Using WebP Format in Sitecore .


WebP is a promising format that allows good optimisation comparing to JPEG and PNG. According to tests, it provides lossless images that are 26% smaller compared to PNGs and lossy images that are 25-34% smaller than comparable JPEG images at equivalent SSIM quality index.

This format becomes more and more popular over the web nowadays. Google promotes WebP format, it released WebP as open source to allow anyone works with it and suggest improvements. But, is it supported by major browsers? Going to CanIUse gives an answer that not:


(support details are on 2018/01/21, it could be changed over time)

It is supported by Chrome, Opera, Chrome for Android. Safari and Firefox are experimenting(not supported yet) with supporting WebP images. IE and Edge doesn’t support it.

But how it can be used now, when not all browsers support it? Each browser (web client) provides Accept header when getting resources from server. If this header contains image/webp, web server know that it can returns WebP format. As example Akamai CDN use this behaviour. It can return optimised WebP images for web clients who support it and JPEG and PNG for those who doesn’t support.

Let’s consider how it could be used in Sitecore. It has no sense to add support of WebP format to media library for now, we can’t return this file format to all web clients. But it makes sense to return WebP format to web clients that can use it. Saving about 25% of time on loading images can make big difference for user experience, especially on mobile. I decided don’t write new image optimiser from the scratch and add support of WebP to well known tool for images optimisation for the Sitecore: Dianoga.

To make it works, we should get understanding how Sitecore Media Library and Sitecore Media Library cache work. Sitecore media library creates files on disk after each request, or uses previously created files. By default these files are located under \Website\App_Data\MediaCache\website\{some folders}. There are few files in each folder. First type of files is cache for image. It is image itself, Sitecore don’t need to preprocess width, height and other parameters for each media request. It does processing only once. Second type of files is .ini file, it is metadata for cached object. Metadata contains next values:

  • Key - e.g. ?as=False&bc=0&h=0&iar=False&mh=0&mw=0&sc=0&thn=False&w=0. Key contains all media query parameters.
  • Extension - extension of file.
  • Headers - cached headers that should be returned to web client
  • DataFile - file name of object that should be returned to web client.

We need to extend forming of key, to add one more parameter that will indicate support of WebP format. It will require extending of MediaRequestHandler:

public class MediaRequestHandler : Sitecore.Resources.Media.MediaRequestHandler


         protected override bool DoProcessRequest(HttpContext context, MediaRequest request, Media media)


                  if (context?.Request.AcceptTypes != null && (context.Request.AcceptTypes).Contains("image/webp"))


                        request.Options.CustomOptions["extension"] = "webp";


                return base.DoProcessRequest(context, request, media);


          private static bool AcceptWebP(HttpContext context)


               return context?.Request.AcceptTypes != null && (context.Request.AcceptTypes).Contains("image/webp");



Our key will contain one more additional parameter: extension. E.g.: ?


Let’s add handler that will process WebP compatible requests based on CommandLineToolOptimizer:

public class WebPOptimizer : CommandLineToolOptimizer


        public override void Process(OptimizerArgs args)


              //If WebP optimization was executed then abort running other optimizers

               //because they don't accept webp input file format

                if (args.AcceptWebP)






       protected override string CreateToolArguments(string tempFilePath, string tempOutputPath)


             return $"\"{tempFilePath}\" -o \"{tempOutputPath}\" ";



It is very easy, it runs cwebp.exe tool that converts JPEG or PNG to WebP. It doesn’t utilise all available command line options and could be tuned depending on requirements. All others code changes are more about Dianoga configuration and unit tests, I will not stop on them in this article. If you want more details, you can review all changes in GitHub repository.

How to enable Dianoga WebP support for your project:

  1. Clone GitHub repository and build project
  2. Enable Dianoga.WebP.config.disabled config
  3. Open web.config and change line <add verb="*" path="sitecore_media.ashx" type="Sitecore.Resources.Media.MediaRequestHandler, Sitecore.Kernel" name="Sitecore.MediaRequestHandler" /> to <add verb="*" path="sitecore_media.ashx" type="Dianoga.MediaRequestHandler, Dianoga" name="Sitecore.MediaRequestHandler" />
  4. If you have custom MediaRequestHandler (e.g. Habitat is used) then skip step 3 and override DoProcessRequest method with detection of support of WebP format. See MediaRequestHandler code listening above.

P.S. this is an experimental feature, use it at your own risk. :-)

Whatever your business, be it a regional or global brand, the content you produce plays a vital role in your success. You know that… hence you’re reading this.

A well formulated and executed content strategy not only drives more traffic, at the core, it defines what your business is and helps build a strong connection between you and your audiences.

So let's quickly look at why developing a coherent content strategy is important and how setting clear goals and understanding your audience will elevate your online performance. 

What is a Content Strategy?

It's basic right? Content is at the core of how you define the way your business presents itself and an effective strategy should look to ensure that tone of voice, messaging and the core values are surfaced across all channels, from service or product pages on your website, to blog posts, through social media updates blah blah blah.

But let's keep it simple - your content strategy should be a clear roadmap that connects your marketing activities to your business goals. Align to your customer’s wants and needs and engage them at every interaction point and boom, you're in business. 

Who are my Audience?

You likely start all your projects with this chalked on the wall because your business knows “exactly” who its customers are right? Sounds obvious but we often find its not been done forensically enough (not based on data), is too old (more than 12 months ago - forget it) or its a spin off from some brand work that was legitimately aspirational but doesn’t face the reality of who you your business is actually engaging today.

So start (or circle back) with audience research, building out those personas to understand their ambitions, their lifestyle, their pain points or concerns, and crucially their wants and needs - in your context. 

Do I need to tailor content?

As part of your research find out where your audiences spend their time online and how they interact with content: Some may spend time thoroughly researching a product or service, whereas other audiences may want their content to be quick, snappy or easily digestible in the form of a video, infographic or short blog posts.


Ultimately, the key is to produce a strategy that creates the type of content your customers want to see:

  • What are the problems that your product or service will help them solve?

  • Who are they most influenced by?

  • What voices influence their behaviour?

  • What type of content do they consume?

  • Where do they consume content and engage with brands?

Different Content, Different Objectives

 All content is not born equal: When producing your strategy, it is important that the objectives for each individual piece are defined, that these fulfil your marketing objectives and tie to the overarching goals for your business.

There are various content frameworks that exist to aid content development in this way, but one that is popular and effective is Google’s hero, hub and hygiene method: It provides a framework on developing content to achieve different goals and gives guidance on the effort needed to create each type of content.

Hero Content

Hero content is essentially campaign content, it is big splash ideas designed to appeal to a large audience with the aim of telling your brand’s story at scale. 

Ways of measuring hero include the amount of PR mentions or links from authoritative domains plus social interactions and mentions of your brand across all channels. 

Considering the scale of hero campaigns, this content is not regularly produced and is reserved for peak promotional times where it’s important for a business to stand out from their competitors.

Hub Content

Hub content is the stuff that keeps your audience engaged, it expands on the themes of product or service level content, educates users and helps create a connection between themselves and your brand.

Hygiene Content

Hygiene content is the bread and butter of any website, it is the BAU content for products and services, it is SEO focused and targets important keywords at a product, service or guide level.

How do I manage all this?

Content development is only one part of the ongoing work needed when working with an effective content strategy. We call it “feeding the beast” because it really is the fuel in your brand vehicle and once you start you really can’t stop (if it’s delivering results) but that’s where performance measurement comes in.

Your greatest gift in managing the outputs from your hero/hub/hygiene style efforts is to understand If your content is working. To truly deliver results your business must first understand the objectives and goals of each piece of content to effectively measure its success. That as a guiding light from day 1 will let you slow down, speed up, stop or start new content briefs and projects.

Remember - content strategies are not set in stone. They are living breathing things and should adapt and pivot as insights become available and your brand naturally evolves.

If ever you want to chat content and explore new initiatives we’re always here to help.

want to speak to one of our experts?

Anton Tishchenko Thumbnail
Anton Tishchenko
Head of Digital Engineering
Anton has worked as a developer since 2007, he is a highly experienced Sitecore developer who previously worked as a Technical Team Lead at Sitecore. Anton's expertise in the Sitecore platform is formidable; he's definitely one of the world's finest Sitecore ninjas and in 2019 he was recognised as the only Sitecore MVP in the Ukraine when he achieved his Technology MVP Status.
Anton Tishchenko Thumbnail

Anton Tishchenko

23 Jan 2018 - 8 minute read
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