Today, we have many image codecs to work with. Images come in all shapes and sizes but also formats. However, many do not realize how important it is to have more than one image codec to choose from. Today, JPEG is among the most popular image codecs used worldwide. JPEG / JPG is an image file format and an abbreviation for Joint Photographic Expert Group. Invented in 1992, it is one of the oldest and most common image file formats on the Web. It is widely used on the Internet and beyond and offers excellent image compression. For over two decades, JPG has been the default choice - but now, various alternatives and rivals are appearing that can compete with JPG as the default image codec. Interestingly, the latest next-generation image codec receiving much positive attention is known as AVIF. AVIF (AV1 Still Image File Format) is an image file format derived from the AV1 video format developed by the Alliance for Open Media and used primarily in browsers such as Google Chrome and Mozilla Firefox. It is based on the AV1 video codec and is widely used by media giants such as Netflix. AVIF provides crisp, impressively detailed images while reducing the payload in the background. Although JPEG was once the default choice for all types of images, it has several limitations that can minimize its usefulness. For example, JPG lacks alpha transparency support - a big problem for a large number of users. In addition, the 8-bit limit means that it may have difficulty creating HDR-friendly images with high dynamic range while at the same time limiting the quality of compression.
If you focus on the discussion about which image codec is the best, there will be one opinion or another. However, there is no denying that JPEG suffers in terms of compression quality today. Indeed, even the more modern JPEG 2000 can offer better overall compression. However, if you want better results, many codecs offer a more satisfactory, crisper result. For example, lossless compression and lossy photo compression are much more efficient when using AVIF. AVIF tends to provide some of the best results we can achieve with lossy, non-photographic images. For those who are dealing with an image with low fidelity, AVIF is currently the first choice. Crucially, AVIF can also offer a substantial reduction of an image. File reduction is essential for faster loading times. As AVIF can perform reductions of 40% to 90%, one can see a huge difference. It comes to JPEG imagery and then around 20% savings when compared to WebP. It’s easy to see why AVIF wins the prize regarding image size to image quality. There are also limitations when comparing AVIF with JPEG. For example, JPEG is limited to using an 8-bit color precision system, which means that in the era of HDR, JPEG cannot achieve the same color quality of color. HDR today expects higher, at least 10-bit precision. AVIF can guarantee an even 12-bit precision and can also process HDR / Wide Gamut images. It also has a maximum number of five channels higher than the four channels allowed by JPEG. Another critical aspect of the JPEG-vs-AVIF discussion is about artifacts. Today, many image types use a tile boundary to try to split an image to make sure it fits into the maximum size provided. Dimensions per tile can typically leave traces that blur parts of the image or show clear connection lines. Since AVIFs can capture an image/video image the size of an 8K video, its use in modern photos is apparent.
Another crucial aspect, is speed. JPEG was written before the invention of multicore CPU chips. So it is designed to work with a sequential process where the number of cores does not matter; it is the clock speed. Today, CPU development is primarily focused on multiple cores, so JPEG cannot benefit from multicore processing. AVIF can do what makes it a more suitable form of image compression for the future. Tit should be noted that the AVIF image format currently has slow encoding times. This should change over time; AVIF is still relatively new, so hardware support is still arriving. Expect an improvement in encoding times. Furthermore, an AVIF image does not support progressive rendering, so files must be downloaded entirely before they can be displayed. Often, this has little impact on the real-world user experience, as AVIF files are much smaller than the corresponding JPEG or PNG files, and therefore can be downloaded and displayed much faster. For larger file sizes, the impact can be significant, and you should consider using a format that supports progressive rendering.
As you may know, JPEG is an image format. This means that it is typically designed to show still images. AVIF is based on an actual video codec and provides animation capacity. This means that it can support animations and movements in a way that JPEG can not.
Main differences for Nerds
There are some crucial differences when it comes to looking at the differences in the JPEG vs. AVIF debate. For example, you will find that AVIF supports features such as:
- Any color space including wide color gamut, ISO/IEC-CICP, and ICC
- NCLX support: sRGB, linear sRGB, linear Rec2020, etc.
- 4: 2: 0, 4: 2: 2, 4: 4: 4
- 8, 10, 12-bit color depth
- High dynamic range
- Lossless compression and lossy compression
- Excellent lossy compression compared to JPG
- No progressive ren
- Monochrome sup
- Tiling support
- Film grain support
- Supports animations that JPEG cannot do
- Provides the ability to use alpha transparency
- Can use overlays, another feature that JPEG cannot handle
Comparing these critical features with JPEG, it is easy to see why there is such a movement towards a long-term shift to AVIF. It provides enough detail and additional features to ensure that someone can deal with a better, more detailed form of the image without increasing the image size at all. This is necessary to ensure that we can obtain crystal clear images that use all modern systems while avoiding unnecessarily large image sizes. The ability to use overlays is a significant advantage of AVIF over JPEG. You can use functions such as additional layers, color channels, and masking without any problems. JPEG, on the other hand, can be saved with an intact layer.
Main differences for Marketeers
Simply put, AVIF has a better chance of being supported in the long term. It also has a higher degree of compression efficiency and can work with a broader range of functions as described above. Typically, the main differences between AVIF and JPEG could then be broken down as follows, with AVIF providing:
- higher image quality.
- lower image size.
- slower processing time, expected to improve over the years.
- less, but still relatively high browser support.
At the moment, many still see the use of JPEG as an ideal way to move forward in the short term. As more and more images fall within the overlay standards mentioned above, it should be assumed that JPEG will show its age within the next 3-5 years. The AVIF format will be used more frequently, as it offers the speed of loading, if not processing, and the quality of the image. Also, in terms of the number of image options, and this is a no-brainer: AVIF has more or less everything that JPEG lacks, apart from the broad uptake on the market. In time that will change.
Most image codecs will be a significant improvement over what we have used in JPEG so far. Although the improved JPEG 2000 also offers substantial improvements over its predecessor, it still cannot compete with AVIF in many ways. AVIF has become the ideal choice for those who need to manage encoding in a low bandwidth setting. So while JPEG might have the advantage of progressive rendering – it would be fair to say that AVIF has all the features that JPEG lacks and frankly needs. The AVIF file is a superior image file format over JPEG / JPG. However, hardware and software support is still evolving at the time of writing. Fallbacks in the code can allow you to use AVIF alongside image formats such as JPEG, WebP, PNG, etc. There is still much to consider regarding both image types. At the moment, AVIF has the best chance of still being available in a decade compared to JPEG. Although JPEG may be the old pioneer of image codecs, it may finally replace it.