MXPA00005997A - Program signal blocking system - Google Patents

Abstract

An apparatus and a method for preventing a user from bypassing a viewer blocking system using program related information, such as content ratings, included in a program signal. The present invention prevents the user from exploiting the time delay associated with detecting, decoding and comparing the program related information by switching channels to observe portions of objectionable programs before the blocking system can react. The present system comprises a processor (110) which controls the output of a selected program signal (VIDEO, VIDEO IN, AUDIO IN) in response to a determination of whether an associated program related information meets a user selected blocking criteria. The processor blocks display of a program signal when a predetermined sequence of signal channel selections is detected and then continues to block the display of the program signal at least until the determination is performed. The predetermined sequence of signal channel selections may comprise continual re-tuning of the same channel and/or switching between two channels. The present method comprises detecting a particular sequence of signal channel selections and blocking the display of the program signal upon detecting the predetermined sequence. If the predetermined sequence of signal channel selections is detected the display blocking is maintained at least until a program related information associated with the program signal is detected and a determination of the satisfaction of a user selected blocking criteria is performed.

Description

PROGRAM SIGNAL LOCK SYSTEM The present invention relates to a system for processing and producing a program signal, such as a television or radio program signal, or more particularly with a system for processing and producing a program signal according to auxiliary information included with the program signal. In addition to the portions of video and / or audio programs of a particular television or radio program, the program signals may include auxiliary information. The program and auxiliary information may comprise analog and / or digital signals. An analog signal, such as a standard NTSC television signal, may include auxiliary data during the horizontal line intervals within the vertical blanking interval (VBI). For example, the titration data is included in line 21, field 1 of the vertical blanking interval and extended data services information (XDS) are included in line 21, field 2 of the vertical blanking interval. In digital systems, video signals are usually transmitted in packets, or groups, or data words. Each packet includes identification information and represents a particular type of information, such as video, audio or auxiliary information. An example of a digital television system that processes a digital television signal in a packet is the digital satellite system receiver (DSS®) manufactured by Thomson Consumer Electronics, Inc., of Indianapolis, Indiana. An auxiliary information application is related to the technology called "V-chip" that allows users to automatically block objectionable material from their television receivers. In systems that use this technology, the information related to the program included with the program signals provides advisory information about the respective programs. The consultative information of programs can take several forms; including, but not limited to, ratings of programs that indicate the recommended age for the observer and / or content ratings that indicate the presence and / or level of objectionable material, such as sex, violence, language, etc., in the program. For example, a proposed program rating system is described and proposed in the EIA-744 specification entitled "Transport of Content Advisory Information using Extended Data Service (XDS)". The V-chip technology examines the advisory information of the program associated with each selected program signal against a blocking criterion selected by the user, such as a selected blocking level of qualification, and blocks the signal of the program if the advisory information of the program satisfies the blocking criteria selected by the user. For example, if the blocking level is set to "PG", all programs that have a "PG" rating and higher, such as "R", "NC-17" and "X", will be blocked. Blocking the program signal refers to preventing the user from accessing an objectionable program by, for example, rendering the video black or otherwise indecipherable, muting the audio and disabling the display of subtitling related to the program. When the advisory information indicates that the objectionable material is no longer being received, the V-chip system unlocks the program channel by displaying the video, unmute the audio and / or enabling the display of the subtitle related to the program. One difficulty associated with the V-chip technology described above is the delay time required for a television receiver to receive and decode information related to the program, included with the program signal. Since information related to a program is transmitted periodically, between video, audio and other information, a television receiver may experience a delay before receiving and decoding new information related to the program when a user selects a new channel. For example, the proposed ANSI / EIA-608A technical specification for the transmission of the XDS program classification package states that the program classification package shall be repeated at intervals not exceeding three seconds unless delayed by subtitling data. Subtitling data always take priority as required by law. So if subtitles of field 2 are present, the transitions of the program's classification pack can be delayed up to three seconds. Therefore, when a user selects a new channel, the television receiver may take several seconds to detect and decode information related to the new program and take the appropriate blocking action. The delay is a notable period during which a probably objectionable program remains unblocked and can be viewed by audiences unintentionally. A user may attempt to exploit the aforementioned delay and bypass this blocking feature by repeatedly tuning to a particular channel to see or hear portions of an objectionable program before the blocking feature can be activated. For example, the user can continuously reselect the same channel or continuously switch between two or more channels to see or hear significant portions of an objectionable program. Therefore, what is needed is a system to prevent a user from exploiting the delay associated with detecting, decoding and examining information related to programs, in order to bypass the blocking feature.

The present invention overcomes the difficulties noted above by providing a system that prevents a user from taking advantage of the time delay noted above. The present invention is particularly suitable for use in signal output devices that can be tuned to one of a plurality of signal channels and provide video and / or audio signal outputs. These devices include, but are not limited to, television receivers, digital satellite receivers, video tape recorders, video disc players and audio signal receivers. The present system comprises a signal processor that provides an output signal associated with a program signal of a selected signal channel and controls the user's access to the program signal in response to a determination of whether the information related to the program , included in the program signal, satisfies a blocking criterion selected by the user. The blocking criteria selected by the user can take many forms including, but not limited to a particular blocking level of qualification, in which case the system avoids user access to the output signal if the information related to the program received equals or exceeds the level of blocking rating selected by the user. Information related to the program may include, but is not limited to, the viewer's recommended age ratings, program content ratings, program title, and program summary. After activation of a suitable blocking mode, if a new signal channel is selected and a predetermined sequence of signal selections is detected, the signal processor automatically controls the output signal associated with a newly selected channel in a previously determined to prevent the user from accessing the program associated with the newly selected signal channel and continues this control at least until the processor determines whether the blocking criterion is satisfied with respect to the newly selected channel. Preferably, the signal processor continues this control of the output signal at least until the information related to the program is determined and compared to a blocking level selected by the user. The output signal is controlled in a predetermined manner to prevent user access to the signal of the particular program. It will be understood that this manner of control includes any process or modification to the program signal that makes the program or portions of the program visually and / or auditorily incomprehensible to the user, including, but not limited to, interrupting the signal path, replacing the normal program signal with a blocking level, mix the output signal and / or replace the output signal of the normal program with an on-screen display (OSD) signal representing a message displayed indicating the activation of the blocking feature . These control methods advantageously result in, for example, erasing the video portion, mute the audio portion and disabling the subtitles associated with the program. The predetermined sequence of channel selections may comprise a predetermined number of reselections of the previously selected channel and / or reselections of two or more channels. The present system can be configured in such a way that the aforementioned way of avoiding access to the user only occurs if the newly selected channel had information related to the previously detected program that satisfies the blocking criteria selected by the user. By automatically controlling the output signal in the aforementioned manner when a predetermined sequence of channel selections is detected, the present invention prevents a user from having access to objectionable material during the time of delay when the information related to the program is detected and a determination is made as to whether the blocking criterion is satisfied. The present system can also be configured so that the blocking feature is activated only if a user selects an appropriate blocking mode. The present system can also be configured such that the blocking feature is activated only if at least a particular number of predetermined sequences of signal sections are presented over a particular time period. The invention will be described with reference to the accompanying drawings, wherein: Figure 1 is a block diagram of a television system embracing the principles of the present invention; Figure 2 is a flow diagram showing the steps for changing a channel in a television system that does not provide protection against attempts to bypass a blocking system based on information related to the program; and Figures 3-4 are flow charts showing the steps for changing a channel in a television system according to the present invention that provides protection against attempts to bypass a blocking system based on information related to the program. An exemplary television receiver system 10 shown in Figure 1 includes an input terminal 100 that receives radio frequency (RF) television signals, for example, from an antenna or cable, and applies the television signals to the tuner assembly 105. The tuner assembly 105 selects and amplifies a particular radio frequency signal associated with the selected television channel in response to control signals from the controller 110. As used herein, the terms "controller", "control processor", "microprocessor" (or μ.P), and "microcomputer" (or μC) are equivalent and refer to devices that may or may not be in the form of an integrated circuit (IC) and are capable of performing control functions. As shown in Figure 1, the controller 110 includes the central processing unit (CPU) 112, the read only memory 114 (ROM) and the direct access memory 116 (RAM) interconnected via the bus 111 (bus) and that operate in the typical way of microcomputers such as the integrated circuit ST9 (IC) manufactured by SGS Thomson, Inc. The central processing unit 112 generates control signals to control the output of the system 10 in response to the software instructions stored in the read-only memory 114 and in the electrically erasable programmable read-only memory 127 and as response to commands provided by the user and received through the keypad 120 and / or the infrared (IR) receiver 122. The controller 110 receives command codes from the infrared remote control 125 via the infrared receiver 122. The Control signals generated by the controller 110 are provided to other components of the system 10, such as the tuner 105, via a control busbar represented by the path labeled CTRL_BUS in Figure 1. A typical implementation of the control busbar shown in Figure 1, includes, but is not limited to, two control rods in series of two wires based on the protocol of ba Inter-integrated circuit collector (IIC or I2C) supported by Philips. The infrared remote control 125 and / or the keyboard 120 allow a user to select a particular blocking criterion to automatically block objectionable material. Blocking criteria can take many forms, including, but not limited to, blocking a program if information related to the associated program, such as program ratings, equals or exceeds a user-set information or a rating level. An example of an alternative blocking criterion is to activate the blocking in response to detect a word or words specified by the user in the title or in the program description information included in the information related to the program. The blocking criterion selected by the user, which may have a level of qualifications as noted above, is stored in the controller 110 and is examined by the central processing unit 112 to lock or unlock a program as further described below. . The selection of the user can be done, for example, by selecting a particular blocking mode and / or blocking level from a screen display menu. When a user selects a particular television channel by activating either the keypad 120 or the remote control 125, the controller 110 produces a control signal in the busbar CTRL_BUS which causes the tuner 105 to tune the radio frequency signal of the selected channel. The tuner 105 produces an intermediate frequency (IF) signal corresponding to the channel tuned to the intermediate frequency processor 130. The intermediate frequency processor 130 includes circuits such as, but not limited to, a video intermediate frequency amplification stage ( VIF), an AFT circuit, a video detector, and an intermediate frequency sound amplification (SIF) stage to process the intermediate frequency signal to produce the VIDEO baseband composite video signal and the sound carrier signal AUDIO. The audio signal processor 135 includes an audio detector and a stereo decoder that processes the audio signal to produce a convenient baseband audio signal for driving the loudspeaker unit 136. The baseband composite video signal VIDEO of the intermediate frequency processor 130 is applied to the video switch 140. Another video signal, VIDEO IN, can be provided to the present system by a source of external signals, for example, a video cassette recorder, via the signal of input 102. The external signal source can also provide an audio signal, AUDIO IN, via the input signal 101. The controller 110 controls the respective output of the video switch 140 and the audio processor 135 in response to the selection of the audio signal. user of a source of particular signals. It will be understood that a plurality of external signal inputs can be provided to accommodate a plurality of external signal sources, and the video signal switch 140 and the audio processor 135 may be modified as necessary to allow the user to be selected from a particular external signal source. Depending on the selection of the user, the video switch 140 provides the VIDEOl signal, which is associated with one of the input signals, to the video signal processor 155. The video signal processor 155 processes the video signal VIDEOl. to produce red, green and blue (R, G and B) RGB output signals which are convenient for coupling with an image display device. The video signal processor 155 performs processing to provide, among others, automatic chrominance and luminance control and allow user-controlled features such as contrast and brightness control. The RGB signals produced by the video signal processor 155 are amplified at approximately appropriately high voltage levels by the kinescope impeller amplifiers 156 before being coupled to the kinescope 158 to display the desired image. The display on the kinescope 158 is controlled by the vertical and horizontal flexural deformation signals VR and HR, respectively, which are coupled with the flexure deformation coils of the kinescope 158. The flexure deformation unit 170 produces the HR signals and VR in response to the vertical and horizontal synchronization signals HS and VS, respectively, which are separated from the synchronization component of the VIDEO output baseband signal. The parts of the system in Figure 1 that have been described so far are known, for example, from the CTC-197 color television chassis manufactured by Thomson Consumer Electronics, Indianapolis, Indiana. The system shown in Figure 1 also includes an auxiliary data processor 115 for detecting and decoding various auxiliary information, including information related to programs, such as program ratings and / or content ratings, included with a video signal. Also, subtitle decoding functions may be included within the auxiliary data processor 115 which is coupled with the on-screen display (OSD) processor 117 in order to insert subtitle information into suitable portions of the video display. Data processors for extracting auxiliary information from a video signal are conventionally known and typically include a data splitter, timing signal generators, control mechanism, decoders and memory, among other things. Any other of several conventionally known auxiliary data processors may be used in the present television system. For example, a convenient system for extracting auxiliary information from a video signal is described in U.S. Patent No. 5,561,469 entitled "Auxiliary Video Data Slicer with Multi-Mode Peak Detection for Determining Sync and Data Slicing Levéis". The auxiliary data processor 115 detects and decodes information related to the program, such as program ratings, included in the VIDEOl signal and provides information related to the program to the central processing unit 112. The central processing unit 112 examines the information related to the detected program and determines if a blocking criterion selected by the user is satisfied, for example, by comparing the information related to the detected program with the blocking level selected by the user and determining if the information related to the detected program equals or exceeds the blocking level selected by the user.

If the blocking criterion selected by the user is satisfied, the central processing unit 112 returns to the inaccessible program by controlling the output signal, in a predetermined manner. It will be understood that this manner of control includes any process and modification to the signal of the program returning to the program, or portions of the program, visually and / or auditorily incomprehensible to the user as noted above. For example, the controller 110 provides control signals to disable the output of the audio processor 135, disable the subtitling output, and replace the normal program signal with a suitable on-screen display signal, such as a uniform blue screen that includes a message that indicates the activation of a blocking feature. If the information related to the detected program does not meet the blocking criteria selected by the user, the central processing unit 112 allows the video signal processor 155 and the audio processor 135 to provide output signals associated with the signals received from the receiver. the conventional way. Figure 2 is a flow diagram showing the steps taken by a television system that is not configured to prevent a user from exploiting the delay discussed above. When a user initiates a channel change in step 200, the television system performs a channel erasure in step 202, tunes to a newly selected channel in step 204, and then stops erasing the television display in step 206. That is, the newly selected channel is momentarily cleared while the channel is being tuned, but immediately it is cleared after the tuner 105 tunes the program signal associated with the new channel. After the new channel has been tuned and stopped erasing, the television system determines whether the V-chip channel lock feature is enabled in step 208. If not, the system exits the program in step 210. If the lock feature is enabled, the system sets a V-chip packet timer to zero and starts incrementing the stopwatch in step 212. The television system then monitors the XDS 21 data line for information related to the program in the step 214. As soon as an information packet related to the valid XDS program has been detected and decoded in step 216, the system resets the V-chip packet timer to zero and begins by incrementing the chronometer in a predetermined manner in step 220 The system then compares the information related to the newly detected program with a blocking level selected by the user in step 222 to determine if it is satisfied the blocking criteria selected by the user. If the blocking criterion is satisfied, that is, the information related to the newly detected program equals or exceeds the blocking level selected by the user, the system blocks the user's access to the channel in step 226 by controlling the output signal as described above, and returns to step 214 to repeat the process of detecting and comparing the information related to the program and blocking / unblocking the channel as necessary. If the blocking criterion is not satisfied, that is, the newly detected program information is less than the blocking level selected by the user in step 222, the system allows the user to access the program associated with the newly selected channel. and return to step 214 to repeat the monitoring and blocking process as noted above. Also, if the television system fails to detect new information related to the program within a predetermined period of time as determined by the V-chip packet timer increment, the television system will allow the user access to the channel, or will keep the channel unlocked, and return to step 214 to repeat the process as noted above. Therefore, the television system continuously tries to detect new information related to the program and determine if the blocking criterion selected by the user is satisfied to control the user's access to the signal of the received program. However, it can be seen that the user's access to the channel is presented in step 206 before the detection of the new information related to the program and the determination of the blocking criteria are satisfied when a user selects a new channel. As discussed above, a significant amount of time may elapse before new information related to the program is detected and processed, possibly allowing unwanted access to objectionable material. Figures 3-4 are flow charts showing the steps performed by a system according to the present invention which provides protection against a user's attempt to exploit the aforementioned delay. The features shown in Figures 3-4 can be enabled and controlled by a user, for example, using a screen display menu. The access to enable and control the blocking features can be password protected, that is, it requires a user to enter a correct password to prevent unauthorized users from modifying previously fixed establishments. Methods for incorporating these features and the steps described below can be programmed in the controller 110 using conventionally known methods.

Again, when a user initiates a channel change in step 230, the present system performs a channel change deletion in step 232 and tunes to the new channel in step 234. However, after tuning in the new channel, and before ceasing to erase the television display, the present system determines whether the channel blocking feature based on information related to the program is enabled by the user in step 236. If not, the system allows the user access to the channel. user to the channel in step 264 and exits the program in step 266. If the channel blocking feature is enabled, the present system determines in step 238 whether the newly selected channel is the same as the channel previously selected in step 238. This determination may provide an indication that the user is continually re-tuning the same channel in an attempt to bypass the information-based blocking feature. n related to the program. If the newly selected channel is the same as the previously selected channel, the system can go through two optional additional steps or go immediately to step 268 where the user's access to the new channel is avoided and the process of determining a related information with the program and if the blocking criterion selected by the user is satisfied, it is done after that.

In the optional first step 246, the system determines whether the newly selected channel previously contained objectionable material as indicated by the information related to the previously detected program. Using the information related to the program previously detected, the information related to the required program is enabled so that it is determined quickly. Step 246 may further include a determination of whether information related to the previously detected program of the newly selected channel was detected within a predetermined period of time. This avoids a decision to delete / stop deleting a channel from being based on information related to the program that is no longer relevant. For this purpose, information related to the program of the previously selected channel and / or the channel prior to the previously selected channel can be stored in the controller 110 for a predetermined period of time. Alternatively, a counter or a stopwatch can be used to determine how long information related to the stored program was determined. Conventional methods can be used to store information related to the previously detected program and to determine how long the information was detected. If the information related to the previously detected program of the selected channel again does not indicate objectionable material within a predetermined period of time, the present system allows the user access to the channel through the steps 242 and 244. It can be seen that the Optional step 246 allows the user to quickly switch back to a previously selected channel when the user does not attempt to deviate from the blocking system based on information related to the program. If the present system determines an optional step 246 that the information related to the previously detected program of the newly selected channel indicated objectionable material, the optional step 261 may be inserted to determine whether the user is repeatedly re-tuning to the same channel. Continuous re-tuning to the same channel by at least a predetermined number of times is an additional indication that the user is trying to deviate from the blocking feature based on information related to the program. Requiring a predetermined number of re-tunes can avoid the inconvenience to users of not trying to bypass the blocking feature. Optional step 261 comprises updating a counter of the same channel in step 260 and comparing the counter of the same channel with a preselected value, which can be preprogrammed or selectable by the user. If the counter of the same channel is less than a pre-selected / preprogrammed value, the system allows user access to the channel in step 244. However, if the counter of the same channel equals or exceeds the pre-selected / preprogrammed value, the present The system avoids user access to the new channel and continues to detect the information related to the program and determine if the blocking criteria selected by the user in steps 272-284 are met. It can be seen that steps 270-284 correspond to steps 212-226 of the system described above, in relation to Figure 2. Essentially, the present system seeks to continuously detect information related to the program within a predetermined amount of time, then it determines whether a blocking criterion selected by the user is satisfied by comparing the information related to the detected program with the information related to the program selected by the user and controls the user's access to the selected channel based on the determination. In addition, the present system provides an additional layer of protection against attempts to bypass the blocking feature of information related to the program by continuously switching between two different channels. This protection is provided by steps 240-244. As soon as the system determines in step 238 that the newly selected channel is not the same as the previously selected channel, step 240 determines whether the newly selected channel is the same as the immediately selected channel before the previously selected channel. An affirmative response to step 240 indicates that the user may be switching back and forth between two channels to exploit the delay time discussed above. In that case, the system again goes to optional step 246 to determine if the objectionable material was indicated on the selected channel before the previously selected channel, and if so, prevents access to that channel. Again the optional step 261 can be inserted to allow a predetermined number of channel changes before the blocking feature is triggered based on information related to the program. If the optional steps 246 and 261 are not present, the system goes to step 268 to keep the new channel deleted. It can be seen that step 240 can be modified as necessary to prevent the user from deviating from the blocking system based on information related to the program by rotating through a predetermined number of channels. If the newly selected channel is not the same as the channel previously selected to the channel prior to the previously selected channel, the present system sets the counter of the same channel to zero in step 242, allows the user access to the channel in step 244 and it routinely detects information related to the program and determines if a blocking criterion selected by the user is satisfied as indicated in steps 270-284. It will be apparent to those skilled in the art that while the invention has been described in terms of an exemplary embodiment, modifications and changes can be made to the embodiment described without departing from the essence of the invention. It is not known herein that the channel deletion described above can be carried out using any of a number of conventionally known methods, or combination of methods, for example using the normal channel change erasure mechanism already built in a receiver. signal together with another erase mechanism to provide additional erasure beyond the normal channel change erase period, or using the normal channel change erasure mechanism where the erase period is extended as desired. Also, the present series of steps shown in Figures 3-4 can be implemented for a variety of signal formats, both analog and digital, where auxiliary information is included with program signals. The aforementioned system and method can be adapted for use with any signal detector system that can tune to one of a plurality of signal channels and provide the output signal associated with the tuned signal channel. As such, the present invention can be adapted for use with, but not limited to, televisions adapted for NTSC, PAL or SECAM signals, digital television receivers, such as digital satellite signal receivers and HDTV receivers, video cassette, and systems of audio / video programs based on Internet. In addition, the present apparatus can be modified to compile a record of the number of attempts to reselect a channel that often includes objectionable programs. The compiled record can then be used to automatically block certain channels or give the user an option to exclude certain channels. Additionally, the present apparatus can be modified to control the output signal in a predetermined manner based on the number of attempts to reselect a particular channel in a given period of time. Again, this apparatus may be equipped with a registration mechanism to provide a record of the sequence of channel selections and to automatically block or give the user an option to block certain channels. Using the present apparatus together with a chronometer and a record of the sequence of channel selections, the apparatus can automatically block or give the user an option to block certain channels for a certain period of time. In addition, the present apparatus can be adapted for use with a television system having multiple signal inputs, wherein the apparatus automatically locks an output signal associated with an external signal source, after the user selected from the source of external signal, at least until the information related to the program associated with a program signal of the external signal source is detected, and a determination of whether the blocking criterion selected by the user is satisfied for the program signal to after the external signal source is made. Therefore, it will be understood that the present invention is intended to cover all modifications that would fall within the true scope and spirit of the present invention.

Claims (13)

1. An apparatus, comprising: a data receiver (120, 122) for receiving selections of a user's signal channel; a signal input (100, 105) for receiving a program signal associated with one of a plurality of signal channels, the signal input selects one of the plurality of signal channels in response to the signal channel selection; a signal output (RGB OUT) to provide an output signal derived from the program signal; an auxiliary data decoder (115) for detecting information related to the program included in each program signal; and a processor (112) operatively connected to the data receiver, the signal input, the signal output and the auxiliary data decoder, wherein the processor controls the output signal in a predetermined manner to reduce the user's access to the signal of the program when a predetermined sequence of selections of signal channels is received. The apparatus according to claim 1, wherein the processor controls the output signal in the predetermined manner for at least until the information related to the program is determined when the predetermined sequence of signal channel selections are received. . 3. The apparatus according to claim 1, wherein the signal of the program is a television signal. The apparatus according to claim 1, wherein the program signal comprises a plurality of digital signal packets. The apparatus according to claim 1, wherein the predetermined sequence of selections of signal channels comprises a predetermined number of consecutive selections of a particular signal channel. The apparatus according to claim 1, wherein the predetermined sequence of selections of signal channels comprises a predetermined number of consecutive selections of the particular signal channel, a second signal channel and the particular signal channel. The apparatus according to claim 1, wherein wherein the processor controls the output signal in the predetermined manner when the predetermined sequence of selections of signal channels is received and a first blocking mode is selected. The apparatus according to claim 7, wherein the processor is capable of providing an on-screen display menu to allow user selection of the first blocking mode. The apparatus according to claim 8, wherein the processor is capable of providing restricted access to the on-screen display menu to allow user selection of the first blocking mode. The apparatus according to claim 9, wherein access to the restricted access of the on-screen display menu is password protected. The apparatus according to claim 1, wherein the predetermined way of control comprises one of erasing the video signal, replacing the video signal with a screen display message, muting the audio signal and disabling subtitling. The apparatus according to claim 1, wherein the processor controls the output signal in a predetermined manner when the predetermined sequence of the signal channel selections is detected, unless the information related to the program was previously determined to be within an acceptable level within a predetermined period of time. The apparatus according to claim 1, further comprising a second signal input (101, 102) for receiving a second program signal from an external signal source, and a switch (140) operatively connected to the signal input, the second signal input, the output signal and the signal processor, the switch operably couples a respective one of the program signal and the second program signal with the signal output in response to a source selection of signal from the user, wherein the signal processor controls the output signal in a predetermined manner to reduce the user's access to the output signal for at least until the information related to the program is determined when a selection is received of new signal sources. SUMMARY An apparatus and method for preventing a user from overlooking a viewer blocking system by using information related to the program, such as the content rating, included in a program signal. The present invention prevents the user from taking advantage of the time delay associated with detecting, decoding and comparing information related to the program by changing channels to observe portions of objectionable programs before the blocking system can react. The present system comprises a processor (110) which controls the output of a selected program signal (VIDEO, VIDEO IN, AUDIO IN) in response to a determination of whether an information related to the associated program satisfies a blocking criterion selected by the user. The processor blocks the display of a program signal when a predetermined sequence of signal channel selections is detected and then continues to block the display of the program signal at least until the determination is carried out. The predetermined sequence of selections of the signal channel may comprise the continuous retuning of the same channel and / or switching between two channels. The present method comprises detecting a particular sequence of selections of signal channels and blocking the display of the program signal after detecting the predetermined sequence. If the predetermined sequence of the selections of the signal channel is detected, the blocking of the display is maintained at least until a program-related information associated with the signal of the program is detected and a determination of the satisfaction of a program is carried out. blocking criteria selected by the user.