Comment Re:Did new features always take this long? (Score 1) 48
As the mid 90's approached, 16bpp and even 24bpp were starting to become more common. This was when the 8bpp limit of GIFs was noticeable. The most obvious use for these higher bit-depths were digital photos, which because photos by nature are very irregular are hard to compress using a lossless algorithm. So JPEG - a lossy image-compression algorithm that works in 24bpp was chosen. It was more than a year after Mozilla introduced inline images that inline JPEGs were supported by Netscape (Mozilla only added support a few months later).
At first, JPEG didn't take off because web-developers were reluctant to use an image-format supported only by a few browsers, and back then, 8bpp graphics-hardware was still common. But then in early 1995, it was announced that UNISYS held a patent related to GIF that restricted it's usage. Because of that, many websites started using JPEG (although many websites still continued to use GIF). However, Netscape still had a trick up their sleeve. They noticed that the specification for GIFs allowed them to contain animation, and they implemented support for animated GIFs in their browser in late 1995 (this was even after they implemented support for Java which also would have allowed animation).
But JPEG had a restriction - it couldn't compress an image losslessly. While JPEG was great for photos, it would itroduce noticable artefacts on drawings, diagrams, etc.). To get round this restriction, and the fact that GIF was limited to 256 colours and had a patent, a new format was developed - PNG. This was a lossy 32bpp format (8R8G8B and 8A) that included alpha-channel support (GIFs did support transparency, but it was 1-bit (either fully transparent or fully opaque)), and used a much better lossless compression algorithm than GIF. While web-browsers supported inline PNGs as early as 1995, because the format hadn't matured yet, it took several years for it to take off. Holding up progress were several PNG-related bugs in Internet Explorer 6 (used by >90% of computers in the early-mid 00's) that didn't render certain types of PNGs properly (eg. ones with alpha channels). Add to that the fact that the UNISYS patent expired in 2004, it meant that for line-drawings, many people stil preferred GIF over PNG simply because MSIE6 often botched PNG-rendering. These days, PNG is pretty common when using images more suited to lossless compression.
PNG images are static and don't support animation. Two attempts were made in the early 2000s to support PNG-animation - APNG and MNG. Both didn't take off, so for animated images, we're still - in 2026, when nearly everyone has a 24bpp display - mostly using animated GIFs and their 256-colour limitations to show animated images on the web.
After many years of new image-formats that either died or did not gain traction, JPEG-XL appeared. It could finally replace both lossy JPEGs and lossless PNGs and animated GIFs, but was held back by browser developers. Google wanted to push either WebP or HEIC, and deliberately did not support JPEG-XL, but the tide has finally been turning. With both Chrome and Firefox (and presumably Edge which uses Chromium following soon) supporting JPEG-XL out the box, websites could finally shift over to JPEG-XL. The ability to losslessly transcode JPEGs into JPEG-XLs helps the transition, and if the server detects an old version of a browser, it can translate a JPEG-XL back into a JPEG in real time. So we might now finally be seeing more annd more websites starting to use JPEG-XL.
However, the fact that 25 years after the first attempt was made to introduce animated 24-bpp images, GIFs are still used, might give a warning that the transition may take some time. Hopefully, JPEG-XL support from all major browsers and image-viewers and an easy way of shrinking JPEGs by converting them losslessly to JPEG-XLs will make the transition easier.