Improvements Over The 1992 JPEG Standard
- Superior compression performance
- At high bit rates, artifacts become nearly imperceptible, JPEG 2000 has a small machine-measured fidelity advantage over JPEG. At lower bit rates (e.g., less than 0.25 bits/pixel for grayscale images), JPEG 2000 has a much more significant advantage over certain modes of JPEG: artifacts are less visible and there is almost no blocking. The compression gains over JPEG are attributed to the use of DWT and a more sophisticated entropy encoding scheme.
- Multiple resolution representation
- JPEG 2000 decomposes the image into a multiple resolution representation in the course of its compression process. This representation can be put to use for other image presentation purposes beyond compression as such.
- Progressive transmission by pixel and resolution accuracy
- These features are more commonly known as progressive decoding and signal-to-noise ratio (SNR) scalability. JPEG 2000 provides efficient code-stream organizations which are progressive by pixel accuracy and by image resolution (or by image size). This way, after a smaller part of the whole file has been received, the viewer can see a lower quality version of the final picture. The quality then improves progressively through downloading more data bits from the source. The 1992 JPEG standard also has a progressive transmission feature but it is rarely used.
- Choice of lossless or lossy compression
- Like the Lossless JPEG standard, the JPEG 2000 standard provides both lossless and lossy compression compression in a single compression architecture. Lossless compression is provided by the use of a reversible integer wavelet transform in JPEG 2000.
- Random code-stream access and processing
- JPEG 2000 code streams are regions of interest that offer several mechanisms to support spatial random access or region of interest access at varying degrees of granularity. This way it is possible to store different parts of the same picture using different quality.
- Error resilience
- Like JPEG 1992, JPEG 2000 is robust to bit errors introduced by noisy communication channels, due to the coding of data in relatively small independent blocks.
- Flexible file format
- The JP2 and JPX file formats allow for handling of color-space information, metadata, and for interactivity in networked applications as developed in the JPEG Part 9 JPIP protocol.
- Side channel spatial information
- Full support for transparency and alpha planes.
Read more about this topic: JPEG 2000
Famous quotes containing the words improvements and/or standard:
“The improvements of ages have had but little influence on the essential laws of man’s existence: as our skeletons, probably, are not to be distinguished from those of our ancestors.”
—Henry David Thoreau (1817–1862)
“Liberty requires opportunity to make a living—a living decent according to the standard of the time, a living which gives a man not only enough to live by, but something to live for.”
—Franklin D. Roosevelt (1882–1945)