Cropping large image exceptionally slow (20mins+)

[SamC]

So this image is a hefty 4000 x 3000 and I tried to crop out an area 2500 x 1500. The little red 'saving' icon appears when I click 'Apply', then just spins, and spins, and spins... for the past 20mins. I get the feeling it's not liking this too much.

My auto generated images work ok on page refresh, a bit slow the first time (I believe the cached one is used after that) but this site is only going to have about 10 full size images total so space is not my concern, I will use larger images for larger resolutions, smaller ones for tablet/mobile with some inline CSS background images using PHP variables holding the different image sizes (and a class that only populates in a div if there is actually an image present, set to 1 image or null) i.e.

// main.php
    <?php
        if ($page->mainImage) {
            $className = 'main-image-wrapper';

            $options = array(
                'cropping' => 'center'
            );
			
            // the original image sizes will be anything up to 4000 x 3000 but at least 768px wide
            $small = $page->mainImage->size(768, 280, $options);
            $large = $page->mainImage->size(1000, 350, $options);

            $smallBgImage = $small->url;
            $largeBgImage = $large->url;

        }
    ?>

    <style type="text/css">
        #main-image-wrapper {
            background-image: url('<?php echo $smallBgImage ?>');
        }

            @media screen and (min-width: 768px) {
                #main-image-wrapper {
                    background-image: url('<?php echo $largeBgImage ?>');
                }
            }
        }
    </style>

Anyway, the API generated images don't take 'too' long, not fast but bearable. However, the slow cropping in the admin area might be an issue. Is there a way to speed this up other than using smaller images?

ImageMagick perhaps? Thanks.

 

--EDIT--

To add, this is on localhost with PW v3 (not sure exact version off hand). Thanks.

Edited October 19, 2016 by SamC
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