> For the complete documentation index, see [llms.txt](https://trizen.gitbook.io/perl6-rosettacode/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://trizen.gitbook.io/perl6-rosettacode/programming_tasks/b/bitmap/read_an_image_through_a_pipe.md).

# Read an image through a pipe

Uses pieces from [Bitmap](https://rosettacode.org/wiki/Bitmap#Raku) and [Read a PPM file](https://rosettacode.org/wiki/Bitmap/Read_a_PPM_file#Raku) tasks. Included here to make a complete, runnable program.

Uses imagemagick convert to pipe the image in.

```perl
class Pixel { has UInt ($.R, $.G, $.B) }
class Bitmap {
    has UInt ($.width, $.height);
    has Pixel @.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
    }
}

sub getline ( $proc ) {
    my $line = '#'; # skip comment when reading a .png
    $line = $proc.out.get while $line.substr(0,1) eq '#';
    $line;
}

my $filename = './camelia.png';

my $proc = run 'convert', $filename, 'ppm:-', :enc('ISO-8859-1'), :out;

my $type = getline($proc);
my ($width, $height) = getline($proc).split: ' ';
my $depth = getline($proc);

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

$b.data = $proc.out.slurp.ords.rotor(3).map:
  { Pixel.new(R => .[0], G => .[1], B => .[2]) };

'./camelia.ppm'.IO.open(:bin, :w).write: $b.P6;
```

See [camelia image here](https://github.com/thundergnat/rc/blob/master/img/camelia.png).