CN1602072A

CN1602072A - Macrovision declarifier for high resolution TV signal receiver

Info

Publication number: CN1602072A
Application number: CN 03135897
Authority: CN
Inventors: 田朝勇; 马铁桥
Original assignee: Sichuan Changhong Electric Co Ltd
Current assignee: Sichuan Changhong Electric Co Ltd
Priority date: 2003-09-25
Filing date: 2003-09-25
Publication date: 2005-03-30

Abstract

The invention relates to circuit device for high clearness TV set to descramble synchronized signal of 480i, 480P, 1080i, 720P etc. signals scrambled by Macrovision. Overcoming disadvantages of prior art, the invention provides descrambler and easy to implement for high clearness TV set to eliminate scrambling added by Macrovision.

Description

A kind of HDTV signal receiver withimaginary-sample-presencedetector Macrovision removes scrambling apparatus

Technical field

The Macrovision that the present invention relates to a kind of HDTV signal receiver withimaginary-sample-presencedetector removes scrambling apparatus, specifically just relate to a kind of be used for HDTV signal receiver withimaginary-sample-presencedetector can be to removing the circuit arrangement of scrambling through 480i, the 480P of Macrovision scrambling, the synchronizing signal of signals such as 1080i, 720P.

Background technology

Macrovision is the general designation of Macrovision company invention and numerous anti-copy technology of applying for a patent, and its basic anti-copy method is to reach the purpose that the information source property right is protected by making video recording apparatus can not obtain stable vision signal.The standard anti-copy technology that present consumer video tape recorder, DVD etc. are taked is by insert 4 unnecessary disturbing pulses respectively after 8 horizontal synchronizing pulses of the head after the vision signal field synchronization, thereby make video recording apparatus because of these 4 " row synchronously " pulses faster can not accurately lock video signal flow, reach thus and prevent the purpose that illegally copies.In the analog video decoder device, generally comprise Macrovision and removed scrambling circuit, with filtering scrambling pulse, but in the HDTV receiver, signals such as the 480i of scrambling, 480P, 1080i, 720P are direct input digit presentation managers behind AD converter (non-video decoder) and sync separator in this way, presentation manager requires the synchronizing signal of input must not have any scrambling pulse, otherwise, make it stably to catch image with the phase-locked loop circuit and the synchronous decoding circuit of jamming pattern processor.Therefore the synchronizing signal of input imagery processor must go scrambling to handle through Macrovision earlier in the Digital Television.Two kinds of solutions are generally arranged at present: the one, adopt special phase-locked loop sync separator, the phase-locked loop circuit of this sync separator is not followed the tracks of frequency input signal in the certain hour before and after field synchronization, and be in the inertial oscillation state, thereby the Macrovision scrambling pulse that may exist in removing during this period of time; The 2nd, between sync separator and presentation manager, insert the pulse low-pass filter circuit, to remove the Macrovision scrambling pulse of high frequency.But the inertial oscillation of phase-locked loop circuit can not guarantee to go accurately synchronizing frequency and phase place in the scheme one, and it is still unstable to make that every field pattern resembles in the incipient several rows; The pulse low pass filter that scheme two is adopted at different signals such as 480i, 480P, 1080i, 720P, needs to set different time constants, thereby implements comparatively complicated.

Summary of the invention

In the deficiency that overcomes present technology, provide a kind of circuit succinct when the present invention is per, the low a kind of HDTV signal receiver withimaginary-sample-presencedetector Macrovision easy to implement of cost removes scrambling apparatus.

Content of the present invention is: a kind of HDTV signal receiver withimaginary-sample-presencedetector Macrovision removes scrambling apparatus, it is characterized in that described input signal one tunnel send A/D converter, and Bie Yilu send sync separator; A/D converter becomes the analog signal of input digital signal and exports presentation manager to, sync separator separates trip, field system chronizing impulse from input signal, the direct input imagery processor of field system chronizing impulse V wherein, and to the input signal through the Macrovision scrambling, the horizontal synchronizing pulse Hm of sync separator output has comprised the scrambling pulse, in order to obtain stable image, must handle through going scrambling before the Hm input imagery processor.

Feature of the present invention is:

1, can carry out Macrovision to the various high-definition signals that comprise 480P, 1080i, 720P goes scrambling to handle.

2, various signals, Macrovision go scrambling apparatus only to need the one-level circuit, one group of design parameter.

3, the working method of flip flop design for can not heavily triggering.

4, the trigger transient state operating time is set to the maximum scrambling pulse period greater than Macrovision, less than the signal minimum row cycle.

Description of drawings

Fig. 1 is that the present invention uses block diagram at the digital tv image processor.

Fig. 2 is a monostable flipflop structural representation of the present invention.

Execution mode

As shown in Figure 1 and Figure 2, a kind of HDTV signal receiver withimaginary-sample-presencedetector Macrovision removes scrambling apparatus, it is characterized in that described input signal one tunnel send A/D converter, and Bie Yilu send sync separator; A/D converter becomes the analog signal of input digital signal and exports presentation manager to, sync separator separates trip, field system chronizing impulse from input signal, the direct input imagery processor of field system chronizing impulse V wherein, and to the input signal through the Macrovision scrambling, the horizontal synchronizing pulse Hm of sync separator output has comprised the scrambling pulse, in order to obtain stable image, must handle through going scrambling before the Hm input imagery processor.

Oscillography shape figure has drawn and has had the part horizontal synchronizing pulse of Macrovision scrambling pulse, and wherein

pulse

1,2,3,4 is horizontal synchronizing pulse, and the high-frequency impulse between the

pulse

2,3 is Macrovision scrambling pulse.Because being trailing edge, flip flop design triggers, so in the t1 moment of pulse 1, trigger anode output high level, behind time T=0.7Rt * Ct, before pulse 2 arrives, the trigger anode is got back to low level state, and the triggering level control end also becomes low level and makes trigger get back to the normal condition that can be triggered; In the t2 moment of pulse 2, trigger is triggered once more, its anode is exported high level again, and because at Macrovision scrambling impulse duration, the triggering level control end of trigger remains high level, thereby forbid that trigger is triggered again, thereby the trailing edge of Macrovision scrambling pulse can not produce triggering (being that trigger can not heavily trigger); Up to t3 constantly, trigger triggering level control end is got back to low level again, and in the t4 moment of pulse 3, trigger just can be triggered again again.Like this, after the output of trigger negative terminal was carried out " logical AND " with Macrovision scrambling horizontal synchronizing pulse, horizontal synchronizing

pulse

1,2,3 was just separated, and Macrovision scrambling pulse then conductively-closed has been fallen.

Claims

1, a kind of HDTV signal receiver withimaginary-sample-presencedetector Macrovision removes scrambling apparatus, it is characterized in that described input signal one tunnel send A/D converter, and Bie Yilu send sync separator; A/D converter becomes the analog signal of input digital signal and exports presentation manager to, sync separator separates trip, field system chronizing impulse from input signal, the direct input imagery processor of field system chronizing impulse V wherein, and to the input signal through the Macrovision scrambling, the horizontal synchronizing pulse Hm of sync separator output has comprised the scrambling pulse, in order to obtain stable image, must handle through going scrambling before the Hm input imagery processor.