1RASCAT(1NCARG)                   NCAR GRAPHICS                  RASCAT(1NCARG)
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NAME

6       Rascat - concatenate, convert raster files
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SYNOPSIS

9       rascat [ -help ] [ -ifmt format ] [ -ira algorithm ] [ -ofmt format ] [
10       -output file ] [ -resolution resolution ] [ -rgbscale scale-factor ]  [
11       -scale scale-factor ] [ -verbose ] [ -Version ] [ -window nx ny x y ] [
12       -pal palette_file ] [ -|file...  ]
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DESCRIPTION

15       rascat reads each file in sequence and copies its contents to the stan‐
16       dard  output performing any format conversion and data massaging neces‐
17       sary as specified by the command  line  options.   By  default,  rascat
18       determines  the format of a file by looking at the file name extension.
19       If there are multiple files input into rascat with varying file formats
20       rascat  will perform format conversion such that the resulting concate‐
21       nated file will be in the format of the first file processed.
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23       Input files must all have the same spatial resolution and have the same
24       depth; 8-bit and 24-bit files may not be intermixed. Furthermore, if an
25       input file contains multiple images each image in that file  must  have
26       the same spatial resolution and be of the same depth.
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28       Currently,  only  8-bit-indexed  and  24-bit-direct color encodings are
29       supported.
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31       See ras_formats(5NCARG) for a list of supported image formats.
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OPTIONS

34       -help  Print a usage message and exit.
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36       -ifmt format
37              Specify the input file format.  format is one of the  file  name
38              extensions  discussed  in  ras_formats(5NCARG) (without the ".",
39              e.g.  xwd).  When this option is specified file name  extensions
40              are  not  necessary and are ignored if present.  All input files
41              must have the same format.
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43       -ira algorithm
44              Specify the image resampling algorithm to be  used  when  either
45              the  -scale  or  the  -resolution  command  line option is used.
46              algorithm may be either  NN,  indicating  a  "nearest  neighbor"
47              algorithm,  or  BL,  indicating  a "bilinear interplation" algo‐
48              rithm. The default is to do "nearest neighbor" interpolation.
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50       -ofmt format
51              Specify the output file format.  format is one of the  aforemen‐
52              tioned  file  name  extensions.  If used in conjunction with the
53              -output option the output file name requires no  name  extension
54              and is ignored if present.
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56       -output file
57              Specify  an ouput file name and possibly an implicit output for‐
58              mat. By default rascat writes to the standard output. When  this
59              option  is  used output is written to file.  If the -ofmt option
60              is not specified file must have a file name extension recognized
61              by rascat.  In which case the file name extension will determine
62              the output format.
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64       -resolution resolution
65              Resample the spatial resolution of input imagery to  resolution,
66              where  resolution  is  the  number of pixels in the x direction,
67              followed by an x, followed by the number  of  pixels  in  the  y
68              direction,  with  no  intervening  spaces. For example, 512x512,
69              specifies a 512 by 512 pixel resolution.
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71              Warning: Aspect ratios are not preserved by this option. If  the
72              resolution  of  your  input imagery has a different aspect ratio
73              then that specified by resolution the resultant  image  will  be
74              distorted.
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76       -rgbscale scale-factor
77              Specify  a  floating  point  scaling factor, scale-factor, to be
78              applied to all the color  intensities  contained  in  the  input
79              files.  This option may be fairly computationally expensive with
80              24-bit-direct encoded imagery.
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82       -scale scale-factor
83              Specify a uniform, floating-point scaling factor to  be  applied
84              to  the spatial resolution of the input files. Unlike the -reso‐
85              lution option this option  guarantees  to  preserve  the  aspect
86              ratio  of your imagery. For example, setting scale-factor to 0.5
87              causes your imagery to be resampled to one fourth of its  origi‐
88              nal spatial resolution. If its original resolution was 1024x1024
89              the resultant resolution would be 512x512.
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91       -verbose
92              Tells rascat to operate in verbose mode.
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94       -Version
95              Print rascat's version number and then exit.
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97       -window nx ny x y
98              Specify a subregion of the input imagery to  be  extracted.  The
99              area  outside the rectangular subregion defined by nx, ny, x and
100              y is discarded.  x and y specify the position of the  upper-left
101              corner  of  the  rectangle.   nx  and ny specify the rectangle's
102              width and height, respectively.
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104       -pal palette_file
105              Set the palette for  the  output  rasterfile  from  palettefile,
106              which  can  be  either  an HDF-type palette with an extension of
107              ".pal", or a textual palette with an extension  of  ".txt".  See
108              ras_palette(5NCARG)  for  documentation  on  the  formats.  This
109              option applies to indexed-color imagery only.
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ENVIRONMENT

112       NCARG_TMP
113              If set, this environment variable contains a directory  path  to
114              be  used  for  temporary  files.  On most systems the default is
115              /tmp.  On some systems the default is /usr/tmp.
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EXAMPLES

118       In the following example a NRIF file, a Sun raster image  file,  and  a
119       XWD file are concatenated and converted into a single NRIF file:
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122              % rascat file1.nrif file2.sun file3.xwd > file123.nrif
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124       In  this  example  the same files are converted and concatenated into a
125       sun file:
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128              % rascat -ofmt sun file1.nrif file2.sun file3.xwd > file123.sun
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131       The -ofmt option is necessary in this example because  the  first  file
132       rascat encounters is an NRIF file.
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134       Finally,  in  this  example  the upper left 512 by 512 rectangle of the
135       file foo.sun is extracted and written to the file foo.512x512.sun:
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138              % rascat -window 512 512 0 0 foo.sun > foo.512x512.sun
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SEE ALSO

141       rasgetpal(1NCARG),  rasls(1NCARG),  rassplit(1NCARG),  rasview(1NCARG),
142       ras_formats(5NCARG), ras_palette(5NCARG)
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144       Hardcopy: NCAR Graphics Fundamentals, UNIX Version
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CAVEATS

147       Aspect ratios are not preserved by the -resolution option.
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149       Not all formats support both 8-bit and 24-bit encodings.
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151       Indexed and direct color encodings cannot be mixed.
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154       Copyright (C) 1987-2009
155       University Corporation for Atmospheric Research
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157       The use of this Software is governed by a License Agreement.
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161NCARG                            January 1993                   RASCAT(1NCARG)
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