Hitachi, Ltd.

Nobuaki Naoi

Katunobu Takeda

Ikuo Yuki

Fumio Miyazawa

When channel setup is carried out under poor receiving condition, the previous channel information that has been stored on a channel map in the channel setup carried out under normal receiving condition is replaced with the later channel information that is stored on the channel map including less acquired channel information formed in the channel setup carried out later. Existence of broadcast signal is judged only on channels other than channels that are registered based on the fact that the channels include a broadcast signal on a channel map stored in the previous channel setup, and the channel information of the broadcast signal detected later is registered additionally on the channel map in a flash memory as the channel including the broadcast signal.

Receiver having a function to tune and set a channel and channel setup method

A noise reduction circuit comprising: a high-pass filter for extracting the high-frequency component of an image signal; a coring circuit for extracting a faint signal component included in the extracted high-frequency component as noise; a low-pass filter for extracting the low-frequency component of the image signal; an adder for adding the cored high-frequency component and the low-frequency component extracted by the low-pass filter; and a coring control circuit which detects the level of a luminance signal and controls the coring range of the coring circuit according to the level of the luminance signal. Since noise is visually more conspicuous in a dark portion of a picture than in a bright portion of a picture, the coring control circuit increases the coring range when the level of the luminance signal is low, namely, for a dark portion of a picture, and decreases the coring range when the level of the luminance signal is high, namely, for a bright portion of a picture to make noise indistinct over the entire area of a picture plane.

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Yokohama, Japan

Nobuaki Naoi