One key issue (at least for the PC user, rather than the Apple Mac) has been the difficulty in matching outputs from scanners, digital cameras and other capture devices to monitor screens and printers. Whilst there is now considerable technological progress in this area, and it is certainly possible to work in a colour calibrated environment for a small range of a user's equipment, it is still almost impossible to deal with many of the files a user receives effectively and accurately. The arrival of JPEG 2000 is set to change this situation, as a mandatory part of the standard requires equipment generating JPEG 2000 files to define accurately how colour is treated within the image file.
As printers and scanners become more sophisticated, so their capabilities increase. A few year's ago, 600 dpi would have been regarded as high quality for a laser or inkjet printer. Today printers capable of photo quality reproduction and costing less than 100$ can commonly have printing resolutions as high as 4,800 by 1,200. Scanners too used to be barely capable of more quality than a facsimile machine - now most scanners with use at least 36 bits for colour representation, and many have 48 or more. Their output has to be pre-processed to bring it down to the 24 bits that most PC screen monitors and displays support, or that are used in the vast majority of photographic image file formats.
JPEG 2000 can support these kind of resolutions easily - more importantly, because of the way the standard has been designed, it is easy to extract a lower resolution version of the image from a JPEG 2000 codestream for initial viewing or processing, whilst keeping the full image for subsequent printing or archival storage. In addition, as storage media fills up, it becomes feasible to start to compress the stored ultra high quality images to make more room, either selectively or automatically. A 35 mm slide from a quality camera for example might be expected to be roughly equivalent in quality to a 48 bit image at about 12 Mpixels - say 72 Mbytes. Using any form of truly lossless compression (even JPEG 2000!), this is likely to still require over 36 Mbytes in the digital domain.
A next generation digital camera, even with a gigabyte of storage would only hold around a couple of dozen such images (assuming technology improves to the extent that they can be captured and saved to digital media sufficiently fast). Even a PC with over 100 Gbytes of storage would not be able to hold very large numbers of such high quality images. It therefore becomes important to be able to start to compress such images selectively, either automatically, or under user selection, and here JPEG 2000 has many useful benefits. Users could selectively crop, reduce bit depth or resolution, or choose to compress these images so that many hundreds of such images could be saved on suitable media - whilst retaining the option for key images to preserve as much of the quality as is required.
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