WebP vs AVIF: Modern Image Formats

The importance of image formats for website acceleration is significant as they can help reduce file size, maintain image quality, and support transparency and animation effects. These factors are crucial for improving website performance, optimizing user experience, and saving server bandwidth. Understanding the characteristics and development history of different image formats can aid website developers in making wise decisions in optimizing website loading speed and user experience.

Common Image File Types

1. WebP: Excellent choice for both images and animated images. WebP offers much better compression than PNG or JPEG with support for higher color depths, animated frames, transparency, etc. AVIF offers slightly better compression but is not quite as well-supported in browsers and does not support progressive rendering.
   Support: Chrome, Edge, Firefox, Opera, Safari
2. AVIF: Good choice for both images and animated images due to high performance and royalty-free image format. It offers much better compression than PNG or JPEG with support for higher color depths, animated frames, transparency, etc. Note that when using AVIF, you should include fallbacks to formats with better browser support (i.e. using the <picture> element).
   Support: Chrome, Edge, Firefox (still images only: animated images not implemented), Opera, Safari.
3. JPEG: Good choice for lossy compression of still images (currently the most popular). Prefer PNG when more precise reproduction of the image is required, or WebP/AVIF if both better reproduction and higher compression are required.
   Support: Chrome, Edge, Firefox, IE, Opera, Safari.
4. PNG: PNG is preferred over JPEG for more precise reproduction of source images, or when transparency is needed. WebP/AVIF provides even better compression and reproduction, but browser support is more limited.
   Support: Chrome, Edge, Firefox, IE, Opera, Safari.
5. GIF: Good choice for simple images and animations. Prefer PNG for lossless and indexed still images, and consider WebP, AVIF, or APNG for animation sequences.
   Support: Chrome, Edge, Firefox, IE, Opera, Safari.

Why use WebP or AVIF?

Both WebP and AVIF are modern image formats that play a crucial role in website acceleration. Compared to traditional JPEG and PNG formats, WebP and AVIF offer higher compression rates and better image quality, ultimately reducing file size, improving website loading speed, and providing a better browsing experience for users.

1. File Size: Both WebP and AVIF formats can significantly reduce file size while maintaining image quality. According to Google's data, WebP images can reduce file size by 25%-34% compared to JPEG images. AVIF format, being more advanced than WebP, offers even better compression, further reducing file size.
2. Image Quality: Both WebP and AVIF formats can maintain high image quality during compression. In particular, the AVIF format uses more advanced encoding technology, providing clearer and more delicate image effects at the same file size.
3. Loading Speed: Due to the reduced file size, both WebP and AVIF formats can significantly improve a website's loading speed. Loading speed is crucial for user experience, as many users may abandon a site if the waiting time is too long. Fast-loading websites can increase user satisfaction, reduce bounce rates, and ultimately improve conversion rates.
4. SEO Optimization: Website loading speed is also an essential factor in search engine optimization (SEO). Fast-loading websites may achieve higher rankings in search engine results, attracting more traffic.
5. Bandwidth Savings: For website owners, using both WebP and AVIF formats can save bandwidth resources. Reducing file size means servers need to transfer less data, lowering operational costs.

AVIF vs WebP

AVIF and WebP are both modern image formats that offer higher compression rates and better image quality compared to traditional JPEG and PNG formats. However, there are some differences and advantages between them:

Advantages of AVIF

1. Higher compression efficiency: AVIF uses image encoding technology based on the AV1 video codec, which allows it to provide better image quality at smaller file sizes compared to WebP. This means that AVIF images may have smaller file sizes than WebP images at equivalent quality.
2. Better color representation: AVIF supports 10-bit and 12-bit color depth, while WebP only supports 8-bit color depth. This allows AVIF to provide richer color representation and smoother color transitions.
3. HDR support: AVIF supports High Dynamic Range (HDR) images, offering higher contrast and a wider color range. WebP does not support HDR.

Advantages of WebP

1. Wider browser compatibility: WebP format is more widely supported in mainstream browsers, including Chrome, Firefox, Edge, and Opera. Although the AVIF format is gradually gaining support, it is not yet fully widespread.
2. Mature ecosystem: As WebP has been around for a longer time, many image processing tools, content management systems (CMS), and development libraries already support the WebP format. AVIF, as a relatively new format, is still developing its ecosystem.

In summary, AVIF has advantages in compression efficiency, color representation, and HDR support, while WebP excels in browser compatibility and ecosystem maturity. When choosing an image format, you can consider which format to use based on specific needs and compatibility. Additionally, you can use multiple formats and combine the features of modern browsers to provide the best image experience for different browsers.

Image Format Conversion

Converting images to WebP or AVIF formats can be achieved using various tools and methods:

1. Command-line tools: For WebP, you can use Google's "cwebp" tool, while for AVIF, you can use "libavif" or "avifenc". These tools allow you to convert images in batch mode, adjust quality settings, and resize images.
2. Image editing software: Programs like Adobe Photoshop, GIMP, and ImageMagick support WebP and AVIF formats, allowing you to convert and edit images using familiar interfaces.
3. Online converters: Websites like Squoosh. app, Convertio, and CloudConvert offer user-friendly interfaces for converting images to WebP and AVIF formats without the need to install any software.
4. Plugins and libraries: For popular content management systems (CMS) like WordPress, plugins such as WebP Express and EWWW Image Optimizer can automatically convert and serve images in WebP or AVIF formats. Additionally, various JavaScript libraries and frameworks can help with image format conversion in web applications.
5. Content Delivery Networks (CDNs): Tencent EdgeOne is a next-generation CDN that offers advanced image processing capabilities, including resizing and converting images. The entire process - from processing, and caching, to responding - is handled on EdgeOne servers. This means your origin only needs to maintain the original images, significantly reducing your image management costs. Furthermore, EdgeOne can compress images to enhance page load speed without compromising visual quality. It also supports the conversion of images between various formats, such as WebP to JPG, WebP to GIF, AVIF to JPG, and AVIF to WebP, among others. We have now launched a free trial for the first month. Click here or contact us for more information.

By understanding and utilizing WebP and AVIF formats in website performance optimization, you can significantly improve image acceleration, enhance user experience, and boost organic traffic. Converting images to these modern formats is a crucial step in achieving these benefits.