Better JPEG standard due in 2009
The Joint Photographic Experts Group, which standardized the original and still ubiquitous JPEG format, sent JPEG XR to the "final phases of standardization" after a vote at a January meeting, the group said Thursday. That means the standard's future is more certain.
"The committee expects the JPEG XR International Standard to be published later this year," the group said.
JPEG XR offers a few advantages over JPEG, according to Microsoft. For one thing, as the XR "extended range" abbreviation suggests, it offers greater dynamic range--the span between the brightest brights and darkest darks in a photo.
JPEG uses 8-bit encoding that provides 256 gradations, but JPEG XR can use 16 bits or more for finer distinctions and more editing flexibility. Newer digital SLRs typically record 14 bits data, and the hobbyist practice of combining multiple shots into a single high-dynamic range image also benefits from more bit depth.
Another advantage of JPEG XR is that it uses a more efficient compression algorithm that provides either twice the image quality as JPEG at the same file size, or half the file size for the same quality, according to Microsoft. And unlike JPEG, setting JPEG XR to record at its highest quality level loses no information to compression artifacts.