Method and system for calculating blur artifact in videos

• US 20100092100A1
• Filed: 10/14/2008
• Published: 04/15/2010
• Est. Priority Date: 10/14/2008
• Status: Active Grant

• Current Assignee: Interra Systems, Inc.
• Original Assignee: Interra Systems, Inc.
• Inventors: Madnani, Shekhar
• Granted Patent: US 8,150,191 B2
• Time in Patent Office: Days
• US Class Current: 382/255
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/30168 Image quality inspection
• CPC Class Codes: G06T 5/73 Deblurring; Sharpening
• CPC Class Codes: G06T 7/0002 Inspection of images, e.g. flaw detection

Abstract

A method and system for calculating a blur artifact in a video are disclosed. The video includes a series of frames captured at a predefined interval of time. The frames include one or more pixels. Calculating the blur artifact in the video includes identifying a focused area in a set of frames. Further, edges are detected in each of the frames. Furthermore, the blur artifact is calculated as a ratio of number of blurred pixels and total number edge pixels.

Claims

1. A method for calculating a blur artifact in a motion picture, the motion picture comprising one or more frames defined at a predefined interval of time, each of the one or more frames comprising one or more pixels, the method comprising:

detecting edges of the one or more pixels;

comparing the detected edges with a first predefined threshold;

determining one or more edge pixels, wherein the one or more edge pixels has the edges that exceed the first predefined threshold;

determining a set of pixels of the one or more pixels in a set of frames of the one or more frames, wherein the set of pixels is determined in the set of frames, wherein the set of pixels are the one or more pixels that exceed a second predefined threshold, and wherein a set of edge pixels of the one or more edge pixels is determined in the set of pixels;

determining one or more blurred edge pixels in the set of edge pixels, wherein the one or more blurred edge pixels are the set of edge pixels for which the edge spread exceeds a third predefined threshold; and

calculating the blur artifact as a ratio of a number of the one or more blurred edge pixels and a number of the one or more edge pixels in the set of edge pixels.

2. The method according to claim 1, wherein the edges are detected using an edge detection method selected from the group consisting of a Sobel operator method, a Canny edge detector method, and a Laplacian edge detector method.

3. The method according to claim 1, wherein detecting the edges comprises calculating one or more edge gradients of the detected edges.

4. The method according to claim 1, wherein the set of pixels is determined using a Sum of Modified Laplacian method.

5. The method according to claim 1, wherein calculating the blur artifact comprises:

calculating a perception threshold based on user input; and

comparing the calculated blur artifact with the perception threshold.

6. The method according to claim 5, wherein calculating the blur artifact comprises calculating duration of the blur artifact when the calculated blur artifact exceeds the perception threshold.

7. A system for calculating a blur artifact in a motion picture, the motion picture comprising one or more frames defined at a predefined interval of time, each of the one or more frames comprising one or more pixels, the system comprising:

a processor, the processor comprising;

an edge calculator, the edge calculator being capable of;

detecting edges of the one or more pixels; and

calculating edge spread of the one or more pixels;

a comparator, the comparator being capable of;

comparing the edges with a first predefined threshold; and

determining one or more edge pixels, wherein the one or more edge pixels have the edges that exceed the first predefined threshold;

a focus identifier, the focus identifier being capable of determining a set of pixels of the one or more pixels in a set of frames of the one or more frames, wherein the set of pixels is determined in the set of frames, wherein the set of pixels are the one or more pixels that exceed a second predefined threshold, and wherein a set of edge pixels of the one or more edge pixels is determined in the set of pixels; and

a blur artifact calculator, the blur artifact calculator being capable of;

determining one or more blurred edge pixels in the set of edge pixels, wherein the one or more blurred edge pixels are the set of edge pixels for which edge spread exceeds a third predefined threshold; and

calculating the blur artifact as a ratio of a number of the one or more blurred edge pixels and a number of the one or more edge pixels in the set of edge pixels.

8. The system according to claim 7, wherein the system further comprises an input module, the input module being capable of receiving the motion picture.

9. The system according to claim 7, wherein the system further comprises an output module, the output module being capable of displaying the calculated blur artifact.

10. The system according to claim 7, wherein the focus identifier is capable of determining the set of pixels using a Sum of Modified Laplacian method.

11. The system according to claim 7, wherein the blur artifact calculator further is capable of:

calculating a perception threshold based on user input, wherein the calculated blur artifact is compared with the perception threshold by the comparator; and

calculating duration of the blur artifact when the calculated blur artifact exceeds the perception threshold.

12. The system according to claim 11, wherein the edge calculator is capable of detecting the edges using an edge detection method selected from a group consisting of a Sobel operator, a Canny edge detector, and a Laplacian edge detector.

13. The system according to claim 12, wherein the edge calculator is further capable of calculating one or more edge gradients of the detected edges.

14. A computer program product for calculating a blur artifact in a motion picture, the motion picture comprising one or more frames defined at a predefined interval of time, each of the one or more frames comprising one or more pixels, the computer program product comprising instructions stored in a computer readable medium comprising:

program instructions for detecting edges of the one or more pixels;

program instructions for comparing the detected edges with a first predefined threshold;

program instructions for determining one or more edge pixels, wherein the one or more edge pixels has the edges that exceed the first predefined threshold;

program instructions for determining a set of pixels of the one or more pixels in a set of frames of the one or more frames, wherein the set of pixels is determined in the set of frames, wherein each of the set of pixels are the one or more pixels that exceed a second predefined threshold, and wherein a set of edge pixels of the one or more edge pixels is determined in the set of pixels;

program instructions for calculating edge spread of the set of edge pixels;

program instructions for determining one or more blurred edge pixels in the set of edge pixels, wherein the one or more blurred edge pixels are the set of edge pixels for which the edge spread exceeds a third predefined threshold; and

program instructions for calculating the blur artifact as a ratio of a number of the one or more blurred edge pixels and a number of the one or more edge pixels in the set of edge pixels.

15. The computer program product according to claim 14, wherein program instructions for detecting the edges comprise program instructions for calculating one or more edge gradients of the detected edges.

16. The computer program product according to claim 14, wherein the set of pixels are determined using program instructions for a Sum of Modified Laplacian method.

17. The computer program product according to claim 14, wherein program instructions for calculating the blur artifact comprise:

program instructions for calculating a perception threshold, based on user input;

program instructions for comparing the calculated blur artifact with the perception threshold; and

program instructions for calculating a duration of the blur artifact when the calculated blur artifact exceeds the perception threshold.