Patent ID: 8405776

Claim:
A state detector of a video device, comprising: a first chroma detector, operating in a first state among a plurality of states, for processing an input signal and generating an output signal; a second chroma detector, operating in the first state among the states, for detecting whether the input signal is processed normally; and a controller, coupled to the first chroma detector and the second chroma detector, wherein when the second aroma detector is not capable of processing the input signal normally, the controller controls the second chroma detector to switch between the states until the second chroma detector operates in a second state to process the input signal normally, and the controller sets the first chroma detector to operating in the second state, wherein the second chroma detector comprises a phase detector, the phase detector is configured to detect whether a phase of the input signal can be locked to output a first signal, and the controller determines whether the second chroma detector is capable of processing the input signal normally according to the first signal.