Perl GD/Pixel manipulation
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< Perl GD
Revision as of 10:19, 23 January 2011 by Heth (talk | contribs) (New page: Playing with pixels. The script below makes this png picture. thumb|400px|Greyscale from 0 to 255 <source lang=perl> #!/usr/bin/perl use GD; use GD::Image; # crea...)
Playing with pixels. The script below makes this png picture.
#!/usr/bin/perl
use GD;
use GD::Image;
# create a new image
$im = new GD::Image(640,480);
#Grey scale
my @grey;
for (my $i = 0; $i <=255; $i++) {
$grey[$i] = $im->colorAllocate($i,$i,$i);
}
print "Allocated ", $#grey+1, " colors\n";
for( my $i=0; $i<=640-1 ;$i++ ) {
for( my $j=0; $j<=480-1;$j++ ) {
$im->setPixel($i,$j,@grey[ ($i+$j) % 256 ]);
#$im->setPixel($i,$j, $c[($i+$j)%4]);
}
}
print "Der er ialt ", $im->colorsTotal(), " farver\n";
# Convert the image to PNG and save it.
open FILE,'> C:\temp\heth.png';
binmode FILE;
print FILE $im->png;