System and Method for Video Quality Parametric Tests

• US 20110096170A1
• Filed: 10/23/2009
• Published: 04/28/2011
• Est. Priority Date: 10/23/2009
• Status: Active Grant

• Current Assignee: Contec LLC (Contec LLC /Management/)
• Original Assignee: Contec LLC (Contec LLC /Management/)
• Inventors: Villanueva, Rafael, Miranda, Vicente
• Granted Patent: US 8,310,548 B2
• Time in Patent Office: Days
• US Class Current: 348/187
• CPC Class Codes: H04N 17/00 Diagnosis, testing or measuring for television systems or their details
• CPC Class Codes: H04N 17/004 for digital television systems

Abstract

A method and system for automatically evaluating the quality of a signal transmitted by an imaging device. The amount of noise in the video signal is analyzed using an algorithm that does not require comparison to a template signal. The results of the algorithm determine whether the signal meets a pre-determined threshold value for signal quality.

Claims

1. A method for measuring the amount of noise in a video image comprising:

receiving a signal from an imaging device;

extracting a luma component from a color image;

applying a filter to compute the second derivatives of an image;

determine a ratio of noise pixels to total pixels; and

compare the ratio to a pre-determined ratio.

2. The method of claim 1, wherein the filter is a Laplace filter.

3. The method of claim 1, wherein the pixels are binarized prior to determining the ratio of noise pixels to total pixels.

4. The method of claim 1, wherein the video signal comprises smooth areas in the background of the images.

5. The method of claim 1, wherein the video signal comprises a color bar pattern.

6. The method of claim 1, wherein if the ratio exceeds the pre-determined ratio the signal is rejected.

7. The method of claim 1, wherein if the ratio is less than the pre-determined ratio the signal is accepted.

8. The method of claim 1, wherein if the ratio exceeds the pre-determined ratio, the imaging device is determined to be faulty.

9. An apparatus for determining the functioning of an imaging device comprising;

a processor;

memory, coupled to the processor, wherein the memory is configured to allow the processor to;

obtain a video signal;

extract a luma component from the video signal;

filter the luma component to determine a ratio of noise pixels to total pixels;

compare the ratio or noise pixels to total pixels to a pre-determined ratio; and

wherein if the processor determines that the ratio of noise pixels to total pixels exceeds the pre-determined ratio, the processor emits an error code indicating that the imaging device is non-functioning.

10. The apparatus of claim 9, wherein the filter is a Laplace filter.

11. The apparatus of claim 9, wherein the filter is an omnidirectional filter.

12. The apparatus of claim 9, wherein the filter recognizes small changes in contrast around pixels.

13. The apparatus of claim 9, wherein the luma component is the Y signal of a color image.

14. A system for video quality assessment comprising:

a video imaging device;

a testing device for measuring the amount of noise in a video image;

wherein the testing device comprises logic that enables determination of the amount of noise in a video picture by evaluating the contrast between neighboring pixels and calculating the ratio of noisy pixels to total pixels.

15. The system of claim 14, wherein the contrast between neighboring pixels is determined by applying a Laplace filter.

16. The system of claim 14, wherein the contrast between neighboring pixels is determined by applying an omnidirectional filter.

17. The system of claim 14, wherein the video imaging device sends a signal to the testing device.

18. The system of claim 14, wherein the contrast between pixels is determined in the Y signal.

19. The system of claim 14, comprising logic to control an RF attenuation of a video image signal to induce noise in the video imaging device.