The H.A.C.K.E.R. Project

There are multiple types of image files that are used throughout the Internet, such as .jpeg, .png, and .gif. Each file type provides its own benefits. For example, .gif files can contain multiple frames which allow them to appear as animated images, while .jpeg images use compression to make the file smaller. One relatively new type of image file is the .webp file, originally created in 2010 by “On2 Technologies — a company [later] acquired by Google” (Google).

What is a WebP File?

WebP is “an open-source image file format that was developed by Google” (IU CeLT Authors). Files that are in WebP format will end in .webp. Google originally “created the WebP file format to make online images less bulky” and to provide “superior lossless and lossy compression for images on the web” (Adobe; Google). Additionally, it provides similar capabilities to .gif files, allowing for short animations to be store as .webp files instead. When this file format was first released, it “was expected to be widely adopted after development but, as of right now, usage is fairly limited to Google results” (IU CeLT Authors). However, it appears to be slowly gaining traction.

File Compression

One of the main concerns with uploading and downloading media to the Internet is the file size. In many cases, a form of compression is used. This is because smaller files, including images, “ease the strain on user broadband connections and make websites faster to navigate, improving page experience” (Adobe). Compression, as the name implies, shrinks a file down by reducing the amount of storage space the file takes. In terms of pictures, this may be done by decreasing the resolution of the image (lossy compression, since some quality is lost) or by encoding duplicate data to take up less space (lossless compression, since the duplicate data is able to be decoded when viewing the file). WebP files are able to make use of both lossy and lossless compression in order to allow “websites to display high-quality images — but with much smaller file sizes than traditional formats” (Adobe).

WebP lossless images are 26% smaller in size compared to PNGs. WebP lossy images are 25-34% smaller than comparable JPEG images at equivalent SSIM quality index.

Lossless WebP supports transparency (also known as alpha channel) at a cost of just 22% additional bytes. For cases when lossy RGB compression is acceptable, lossy WebP also supports transparency, typically providing 3× smaller file sizes compared to PNG.

Lossy, lossless and transparency are all supported in animated WebP images, which can provide reduced sizes compared to GIF and APNG.

Google

Additionally, “an animated WebP can be significantly smaller than a GIF, requiring fewer bytes” (Adobe). Keep in mind, however, that “a small amount of compression can reduce the quality of an image”, so if you utilize this file, some of the image quality may be lost depending on how the file is compressed (Adobe).

More on WebP Files

In terms of compatibility, WebP files are “natively supported in Google Chrome, Safari, Firefox, Edge, the Opera browser, and by many other tools and software libraries”, which makes them quite universal (Google). WebP was “designed mainly with the internet in mind, so it might not be helpful if you use images offline” or without transferring them across the Internet (Adobe).

Since the file type is still new, some software- such as “photo/graphic editing programs” may not recognize it as a valid image type, and “[w]hen working with a WebP image, you will likely need to begin by converting the image to another format” (IU CeLT Authors). The Authors from IU CeLT recommend Microsoft Paint as a free, easy to use option for converting WebP files to other image types. All you need to do is “open the WebP file in Paint and then use the ‘Save as…’ function to save the image in a new format” (IU CeLT Authors).

Resources & Further Reading

Adobe. “WebP Files Explained | Google’s Web Image Format | Adobe.” Www.adobe.com, www.adobe.com/creativecloud/file-types/image/raster/webp-file.html.

Google. “A New Image Format for the Web  |  WebP  |  Google Developers.” Google Developers, 2019, developers.google.com/speed/webp.

IU CeLT Authors. “What Is the ‘.Webp’ Format Image?: Multimedia Tips: CELT Resources: Center for Language Technology: Indiana University.” Center for Language Technology, 2021, celt.indiana.edu/resources/multimedia/webp.html.