1RASCAT(1NCARG) NCAR GRAPHICS RASCAT(1NCARG)
2
6 Rascat - concatenate, convert raster files
7
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... ]
13
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.
22 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.
27 Currently, only 8-bit-indexed and 24-bit-direct color encodings are
29 supported.
30 See ras_formats(5NCARG) for a list of supported image formats.
32
34 -help Print a usage message and exit.
35 -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.
42 -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.
49 -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.
55 -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.
63 -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.
70 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.
75 -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.
81 -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.
90 -verbose
92 Tells rascat to operate in verbose mode.
93 -Version
95 Print rascat's version number and then exit.
96 -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.
103 -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.
110
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.
116
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:
120 % rascat file1.nrif file2.sun file3.xwd > file123.nrif
123 In this example the same files are converted and concatenated into a
125 sun file:
126 % rascat -ofmt sun file1.nrif file2.sun file3.xwd > file123.sun
129 The -ofmt option is necessary in this example because the first file
132 rascat encounters is an NRIF file.
133 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:
136 % rascat -window 512 512 0 0 foo.sun > foo.512x512.sun
139
141 rasgetpal(1NCARG), rasls(1NCARG), rassplit(1NCARG), rasview(1NCARG),
142 ras_formats(5NCARG), ras_palette(5NCARG)
143 Hardcopy: NCAR Graphics Fundamentals, UNIX Version
145
147 Aspect ratios are not preserved by the -resolution option.
148 Not all formats support both 8-bit and 24-bit encodings.
150 Indexed and direct color encodings cannot be mixed.
152
154 Copyright (C) 1987-2009
155 University Corporation for Atmospheric Research
156 The use of this Software is governed by a License Agreement.
158NCARG January 1993 RASCAT(1NCARG)