An image sensor, comprising: a filter array, comprising a plurality of first sets of filters and a plurality of second sets of filters, each of the plurality of first sets of filters comprising a plurality of first color filters and a plurality of second color filters, a number of first color filters and a number of second color filters being same in each of the plurality of first sets of filters, and each of the plurality of second sets of filters comprising a plurality of first color filters and a plurality of third color filters, a number of first color filters and a number of third color filters being same in each of the plurality of second sets of filters; and a pixel array, comprising a plurality of pixels each corresponding to one filter in the filter array and configured to receive light passing through the corresponding filter to generate an electrical signal, wherein the image sensor is configured to combine, for each of the plurality of first sets of filters, electrical signals generated by the pixels corresponding to first color filters in the first set of filters and electrical signals generated by pixels corresponding to second color filters in the first sets of filters to generate a first pixel signal and a third pixel signal respectively, the first pixel signal representing a value in a first color channel of the light applied to the pixels corresponding to the first set of filters, and the third pixel signal representing a value in a second color channel of the light applied to the pixels corresponding to the first set of filters, and the image sensor is configured to combine, for each of the plurality of second sets of filters, electrical signals generated by the pixels corresponding to first color filters in the second set of filters and electrical signals generated by pixels corresponding to third color filters in the second sets of filters to generate a second pixel signal and a fourth pixel signal respectively, the second pixel signal representing a value in the first color channel of the light applied to the pixels corresponding to the second set of filters, and the fourth pixel signal representing a value in a third color channel of the light applied to the pixels corresponding to the second set of filters, wherein the number of filters in each of the plurality of first sets of filters is N*N, and the number of filters in each of the plurality of second sets of filters is N*N, where N is an integer greater than 2. a filter array, comprising a plurality of first sets of filters and a plurality of second sets of filters, each of the plurality of first sets of filters comprising a plurality of first color filters and a plurality of second color filters, a number of first color filters and a number of second color filters being same in each of the plurality of first sets of filters, and each of the plurality of second sets of filters comprising a plurality of first color filters and a plurality of third color filters, a number of first color filters and a number of third color filters being same in each of the plurality of second sets of filters; and a pixel array, comprising a plurality of pixels each corresponding to one filter in the filter array and configured to receive light passing through the corresponding filter to generate an electrical signal, wherein the image sensor is configured to combine, for each of the plurality of first sets of filters, electrical signals generated by the pixels corresponding to first color filters in the first set of filters and electrical signals generated by pixels corresponding to second color filters in the first sets of filters to generate a first pixel signal and a third pixel signal respectively, the first pixel signal representing a value in a first color channel of the light applied to the pixels corresponding to the first set of filters, and the third pixel signal representing a value in a second color channel of the light applied to the pixels corresponding to the first set of filters, and the image sensor is configured to combine, for each of the plurality of second sets of filters, electrical signals generated by the pixels corresponding to first color filters in the second set of filters and electrical signals generated by pixels corresponding to third color filters in the second sets of filters to generate a second pixel signal and a fourth pixel signal respectively, the second pixel signal representing a value in the first color channel of the light applied to the pixels corresponding to the second set of filters, and the fourth pixel signal representing a value in a third color channel of the light applied to the pixels corresponding to the second set of filters, wherein the number of filters in each of the plurality of first sets of filters is N*N, and the number of filters in each of the plurality of second sets of filters is N*N, where N is an integer greater than 2.