The invention relates to a method for reading a two-dimensional matrix of pixels of an image sensor, the matrix being organized in blocks of pixels forming macropixels, each macropixel being readable independently of one another in high resolution mode and/or in low resolution mode. The method includes the steps of, during the selection of the high resolution readout mode for a macropixel, in reading and storing the values of the pixels thereof, in order to define a reference macropixel, and during the subsequent high resolution readout cycles of this macropixel, in forming the difference between the read values of the pixels thereof and the values of the corresponding pixels of the reference macropixel.