Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Reconstruction of Signal using Interpolation01:10

Reconstruction of Signal using Interpolation

Signal processing techniques are essential for accurately converting continuous signals to digital formats and vice versa. When a continuous signal is sampled with a period T, the resulting sampled signal exhibits replicas of the original spectrum in the frequency domain, spaced at intervals equal to the sampling frequency. To handle this sampled signal, a zero-order hold method can be applied, which creates a piecewise constant signal by retaining each sample's value until the next sampling...
Aliasing01:18

Aliasing

Accurate signal sampling and reconstruction are crucial in various signal-processing applications. A time-domain signal's spectrum can be revealed using its Fourier transform. When this signal is sampled at a specific frequency, it results in multiple scaled replicas of the original spectrum in the frequency domain. The spacing of these replicas is determined by the sampling frequency.
If the sampling frequency is below the Nyquist rate, these replicas overlap, preventing the original signal...
¹H NMR: Interpreting Distorted and Overlapping Signals01:02

¹H NMR: Interpreting Distorted and Overlapping Signals

Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are slanted or...
Linear Approximation in Frequency Domain01:26

Linear Approximation in Frequency Domain

Linear systems are characterized by two main properties: superposition and homogeneity. Superposition allows the response to multiple inputs to be the sum of the responses to each individual input. Homogeneity ensures that scaling an input by a scalar results in the response being scaled by the same scalar.
In contrast, nonlinear systems do not inherently possess these properties. However, for small deviations around an operating point, a nonlinear system can often be approximated as linear.
Upsampling01:22

Upsampling

Managing signal sampling rates is essential in digital signal processing to maintain signal integrity. A decimated signal, characterized by a reduced frequency range due to its lower sampling rate, can be upsampled by inserting zeros between each sample. This upsampling process expands the original spectrum and introduces repeated spectral replicas at intervals dictated by the new Nyquist frequency. To refine this zero-inserted sequence, it is passed through a lowpass filter with a cutoff...
Sampling Theorem01:15

Sampling Theorem

In signal processing, the analysis of continuous-time signals, denoted as x(t), often involves sampling techniques to convert these signals into discrete-time signals. This process is essential for digital representation and manipulation. A critical component in sampling is the train of impulses, characterized by the sampling interval and the sampling frequency. The relationship between these parameters and the original signal's properties dictates the success of the sampling process.

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Positive effects of anabolic steroids, vitamin D and calcium on muscle mass, bone mineral density and clinical function after a hip fracture. A randomised study of 63 women.

The Journal of bone and joint surgery. British volume·2002
Same author

An assessment of human liver-derived in vitro systems to predict the in vivo metabolism and clearance of almokalant.

Drug metabolism and disposition: the biological fate of chemicals·2001
Same author

Optimal processors for images with an arbitrary number of gray levels.

Journal of the Optical Society of America. A, Optics, image science, and vision·2000
Same author

How interactions between drugs and agarose-carrageenan hydrogels influence the simultaneous transport of drugs.

Journal of controlled release : official journal of the Controlled Release Society·1999
Same author

A new method for diffusion measurement in polymeric films based on a stacked sheet concept.

Pharmaceutical research·1996
Same author

Different effects on the expression of CYP7 and CYP27 in rabbit liver by cholic acid and cholestyramine.

Biochemical and biophysical research communications·1995

Related Experiment Video

Updated: Jul 7, 2026

Detection of Architectural Distortion in Prior Mammograms via Analysis of Oriented Patterns
13:44

Detection of Architectural Distortion in Prior Mammograms via Analysis of Oriented Patterns

Published on: August 30, 2013

Distortion-invariant filter for nonoverlapping noise.

H Sjöberg, B Noharet

    Applied Optics
    |February 28, 2008
    PubMed
    Summary
    This summary is machine-generated.

    A novel heuristic filter improves distortion-invariant filters for disjoint noise by combining optimum filters using a synthetic discriminant function (SDF) approach. This method enhances performance in low-contrast images with clutter.

    More Related Videos

    Medical-grade Sterilizable Target for Fluid-immersed Fetoscope Optical Distortion Calibration
    07:03

    Medical-grade Sterilizable Target for Fluid-immersed Fetoscope Optical Distortion Calibration

    Published on: February 23, 2017

    Related Experiment Videos

    Last Updated: Jul 7, 2026

    Detection of Architectural Distortion in Prior Mammograms via Analysis of Oriented Patterns
    13:44

    Detection of Architectural Distortion in Prior Mammograms via Analysis of Oriented Patterns

    Published on: August 30, 2013

    Medical-grade Sterilizable Target for Fluid-immersed Fetoscope Optical Distortion Calibration
    07:03

    Medical-grade Sterilizable Target for Fluid-immersed Fetoscope Optical Distortion Calibration

    Published on: February 23, 2017

    Area of Science:

    • Optical Engineering
    • Image Processing
    • Pattern Recognition

    Background:

    • Optimum filters are effective for noise reduction but can lack distortion invariance.
    • Synthetic Discriminant Function (SDF) approaches enable distortion-invariant filtering.
    • Disjoint noise presents challenges for traditional filtering techniques.

    Purpose of the Study:

    • To introduce a new heuristic filter for improved distortion-invariant performance against disjoint noise.
    • To adapt the optimum filter for disjoint noise using the SDF approach.
    • To evaluate the heuristic filter's effectiveness in challenging image conditions.

    Main Methods:

    • A new heuristic filter is developed by linearly combining multiple optimum filters.
    • The synthetic discriminant function (SDF) approach is employed to achieve distortion invariance.
    • The filter's performance is assessed on low-contrast images with non-overlapping clutter.

    Main Results:

    • The new heuristic filter demonstrates improved performance compared to the distortion-invariant optimum filter.
    • The filter effectively handles images with low contrast and high levels of non-overlapping clutter.
    • The summation technique allows for easy control of correlation peak height, enabling uniform filter response.

    Conclusions:

    • Simple heuristic methods can significantly enhance the performance of distortion-invariant filters for non-overlapping noise.
    • The proposed filter offers a practical solution for improving image analysis in cluttered environments.
    • This approach provides a flexible way to design filters for specific noise characteristics.