The document describes a "miyagawanize" script that was created to add a "purple thing" to images, in order to be more like the expert Perl coder Tatsuhiko Miyagawa. It explains that the script uses OpenCV, Imager and Image::ObjectDetect modules to detect faces in an image, scale and overlay a purple image on the faces. Example code is provided to detect faces in an input image, process each face by scaling and overlaying the purple image, and writing the output image.

1. miyagawanize Yusukebe YAPC::Asia 2009 Lighting Talk

3. PURPLE THING

7. #!/usr/bin/perl use strict; use warnings; use Imager; use Image::ObjectDetect;

8. my $file = shift or die "image file path is required!"; my $image = Imager->new->read( file => $file ); my $cascade = './haarcascade_frontalface_alt2.xml'; my $detector = Image::ObjectDetect->new($cascade); my @faces = $detector->detect($file); my $purple_source = Imager->new->read(file => './purple.png'); my $aspect = 1.5;

9. for my $face (@faces) { my $purple = $purple_source->scale( xpixels => $face->{width} / $aspect, ypixels => $face->{height} / $aspect, ); $image->rubthrough( tx => $face->{width} / $aspect / 2 + $face->{x}, ty => $face->{height} / $aspect + $face->{y}, src => $purple, ); } $image->write( file => './output.jpg' );

10. DEMO

11. Let’s “miyagawanize”, And write a great code! Thanks to Tatsuhiko Miyagawa!!