TK (And my Faulty Script) Eating Memory

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

I've written this subroutine to create bitmaps for me automatically. I am working with large number of fairly large jpegs (ie, 700 or 800 k). I call this routine on a loop of filenames, but I keep running out of memory. (I have 384 MB so this should'nt be a problem). Somewhere, something isn't going out of scope like I think it should...

use TK;
use TK::JPEG;

sub makeLittlePic {
    # 
    my $filename = shift;
    my $newFilename = shift;
    my $targetSize = shift;
    
    my $main = new MainWindow;
        
    my $jpgimg = $main -> Photo(-format    => 'jpeg',
                                    -file        => $filename);

    unless ($jpgimg->height() > $targetSize or $jpgimg->width() > $tar
+getSize) {
        $jpgimg->write( $newFilename );
        return 1;
    }
        
    my $newimg = $main -> Photo('-format'    => 'jpeg');
        
    if($jpgimg->height > $jpgimg->width) {
        $newimg->copy( $jpgimg, -subsample => int($jpgimg->height / $t
+argetSize) );
    } else {
        $newimg->copy( $jpgimg, -subsample => int($jpgimg->width / $ta
+rgetSize) );
    }
    
    $newimg->write( $newFilename );
    
    $main = undef;
    $jpgimg = undef;
    $newimg = undef;
    return 1;
}
[download]

Comment on TK (And my Faulty Script) Eating Memory Download Code

Replies are listed 'Best First'.
Re: TK (And my Faulty Script) Eating Memory by bbfu (Curate) on Jun 11, 2003 at 20:36 UTC
When you create a Tk::Image (the parent class of Tk::Photo) without specifying a name, it generates a unique name. Tk then keeps references to these images, whether you do or not, so that you can later specify just a name anywhere that Tk is expecting a Tk::Image (or child). You have to call `$image->delete()` to actually delete the image. See the docs for Tk::Image. bbfu Black flowers blossom Fearless on my breath	[reply] [d/l]
Re: TK (And my Faulty Script) Eating Memory by webfiend (Vicar) on Jun 11, 2003 at 20:32 UTC
Are you using Tk::JPEG to create thumbnail image files? It does seem like there would be more effective ways to go about it ;-). You might consider playing with the Image::Magick modules, especially Image::Magick::Thumbnail.	[reply]