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Delayed Image Variations Delays the creation of image variations until their individual URLs are loaded. Image variations being generated one-by-one: Background Normally when you create new image variations in a template file using any of the ProcessWire image resizing methods, all the new variations that are needed on a page will be created from the original Pageimage the next time the page is loaded in a browser. If there are a lot of images on the page then this could take a while, and in some cases the page rendering might exceed your max_execution_time setting for PHP. So you might like to have image variations be generated individually when they are requested rather than all at once. That way the page will render more quickly and the risk of a timeout is all but eliminated. But there can be problems with some implementations of this approach, such as with the (in)famous TimThumb script: It's not ideal to have PHP be involved in serving every image as this is needlessly inefficient compared to serving static assets. It's not good to allow arbitrary image sizes to be generated by varying URL parameters because you might want to restrict the maximum resolution an image is available at (e.g. for copyrighted images). If images are generated from URL parameters a malicious user could potentially generate thousands of images of slightly different dimensions and fill up all your disk space. The Delayed Image Variations module avoids these problems - it creates variations when their URLs are loaded but only allows the specific dimensions you have defined in your code. It does this by saving the settings (width, height and ImageSizer options) of every new Pageimage::size() call to a queue. The module intercepts 404s and if the request is to an image variation that doesn't exist yet but is in the queue it generates the variation and returns the image data. This only happens the first time the image is requested - after that the image exists on disk and gets loaded statically without PHP. Usage In most cases usage is as simple as installing the module, and you don't need to change anything in your existing code. However, there might be some cases where you don't want the creation of a particular image variation to be delayed. For example, if you created a variation in your code and then immediately afterwards you wanted to get information about the variation such as dimensions or filesize. $resized = $page->image->width(600); echo $resized->height; echo $resized->filesize; This wouldn't work because the actual creation of the resized image hasn't happened yet and so that information won't be available. So in these cases you can set a noDelay option to true in your ImageSizer options and Delayed Image Variations will skip over that particular resizing operation. $resized = $page->image->width(600, ['noDelay' => true]); echo $resized->height; echo $resized->filesize; For advanced cases there is also a hookable method that you can return false for if you don't want a delayed variation for any particular resizing operation. Example: $wire->addHookAfter('DelayedImageVariations::allowDelayedVariation', function(HookEvent $event) { /** @var Pageimage $pageimage */ $pageimage = $event->arguments(0); // The Pageimage to be resized $width = $event->arguments(1); // The width supplied to Pageimage::size() $height = $event->arguments(2); // The height supplied to Pageimage::size() $options = $event->arguments(3); // The options supplied to Pageimage::size() // Don't delay variations if the Pageimage belongs to a page with the product template if($pageimage->page->template == 'product') $event->return = false; }); 404 handling For Delayed Image Variations to work your .htaccess file needs to be configured so that ProcessWire handles 404s. This is the default configuration so for most sites no change will be needed. # ----------------------------------------------------------------------------------------------- # 2. ErrorDocument settings: Have ProcessWire handle 404s # # For options and optimizations (O) see: # https://processwire.com/blog/posts/optimizing-404s-in-processwire/ # ----------------------------------------------------------------------------------------------- ErrorDocument 404 /index.php ProCache If you are using ProCache then make sure it is not configured to cache the 404 page or else PHP will not execute on 404s and queued image variations will not be generated. Generate queued variations Before launching a new website you might want to pre-generate all needed image variations, so no visitor will have to experience a delay while a variation is generated. To queue up the image variations needed for your site you will need to visit each page of the website one way or another. You could do this manually for a small site but for larger sites you'll probably want to use a site crawler tool such as Xenu's Link Sleuth. This may generate some image variations but it's likely that some other variations (e.g. within srcset attributes) will not be requested and so will remain queued. To generate all currently queued variations there is a button in the module config: This will search the /site/assets/files/ directory for queue files and render the variations. https://github.com/Toutouwai/DelayedImageVariations https://processwire.com/modules/delayed-image-variations/

I'm using since 2017 some self developed non public module to upload and manage images via Adobe Scene7. So we don't save images on the filesystem. Since some weeks I get this error in the admin panel. Can I hide this in some way or with some hook? It affects nothing in my setup.

These issues should be fairly easy for any intermediate to advanced ProcessWire developer to answer. I'm new to PHP and relatively new to ProcessWire and just need a bit of help. What I'm trying to do is bring in a couple of cards from my Projects page to display on my home page. I finally got the code right to bring in the cards but right now they're using my original images instead of my resized "variations". So firstly, I would like to know how to reference the variations of my images instead of using the original. Secondly, I need to grab only four of the cards from the Project page and not import in all ten. It should be just two small changes to my code to do these things (I would imagine). Here is the code I currently have for that section: <?php // https://processwire.com/api/arrays/ // check if the array of images has items if (count($pages->get("/projects/")->images)) : // get array of images from the field $images = $pages->get("/projects/")->images; $count = 0; // iterate over each one foreach ($images as $image) : $count++; $sectionText = $pages->get("/projects/")->get("paragraph_$count"); $img = $image; $buttonCode = $pages->get("/projects/")->get("url_$count"); ?> <span id="card<?php echo $count?>" class="card"> <img class="cardThumb" src="<?php echo $img->url; ?>" alt="<?php echo $image->description; ?> Thumbnail" /> <div class="cardBody"> <div class="cardText"> <h2><?php echo $img->description; ?></h2> <?php echo $sectionText; ?> </div> <div class="primaryBtn"> <a href="https://www.paypal.com/donate?hosted_button_id= <?php echo $buttonCode; ?> &source=url"> <button> <i class="fas fa-donate"></i> Donate </button> </a> </div> </div> </span> <?php endforeach; endif; ?> Thanks in advance for any help!

Hello I'm working on a project that use PW as backend CMS. PW serves formatted data of each page but the engine simply generates json from pagearray. I would like to set one or more variations on images, so I think it would be useful if there were a field to set possible variations... even with overrides!

I created this module a while ago and never got around to publicising it, but it has been outed in the latest PW Weekly so here goes the support thread... Unique Image Variations Ensures that all ImageSizer options and focus settings affect image variation filenames. Background When using methods that produce image variations such as Pageimage::size(), ProcessWire includes some of the ImageSizer settings (height, width, cropping location, etc) in the variation filename. This is useful so that if you change these settings in your size() call a new variation is generated and you see this variation on the front-end. However, ProcessWire does not include several of the other ImageSizer settings in the variation filename: upscaling cropping, when set to false or a blank string interlace sharpening quality hidpi quality focus (whether any saved focus area for an image should affect cropping) focus data (the top/left/zoom data for the focus area) This means that if you change any of these settings, either in $config->imageSizerOptions or in an $options array passed to a method like size(), and you already have variations at the requested size/crop, then ProcessWire will not create new variations and will continue to serve the old variations. In other words you won't see the effect of your changed ImageSizer options on the front-end until you delete the old variations. Features The Unique Image Variations module ensures that any changes to ImageSizer options and any changes to the focus area made in Page Edit are reflected in the variation filename, so new variations will always be generated and displayed on the front-end. Installation Install the Unique Image Variations module. In the module config, set the ImageSizer options that you want to include in image variation filenames. Warnings Installing the module (and keeping one or more of the options selected in the module config) will cause all existing image variations to be regenerated the next time they are requested. If you have an existing website with a large number of images you may not want the performance impact of that. The module is perhaps best suited to new sites where image variations have not yet been generated. Similarly, if you change the module config settings on an existing site then all image variations will be regenerated the next time they are requested. If you think you might want to change an ImageSizer option in the future (I'm thinking here primarily of options such as interlace that are typically set in $config->imageSizerOptions) and would not want that change to cause existing image variations to be regenerated then best to not include that option in the module config after you first install the module. https://github.com/Toutouwai/UniqueImageVariations https://modules.processwire.com/modules/unique-image-variations/

Hi all, Just wondering if someone with a bit more PW knowledge than me could give a run down of what this method actually does and how its achieved. I get that it rebuilds image variations but based on what settings? If I wanted to rebuild all the websites image variations but at say a reduced image quality can this be set somewhere globally that this method would take into account? For some context I have built a fairly simple module to delete all the image variations connected to any FieldtypeImage which is being used on the website, for the most part this works quite well. As I was quite happy with how that turned out I figured I would give the module another option to rebuild the images also. So there would be a 'Remove' and 'Rebuild' button on the modules config page. The idea being that I could use this tool to delete all the image variations, update some global settings then regenerate them all but currently it doesn't appear to do that. I assume this is either because my codes borked or im misunderstanding something fundamental about how rebuildVariations() works.

Hi all, I am working on a site which involves a lot of image upload fields, 99% of the time it works perfectly but I have noticed that every so often image variations will be missing. Like the original uploaded image is fine but maybe 1 or 2 out of the variations is just blank. The variation files will appear within the assets folder but they will be just in name only without any actual image content. Since its quite a random thing I am finding it rather difficult to figure out why this happens? Any ideas?

Hello, since the new Reno Theme for PW 2.7, where can I find the image variations (rendered sizes by API or other modules)? If so and it won't come back: How can I remove all variations of an image with a single click? Thanks!