an eighth step which computes the time ratio, a second time ratio between the input timing of the first speed detection signal after the previous reproducing control signal is inputted with respect to the input timing of the previous reproducing control signal, and the number of the speed detection signals from the first speed detection signal after {HEAD ~ the previous reproducing control signal} to {TAIL ~ the first speed detection signal} after the current reproducing control signal and computes the number of the speed detection signal inputted thereto during one cycle of the reproducing control signal 
to
an eighth step which computes the time ratio , a second time ratio between the input timing of the first speed detection signal after the previous reproducing control signal is inputted with respect to the input timing of the previous reproducing control signal , and the number of the speed detection signals from the first speed detection signal after { HEAD ~ the previous reproducing control signal } to { TAIL ~ the first speed detection signal } after the current reproducing control signal and computes the number of the speed detection signal inputted thereto during one cycle of the reproducing control signal
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH