System, devices and/or processes for processing infrared pixel values
Example methods, apparatuses, and/or articles of manufacture are disclosed that may be implemented, in whole or in part, techniques to process pixel values sampled from a multi color channel imaging device. In particular, methods and/or techniques to process pixel samples for non-visible light from pixels allocated to detection of infrared light are disclosed.
1. A method comprising:
determining an interpolated pixel value based, at least in part, on a plurality of infrared pixel values;
reducing a correction value to the interpolated pixel value based, at least in part, on relative magnitudes of one or more clipped interpolated pixel values; and
applying a correction to the interpolated pixel value based, at least in part, on the reduced correction value.
2. The method of claim 1 , wherein the interpolated pixel value is unclipped.
3. The method of claim 1 , wherein applying the correction to the interpolated pixel value further comprises:
blurring a clipped interpolated clipped infrared pixel value; and
subtracting the reduced correction value from the blurred clipped interpolated infrared pixel value.
4. The method of claim 1 , wherein the interpolated pixel value is associated with an intensity in a red, blue or green color channel of a multi color channel imaging system.
5. The method of claim 1 , the method further comprising:
renormalizing at least some of the corrected pixel values according to a maximum output value of a multi color channel imaging device and amount of infrared correction in the interpolated pixel value.
6. The method of claim 5 , wherein renormalizing a corrected pixel value comprises approximating a ratio of the corrected pixel value to a normalization value using a Taylor series.
7. The method of claim 5 , wherein renormalizing a corrected pixel value comprises approximating a ratio of the corrected pixel value to a normalization value based, at least in part, on application of a plurality of multiplication circuits independent of any division circuits.
8. The method of claim 7 , wherein the plurality of multiplication circuits are adapted to operate in a floating point domain, and wherein at least one of the multiplication circuits implements a multiplication operation using a shift register.
9. The method of claim 1 , and further comprising:
determining an interpolated infrared pixel value based, at least in part, on raw pixel sample values obtained from a multi color channel imaging device and application of the correction value, the correction value being further computed based, at least in part, on raw pixel values in one or more color channels other than an infrared color channel according to a convolution of pixel values of one of the one or more color channels with a 3×3 kernel, the convolution comprising application of two filter coefficients reduced from three coefficients of the 3×3 kernel.
10. The method of claim 9 , wherein the two filter coefficients reduced from three coefficients of the 3×3 kernel are selected from first and second coefficients of the 3×3 kernel, and wherein a third coefficient of the 3×3 kernel is derived from a linear combination of the first and second coefficients of the 3×3 kernel.
11. The method of claim 9 , wherein the convolution further comprises application of a bandpass filter.
12. The method of claim 9 , wherein the raw pixel sample values are derived from a green channel of a multi color channel imaging device.
13. A device comprising:
circuitry to determine an interpolated pixel value based, at least in part, on a plurality of raw infrared pixel values;
circuitry to reduce a correction value to the interpolated pixel value based, at least in part, on relative magnitudes of one or more clipped interpolated pixel values; and
circuitry to apply a correction to the interpolated pixel value based, at least in part, on the reduced correction value.
14. The device of claim 13 , wherein the interpolated pixel value is unclipped.
15. An article comprising:
a non-transitory storage medium comprising computer-readable instructions stored thereon that are executable by one or more processors of a computing device to:
determine an interpolated pixel value based, at least in part, on a plurality of infrared pixel values;
reduce a correction value to the interpolated pixel value based, at least in part, on relative magnitudes of one or more clipped interpolated pixel values; and
apply a correction to the interpolated pixel value based, at least in part, on the reduced correction value.
16. The article of claim 15 , wherein the instructions are further executable by the one or more processors to:
blur a clipped interpolated infrared pixel value; and
subtract the reduced correction value from the blurred clipped interpolated infrared pixel value to at least in part apply the correction.
17. The article of claim 15 , wherein the interpolated pixel value is associated with an intensity in a red, blue or green color channel of a multi color channel imaging system.
18. An article comprising:
a non-transitory storage medium comprising computer-readable instructions stored thereon that are executable by one or more processors of a computing device to:
express a circuit, to be formed in a circuit device, to determine an interpolated pixel value based, at least in part, on a plurality of infrared pixel values;
express a circuit, to be formed in the circuit device, to reduce a correction value to the interpolated pixel value based, at least in part, on relative magnitudes of one or more clipped interpolated pixel values; and
express a circuit, to be formed in the circuit device, to apply a correction to the interpolated pixel value based, at least in part, on the reduced correction value.