Electronic device, comprising: a first array of image pixels (Pix) having inputs coupled to first selection tracks and outputs coupled to first output tracks; at least one second array of test pixels (Tst) having inputs coupled to second selection tracks and outputs coupled to the first output tracks; at least one third array of test pixels (Tst) having inputs coupled to the first selection tracks and outputs coupled to second output tracks; and a processor, wherein each test pixel of the second and third arrays is configured to supply the processor with an output signal at one or the other of two expected values in the absence of a defect in one of the first selection tracks or in one of the first output tracks, and wherein the processor is configured to determine a defect on delivery of the output signal at another value than one or the other of the two expected values, by one or a plurality of the test pixels, wherein the image pixels (Pix) of the first array are configured to deliver video signals on acquisition of an image, wherein the second array and/or the third array comprises at least one assembly of test pixels (Tst) comprising a first alignment of test pixels configured to deliver output signals, each at one or the other of two expected values in the absence of a defect, wherein the processor is configured to successively receive a succession of output signals of the first alignment read with video signals of image pixels (Pix) of the first array, to determine, from the successive reading of any portion, comprising at least a given number of the successively-read output signals of the first alignment, whether the orientation of the acquired image is correct, and/or to which position of the first array of image pixels (Pix) correspond the video signals read with the output signals of said portion, wherein the test pixels of the first alignment are distributed in successive groups of test pixels, each group comprising a first set of test pixels, and a second set of test pixels, the test pixels of the first set of each group being configured to deliver a first pattern, and at least a portion of the test pixels of the second set of each group being configured to deliver a second pattern identifying said group. a first array of image pixels (Pix) having inputs coupled to first selection tracks and outputs coupled to first output tracks; at least one second array of test pixels (Tst) having inputs coupled to second selection tracks and outputs coupled to the first output tracks; at least one third array of test pixels (Tst) having inputs coupled to the first selection tracks and outputs coupled to second output tracks; and a processor, wherein each test pixel of the second and third arrays is configured to supply the processor with an output signal at one or the other of two expected values in the absence of a defect in one of the first selection tracks or in one of the first output tracks, and wherein the processor is configured to determine a defect on delivery of the output signal at another value than one or the other of the two expected values, by one or a plurality of the test pixels, wherein the image pixels (Pix) of the first array are configured to deliver video signals on acquisition of an image, wherein the second array and/or the third array comprises at least one assembly of test pixels (Tst) comprising a first alignment of test pixels configured to deliver output signals, each at one or the other of two expected values in the absence of a defect, wherein the processor is configured to successively receive a succession of output signals of the first alignment read with video signals of image pixels (Pix) of the first array, to determine, from the successive reading of any portion, comprising at least a given number of the successively-read output signals of the first alignment, whether the orientation of the acquired image is correct, and/or to which position of the first array of image pixels (Pix) correspond the video signals read with the output signals of said portion, wherein the test pixels of the first alignment are distributed in successive groups of test pixels, each group comprising a first set of test pixels, and a second set of test pixels, the test pixels of the first set of each group being configured to deliver a first pattern, and at least a portion of the test pixels of the second set of each group being configured to deliver a second pattern identifying said group.