A method, apparatus, and computer readable medium controlling a servo of a recording and/or reproducing apparatus, using a detected header field signal. An optical recording and/or reproducing apparatus includes a playback signal detector that detects a playback signal and a track error signal from information recorded on a DVD-RAM disc, as picked up by a pickup. A header field signal detecting circuit detects a header field signal by comparing a sampled playback signal for a signal representing the presence of a header field with a reference level and holding the comparison result for a predetermined period of time to generate the header field signal. Accordingly, a tracking servo can be stably controlled by using a tracking driving signal that is not affected by the presence of a header. Also, in a seek mode, the track error signal can be held based on the header field signal to generate a track count signal that is similarly not affected by the header. As a result, the number of tracks on the DVD-RAM disc can be accurately counted by using the track error signal.