A DVD navigator based on a vehicle-mounted terminal is disclosed. The DVD navigator includes: a menu panel module, configured to generate a first level in response to reception of an unload instruction; and a quick-unload module, configured to acquire the first level in a sleep state of the DVD navigator and process the first level to generate a second level and a pulse signal so as to control the DVD navigator to quickly unload a disc according to the second level in the sleep state. By the aforesaid way, the present disclosure can effectively reduce the unload time of the DVD navigator by controlling the DVD navigator to quickly unload a disc in the sleep state after receiving the unload instruction.

At least a portion of a first servo mark is read using a first read head during a rotation of a disk, the rotation comprising no more than 360 degrees. At least a portion of a second servo mark is read using a second read head during the rotation of the disk. Tracking positions of the first read head and the second read head are determined during the rotation based on reading the first servo mark and the second servo mark.