated by the Netpbm tool 'makeman'  from  HTML
214       source.  The master documentation is at
215
216              http://netpbm.sourceforge.net/doc/pamcut.html
217
218netpbm documentation            04 October 2019          Pamcut User Manual(0)
Impressum