Method of digitally processing a plurality of pixels and temperature measurement apparatus

1 . A method of digitally estimating an intensity value associated with an electrical signal generated by a pixel of an array of sensing pixels of an optical sensor device, the method comprising:

(a) identifying a measurement pixel of a plurality of pixels corresponding to a measurement point on a target to be measured;

(b) identifying a first number of pixels corresponding to a line of pixels passing through the measurement pixel;

(c) identifying a second number of pixels of the first number of pixels either side of the measurement pixel, the second number of pixels having a number of intensity values, respectively;

(d) fitting a curve to the number of respective intensity values of the second number of pixels and respective linear locations of the second number of pixels along the line of pixels passing through the measurement pixel; and

(e) obtaining an estimated intensity value by referencing a relationship defined by the curve in respect of the measurement pixel, thereby simulating a predetermined field of view in respect of the measurement pixel narrower than an actual field of view of the measurement pixel.

2 . The method according to claim 1 , wherein the curve is fitted with respect to distances of the second number of pixels from the measurement pixel.

3 . The method according to claim 2 , wherein the distances of the second number of pixels from the measurement pixel comprises a first distance and a second distance, the first distance comprising an intra-pixel distance and the second distance comprises an inter-cluster distance, the intra-pixel distance being different from the inter-cluster distance.

4 . The method according to claim 1 , wherein the second number of pixels is located within a row of the array of pixels comprising the measurement pixel.

5 . The method according to claim 4 , further comprising:

identifying a third number of pixels of the first number of pixels, the third number of pixels having another number of intensity values, respectively;

fitting another curve to the third number of pixels using the another number of respective intensity values; and

determining another estimated intensity value from the another curve in respect of the measurement pixel.

6 . The method according to claim 5 , wherein the third number of pixels is located in a column of the array of pixels comprising the measurement pixel or a diagonal line in the array of pixels comprising the measurement pixel.

7 . The method according to claim 5 , further comprising:

using the estimated intensity value and the another estimated intensity value to determine a further estimated intensity value in respect of the measurement pixel.

8 . The method according to claim 1 , further comprising:

fitting the curve using a polynomial best fit algorithm or a bilinear interpolation algorithm.

9 . The method according to claim 1 , wherein identifying the measurement pixel further comprises:

searching the array of pixels in groups of pixels of a predetermined size in order to identify a block comprising a pixel having a highest intensity.

10 . The method according to claim 9 , wherein the groups of pixels of the predetermined size constitute a tessellation of a predetermined shape.

11 . The method according to claim 9 , wherein the groups of pixels constitute windows of pixels.

12 . The method according to claim 1 , further comprising:

identifying the measurement pixel by estimating an intensity value for a number of groups of pixels of the array of pixels, thereby yielding a plurality of estimated intensity values.

13 . The method according to claim 12 , further comprising:

selecting a highest value amongst the plurality of estimated intensity values as the measurement pixel.

14 . The method according to claim 1 , the method further comprising:

performing an alignment operation with respect to the target to be measured in order to identify the measurement pixel of the plurality of pixels corresponding to the measurement point on the target to be measured.

15 . A temperature measurement apparatus comprising:

a plurality of sensor pixels configured to capture a thermal image; and

a processing signal circuit configured to:

identify, after capture of the thermal image, a measurement pixel of the plurality of sensor pixels corresponding to a measurement point on a target to be measured;

identify, after the identification of the measurement pixel, a first number of pixels corresponding to a line of pixels passing through the measurement pixel;

identify, after the identification of the first number of pixels, a second number of pixels of the first number of pixels either side of the measurement pixel, the second number of pixels having a number of intensity values, respectively;

fit, after the identification of the second number of pixels, a curve to the number of respective intensity values of the second number of pixels and respective linear locations of the second number of pixels along the line of pixels passing through the measurement pixel; and

obtain, after the fitting of the curve, an estimated intensity value by referencing a relationship defined by the curve in respect of the measurement pixel, thereby simulating a predetermined field of view in respect of the measurement pixel narrower than an actual field of view of the measurement pixel.