ppmsvgalib(1)ppmsvgalib(1)NAMEppmsvgalib - display PPM image on Linux console using
Svgalib
SYNOPSISppmsvgalib [-mode=mode]
All options can be abbreviated to their shortest unique
prefix. You may use two hyphens instead of one to desig
nate an option. You may use either white space or an
equals sign between an option name and its value.
DESCRIPTIONppmsvgalib Display a PPM image on a Linux virtual console
using the Svgalib facility. Svgalib is a popular means of
displaying Graphics in Linux without the use of the X Win
dow System.
If you run ppmsvgalib with a version of Svgalib earlier
than 1.9, you must run it as superuser, as Svgalib uses
superuser-only facilities to access the console hardware.
Newer Svgalib has its own device driver, so you need only
properly permissions on a device special file to access
the console.
ppmsvgalib is not capable of using color mapped video
modes. These are the old video modes that are usually
called "8 bit" color modes.
ppmsvgalib is a bare displayer. It won't do any manipula
tion of the image and is not interactive in any way. If
you want a regular interactive graphics viewer that uses
Svgalib, try zgv (not part of Netpbm).
To exit ppmsvgalib while it is displaying your image, send
it a SIGINTR signal (normally, this means "hit control
C").
ppmsvgalib draws a white border around the edges of the
screen. It does this to help you isolate problems between
the image you're displaying and the facilities you're
using to display it.
(Note: if the image you're displaying reaches the edges of
the screen, it will replace the white border).
ppmsvgalib places the image in the center of the screen.
If your image is too big to display in the video mode you
selected, ppmsvgalib fails. You can use pamcut or pnmcut
to cut out a part of the image to display or use pnmscale
to shrink the image to fit.
If you want to play with ppmsvgalib, ppmcie is a good way
to generate a test image.
To be pedantic, we must observe that ppmsvgalib displays a
PPM image in the correct colors only if the display has a
transfer function which is the exact inverse of the gamma
function that is specified in the PPM specification.
Happily, most CRT displays are pretty close.
Running the PPM image through pnmgamma can help cause
ppmsvgalib to display the correct colors.
OPTIONS
-mode=mode
This tells ppmsvgalib what video mode to use. mode
is the Svgalib video mode number. You can get a
list of all the video modes and their Svgalib video
mode numbers with the program vgatest that is pack
aged with Svgalib. (Unfortunately, the various
interesting programs that are packaged with Svgalib
are typically not installed on systems that have
the Svgalib library installed).
In practice, there are probably only two modes
you'll ever care about: 25 is the standard SVGA
direct color mode, which is 1024 columns by 768
rows with 8 bit red, green, and blue components for
each pixel and no fancy options. 28 is the same,
but with the popular higher resolution of 1280 x
1024.
But if you have an older video controller (with
less than 4MB of memory), those modes aren't avail
able and you might like mode 19, which is 640 x 480
and takes less than a megabyte of video memory.
This is a standard VGA video mode.
SEE ALSOpamcut(1), pnmcut(1), pnmscale(1), ppmcie(1), ppm(5),
zgv(1), Svgalib, vgatest(1)AUTHOR
By Bryan Henderson, January 2002.
Contributed to the public domain.
06 January 2002 ppmsvgalib(1)
