NAMEr.out.ppm - Converts a GRASS raster map to a PPM image file at the pixel resolution of the currently defined region.
SYNOPSISr.out.ppm r.out.ppm help r.out.ppm [-qG] input=name [output=name] [--verbose] [--quiet] Flags: -q Run quietly -G Output greyscale instead of color --verbose Verbose module output --quiet Quiet module output Parameters: input=name Name of input raster map output=name Name for new PPM file (use '-' for stdout) Default: .ppm
DESCRIPTIONr.out.ppm converts a GRASS raster map into a PPM image at the pixel resolution of the CURRENTLY DEFINED REGION. To get the resolution and region settings of the raster map, run: g.region -p rast=[mapname] before running r.out.ppm. By default the PPM file created is 24-bit color, rawbits storage. You can use the -G flag to force r.out.ppm to output an 8-bit greyscale instead. The greyscale conversion uses the NTSC conversion: Y = .30*Red + .59*Green + .11*Blue One pixel is written for each cell value, so if ew_res and ns_res differ, the aspect ratio of the resulting image will be off.
NOTESA few ppm file comments are written: the name of the GRASS raster map, resolution, etc. Although these are perfectly legal, I've found one PD image utility that chokes on them, so if you need a commentless PPM file, use 'out=- > outfile.ppm'. (When sending output to stdout, no comments are written.)
HINTSYou can create a PNG image with NULL values represented by a transparent background by using the PNG driver with GRASS_TRANSPARENT set to TRUE. Alternatively, you can use the pnmtopng program from netpbm to do this: r.out.ppm raster pnmtopng -transparent white raster.ppm > raster.png
SEE ALSOd.out.png r.out.ascii r.out.mpeg r.out.png r.out.ppm3 r.out.tiff
AUTHORBill Brown, UIUC Last changed: $Date: 2008-05-16 21:09:06 +0200 (Fri, 16 May 2008) $ Full index (C) 2003-2010 GRASS Development Team R.OUT.PPM(1)