Removing blur from an image

• US 8,750,643 B2
• Filed: 03/25/2013
• Issued: 06/10/2014
• Est. Priority Date: 09/24/2008
• Status: Active Grant

• Current Assignee: Zhigu Holdings Limited
• Original Assignee: Microsoft Corporation
• Inventors: Sun, Jian, Shum, Heung-Yeung, Yuan, Lu, Quan, Long
• Primary Examiner(s): Chu, Randolph I
• Application Number:
  US13/850,213
• Publication Number:
  US 20130223754A1
• Time in Patent Office: 442 Days
• Field of Search: None
• US Class Current: 382/279
• CPC Class Codes: G06T 2207/20016 Hierarchical, coarse-to-fine, multiscale or multiresolution image processing; Pyramid transform
• CPC Class Codes: G06T 2207/20028 Bilateral filtering
• CPC Class Codes: G06T 5/73 Deblurring; Sharpening

Abstract

Embodiments related to the removal of blur from an image are disclosed. One disclosed embodiment provides a method of performing an iterative non-blind deconvolution of a blurred image to form an updated image. The method comprises downsampling the blurred image to form a blurred image pyramid comprising images of two or more different resolution scales, downsampling a blur kernel to form a blur kernel pyramid comprising kernels of two or more different sizes, and deconvoluting a selected image in the blurred image pyramid according to a Richardson-Lucy deconvolution process in which a bilateral range/spatial filter is employed.

Claims

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:

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.