Spatial Switching is based on three ideas: The first idea of this technique is to avoid, as more as possible, some transition patterns. Indeed, we have measured the consumption of all the possible transition patterns and we have seen that the energy consumption can vary up to 20 times. The second idea is to optimize, as a priority, the transition patterns which have the biggest appearance ratio. Indeed, optimize a transition pattern which appears rarely is ridiculous. The last idea is to apply only the codec on the wires that have the most important activity. In signal and image processing applications, it is the least significant bits that have the most activity; so it is not necessary to apply codec on MSB since their activity is low. Furthermore, if we do not apply the codec on MSB, we increase the consumption gain since the codec is smaller (the consumption due to the codec is proportional to its size).