Hough transform: Difference between revisions

Rename Perl 6 -> Raku, alphabetize, minor clean-up
m (→‎{{header|Perl}}: corrected read of existing image)
(Rename Perl 6 -> Raku, alphabetize, minor clean-up)
Line 479:
<pre>java HoughTransform pentagon.png JavaHoughTransform.png 640 480 100</pre>
<br style="clear:both" />
 
 
=={{header|Julia}}==
Line 641 ⟶ 640:
 
* see [[Example:Hough transform/MATLAB]]
 
 
=={{header|Perl}}==
Line 685 ⟶ 683:
$ht->write(file => 'hough_transform.png');
</lang>
 
=={{header|Perl 6}}==
The <code>GD</code> module the output palette to 255 colors, so only transform darker pixels in the image.
{{trans|Perl}}
<lang perl6>use GD;
 
my $filename = 'pentagon.ppm';
my $in = open($filename, :r, :enc<iso-8859-1>);
my ($type, $dim, $depth) = $in.lines[^3];
my ($xsize,$ysize) = split ' ', $dim;
 
my ($width, $height) = 460, 360;
my $image = GD::Image.new($width, $height);
 
my @canvas = [255 xx $width] xx $height;
 
my $rmax = sqrt($xsize**2 + $ysize**2);
my $dr = 2 * $rmax / $height;
my $dth = π / $width;
 
my $pixel = 0;
my %cstore;
for $in.lines.ords -> $r, $g, $b {
$pixel++;
next if $r > 130;
 
my $x = $pixel % $xsize;
my $y = floor $pixel / $xsize;
 
(0..^$width).race.map: -> $k {
my $th = $dth*$k;
my $r = ($x*cos($th) + $y*sin($th));
my $iry = ($height/2 + ($r/$dr).round(1)).Int;
my $c = '#' ~ (@canvas[$iry][$k]--).base(16) x 3;
%cstore{$c} = $image.colorAllocate($c) if %cstore{$c}:!exists;
$image.pixel($k, $iry, %cstore{$c});
}
 
my $png_fh = $image.open("hough-transform.png", "wb");
$image.output($png_fh, GD_PNG);
$png_fh.close;</lang>
See [https://github.com/thundergnat/rc/blob/master/img/hough-transform.png Hough Transform] (offsite .png image)
 
=={{header|Phix}}==
Line 833 ⟶ 788:
=={{header|Racket}}==
* see [[Example:Hough transform/Racket]]
 
=={{header|Perl 6Raku}}==
(formerly Perl 6)
The <code>GD</code> module the output palette to 255 colors, so only transform darker pixels in the image.
{{trans|Perl}}
<lang perl6>use GD;
 
my $filename = 'pentagon.ppm';
my $in = open($filename, :r, :enc<iso-8859-1>);
my ($type, $dim, $depth) = $in.lines[^3];
my ($xsize,$ysize) = split ' ', $dim;
 
my ($width, $height) = 460, 360;
my $image = GD::Image.new($width, $height);
 
my @canvas = [255 xx $width] xx $height;
 
my $rmax = sqrt($xsize**2 + $ysize**2);
my $dr = 2 * $rmax / $height;
my $dth = π / $width;
 
my $pixel = 0;
my %cstore;
for $in.lines.ords -> $r, $g, $b {
$pixel++;
next if $r > 130;
 
my $x = $pixel % $xsize;
my $y = floor $pixel / $xsize;
 
(0..^$width).race.map: -> $k {
my $th = $dth*$k;
my $r = ($x*cos($th) + $y*sin($th));
my $iry = ($height/2 + ($r/$dr).round(1)).Int;
my $c = '#' ~ (@canvas[$iry][$k]--).base(16) x 3;
%cstore{$c} = $image.colorAllocate($c) if %cstore{$c}:!exists;
$image.pixel($k, $iry, %cstore{$c});
}
 
my $png_fh = $image.open("hough-transform.png", "wb");
$image.output($png_fh, GD_PNG);
$png_fh.close;</lang>
See [https://github.com/thundergnat/rc/blob/master/img/hough-transform.png Hough Transform] (offsite .png image)
 
=={{header|Ruby}}==
10,333

edits