KR100192787B1 - Apparatus and method of processing scramble-signal in a tv receiver - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal processing method and circuit for receiving a scrambled broadcast in a TV receiver, comprising: a tuner for tuning a channel of a broadcast signal received through an antenna; A TV receiver having an audio processing IC for processing a video signal among broadcast signals tuned from a tuner and an intermediate frequency amplified signal, the TV receiver comprising: detecting whether a scramble is applied to the tuned broadcast signal; If the scramble is applied to all audio signals, the first control signal to tune to another channel; if the scramble is applied to the audio signal; the second control signal to mute the audio signal; and if the scramble is applied to the video signal. Output from the scramble detector and the scramble detector for outputting a third control signal for It is composed of a microcomputer that controls the tuner, the audio processing IC, and an image processing IC according to the third control signal to the first. Therefore, when the scrambled broadcast signal is received, noise may be prevented from being input to the voice processing IC or the image processing IC.

Description

Signal Processing Method and Circuit in Receiving Scrambled Broadcast in TV Receiver

1 is a block diagram showing a signal processing circuit upon receiving scrambled broadcast in a TV receiver according to the present invention.

2 is a flowchart illustrating a signal processing method when receiving a scrambled broadcast in a TV receiver according to the present invention.

* Explanation of symbols for the main parts of the drawings

10: tuner 11: IF amplifier

12: Video / Audio Separator 13: Audio Processing IC

14: image processing IC 15: scramble detector

16: micom 17: indicator

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to TV receivers, and more particularly, to a signal processing method and circuit in receiving scrambled broadcasts.

Recently, as the technology of the broadcasting system is advanced, broadcasting programs have been diversified, such as teletext and still image broadcasting, high-definition television (HDTV) broadcasting, and digital signal broadcasting systems. CATV), commercial broadcasting by Japan's broadcasting satellite / communication satellite (BS / CS), and pay cable TV (PAY CATV) broadcasting by French terrestrial wave become practical and recent satellite communication broadcasting by BS / CS There is a paid broadcast available.

The Euro program provided by Euro Broadcasting is a program that only subscribers who have a contract with the program provider can receive. The subscriber pays the program provider a fee to watch the paid program. The paid program is scrambled from the broadcasting station and transmitted, since the program needs to be prevented from being viewed by the non-contractor, and the program is to be descrambled at the receiver of the contract subscriber.

That is, when a subscriber has a contract with a broadcasting station for a paid program, the subscriber informs the broadcasting station of the desired paid program, for example, by telephone, so that the broadcasting station can decode the subscriber's identification information and the scramble signal of the contract paid program. The key data is stored in the memory, and when the broadcasting of the contract pay program is started, the key data is transmitted from the broadcasting station to the receiver of the contract subscriber. At this time, the subscriber of the contract subscriber can descramble the contract paid program scrambled and transmitted using the received key data so that the subscriber can receive the paid program contracted by him.

There are two types of pay broadcasting, wired, terrestrial wireless and satellite direct reception. Among them, pay-cable and satellite master antenna TV (SMATV), and terrestrial wireless are HVN and LPTV (low power TV). There are STV (Subscription TV) and MDS (Multipoint Distribution Service), and there is TV Receive Only (TVRO).

The scramble method includes a scramble method for a video signal and a scramble method for an audio signal. The dual video signal scramble method has an amplitude processing method and a time base processing method, and the voice signal scramble method has a pseudo random signal overlapping method and an encryption method. There is this. In addition, the amplitude processing method includes a polarity inversion method, an interference wave superimposition method, a sine wave multiplication method, a square wave multiplication method, a synchronization signal cancellation method, and the like. Time-base compaction.

However, in a general TV receiver which is not provided with a scramble decoder, when a broadcast program having such a scramble is received, a large noise occurs in a video signal or an audio signal.

Therefore, an object of the present invention is to determine whether the scrambled to the broadcast program received through the antenna in the TV receiver when the scrambled for the audio signal mute the audio signal, if the scrambled for the video signal The present invention provides a signal processing method and circuit for receiving a scrambled broadcast for controlling to block an image signal.

In order to achieve the above object, a signal processing method for receiving a scrambled broadcast according to the present invention includes a tuner for tuning a channel of a broadcast signal received through an antenna and a voice for processing a voice signal among broadcast signals tuned from the tuner and intermediate-frequency amplified A TV receiver having a processing IC and an image processing IC for processing a video signal among broadcast signals tuned from a tuner and having an intermediate frequency amplification, comprising: a scramble detection step of detecting whether scramble is applied to the tuned broadcast signal; A channel switching step of switching channels by controlling the tuner when the scramble is applied to the detection result image and audio signal in the scramble detection step; A voice muting step of muting the voice signal by controlling the voice processing IC when the scramble is applied to the voice signal as a result of the detection in the scramble detection step; And an image blocking step of controlling the image processing IC to block the image signal when the scramble is applied to the detection result of the detection in the scramble detection step.

In order to achieve the above object, the signal processing circuit in the scrambled broadcast reception according to the present invention is a tuner for tuning a channel of a broadcast signal received through an antenna, and a voice for processing a voice signal among broadcast signals tuned from the tuner. A TV receiver comprising a processing IC and an image processing IC for processing a video signal among broadcast signals tuned from a tuner and having an intermediate frequency amplification, wherein the TV receiver detects whether or not scramble is applied to the tuned broadcast signal to detect a video signal and audio. If the scramble is applied to all signals, the first control signal for tuning to another channel; if the scramble is applied to the audio signal, the second control signal for mutating the audio signal and the scramble is applied to the video signal. In this case, the scramble detection for outputting the third control signal for blocking the video signal .; And a micom for controlling the tuner, the voice processing IC, and the image processing IC according to the first to third control signals output from the scramble detector.

Hereinafter, with reference to the accompanying drawings will be described in detail an embodiment of the present invention.

1 is a block diagram showing a scrambled broadcast reception signal processing circuit in a TV receiver according to the present invention, and includes a tuner 10, an IF amplifier 11, a video / audio separator 12, and an audio processing IC 13; And an image processing IC 14 for processing the video signal among the broadcast signals tuned to the intermediate frequency by the tuner, and detecting whether or not scramble is applied to the tuned broadcast signal, so that the first control signal, the second control signal, The tuner 10, the audio processing IC 13, and the image processing IC 14 are controlled according to the scramble detector 15 for outputting the third control signal and the first to third control signals output from the scramble detector 15. And a display 17 for indicating whether or not to be scrambled to the outside.

2 is a flowchart illustrating a signal processing method when receiving a scrambled broadcast signal in a TV receiver according to the present invention, detecting whether a scramble is applied to a tuned broadcast signal (step 21), and video and audio signals. Switching the channel when the scramble spans (steps 22 and 23), muting the audio signal when the scramble spans the voice signal (steps 24 and 25), and scrambles the video signal. In this case, the video signal is blocked (steps 26 and 27).

Referring to FIG. 1 and FIG. 2, the operation of the present invention will be described.

The tuner 10 is tuned to the channel of the broadcast signal received through the antenna according to the user's selection and supplied to the IF amplifier 11, the IF amplifier 11 is an intermediate frequency amplified tuned broadcast signal to the video / audio separator And the video / audio separator 12 separates the video signal and the audio signal from the intermediate frequency signal and supplies them to the audio processing IC 13 and the image processing IC 14, respectively.

The audio processing IC 13 performs an operation such as image detection, audio intermediate frequency amplification, and frequency modulation and demodulation on the audio signal output from the video / audio separator 13, and amplifies and outputs the audio signal to the speaker SP. The IC 14 performs an operation such as image detection, image amplification, and chroma processing on the image signal output from the image / audio separator 13, and then amplifies and outputs the image signal to the CRT.

The scramble detector 15 detects whether the scramble is applied to the intermediate frequency signal output from the IF amplifier 11 (step 21 in FIG. 2), and if the scramble is applied to both the video signal and the audio signal, The first control signal for tuning the channel is supplied to the microcomputer 16, and if the scramble is applied to the audio signal, the third control signal for muting the audio signal is supplied to the microcomputer 16, and the video signal is supplied to the video signal. When the scramble spans, the third control signal for blocking the video signal is supplied to the microcomputer 16.

The microcomputer 16 is a TV receiver in which various video control (luminance / contrast) and audio control (volume / balance control), channel selection, A first output from the scramble detector 15 to perform functions such as picture-in-picture board control, power on / off, voice mode selection, A / V switching, and on screen display (OSD). The tuner 11, the audio processing IC 14, and the image processing IC 15 are controlled according to the third to third control signals. That is, when the first control signal is applied (step 22), the tuner 11 is controlled to switch to another channel (step 23), and when the second control signal is applied (step 24), the voice processing IC 14 ), The audio signal is muted (step 25), and when the third control signal is applied (step 26), the image processing IC 15 is controlled to block the input video signal (step 27). .

When the first to third control signals are applied to the microcomputer 16, the display unit 17 displays the corresponding information, that is, video / audio scramble, voice scramble, and video scramble information to the outside so that the user recognizes the information.

As described above, in a TV receiver having a muting function when receiving scrambled broadcasts according to the present invention, if a scramble is applied to a broadcast program received through an antenna, the TV receiver mutes the voice signal. When the scrambled video signal is scrambled, the image signal is blocked to prevent noise from being input to the audio processing IC or the image processing IC when the scrambled broadcast signal is received.

Claims (3)

A TV receiver having a tuner for tuning a channel of a broadcast signal received through an antenna, and a voice processing IC for processing a voice signal among broadcast signals tuned from the tuner and having an intermediate frequency amplification, wherein the scramble is performed on the tuned broadcast signal. Scramble detection step to detect whether or not hanging; A channel switching step of switching channels by controlling the tuner when the scramble is applied to the detection result image and audio signal in the scramble detection step; A voice muting step of muting the voice signal by controlling the voice processing IC when the scramble is applied to the voice signal as a result of the detection in the scramble detection step; And a video blocking step of controlling the video processing IC to block the video signal when the detection result of the detection in the scramble detection step blocks the video signal. Treatment method. A tuner that tunes a channel of a broadcast signal received through an antenna, a voice processing IC that processes an audio signal among broadcast signals tuned from the tuner and an intermediate frequency amplified signal, and a video signal among broadcast signals tuned from the tuner and intermediate frequency amplified A TV receiver having an image processing IC, comprising: detecting whether or not scramble is applied to the selected broadcast signal, and when the scramble is applied to both the video signal and the audio signal, first control for tuning another channel. A scramble detector for outputting a second control signal for muting the audio signal when the scramble is applied to the signal and the audio signal, and a third control signal for blocking the video signal when the scramble is applied to the video signal; And a microcomputer for controlling the tuner, the voice processing IC, and the image processing IC according to the first to third control signals output from the scramble detector. . 3. The signal processing circuit of claim 2, further comprising an indicator for externally displaying corresponding information when the first to third control signals are applied to the micom.