In-vehicle system and signal processing method

An in-vehicle system to be added to a vehicle provided with a basic system, the in-vehicle system comprising:

• a memory;
• and
• a processor that executes processing in cooperation with the basic system using the memory,
• wherein (i) in a first mode in which transmission and reception of a video signal and an audio signal are not performed between the basic system and the in-vehicle system, the processor does not transmit any signal to the basic system, receives a signal transmitted from the basic system to the in-vehicle system, and executes the processing, and
• (ii) in a second mode in which one or more lines of video audio signals each including at least one of a video signal or an audio signal are transmitted and received between the basic system and the in-vehicle system, the processor does not transmit the one or more lines of video audio signals to the basic system, receives the one or more lines of video audio signals transmitted from the basic system to the in-vehicle system, and executes the processing.

A signal processing method to be performed by an in-vehicle system,

• the in-vehicle system including a first system provided in a vehicle, and a second system to be added to the vehicle,
• the signal processing method comprising:
• when the first system and the second system execute processing in cooperation,
• (i) in a first mode in which transmission and reception of a video signal and an audio signal are not performed between the first system and the second system, transmitting a signal only unidirectionally from the first system to the second system;
• and
• (ii) in a second mode in which one or more lines of video audio signals each including at least one of a video signal or an audio signal are transmitted and received between the first system and the second system, transmitting the one or more lines of video audio signals only unidirectionally from the first system to the second system.