Browse Definitions:
Definition

wavelet

Contributor(s): Fred Calm

A wavelet is a mathematical function useful in digital signal processing and image compression . The use of wavelets for these purposes is a recent development, although the theory is not new. The principles are similar to those of Fourier analysis, which was first developed in the early part of the 19th century.

In signal processing, wavelets make it possible to recover weak signals from noise . This has proven useful especially in the processing of X-ray and magnetic-resonance images in medical applications. Images processed in this way can be "cleaned up" without blurring or muddling the details.

In Internet communications, wavelets have been used to compress images to a greater extent than is generally possible with other methods. In some cases, a wavelet-compressed image can be as small as about 25 percent the size of a similar-quality image using the more familiar JPEG method. Thus, for example, a photograph that requires 200 KB and takes a minute to download in JPEG format might require only 50 KB and take 15 seconds to download in wavelet-compressed format.

Wavelet compression works by analyzing an image and converting it into a set of mathematical expressions that can then be decoded by the receiver. A wavelet-compressed image file is often given a name suffix of "WIF." Either your browser must support these files or it will require a plug-in program to read the fles.

Wavelet compression is not yet widely used on the Web. The most common compressed image formats remain the Graphics Interchange Format ( GIF ), used mainly for drawings, and JPEG, used mainly for photographs.

This was last updated in April 2005

Join the conversation

1 comment

Send me notifications when other members comment.

By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy

Please create a username to comment.

You might consider updating your download times here... What is it 1990?
Cancel

-ADS BY GOOGLE

File Extensions and File Formats

Powered by:

SearchCompliance

  • internal audit (IA)

    An internal audit (IA) is an organizational initiative to monitor and analyze its own business operations in order to determine ...

  • pure risk (absolute risk)

    Pure risk, also called absolute risk, is a category of threat that is beyond human control and has only one possible outcome if ...

  • risk assessment

    Risk assessment is the identification of hazards that could negatively impact an organization's ability to conduct business.

SearchSecurity

  • biometrics

    Biometrics is the measurement and statistical analysis of people's unique physical and behavioral characteristics.

  • principle of least privilege (POLP)

    The principle of least privilege (POLP), an important concept in computer security, is the practice of limiting access rights for...

  • identity management (ID management)

    Identity management (ID management) is the organizational process for identifying, authenticating and authorizing individuals or ...

SearchHealthIT

SearchDisasterRecovery

  • business continuity and disaster recovery (BCDR)

    Business continuity and disaster recovery (BCDR) are closely related practices that describe an organization's preparation for ...

  • business continuity plan (BCP)

    A business continuity plan (BCP) is a document that consists of the critical information an organization needs to continue ...

  • call tree

    A call tree -- sometimes referred to as a phone tree -- is a telecommunications chain for notifying specific individuals of an ...

SearchStorage

SearchSolidStateStorage

  • hybrid hard disk drive (HDD)

    A hybrid hard disk drive is an electromechanical spinning hard disk that contains some amount of NAND Flash memory.

Close