Removing blur from an image

1. On a computing device, a method of deconvoluting a blurred image via a non-blind deconvolution, the method comprising:

iteratively downsampling the blurred image to form a blurred image pyramid comprising images of a plurality of different resolution scales;

at a lower resolution scale in the blurred image pyramid, deconvoluting a lower resolution image according to a Bilateral Richardson-Lucy (BRL) deconvolution process in which a bilateral range/spatial filter is employed to form a lower resolution deconvoluted image;

upsampling the lower resolution deconvoluted image to form an upsampled image; and

at a higher resolution scale in the blurred image pyramid, deconvoluting a higher resolution image according to the BRL deconvolution process.

2. The method of claim 1 , further comprising employing a filter reliant on an external guide image in addition to the bilateral range/spatial filter.

3. The method of claim 2 , wherein the external guide image comprises a previously deconvoluted image from a same scale in the blurred image pyramid.

4. The method of claim 2 , wherein the external guide image comprises an image that is upsampled from a previously deconvoluted image at a next-lowest resolution scale in the blurred image pyramid.

5. The method of claim 2 , wherein the JBRL deconvolution process proceeds as following:

I

t

+

1

=

I

t

1

+

λ

⁢

∇

⁢

E

B

⁡

(

I

t

)

⁡

[

K

*

⊗

B

(

I

t

⊗

K

)

]

wherein I t+1 is a value of a pixel in the updated image, I t is a value of the pixel in a current image, B is a value of the pixel in the original degraded image, K is a blur kernel, K* is an adjoint of K, λ is a regularization strength, and ∇E B comprises the bilateral range/spatial filter and the filter reliant on the external guide image.

6. The method of claim 5 , wherein ∇E B comprises a high pass filter as an additional filter for the BRL deconvolution process in an intra-scale deconvolution at each scale in the blurred image pyramid.

7. On a computing device, a method of deconvoluting an original blurred image to form an updated image, the method comprising:

iteratively downsampling the original blurred image to form a blurred image pyramid comprising i layers of blurred images of progressively lower resolution scales, wherein i=0 is a lowest-resolution scale;

for each resolution scale 0 to i:

performing an inter-scale Bilateral Richardson-Lucy (BRL) deconvolution process in which a bilateral range/spatial filter is employed;

performing one or more intra-scale BRL deconvolution processes in which the bilateral range/spatial filter is employed to form an intra-scale deconvoluted image; and

upsampling the intra-scale deconvoluted image.

8. The method of claim 7 , further comprising, for scales 1-n, employing an additional filter reliant on an external guide image.

9. The method of claim 8 , wherein the external guide image comprises an image upsampled from a next-lowest resolution scale after deconvolution at the next-lowest resolution scale.

10. The method of claim 8 , wherein the external guide image comprises a previously-deconvoluted image from a same resolution scale.

11. The method of claim 7 , wherein upsampling the intra-scale deconvoluted image comprises performing a bicubic or bilinear interpolation to form an intermediate upscaled image.

12. The method of claim 7 , further comprising employing a high pass filter as an additional filter for one or more intra-scale BRL deconvolution processes.