File Coverage

blib/lib/Image/libsiftfast.pm

Criterion	Covered	Total	%
statement	15	50	30.0
branch	0	4	0.0
condition	1	2	50.0
subroutine	5	7	71.4
pod	3	3	100.0
total	24	66	36.3

package Image::libsiftfast;
use strict;
use warnings;
use File::Which qw(which);
use Imager;

our $VERSION = '0.03';

sub new {
    my $class = shift;
    my $self  = bless {
        siftfast_path => which("siftfast") || undef,
        imager => Imager->new,
        @_,
    }, $class;
    return $self;
}

sub convert_to_pnm {
    my $self = shift;
    my $file = shift;

    my $imager = $self->{imager};
    $imager->read( file => $file ) or die $imager->errstr;
    my $new = $imager->convert( preset => 'grey' );
    $file =~ s/jpg/pnm/;
    $new->write( file => $file, type => "pnm", pnm_write_wide_data => 1 )
        or die($!);
    return $file;
}

sub extract_keypoints {
    my $self     = shift;
    my $pnm_file = shift;

    my $siftfast_path = $self->{siftfast_path};
    my @stdout        = `$siftfast_path < $pnm_file 2>&1`;

    my $stderr_message = shift @stdout;
    $stderr_message .= shift @stdout;
    my ($image_size)
        = $stderr_message =~ /Finding keypoints \(image ([^\)]+)\).../g;
    my ( $keypoint_num, $elapsed )
        = $stderr_message =~ /(\d+) keypoints found in ([0-9.]+) seconds./g;

    my @array = map { chomp $_; $_ } @stdout;
    shift @array;    # remove first line;
    my $return_string = join( "\n", @array );

    my @keypoints;
    for ( split "\n\n", $return_string ) {
        my @rec = split "\n", $_;
        my @array;
        for (@rec) {
            my @f = split " ", $_;
            push @array, @f;
        }
        my $X           = shift @array;
        my $Y           = shift @array;
        my $scale       = shift @array;
        my $orientation = shift @array;
        my $vector      = \@array;

        push @keypoints,
            {
            frames => {
                X           => $X,
                Y           => $Y,
                scale       => $scale,
                orientation => $orientation,
            },
            vector => $vector,
            };
    }

    return {
        keypoint_num => $keypoint_num,
        elapsed      => $elapsed,
        image_size   => $image_size,
        keypoints    => \@keypoints,
    };
}

1;
__END__