1r.out.mpeg(1) Grass User's Manual r.out.mpeg(1)
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6 r.out.mpeg - Raster File Series to MPEG Conversion Program.
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9 raster
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12 r.out.mpeg
13 r.out.mpeg help
14 r.out.mpeg [-qc] view1=string[,string,...] [view2=string[,string,...]]
15 [view3=string[,string,...]] [view4=string[,string,...]] [out‐
16 put=string] [qual=integer]
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18 Flags:
19 -q Quiet - suppress progress report
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21 -c Convert on the fly, use less disk space (requires r.out.ppm with
22 stdout option)
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24 Parameters:
25 view1=string[,string,...]
26 Raster file(s) for View1
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28 view2=string[,string,...]
29 Raster file(s) for View2
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31 view3=string[,string,...]
32 Raster file(s) for View3
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34 view4=string[,string,...]
35 Raster file(s) for View4
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37 output=string
38 Name for output file Default: gmovie.mpg
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40 qual=integer
41 Quality factor (1 = highest quality, lowest compression) Options:
42 1-5 Default: 3
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45 r.out.mpeg is a tool for combining a series of GRASS raster files into
46 a single MPEG-1 (Motion Pictures Expert Group) format file. MPEG-1 is
47 a "lossy" video compression format, so the quality of each resulting
48 frame of the animation will be much diminished from the original raster
49 image. The resulting output file may then be viewed using your
50 favorite mpeg-format viewing program. MPEG-2 and MPEG-4 provide much
51 better quality animations.
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53 The user may define up to four "views", or sub-windows, to animate
54 simultaneously. e.g., View 1 could be rainfall, View 2 flooded areas,
55 View 3 damage to bridges or levees, View 4 other economic damage, all
56 animated as a time series. A black border 2 pixels wide is drawn around
57 each view. There is an arbitrary limit of 400 files per view (400 ani‐
58 mation frames). Temporary files are created in the conversion process,
59 so lack of adequate tmp space could also limit the number of frames you
60 are able to convert.
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62 The environment variable GMPEG_SIZE is checked for a value to use as
63 the dimension, in pixels, of the longest dimension of the animation
64 image. If GMPEG_SIZE is not set, the animation size defaults to the
65 rows & columns in the current GRASS region, scaling if necessary to a
66 default minimum size of 200 and maximum of 500. These size defaults
67 are overridden when using the -c flag (see below). The resolution of
68 the current GRASS region is maintained, independent of image size.
69 Playback programs have to decode the compressed data "on-the-fly",
70 therefore smaller dimensioned animations will provide higher frame
71 rates and smoother animations.
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73 UNIX - style wild cards may be used with the command line version in
74 place of a raster file name, but wild cards must be quoted.
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78 r.out.mpeg view1="rain[1-9]","rain1[0-2]" view2="temp*"
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81 If the number of files differs for each view, the view with the fewest
82 files will determine the number of frames in the animation.
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84 With -c flag the module converts "on the fly", uses less disk space by
85 using r.out.ppm with stdout option to convert frames as needed instead
86 of converting all frames to ppm before encoding. Only use when encod‐
87 ing a single view. Use of this option also overrides any size
88 defaults, using the CURRENTLY DEFINED GRASS REGION for the output size.
89 So be careful to set region to a reasonable size prior to encoding.
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91 A quality value of qual=1 will yield higher quality images, but with
92 less compression (larger MPEG file size). Compression ratios will vary
93 depending on the number of frames in the animation, but an MPEG pro‐
94 duced using qual=5 will usually be about 60% the size of the MPEG pro‐
95 duced using qual=1.
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98 MPEG images must be 16-pixel aligned for successful compression, so if
99 the rows & columns of the calculated image size (scaled, with borders
100 added) are not evenly divisible by 16, a few rows/columns will be cut
101 off the bottom & right sides of the image. The MPEG format is optimized
102 to recognize image MOTION, so abrupt changes from one frame to another
103 will cause a "noisy" encoding.
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106 This program requires the program mpeg_encode (aka ppmtompeg):
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108 MPEG-1 Video Software Encoder
109 (Version 1.3; March 14, 1994)
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111 Lawrence A. Rowe, Kevin Gong, Ketan Patel, and Dan Wallach Computer
112 Science Division-EECS, Univ. of Calif. at Berkeley
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114 Available from Berkeley: http://bmrc.berke‐
115 ley.edu/frame/research/mpeg/mpeg_encode.html
116 or as part of the netpbm package (ppmtompeg): http://netpbm.source‐
117 forge.net
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119 Playback may be done with many viewers; mpeg_encode's official compan‐
120 ion is mpeg_play available from Berkeley at ftp://mm-ftp.cs.berke‐
121 ley.edu/pub/multimedia/mpeg/play/ or a precompiled Debian package from
122 http://packages.debian.org/ucbmpeg-play (includes maintained source
123 code).
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125 Use of the -c flag requires the r.out.ppm GRASS module with the stdout
126 option.
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129 r.out.ppm
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132 Bill Brown, U.S. Army Construction Engineering Research Laboratories
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134 Last changed: $Date: 2005/12/12 14:53:40 $
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136 Full index
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140GRASS 6.2.2 r.out.mpeg(1)