Patent ID: 7746745

Claim:
A method for determining a type of a digital versatile disc (DVD), comprising: receiving a general wobble signal, wherein the general wobble signal comprises at least a wobble signal and other signals on the DVD that are read with the wobble signal; finding a peak-to-peak voltage from the general wobble signal; determining the type of the DVD according to the peak-to-peak voltage from the general wobble signal, comprising: indicating the DVD as a DVD− if the peak-to-peak voltage from the general wobble signal is greater than a first predetermined threshold; indicating the DVD as a DVD-ROM if the peak-to-peak voltage from the general wobble signal is less than a second predetermined threshold; and indicating the DVD as a DVD+ if the peak-to-peak voltage from the general wobble signal is less than or equal to the first predetermined threshold and is greater than or equal to the second predetermined threshold, wherein the first predetermined threshold is greater than the second predetermined threshold; and adjusting a magnitude of the wobble signal or a magnitude of the general wobble signal to be at least approximately equal to a predetermined standard voltage.