Hi,

I decided to use Image::Magick to create thumbnails for images uploaded by an end user.

I'm not sure what I'm missing here, but my purpose of creating a thumbnail is to save bandwidth in the future. I thought it would be logic that if the thumbnail is almost 70% smaller then the original size, then the image size should dramatically be smaller.

Heres a part of my script that uploads an file that was attached via browser and then creates a thumbnail. 
if ($chart_name ne "") {
my ($Bytes, $Buffer);


    open OUTPUT, ">", $chart_f or die "Can't open: $!";
    binmode OUTPUT; #binmode since I'm on Windows
          while ($Bytes = read($fh, $Buffer,1024)) {
                print OUTPUT $Buffer;
          }

    close OUTPUT or die "Can't close: $!";

use Image::Magick;
my $image = Image::Magick->new;
my $x = $image->Read($chart_f);

  $x = $image->Thumbnail(width=>240, height=>153);
  warn "$x" if "$x";

  $x = $image->Write($chart_thumb);
  warn "$x" if "$x";

}

[download]
Everything works for me, the upload and the creation of the thumbnail. However, when checking the file size of the thumbnail, I noticed that it was larger then the original. Can anyone explain to me why this is happening? Only reason I can think of is that Image::Magick adds other features to the image, thus creating it to be larger? I tried resizing an image so that its a thumbnail in Adobe Photoshop, and the filesize of the thumb was significantly lower.

Only other way I can think of is perhaps saving it as a different format other then png using Imagic::Magick? Perhaps a .gif?

Thanks for reading this post.

perleager 429

In reply to Image::Magick - Changing Quality? by perleager

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