Still pixel detection using multiple windows and thresholds

A method of detecting still pixels in a video stream having a plurality of fields including an early field having an early current pixel and a late field having a late current pixel, the method comprising:

• defining a first window containing a first plurality of pixels of the late field with a noise reduction unit, wherein the first plurality of pixels includes the late current pixel;
• calculating a pixel pair difference for each pixel in the first window to generate a plurality of pixel pair differences with the noise reduction unit;
• summing the absolute value of each pixel pair difference that is greater than a summation threshold to create a correlation sum of the first window with the noise reduction unit;
• comparing the correlation sum of the first window with a correlation threshold with the noise reduction unit, wherein the late current pixel is classified as a still pixel when the correlation sum divided by a size of the first window is less than or equal to the correlation threshold.

A method of detecting still pixels in a video stream having a plurality of fields including an early field having an early current pixel and a late field having a late current pixel, the method comprising:

• defining a first window containing a first plurality of pixels of the late field with a noise reduction unit, wherein the first plurality of pixels includes the late current pixel;
• calculating a pixel pair difference for each pixel in the first window to generate a plurality of pixel pair differences with the noise reduction unit;
• comparing an absolute value of each pixel pair difference with a difference threshold with the noise reduction unit, wherein the late current pixel is classified as a non-still pixel when the absolute value of any pixel pair difference of the first window is greater than the difference threshold;
• summing the absolute value of each pixel pair difference to create a correlation sum of the first window with the noise reduction unit;
• comparing the correlation sum of the first window with a correlation threshold with the noise reduction unit, wherein the late current pixel is classified as a still pixel when the correlation sum divided by a size of the first window is less than or equal to the correlation threshold.

A system of detecting still pixels in a video stream having a plurality of fields including an early field having an early current pixel and a late field having a late current pixel, the system comprising:

• means for defining a first window of pixels of the late field, wherein the first window includes the late current pixel;
• means for performing a first window still pixel test using the pixels of the first window;
• wherein the means for performing a first window still pixel test includes
• means for calculating a pixel pair difference for each pixel in the first window to generate a plurality of pixel pair differences;
• and
• means for comparing an absolute value of each pixel pair difference with a difference threshold, wherein the late current pixel fails the first window still pixel test when the absolute value of any pixel pair difference of the first window is greater than the difference threshold;
• means for defining a second window of pixels of the late field, wherein the second window includes the late current pixel;
• and
• means for performing a second window still pixel test using the pixels of the second window.

A system of detecting still pixels in a video stream having a plurality of fields including an early field having an early current pixel and a late field having a late current pixel, the system comprising:

• means for defining a first window containing a first plurality of pixels of the late field, wherein the first plurality of pixels includes the late current pixel;
• means for calculating a pixel pair difference for each pixel in the first window to generate a plurality of pixel pair differences;
• means for summing the absolute value of each pixel pair difference that is greater than a summation threshold to create a correlation sum of the first window;
• means for comparing the correlation sum of the first window with a correlation threshold, wherein the late current pixel is classified as a still pixel when the correlation sum divided by a size of the first window is less than or equal to the correlation threshold.

A system of detecting still pixels in a video stream having a plurality of fields including an early field having an early current pixel and a late field having a late current pixel, the system comprising:

• means for defining a first window containing a first plurality of pixels of the late field, wherein the first plurality of pixels includes the late current pixel;
• means for calculating a pixel pair difference for each pixel in the first window to generate a plurality of pixel pair differences;
• means for comparing an absolute value of each pixel pair difference with a difference threshold, wherein the current pixel is classified as a non-still pixel when the absolute value of any pixel pair difference of the first window is greater than the difference threshold;
• means for summing the absolute value of each pixel pair difference to create a correlation sum of the first window;
• means for comparing the correlation sum of the first window with a correlation threshold, wherein the late current pixel is classified as a still pixel when the correlation sum divided by a size of the first window is less than or equal to the correlation threshold.