Motion Estimation from a Single Blurred Image · 2009. 4. 14. · Motion Estimation from a Single Blurred Image ... Taking satisfactory pictures at low-light conditions is challenging

Dipartimento di Elettronica e Informazione

Motion Estimation from a Single Blurred Image

Image Restoration: De-Blurring• Build a “Blur Map”• Adapt Existing De-blurring Techniques to real blurred images


Analysis, Reconstruction and 3D reconstruction from a single blurred image

Example

More info:[email protected]


Blurred Image Analysis and Restoration

Restoration of Radial Blur



Restoration of Radial blur



Rotational Blur Estimation From a single Image







Blur is Space Variant

Estimation of • 3d camera rotation

axis

• Angular speed

From a single image



And then….

Blur Removal

Denoising!

i.e. a restoration algorithm



Restoration of Rotational Blur



Restoration of Rotational Blur


Blur Analysis and Restoration -- Projects

Implement a Rotational Blur Removal algorithm that takes into account also noise.

Deblurring on spherical surfaces

More info:[email protected]://tinyurl.com/3wqmeo


Blur classification in a single blurred image

Given a Blurred Image, determine if the image is blurred

and in that case, if the blur is due to

object motion

camera shake

out of focus

Depth of field

These information are necessary for image restoration


Depth of Field – Blurred Object Segmentation






Blur classification and Segmentation -- Projects

Improve the segmentation algorithm, exploiting image priors

Embed the blur estimation algoirthm

Restoration: blur inversion + noise removal

Blur Classification

More info:

giacomo.

boracchi

@polimi.

it


Low-light Image Restoration

Taking satisfactory pictures at low-light conditions is challenging.

Pictures acquired with a short exposure-time have low SNR and are very noisy because of a high gain (ISO number).






Introduction

Taking satisfactory pictures at low-light conditions is challenging.

Pictures acquired with a short exposure-time have low SNR and are very noisy because of a high gain (ISO number).

Typically the exposure time is increased in order to improve the SNR of the acquired image.

But this also increases the risk of blur, because of movements occurring in the extended exposure.





A variety of solutions:• Lenses Stabilization • Different Acquisition Strategies

In particular [Tico06] and [Yuan07] proposed two methods that use differently exposed images• one with a long exposure time (blurred but with negligible noise)• one with a short exposure time (noisy but with negligible blur)

The noisy image is used to estimate the blur PSF allowing to restore the blurred image (deblurring)

[Tico06] Tico, M., "Estimation of motion blur point spread function from differently exposed image frames," Proc. 14th Eur. Signal Process. Conf., EUSIPCO 2006, Florence, Italy, September 2006[Yuan07] Yuan, L., J. Sun, L. Quan, and H.-Y. Shum, "Image deblurring with blurred/noisy image pairs," ACM Trans. Graph., vol. 26, no. 3, July 2007



Acquire a sequence of short exposure images (frames) and jointly denoise them, using a video denoising algorithm


BM3D DenoisingMore info:[email protected]://www.cs.tut.fi/~foi/BM-3D-PRESENT/index.html

mailto:[email protected]


BM3D – Aggregation






Denoising vs Deblurring

Long exposure, camera shaked image



One of the short exposure, noisy image



A detail from restored with Tico et al. algorithm

Visible artifacts due to mismatchesbetween assumed blur model (invariant PSF, linearity) and real blur.



A detail from image

restored with

our algorithm

There are less artifacts.

Modeling is accurate.

Denoising is less ill-posed than deblurring.



A detail from imagerestored with Tico et al. algorithm



A detail from image restored with our algorithm

Not all details can be recovered by denoising because SNR is too low.



A detail from the noisy image









More info:[email protected]://tinyurl.com/4pcb6v

mailto:[email protected]

Documents

Motion Estimation from a Single Blurred Image · 2009. 4. 14. · Motion Estimation from a Single Blurred Image ... Taking satisfactory pictures at low-light conditions is challenging