Set partitioning in hierarchical trees (SPIHT)
is an
image
An image or picture is a visual representation. An image can be Two-dimensional space, two-dimensional, such as a drawing, painting, or photograph, or Three-dimensional space, three-dimensional, such as a carving or sculpture. Images may be di ...
compression algorithm
In information theory, data compression, source coding, or bit-rate reduction is the process of encoding information using fewer bits than the original representation. Any particular compression is either lossy or lossless. Lossless compression ...
that exploits the inherent similarities across the subbands in a
wavelet decomposition of
an image. The algorithm was developed by Brazilian engineer Amir Said with William A. Pearlman in 1996.
General description
The algorithm
code
In communications and information processing, code is a system of rules to convert information—such as a letter, word, sound, image, or gesture—into another form, sometimes shortened or secret, for communication through a communicati ...
s the most important
wavelet transform coefficients
In mathematics, a coefficient is a multiplicative factor involved in some term of a polynomial, a series, or any other type of expression. It may be a number without units, in which case it is known as a numerical factor. It may also be a ...
first, and transmits the bits so that an increasingly refined copy of the original image can be obtained progressively.
See also
*
Embedded Zerotrees of Wavelet transforms (EZW)
*
Wavelet
A wavelet is a wave-like oscillation with an amplitude that begins at zero, increases or decreases, and then returns to zero one or more times. Wavelets are termed a "brief oscillation". A taxonomy of wavelets has been established, based on the n ...
References
{{Compression Methods
Image compression
Wavelets
Brazilian inventions
Data compression