Method and apparatus for MPEG artifacts reduction
First Claim
1. A method of reducing mosquito noise in an image frame of a video signal, the method comprising:
- providing a window of the image frame, the window including a plurality of pixel values;
subtracting a selected one of the pixel values from the pixel values in the window to define a modified window of pixel value differences;
computing a local mean (DC) value based on the pixel value differences;
computing a mosquito noise reduction value based on the pixel value differences;
computing an artifact attenuation factor as a function of a dynamic range measure of the pixel value differences; and
computing a weighted sum of the mosquito noise reduction value and the local mean value, applying the artifact attenuation factor, and the selected pixel value, to generate a modified pixel value.
2 Assignments
0 Petitions
Accused Products
Abstract
Disclosed herein are methods and apparatus, including computer program products, implementing and using techniques for reducing mosquito noise in an image frame of a video signal. A window of the image frame is provided. The window includes a plurality of pixel values. One of the pixel values is selected from the pixel values in the window to define a modified window of pixel value differences. A local mean (DC) value is computed based on the pixel value differences. A mosquito noise reduction value is also computed based on the pixel value differences. An artifact attenuation factor is computed as a function of a dynamic range measure of the pixel value differences. A weighted sum of the mosquito noise reduction value and the local mean value, applying the artifact attenuation factor, and the selected pixel value, is computed to generate a modified pixel value.
-
Citations
19 Claims
-
1. A method of reducing mosquito noise in an image frame of a video signal, the method comprising:
-
providing a window of the image frame, the window including a plurality of pixel values;
subtracting a selected one of the pixel values from the pixel values in the window to define a modified window of pixel value differences;
computing a local mean (DC) value based on the pixel value differences;
computing a mosquito noise reduction value based on the pixel value differences;
computing an artifact attenuation factor as a function of a dynamic range measure of the pixel value differences; and
computing a weighted sum of the mosquito noise reduction value and the local mean value, applying the artifact attenuation factor, and the selected pixel value, to generate a modified pixel value. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. An apparatus for reducing mosquito noise in an image frame of a video signal, the apparatus comprising:
-
a windowing module configured to provide a window of the image frame, the window including a plurality of pixel values;
a subtraction module configured to subtract a selected one of the pixel values from the pixel values in the window to define a modified window of pixel value differences;
a local mean determination module configured to compute a local mean (DC) value based on the pixel value differences;
a mosquito noise reduction module configured to perform a mosquito noise reduction operation on the pixel value differences in the modified window to generate a mosquito noise reduction value;
a smooth attenuation module configured to compute an artifact attenuation factor as a function of a dynamic range measure of the pixel value differences; and
an output module configured to compute a weighted sum of the mosquito noise reduction value and the local mean value, applying the artifact attenuation factor, and the selected pixel value, to generate a modified pixel value. - View Dependent Claims (10, 11)
-
-
12. A computer program product, stored on a processor readable medium, comprising instructions operable to cause a computer to perform a method of reducing mosquito noise in an image frame of a video signal, the method comprising:
-
providing a window of the image frame, the window including a plurality of pixel values;
subtracting a selected one of the pixel values from the pixel values in the window to define a modified window of pixel value differences;
computing a local mean (DC) value based on the pixel value differences;
computing a mosquito noise reduction value based on the pixel value differences;
computing an artifact attenuation factor as a function of a dynamic range measure of the pixel value differences; and
computing a weighted sum of the mosquito noise reduction value and the local mean value, applying the artifact attenuation factor, and the selected pixel value, to generate a modified pixel value. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19)
-
Specification