I have a script for an 'article manager' web-based interface, where the manager uploads a given image to the server.

Before writing the image to the server, which is to be embedded into the article it is associated with, its width and height are checked:

  use Image::Magick;
  ...
  # Check and change image height if necessary
  my ($height,$width);
  ($height,$width) = $image->GetAttribute('height','width');
  if ( $height > 300 ) {
    my ($newheight,$newwidth);
    $newheight = 300;
    $newwidth = ($width*$newheight)/$height;
    $image->Scale('height'=>$newheight,'width'=>$newwidth);
  }
  
  # Check and change image width if necessary
  ($height,$width) = $image->GetAttribute('height','width');
  if ( $width > 250 ) {
    my ($newheight,$newwidth);
    $newwidth = 250;
    $newheight = ($height*$newwidth)/$width;
    $image->Scale('width'=>$newwidth,'height'=>$newheight);
  }
[download]

No problem with that code (save it being repetitive in parts, which is necessary as I need to have verbose code for the client, not necessarily 'clean, Perlish' code).

However, I also need to check/change image resolution, which from my understanding should be able to be done like so:

  # Adjust Resolution if necessary
  $image->SetAttribute('units'=>'PixelsPerInch');
  my ($xrez,$yrez) = $image->GetAttribute('x-resolution',
'y-resolution');
  if ($xrez > 72 || $yrez > 72) {
    $image->SetAttribute('density'=>'72x72');
  }
[download]

But alas, the image is written to the server in the following steps with the initial resolution, which could be above 72 and is undesirable.

Embedding print statements before the resolution block of code yields, say for an example image:

x-resolution is 300
y-resolution is 300
[download]

After the resolution block, the same print statement yields:

x-resolution is 72
y-resolution is 72
[download]

Which would lead one to believe the transformation occurred, although it did not (the image on the server retains the original resolution).

Have any fellow monks run into such problems before?

--
notsoevil
--
Jeremiah 49:32 - And their camels shall be a booty. . .

---

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