Color interpolation method of image sensor

Abstract

A color interpolation method of an image sensor including a pixel array which green, red and blue pixels are arrayed in Bayer pattern is provided. The method includes: calculating a first average value of first values filtered by green pixels on even rows and a second average value of a second values filtered by green pixels on odd rows; comparing a value difference between the first average value and the second average value with a standard value; and performing one of a normal interpolation method and a compensation interpolation method with respect to the values filtered by the green pixels according to the comparison.

What is claimed is: 
     
       1. A color interpolation method of an image sensor including a pixel array which green, red and blue pixels are arrayed in Bayer pattern, the color interpolation method comprising:
 calculating a first average value of first values filtered by green pixels on even rows and a second average value of a second values filtered by green pixels on odd rows; 
 calculating an average value of a noise of black pixels which do not receive image information; 
 comparing a value difference between the first average value and the second average value with the average value of the noise of the black pixels; and 
 performing selectively, with an image signal processor, one of a normal interpolation method and a compensation interpolation method with respect to the values filtered by the green pixels based on a result of the comparison. 
 
     
     
       2. The color interpolation method of  claim 1 , wherein at the selective performing of one of the normal interpolation method and the compensation interpolation method with respect to the values filtered by the green pixels based on the result of the comparison, if the value difference between the first average value and the second average value is greater that than the average value of the noise of the black pixels, the compensation interpolation method is employed. 
     
     
       3. The color interpolation method of  claim 2 , wherein the compensation interpolation method includes:
 performing a compensation interpolation operation with respect to the first values; 
 performing a compensation interpolation operation with respect to the second values; and 
 calculating an average value of values resulted from performing the compensation operations with respect to the first values and the second values, wherein the average value is applied as an interpolation value of the green pixels. 
 
     
     
       4. The color interpolation method of  claim 1 , wherein at the selective performing of one of the normal interpolation method and the compensation interpolation method with respect to the values filtered by the green pixels based on the result of the comparison, if the value difference between the first average value and the second average value is smaller than the average value of the noise of the black pixels, the normal interpolation method is employed. 
     
     
       5. The color interpolation method of  claim 1 , wherein the normal interpolation method uses one of a mean value and an average filter. 
     
     
       6. A method, comprising:
 calculating a first average value of first values from green pixels on even rows of a pixel array and a second average value of second values from green pixels on odd rows of the pixel array;   calculating an average value of a noise of black pixels, which do not receive image information;   comparing a value difference between the first average value and the second average value with the average value of the noise of the black pixels; and   performing selectively, with an imaging device, a compensation interpolation method with respect to the first and second values from the green pixels based on a result of the comparison.   
     
     
       7. The method of claim 6, wherein said performing selectively a compensation interpolation method comprises performing the compensation method if the value difference between the first average value and the second average value is greater than the average value of the noise of black pixels. 
     
     
       8. The method of claim 6, wherein said performing the compensation interpolation method comprises:
 performing a compensation interpolation operation with respect to the first values;   performing a compensation interpolation operation with respect to the second values;   averaging values resulting from said performing a compensation interpolation operation with respect to the first values and said performing a compensation interpolation operation with respect to the second values to obtain another average value; and   applying the another average value as an interpolation value of the green pixels.   
     
     
       9. The method of claim 6, further comprising performing a normal interpretation method with respect to the values from the green pixels if the value difference between the first average value and the second average value is smaller than the average value of the noise of the black pixels. 
     
     
       10. The method of claim 9, wherein the normal interpolation method uses a mean value. 
     
     
       11. The method of claim 9, wherein the normal interpolation method uses an average filter. 
     
     
       12. An image sensor, comprising:
 a pixel array comprising a plurality of pixels configured to receive image information and a plurality of black pixels configured to not receive image information; and   circuitry configured to:
 calculate a first average value of first values from green pixels on even rows of the pixel array and a second average value of second values from green pixels on odd rows of the pixel array; 
 calculate an average value of a noise of the plurality of black pixels; 
 compare a value difference between the first average value and the second average value with the average value of the noise of the black pixels; and 
 perform selectively a compensation interpolation method with respect to the first and second values from the green pixels based on a result of the comparison. 
   
     
     
       13. The image sensor of claim 12, wherein the circuitry is further configured to perform the compensation interpolation method if the value difference between the first average value and the second average value is greater than the average value of the noise of black pixels. 
     
     
       14. The image sensor of claim 12, wherein, in response to performing the compensation interpolation method, the circuitry is further configured to:
 perform a compensation interpolation operation with respect to the first values;   perform a compensation interpolation operation with respect to the second values;   average values resulting from the compensation interpolation operation with respect to the first values and said the compensation interpolation operation with respect to the second values to obtain another average value; and   apply the another average value as an interpolation value of the green pixels.   
     
     
       15. The image sensor of claim 12, wherein the circuitry is further configured to perform a normal interpretation method with respect to the values from the green pixels if the value difference between the first average value and the second average value is smaller than the average value of the noise of the black pixels. 
     
     
       16. The image sensor of claim 15, wherein the circuitry is further configured to use a mean value when performing the normal interpolation method. 
     
     
       17. The image sensor of claim 15, wherein the circuitry is further configured to use an average filter when performing the normal interpolation method. 
     
     
       18. The image sensor of claim 12, wherein the plurality of pixels are formed in a Bayer pattern comprising red pixels, green pixels, and blue pixels. 
     
     
       19. The image sensor of claim 12, further comprising a metal layer configured to prevent the black pixels from receiving image information.