A method of detecting motion of a moving object and transmitting an image of the moving object, the method at least comprising: capturing an image sequence of the moving object comprising a plurality of frames separated from each other by a predetermined period of time; taking a first frame (k) and a second frame (k + 1) from the plurality of frames and detecting whether there is motion in the captured image sequence by: calculating a first two-parameter statistical error between the first frame (k) and the second frame (k + 1); and determining whether the first two-parameter statistical error is greater than a first predetermined threshold value; if motion is not detected, replacing the first frame by the second frame and the second frame by the next frame in the captured image sequence and detecting whether there is motion in the captured image sequence by comparing the next frame to the second frame in the same manner; characterized by: whereas if motion is detected, extracting a moving part from the captured image sequence by: dividing each of the first and second frames into corresponding arrays of windows and calculating a second two-parameter statistical error between each of the windows in the first frame (k) and a corresponding one of the windows in the second frame (k + 1); selecting (7, 8) a subset of the windows having the highest value or values of the second two-parameter statistical error between the first and second frames as the moving part; supplementing the subset of windows selected as the moving part with one or more other windows from the first and second frames which together with the selected windows constitute a complete rectangle of windows; and transmitting the complete rectangle of windows by transmitting the other windows together with the selected windows. capturing an image sequence of the moving object comprising a plurality of frames separated from each other by a predetermined period of time; taking a first frame (k) and a second frame (k + 1) from the plurality of frames and detecting whether there is motion in the captured image sequence by: calculating a first two-parameter statistical error between the first frame (k) and the second frame (k + 1); and determining whether the first two-parameter statistical error is greater than a first predetermined threshold value; calculating a first two-parameter statistical error between the first frame (k) and the second frame (k + 1); and determining whether the first two-parameter statistical error is greater than a first predetermined threshold value; if motion is not detected, replacing the first frame by the second frame and the second frame by the next frame in the captured image sequence and detecting whether there is motion in the captured image sequence by comparing the next frame to the second frame in the same manner; whereas if motion is detected, extracting a moving part from the captured image sequence by: dividing each of the first and second frames into corresponding arrays of windows and calculating a second two-parameter statistical error between each of the windows in the first frame (k) and a corresponding one of the windows in the second frame (k + 1); selecting (7, 8) a subset of the windows having the highest value or values of the second two-parameter statistical error between the first and second frames as the moving part; dividing each of the first and second frames into corresponding arrays of windows and calculating a second two-parameter statistical error between each of the windows in the first frame (k) and a corresponding one of the windows in the second frame (k + 1); selecting (7, 8) a subset of the windows having the highest value or values of the second two-parameter statistical error between the first and second frames as the moving part; supplementing the subset of windows selected as the moving part with one or more other windows from the first and second frames which together with the selected windows constitute a complete rectangle of windows; and transmitting the complete rectangle of windows by transmitting the other windows together with the selected windows.