Amsterdam It's already past the middle of 2005, and you may be wondering whatever happened to the JPEG2000 standard, four years after ratification.
Rest assured, this wavelet-based imagecompression technology, established as an international standard in January 2001, is alive and well, although it has not made it into volume consumer digital still cameras, the original objective of many JPEG2000 proponents.
Thomson last week unveiled at the International Broadcast Convention here what it called the industry's first professional high-definition camcorder embracing JPEG2000 image compression.
The HD camcorder, designed for the broadcast industry, uses two identical JPEG2000 encode and decode chips from Analog Devices Inc., the ADV202 parts. Thomson's adoption of JPEG2000 in a camcorder represents a big boost for the fledgling standard.
In contrast to JPEG and MPEG, both broadly accepted in digital still cameras, DVDs and set-top applications, JPEG2000's only inroads thus far have been in high-end, relatively vertical imaging products including digital cinema, medical diagnostic equipment and the archiving of satellite photos for the U.S. government.
The essence of wavelet forms-based JPEG2000 is "encode it once and decode it in many ways," at various bit rates, said Bill Bucklen, product line director for Analog Devices' high-speed signal-processing group. The JPEG2000 file lets users receive and process only the information necessary to match the transmission speed or display resolutions, while making no changes in the original file.
Compared with conventional DCT-based codecs, JPEG2000 is designed to offer several improvements. They include higher resolution; scalability to deliver image content that vary in quality and resolution from within the same file; and error resiliency for image transmission in noisy environments.
With Thomson's Grass Valley Infinity Digital Media Camcorder, HD footage shot and compressed in JPEG2000 can be transmitted in a lower resolution without creating a new file thus allowing producers to do off-line processing remotely in a compressed frame. MPEG-based solutions would require first decoding the original file and then re-encoding it in a lower-resolution file before sending it. But JPEG2000 lets producers edit the film for broadcast in a single file.
This allows them to avoid a generational loss resulting from transcoding and to eliminate the extra step of duplicating the file.
"This will significantly streamline the whole process," said ADI's Bucklen. He made it clear, however, that the broadcast industry will be using JPEG2000 in editing suites, rather than adopting it for broadcasting signals.
As broadcasters transition from standard to high definition, "the problem has gotten much harder for studios," he noted, when they handle HD files in postproduction processes. Due to the "symmetrical" nature of the JPEG2000 codec, which requires equally low processing power for both encoding and decoding, JPEG2000 is "ideal for real-time HD encoding," Bucklen added.