What seems to be happening is that 1/4 to 1/2 of the image data is being dropped prior to finishing the thumbnail file.
Does that imply that the extent of corruption varies depending on the image? (Or simply that you're not sure what the real amount of lossage is?)

If it varies with the image, then maybe you should take a closer look at this line in your code: 

if ($opsys eq "dos") { binmode THUMB; }

[download]
Are you sure that "$opsys" has been set appropriately? (Why aren't you just using "$^O" ?)

Apart from that, I don't know about the GD::Image "jpeg" method... what does it mean to pass it a value of "75"?

In reply to Re: Corrupted data problem in copyResampled using GD.pm by graff
in thread Corrupted data problem in copyResampled using GD.pm by brianviehland

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