image reconstruction from non- uniformly sampled spectral data alfredo nava-tudela amsc 663, fall...

Post on 17-Jan-2016

215 Views

Category:

Documents

0 Downloads

Preview:

Click to see full reader

TRANSCRIPT

Image Reconstruction from Non-Uniformly Sampled Spectral

Data

Image Reconstruction from Non-Uniformly Sampled Spectral

Data

Alfredo Nava-Tudela

AMSC 663, Fall 2008

Midterm Progress Report

Advisor: John J. Benedetto

Alfredo Nava-Tudela

AMSC 663, Fall 2008

Midterm Progress Report

Advisor: John J. Benedetto

OutlineOutline

Background/Problem Statement Algorithm Database and Validation Test Results Future Work

Background/Problem Statement Algorithm Database and Validation Test Results Future Work

BackgroundBackground

Sometimes there is a need to reconstruct from spectral data an object in the spatial/time domain

For example, and image from an MRI machine

Sometimes there is a need to reconstruct from spectral data an object in the spatial/time domain

For example, and image from an MRI machine

Problem StatementProblem Statement

Given a two dimensional spectral data set, reconstruct an image in the spatial domain that matches as closely as possible that data set in the spectral domain

Given a two dimensional spectral data set, reconstruct an image in the spatial domain that matches as closely as possible that data set in the spectral domain

Problem StatementProblem Statement

In a real life application, the spectral data set is generated by some physical process

In our case, we generate artificial spectral data from a known high resolution image

We use a down-sampled version of that image to compare the goodness of our reconstruction

In a real life application, the spectral data set is generated by some physical process

In our case, we generate artificial spectral data from a known high resolution image

We use a down-sampled version of that image to compare the goodness of our reconstruction

The AlgorithmThe Algorithm

Stage one: Stage one:

The AlgorithmThe Algorithm

Stage two: Stage two:

The AlgorithmThe Algorithm

Stage three: Stage three:

The AlgorithmThe Algorithm

This algorithm corresponds to the direct solution of the linear system of equations presented in the project proposal

This has the drawback of having to store a potentially very big matrix

This algorithm corresponds to the direct solution of the linear system of equations presented in the project proposal

This has the drawback of having to store a potentially very big matrix

ValidationValidation

We select from a standard set of image processing images a subset

We select from a standard set of image processing images a subset

ValidationValidation

We convert the images to grayscale, in case they are in color

We convert the images to grayscale, in case they are in color

ValidationValidation

These are the images that we feed to our algorithm

Select the desired resolution for the reconstruction: 16 by 16 and 32 by 32

Higher resolutions take longer

These are the images that we feed to our algorithm

Select the desired resolution for the reconstruction: 16 by 16 and 32 by 32

Higher resolutions take longer

Test Results: BaboonTest Results: Baboon

Test Results: BaboonTest Results: Baboon

Test Results: BaboonTest Results: Baboon

Test Results: LenaTest Results: Lena

Test Results: LenaTest Results: Lena

Test Results: LenaTest Results: Lena

Test Results: PeppersTest Results: Peppers

Test Results: PeppersTest Results: Peppers

Test Results: PeppersTest Results: Peppers

Future WorkFuture Work

Allow arbitrary size input images, currently only square images processed

Implement algorithm that doesn’t store matrices

Write C++ code, explore parallelization Explore other ways to assess goodness of

reconstruction Explore different sampling geometries

Allow arbitrary size input images, currently only square images processed

Implement algorithm that doesn’t store matrices

Write C++ code, explore parallelization Explore other ways to assess goodness of

reconstruction Explore different sampling geometries

ReferencesReferences

Adi Ben-Israel and Thomas N. E. Greville. Generalized Inverses. Springer-Verlag, 2003.

John J. Benedetto and Paulo J. S. G. Ferreira. Moderm Sampling Theory: Mathematics and Applications. Birkhauser, 2001.

J. W. Cooley and J. W. Tukey. An algorithm for the machine computation of complex Fourier series. Math. Comp., 19:297-301, 1965.

E. H. Moore. On reciprocal of the general algebraic matrix. Bulletin of the American Mathematical Society, 26:85-100, 1920.

Diane P. O’Leary. Scientific computing with case studies. Book in preparation for publication, 2008.

Roger Penrose. On best approximate solution to linear matrix equations. Proceedings of the Cambridge Philosophical Society, 52:17-19, 1956.

Adi Ben-Israel and Thomas N. E. Greville. Generalized Inverses. Springer-Verlag, 2003.

John J. Benedetto and Paulo J. S. G. Ferreira. Moderm Sampling Theory: Mathematics and Applications. Birkhauser, 2001.

J. W. Cooley and J. W. Tukey. An algorithm for the machine computation of complex Fourier series. Math. Comp., 19:297-301, 1965.

E. H. Moore. On reciprocal of the general algebraic matrix. Bulletin of the American Mathematical Society, 26:85-100, 1920.

Diane P. O’Leary. Scientific computing with case studies. Book in preparation for publication, 2008.

Roger Penrose. On best approximate solution to linear matrix equations. Proceedings of the Cambridge Philosophical Society, 52:17-19, 1956.

top related