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State of the JPEG2000 Standard?
ehb asks: "With all the (r)evolutions going on in networking (IPv6), video (MPEG4/H.264) and audio (MPEG4 AAC), I was wondering what happened to that big image compression promise of some years ago: JPEG2000. According to the official JPEG2000 page, although the entire standard not is completed, the important parts are, which would allow JPEG2000 to function as a still-image replacement for the old JPEG! I have seen lists of software programs that implement (parts?) of the JPEG2000 specification, but missed the important ones (web browsers, etc). There even exists an Open source implementation of the codec, so what is holding everything back? The benefits over normal JPEGs are huge, so can someone shed some light on the hold-up?" Back in April of 2002, JPEG2000 was "coming soon", and it was touted as being the "the future of imaging", but after that the hype seems to have dried up. What happened to this promising specification? Did another format surpass it (PNG, perhaps)?
I can't speak to the standard, but I can cover our experiences using Jpeg2000. In early 2001, the Second Life team did an evaluation of available still image compression schemes in order to determine whether an off-the-shelf solution would meet our requirements of providing flawless visual reproduction at 10:1 compression while preserving chroma at compressions of 100:1 or more, allowing progressive streaming in order to handle level of detail and mipmapping, and be high performance enough to allow for multiple packet decodes per game frame. We went into the search assuming that we would end up having to write out own compression scheme and were pleasantly surprised by the performance of Jpeg2000. We selected the Kakadu libraries for Jpeg2000 compression and decompression and have been happily using them for 3 years on Linux, Mac, and Windows.
It is a shame that Jpeg2000 hasn't seen wider adoption, as it is visually far superior to Jpeg at similar compression levels, especially in reduced "ringing" around high-frequency edges, and its ability to handle progressive streaming is incredibly useful in interactive environments. In Second Life's case, images as large as 2048x2048 are delivered interactively to the client viewer, with a single packet providing enough detail for distant textures. As the user approaches textures, additional packets are delivered to the client, providing a progressive increase in detail with very low latency, thanks to Jpeg2000's ability to deliver fine-grained increases. Kakadu's high performance has also been critical, since many scenes in Second Life have thousands of different textures in view because of user created and uploaded textures.