Here, we’re going to take a look at the difference between standard and progressive JPEGs. What’s more, we’re also going to show that you can actively use progressive images to increase the loading time of your website, and enhance user experience for your website visitors.
To begin with, let’s start by understanding what a JPEG is. JPEG stands for “Joint Photographic Experts Group”, the team that were responsible for creating the image format in 1992. These images can use the file extension name .jpg, or .jpeg. Usually, JPEG images work best with realistic images and photographs that have a smooth combination of color and tone. Because the compression of such images is quite efficient, it’s web usage is very popular.
Defining the Progressive JPEG
A progressive JPEG is a type of image that can be created using algorithms for compression which load the picture through waves of succession
the image in successive waves until the complete image is downloaded. This technique gives the perception that the images are loading faster, because the user will be able to see the complete image straight away, rather than the traditional format that JPEGs use to load, which involves working one line at a time from bottom to top.
Progressive JPEGs were very popular in the 1990s, when the internet relied on slower dial-up connections, before the GIF format began to gain popularity. However, more recently, as the increase in mobile devices rises with slower internet connections, the time that’s required for images to load has slowed down significantly.
With traditional JPEGs leaving a lot of white space on the screen until the image has finished loading, these web pages can appear to load very poorly. However, with progressive images, the page seems like it’s loading more quickly, as there’s no whitespace and the image complete the rendering process once the page seems to finish loading.
Progressive images are ideal for working with modern browsers such as the latest Internet Explorer, Chrome, and Firefox. The only browsers that seem to have serious problems with this format are those that include Internet Explorer 8 and below. However, even when a browser doesn’t support these images, they will still display, only after the complete image has loaded.
Creating Progressive JPEGs
By default, most image-editing tools will save your image in its baseline format. Until 2015, a service known as “Smushit” was used to optimize images for most people, which converted them into progressive files in the process. Today, there are still many image editing tools that can be used to save a picture as a progressive file, including Fireworks, ImageMagick, Photoshop, and more. However, this will involve manually loading your image into the editor and then saving it again.
Photoshop is the preferred image editor for most people, but Adobe has somewhat complicated matters in their latest editions of Photoshop by removing the option to save your content as a progressive image. However, you can still find the option by going into File, Export, and “Save for Web (legacy). When you’re saving, all you have to do then is tick the “progressive” option.
Alternatively, an almost complete replacement for the previous Smushit service is something called Kraken.io. This service can be used through the web, or through one of their existing integrations, including on WordPress.
The interface for this system is very easy to use, however, with the free plan, you can only upload a single file at a time, which can sometimes be up to 1MB in size. You will also be able to choose between high compression or low compression.
The WordPress plugin for this solution only works alongside the free plan for the service for a limited amount of time, or up to 50MB in total. However, to make the most of the system, you can always pay for one of the more premium plans. There are some extremely cheap options for smaller businesses on a budget, and if you’re looking for a solution that will help you to make sure that your images don’t slow down your website and stop you from earning money, then this could be what you’re searching for.
Remember, when you’re using the WordPress plugin, you’ll benefit from a product that automatically optimizes and converts your image files as soon as you upload then. Also, you’ll be able to optimize your existing files within your media library.