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Shopify Design Shopify themes, liquid, logos, and UX. Shopify Community : Shopify Discussion : Shopify Design : Lazy Loading Videos. Options Subscribe to RSS Feed Mark Topic as New Mark Topic as Read Float this Topic for Current User Bookmark Subscribe Mute Printer Friendly Page. Lazy Loading Videos.

Mark as New Bookmark Subscribe Mute Subscribe to RSS Feed Permalink Print Report Inappropriate Content. Is there a way i can add lazyloading to a product gallery video? ive been getting a loading speed of 30secs on my product page, while 3 secs on my homepage. ive tried looking for a fix, but all i got was how to apply lazy loading to images.

Im using Debutify. Labels: Labels: Shop Performance Troubleshooting. Accepted Solutions 2. Shopify Partner. This is an accepted solution. You need a Shopify expert to help you with your theme!

In response to JohnDx. All forum topics Previous Topic Next Topic Next topic. Replies 4 4. In response to OpenThinking. Ive found Lozad. js to be what i wanted, thank you! if i dont understand how to use the CDN install, i use a youtube url ill just get back to the original solution of using preload method.

im applying the video where you add pictures for products, no external apps or description. Thank you! This has somewhat improved the speed, but it looks like the youtube player is the main issue.

I checked on PageSpeed Insights Unused JavaScripts youtube. com file "base. js is taking around KiB www-embed-player. js youtube again KiB www-widgetapi.

js yt 50 KiB Unused css www-player. css yt 60 KiB At this point i'm going to either try remove the video Url and upload a downloaded version, or remove these codes to see if i'm using a different type of player. Post Reply. Community Blog Articles Navigating the Virtual Aisles: Crafting an Intuitive and Engaging Online Sh By Ollie Feb 13, Dropshipping in Europe with GOGETTERS.

By Arno Feb 9, By Jacqui Feb 2, This is the fastest way to load YouTube videos. The thumbnail used on YouTube is the preview image that will automatically be pulled. This is just an example below. Note: This does require iFrames and Videos to be enabled in Perfmatters.

By default, a low-resolution image is pulled from YouTube for the thumbnail. We have a filter you can use to change the quality of the thumbnail. The maxresdefault attribute will pull the highest quality if available. Make sure your YouTube thumbnails are at least x pixels.

Check out this great guide on how to size your YouTube thumbnails. See additional options for the filter. DOM monitoring watches for changes in the DOM and dynamically lazy loads newly added elements.

This improves compatibility with third-party plugins and themes that utilize features like infinite scrolling or gallery sliders. There may be times when you will want to exclude a specific image from being lazyloaded.

There are a couple of ways to do that. The easiest way is to use the UI in Perfmatters. Exclude an element by adding the source URL example. Format: one per line.

Many featured images, galleries, etc. This can sometimes make them hard to exclude globally. However, their parent container almost always has a pattern or unique string you can match.

This feature requires Advanced Options to be enabled. If you have access to add a CSS class to the specific image you are wanting to exclude, simply add the no-lazy class and it should be ignored when the document is being prepared for lazyloading. If the image you want to exclude is a bit harder to access and manipulate directly, we have a WordPress filter available which can be used to add any attributes or portions of attributes that are specific to the image in question.

This is simply a string match , so any portion of any attribute should work, it just needs to be an exact match for the image or images you are wanting to exclude.

Here is an example of an exclusion based on an image file name match. You can exclude an individual post, page, or custom post type from lazy loading.

If needed, you can extend the lazy loading threshold allowing images to load before they are visible in the viewport.

However, some might prefer to increase this as it can make scrolling a little smoother. Or in other words, there will be fewer pop-in of images as you scroll down the page. You can also use the following filter to change the viewport threshold for lazy loading.

Note: On sites with a lot of third-party JS for example, those running ad networks like Mediavine or AdThrive , we recommend setting the viewport threshold to at least px.

Some users like to have a fade in effect on images when scrolling down a page. This creates a smoother transition for images instead of just popping in immediately after they are lazy loaded. Perfmatters supports lazy loading inline background images without any additional configuration.

However, some page builders, themes, and plugins load background images in their CSS stylesheets. Perfmatters cannot change the contents of their CSS, but we can prevent certain containers from immediately loading their background image in the browser.

This enables you to lazy load CSS background images in things like GenerateBlocks, Elementor, Oxygen, Divi, Beaver Builder, etc.

In the Background Selectors box, input a specific ID or class found on the container or parent that contains the background image. Format: one per line, without the prefix. Note: Some solutions like GenerateBlocks let you switch the background image to inline , in which case, lazy loading would work automatically.

Some page builders and themes might not have unique classes on their divs containing the background images. In this case, if you have access to add an additional class to the container itself, you can add our perfmatters-lazy-css-bg class instead.

For example, in Elementor, you add it in the CSS Classes field on the div containing the background image. There may be times when an element coming from another plugin or theme already has an exclusion class or attribute applied that prevents our lazy load from picking it up by default.

If this happens, you may be able to force that element to lazy load with the following filter. This filter can be used the same as in the excluded attributes example, but when an element contains one of the included attributes, our lazy loader will skip checking that item for exclusions and continue attempting to lazy load that element.

This can cause conflicts and things not to work properly. This includes lazy loaders in other optimization plugins and solutions like Cloudflare Mirage. js from deferring. If a theme or page builder is using an! Using an! important class on everything is bad practice and should only be used as a last resort.

You can fix this with a little CSS. Here are a few examples.

From here, use JavaScript to check if the element is in the viewport with Intersection Observer! lazy-background element at that time, which loads the image:. Lazy loading is a great optimization that reduces both overall data usage and network contention during startup by deferring the loading of images to when they're actually needed.

This can improve startup time, and reduce processing on the main thread by reducing time needed for image decodes. However, lazy loading is a technique that can affect your website's Largest Contentful Paint LCP in a negative way if you're too eager with the technique.

One thing you will want to avoid is lazy loading images that are in the viewport during startup. When using JavaScript-based lazy loaders, you will want to avoid lazy loading in-viewport images because these solutions often use a data-src or data-srcset attribute as a placeholder for src and srcset attributes.

The problem here is that the loading of these images will be delayed because the browser preload scanner can't find them during startup. Even using browser-level lazy loading to lazy load an in-viewport image can backfire. Never lazy load images that are visible in the viewport during startup.

It's a pattern that will affect your site's LCP negatively, and therefore the user experience. If you need an image at startup, load it at startup as quickly as possible by not lazy loading it! You should use browser-level lazy loading whenever possible, but if you find yourself in a situation where that isn't an option—such as a significant group of users still reliant on older browsers—the following libraries can be used to lazy-load images:.

Except as otherwise noted, the content of this page is licensed under the Creative Commons Attribution 4. For details, see the Google Developers Site Policies. About Blog Articles Learn Explore Patterns Case studies.

Core Web Vitals Metrics Fast load times How to Optimize Interaction to Next Paint INP Progressive Web Apps Accessible to all Network reliability Safe and secure Easily discoverable Web Payments Media Devices Animations Identity WebAssembly Test automation React Angular Mini apps.

About Blog Articles Learn Explore Core Web Vitals Metrics Fast load times How to Optimize Interaction to Next Paint INP Progressive Web Apps Accessible to all Network reliability Safe and secure Easily discoverable Web Payments Media Devices Animations Identity WebAssembly Test automation React Angular Mini apps Patterns Case studies.

Core Web Vitals. Measure performance in the field. Optimize your resource delivery. Optimize your images. Lazy-load images and video. Optimize web fonts. Optimize your CSS. Optimize your third-party resources.

Optimize your JavaScript. Build a performance culture. Set performance budgets. Jeremy Wagner GitHub LinkedIn Homepage. Rachel Andrew X GitHub Mastodon Homepage. It is very useful when you play muted video in the background, for example.

See the action of improved lazy loading for image, audio, and video in a real demo. See also the article 8 tips to speed up image loading. On this page Optimizing lazy loading for images, videos, and audio: Best practices and strategies The solution: Streamlining lazy loading for enhanced user experience Demo: Visual example of improved lazy loading in action Performance enhancement with lazy loading: Does it really work?

Page url QR Code. While this looks like a good solution then it seems that we could improve that even further. What, if image, video, or audio can be fetched not only when they appear in the viewport, but also with a delay?

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loading can take any of these three values:. However, although at the time of writing most major browsers have good support for the loading attribute , not all browsers are on board yet.

The Intersection Observer API is a modern interface that you can leverage for lazy loading images and other content. Denys Mishunov has a great tutorial both on the Intersection Observer and on lazy loading images using it. The markup for each image would look like this:.

Notice how the path to the image is contained inside a data-src attribute, not a src attribute. The reason is that using src means the image would load right away, which is not what you want.

This gives each image placeholder the img element without the src attribute a vertical dimension:. In the JavaScript document, you then create a config object and register it with an intersectionObserver instance:.

Finally, you iterate over all of your images and add them to this iterationObserver instance:. Fortunately, a polyfill is available. A quick and easy alternative for implementing lazy loading of images is to let a JS library do most of the job for you. Lozad is a highly performant, light and configurable lazy loader in pure JavaScript with no dependencies.

You can use it to lazy load images, videos, iframes and more, and it uses the Intersection Observer API. Only, be mindful of browser support and eventually integrate this library with a polyfill for the Intersection Observer API. The first thing you see is a blurred, low-resolution copy of the image, while its high-res version is being lazy loaded:.

Yall is a feature-packed, lazy-loading script for images, videos, and iframes. More specifically, it uses the Intersection Observer API and smartly falls back on traditional event handler techniques where necessary. And there you have it — five ways of lazy loading images you can start to experiment with and test out in your projects.

Lazy loading is a web development technique used to improve the performance of web pages by deferring the loading of certain elements, such as images, until they are needed.

You can implement lazy loading for images in HTML using the loading attribute. The loading attribute is a standard HTML attribute that allows you to control when an image should be loaded. This tells the browser to load the image only when it is about to enter the viewport.

See the loading field of MDN's browser compatibility table for details of browser support. If the browser does not support lazy loading then the attribute will be ignored and images will load immediately, as normal. For most websites, adding this attribute to inline images will be a performance boost and save users loading images that they may not ever scroll to.

If you have large numbers of images and want to be sure that users of browsers without support for lazy loading benefit you will need to combine this with one of the methods explained next.

To learn more, check out Browser-level lazy loading for the web. If they are, their src and sometimes srcset attributes are populated with URLs to the desired image content. If you've written lazy loading code before, you may have accomplished your task by using event handlers such as scroll or resize.

While this approach is the most compatible across browsers, modern browsers offer a more performant and efficient way to do the work of checking element visibility via the Intersection Observer API. Intersection Observer is easier to use and read than code relying on various event handlers, because you only need to register an observer to watch elements rather than writing tedious element visibility detection code.

All that's left to do is to decide what to do when an element is visible. Now let's see how to use Intersection Observer in JavaScript to lazy-load images using this markup pattern:. If Intersection Observer is available, create a new observer that runs a callback when img.

lazy elements enter the viewport. Intersection Observer is available in all modern browsers. Browser-level lazy loading does not apply to CSS background images, so you need to consider other methods if you have background images to lazy-load.

When the document and CSS object models and render tree are built, the browser examines how CSS is applied to a document before requesting external resources. If the browser has determined a CSS rule involving an external resource doesn't apply to the document as it's currently constructed, the browser doesn't request it.

This speculative behavior can be used to defer the loading of images in CSS by using JavaScript to determine when an element is within the viewport, and subsequently applying a class to that element that applies styling invoking a background image.

This causes the image to be downloaded at the time of need instead of at initial load. For example, let's take an element that contains a large hero background image:.

The div. lazy-background element would normally contain the hero background image invoked by some CSS. In this lazy loading example, however, you can isolate the div. lazy-background element's background-image property via a visible class added to the element when it's in the viewport:.

From here, use JavaScript to check if the element is in the viewport with Intersection Observer! lazy-background element at that time, which loads the image:.

Lazy loading is a great optimization that reduces both overall data usage and network contention during startup by deferring the loading of images to when they're actually needed.

This can improve startup time, and reduce processing on the main thread by reducing time needed for image decodes. However, lazy loading is a technique that can affect your website's Largest Contentful Paint LCP in a negative way if you're too eager with the technique.

One thing you will want to avoid is lazy loading images that are in the viewport during startup. When using JavaScript-based lazy loaders, you will want to avoid lazy loading in-viewport images because these solutions often use a data-src or data-srcset attribute as a placeholder for src and srcset attributes.

Videos have become an essential part of web content, helping businesses showcase their products or services, promote their brand, and create engaging experiences for visitors.

The catch? The crux of the problem is that low-quality videos load fast, but are a massive turn-off for audiences. Large, high-resolution videos are far more attractive but hog bandwidth and device resources, ultimately slowing down any user interface.

Worse, this has a cumulative effect — it leads to perceived lag and sluggish UI, which leads to a bad first impression of your site, which leads to high bounce rates, i. users growing impatient, and leaving your website for greener pastures. Fortunately, there is a reliable way to balance video quality and snappy UI — lazy loading.

This involves loading videos only when they are needed, such as when a user clicks on a thumbnail, or scrolls to a section of the page where the video is located. Lazy loading is a technique to defer the loading of those non-blocking, non-critical resources until they are actually needed by the user.

This shortens the length of the critical rendering path , ultimately translating to faster websites.

By deferring the loading of video data until it is actually needed, lazy loading reduces the initial load time of the webpage, and also the amount of effective data that needs to be downloaded. There are three ways of doing this. The preload attribute set to none tells the browser to not load video data upon page load, and that playing the video is entirely up to the user the controls attribute enables the latter.

Plus, Native lazy loading doesn't require any extra JavaScript so no dependency to manage, no bugs or compatibility issues to sort out , the content will still load if a script fails to load or is blocked, and the browser is going to make better, faster decisions about which videos to load and when than any JS plug-in ever could.

The Intersection Observer API is used to detect the visibility of an element, or the relative visibility of two elements in relation to each other, and take action. This gives us the ability to implement the following strategy :. By making the tradeoff of having more JavaScript, we gain the ability to be more fine-grained with our implementation of lazy loading.

This approach is entirely in JavaScript, meaning our two drawbacks with the native approach are now gone:. LazyLoad is a free and open-source, lightweight 2. Written in plain "vanilla" JavaScript, it leverages Intersection Observer, supports responsive images, and enables native lazy loading.

Another free and open-source, highly performant, lightweight ~1 KB gzipped and minified , and configurable lazy loader, written only in pure JS with no additional dependencies. It enables lazy loading for images, iframes, videos, audio, and more, using IntersectionObserver API only.

It even supports hassle-free LQIP Low-quality image placeholders implementation. This is an SEO-friendly lazy loader that uses Intersection Observer where available, falling back to event handlers otherwise.

js can also monitor the DOM for changes using Mutation Observer to lazy load elements that have been appended dynamically to the DOM after the initial load, which makes it ideal for SPA use cases. Now, using Chrome as our example, hit F12 to bring up Chrome Dev Tools, navigate to the Network tab, and then Media to check the loaded media assets.

for a bit. Why re-invent the wheel? There are a number of JavaScript libraries which combine the mentioned techniques. Wouldn't it be awesome if there was a native lazy loading API? Quick heads-up: there's a video below the snippet. This video starts lazy loading when the video is visible.

We adapted this snippet from Google's Developers Blog. The following snippet could be used to achieve lazy loading through the LazyLoad library. The following snippet uses the Intersection Observer API to achieve lazy loading for iframes.

We'll use YouTube as our sample case. Another quick heads-up: there's an iframe below the snippet. This iframe starts lazy loading when the iframe is visible. We adapted the JavaScript from Chris' blog to load the iframe on-demand.

This snippet puts the iframe in a container, to make the iframe responsive to a aspect ratio. With JavaScript video players, the same principles as HTML videos apply: load the video when the video player becomes visible.

Additionally, you want to asynchronously load their JavaScript libraries. This codepen. io snippet uses the Intersection Observer API, the JavaScript API of the video player and async JavaScript to achieve lazy loading with the video player below. Developers can use the Intersection Observer API to lazy load videos in order to optimize the critical rendering path.

You should leverage lazy loading when it makes sense for your use-case. If you're building a video streaming website, you probably want to preload some videos. If you're doing livestreaming, it might not even make sense to preload data, because loaded data will be outdated when you hit play.

Stay up to date! src sets the video source. preload preloads data. If your src is configured, set preload to none to avoid preloading.

autoplay starts playing the video automatically, which means the video download starts. Heartbeat Control by WP Rocket : Heartbeat Control by WP Rocket: The best plugin to control the WordPress Heartbeat API and reduce CPU usage.

RocketCDN: The best CDN plugin for WordPress to propel your content at the speed of light — no matter where your users are located in the world. Increase Max upload file size is the best plugin to increase the upload file size limit to any value with one click.

I'm very happy with the plugin! Everything works as described. Produto muito bom, meu site ficou mais rapido ao usa-lo. Contributors WP Rocket WP Media. Interested in development? Changelog 2. com during LazyLoad 2. rocket-lazyload is contained in the new node s added to the DOM 2.

See FAQ for more info. This option can improve your loading time a lot, especially if you have multiple videos on the same page 1. Meta Version: 2.

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