Bitmap/PPM conversion through a pipe: Difference between revisions

=={{header|Perl 6}}==

<lang perl6>#!/usr/bin/env perl6

# Reference:

# https://rosettacode.org/wiki/Bitmap/Write_a_PPM_file#Perl_6

use v6;

class Pixel { has uint8 ($.R, $.G, $.B) }

class Bitmap {

has UInt ($.width, $.height);

has Pixel @!data;

method fill(Pixel $p) {

@!data = $p.clone xx ($!width*$!height)

}

method pixel(

$i where ^$!width,

$j where ^$!height

--> Pixel

) is rw { @!data[$i*$!height + $j] }

method data { @!data }

}

role PPM {

method P6 returns Blob {

"P6\n{self.width} {self.height}\n255\n".encode('ascii')

~ Blob.new: flat map { .R, .G, .B }, self.data

}

}

my Bitmap $b = Bitmap.new(width => 125, height => 125) but PPM;

for flat ^$b.height X ^$b.width -> $i, $j {

$b.pixel($i, $j) = Pixel.new: :R($i*2), :G($j*2), :B(255-$i*2);

}

my $proc = run '/usr/bin/convert','-','output_piped.jpg', :in, :out;

$proc.in.write: $b.P6;

$proc.in.close;

</lang>

{{out}}

<pre>file output_piped.jpg

output_piped.jpg: JPEG image data, JFIF standard 1.01, aspect ratio, density 1x1, segment length 16, baseline, precision 8, 125x125, frames 3</pre>