WO2000052933A1

WO2000052933A1 - Automatic filtering method and device for audio-visual signals

Info

Publication number: WO2000052933A1
Application number: PCT/FR1999/000500
Authority: WO
Inventors: Laurent Urban; Alain Allal
Original assignee: Laurent Urban; Alain Allal
Priority date: 1997-08-28
Filing date: 1999-03-04
Publication date: 2000-09-08
Also published as: FR2768002B1; AU3258599A; FR2768002A1

Abstract

The invention concerns a method for filtering audio-visual signals which consists in: identifying the characteristics of a predetermined code likely to be emitted by an audio-visual broadcaster within its audio-visual signals; continuously searching for the presence of such a code in the received signal; and applying to said signal a scrambling procedure when the presence of said predetermined code is detected, otherwise the signal is transmitted in the form it is received.

Description

TITLE of the INVENTION

Method and device for automatic filtering of audiovisual signals

The invention relates to a method and a device for filtering audiovisual signals, and to an audiovisual device, such as a television or video recorder comprising such a device.

There are today a number of methods for coding or prohibiting the reception of audio or video sequences. Among these, a clock-based system makes it possible to prohibit free-to-air broadcasting on a given date and time slot.

Another system prohibits the ignition of reception stations without allowing selection of the broadcast images.

In general, these different methods are not linked to the content of the program and do not analyze the signals received permanently.

The present invention relates to a method and an electronic device (which may be called a “censor”) which makes it possible to selectively and automatically censor audiovisual programs as a function of the signage put in place on television by the CSA or other public entities. or private for the protection of children, adolescents and sensitive persons.

The presence of anti-violence acronyms affixed at the bottom of the screen (orange triangle, red square, green circle) is currently a simple indicator used to warn viewers of the degree of violence or eroticism of a program. The signage issued by the various television channels does not eliminate the risk that certain sensitive people, children or adolescents in the event of lack of vigilance on the part of those responsible will not look at images that are difficult to defend. The object of the invention is to allow filtering of television broadcasts (or even video programs) independently of any obligation of vigilance, automatically.

To this end, the invention proposes a method of filtering audiovisual signals according to which: - the characteristics of a predetermined code capable of being transmitted by an audiovisual broadcaster in its audiovisual signals are identified;

- We continuously search for the presence of such a code in a received signal; and

- a scrambling procedure is applied to this received signal when the presence of this predetermined code is detected, otherwise the signal is transmitted as received.

According to preferred arrangements of the invention, possibly combined:

- We analyze the signal received by successive slices, and we look for the code in each of these slices;

- each section corresponds to an image;

- the filtering procedure is applied to each section in which the code has been detected;

- the characteristics of a plurality of predetermined codes capable of being transmitted in said audiovisual signals are identified, the presence of any of these codes is sought in a received signal and the scrambling procedure is applied when the presence of the 'any of these codes is detected;

- We analyze the signal received by successive slices each corresponding to an image and, when said codes are likely to be in the same image area, we search for any of the codes only in this image area. The invention also provides a device for filtering audiovisual signals comprising:

- an input interface adapted to receive an audiovisual signal;

- an output interface adapted to provide a filtered signal; - a storage area containing the characteristics of a predetermined code capable of being transmitted by an audiovisual broadcaster in its audiovisual signals;

a comparison means connected to the input interface, to the storage area and to the output interface and designed so as to search the received signal for the possible presence of the characteristics of said code;

a scrambling means connected to the comparison means and to the output interface and adapted to apply to the signal a predetermined scrambling procedure when the comparison means detects the presence of said code and, if not, to be applied to the signal output interface as is.

According to other preferred arrangements of the invention, possibly combined:

a processing stage is interposed between the input interface and the comparison means, designed so as to decompose the received signal into successive slices, the comparison means being designed so as to search for the possible presence of the code in each of these slices;

the processing stage is designed so as to decompose the signal into representative slices of images;

the scrambling means is designed so as to apply the scrambling procedure to each slot in which the code has been detected;

the storage area contains the characteristics of several codes capable of being transmitted in the audiovisual signals, and the comparison means is designed so as to search in the signal for any one of said codes; - This device further comprises a panel provided with keys corresponding to said codes and intended to allow a user to select the code or codes whose presence must activate the jamming procedure;

- the input and output interfaces are part of a SCART type socket. The invention also covers an audiovisual device such as a television or video recorder (to prevent the recording of sensitive programs) or even a computer comprising such a device.

Objects, characteristics and advantages of the invention appear from the following description, given by way of nonlimiting illustrative example, with reference to the appended drawings in which:

- Figure 1 is a block diagram of a device according to the invention;

- Figure 2 is a schematic view of a keyboard or panel accessible to a user; - Figure 3 is a block diagram showing the principle of detection in an image or on a screen;

- Figure 4 is a block diagram of the video analysis part;

- Figure 5 is a block diagram of the jamming part (or scrambler); - Figure 6 is a block diagram of a first example of application of a device according to the invention;

- Figure 7 is a block diagram of a second application example;

- Figure 8 is a block diagram of a third application example;

- Figure 9 is a front view of a female SCART socket; and

- Figure 10 is a side view of a male scart socket according to an independent and original aspect in itself of the invention.

The following description relates to a device which has a video or audio video encoder that activates automatically when an acronym (in our example: triangle, square, circle) previously selected by the operator is detected in the image. The implementation of this device can be broken down in different ways, here are two non-limiting examples:

1) Integration into an audiovisual reception system at the time of its design and then its manufacture (television, monitor, video recorder, satellite receiver, digital terminal, computer or any current or future system allowing the reception of audiovisual programs or the reproduction of images ). This solution is very secure in terms of its implementation but requires the change of all or part of the devices mentioned above. 2) Independent device connected to the audiovisual reception system by a SCART cable.

This solution allows its installation on all types of existing audiovisual devices equipped with SCART sockets. The latter system is secured by using a male SCART socket with integrated lock to avoid any disconnection with the audiovisual or other device and a self-powered system by built-in accumulator forcing the slow switching of said device in order to prohibit any plain text display. censored programs in the event of a power failure.

The realization of this device implements the use of the following three technologies:

O Digitization of a video signal

The advantage of this invention compared to the existing products is of obvious social interest by the automatic and permanent censorship of the emissions incorporating aggressive or shocking images, releasing the parents or the persons in charge of a follow-up often badly carried out because constraining .

The operating principle is presented in figure 1. Input of analog signals (video and sound)

Conversion of video signal to digital. It is processed in real time in a quick access RAM. Calculations are performed on this signal to determine the values sought (dimensions, position, shape, in our example the triangle, the square and the circle).

The results are made available to a computer which compares the data to that contained in a file containing the elements of definition of the three forms described above as well as their positioning in the image.

In order for the search to be carried out, it is necessary to enter the data (conditional access by electronic or mechanical key) which will allow the computer to search for the acronym (s) corresponding to the desired level of censorship.

When all the conditions listed above are met, the "self-censoring" device is then activated, until the complete disappearance of the anti-violence symbol in the image.

Thus, the device according to the invention is particularly intended for all those who wish to give a certain form of intelligence to their television set and more generally to any video reception system by making it possible to automatically censor programs comprising scenes likely to strike or disturb sensitive people and more particularly young people. The keyboard part is shown in Figure 2.

The keyboard is locked by a mechanical or electronic key allowing access to programming.

Example: 3 illuminated buttons in the shape of three anti-violence symbols and a key switch. To access the programming, it is necessary to insert the key into its housing and put it in the ON position.

Thus the three luminous buttons flash, materializing the possibility of accomplishing the programming.

This is done by impulse on one or more of the buttons mentioned above which pass from the flashing phase to a constant lighting. Storage is effective when the key is placed in the OFF position.

(It is possible to select all acronyms).

An extension of the keyboard is possible so that the locking can be extended to an unlimited number of channels or video cassettes as soon as they emit an acronym or logo anywhere in the image.

The keyboard data is analyzed by a keyboard decoder, which can possibly be a microprocessor, which will validate the switching circuit as soon as the programmed acronym (s) appear on the screen. Each introduction of the key into its housing causes a reset of the system and requires a new programming.

For no censorship to be effective, simply insert the key into its housing, place it in the ON position, and return to the OFF position without any action on the illuminated push buttons. After this operation, none of the illuminated keys are lit.

In the case where the system is integrated into a television or any other audiovisual device, the keyboard is replaced by a remote control which controls the internal microprocessor thereof and the instructions are then displayed directly on the screen of the device (OSD ). As can be seen from FIG. 3, the binary data originating from the conversion of YC are compared with the programmed values (O D Δ) during the time ΔP from line N to line N + n.

The circuit can scan the ΔP from the end of the SC

(Sand Castle) until the end of the -ΔP line.

It is thus possible to detect any acronym or logo anywhere in the image and start the analysis from the first lines in the frame. The number of sampling points per line must be large enough to allow a correct definition of the analysis: example 800 points / line. The scrambler part (see Figure 5) can be made from any type of existing system (video delay, line inversion or line part, etc.) or new.

In our example, we present a character or image generation system on a black or white screen depending on the types of connected audiovisual devices.

The scrambler operates continuously and is only active on the screen if all of the following conditions are met:

- device connected to a mains power socket (220V 50Hz); - SCART socket connected to television or other;

- self-censorship programming carried out;

- key in OFF position (preferably removed from its housing);

- anti-violence symbol present on the channel watched.

For the sound part, several techniques can be used (frequency modification by chopping or mixing, etc.) but the simplest and nevertheless very effective, is to cut it.

The invention lends itself to protection of use.

A) Internal use:

In this specific case, the operation is very secure because no action is possible to deactivate self-censorship apart from knowing the access code to the programming.

B) External use:

The fact of using an independent box requires that it be equipped with the following two devices: 1) Protection by accumulator in the event of disconnection of the 220 V (50Hz) mains power socket. Thus the slow switching of the audiovisual device is forced via the SCART socket and causes the appearance of a black or white screen depending on version.

2) Lockable SCART socket. Prohibits the disconnection of the male SCART socket once connected to any audiovisual device.

Figures 6 to 8 show several application examples. This system has the advantage of being scalable and thus corresponding to all types of needs in very varied fields such as television, video, IT, multimedia and any other medium.

- The example chosen for this patent is television with the use by 5 French channels of the anti-violence acronyms created by the CSA.

This application of CSA signage can be extended to other French or foreign channels in radio, satellite or cable broadcasting.

The system can be adapted for the recognition of other acronyms or logos that can be used by any other broadcaster. Other detection choices are possible: (specific signal in video or sound).

The use of acronyms CSA or other system described above can be applied to video cassettes (or any other current and future support) for sale or rental and thus prohibit their viewing at the time of their reading.

According to an aspect of the invention, original in itself, the device comprises a locking scart socket (Figures 9 and 10).

The device according to the invention makes it possible to lock a male scart socket once inserted into a female scart socket of any video or other device using this type of connection.

The advantage of this system lies in the fact that more and more devices come to interconnect with each other and for security reasons, in certain cases, it is sometimes necessary to prohibit their disconnection (example: video elevator) . The above-mentioned device allows male / female locking by a mechanical principle integrated in the male scart socket.

A lug articulated around an axis at its center and connected to a lock at its end engages in any female scart socket existing on the market today. NOTE: We can notice on all female SCART sockets fitted to video devices the presence of a 1.5 mm wide slot and length approx. 4 mm. It is this slot which allows the realization of the present invention.

This description is an example and is therefore not limiting.

There can be many variations, including signal input which can be directly digital.

Claims

1. A method of filtering audiovisual signals according to which: - the characteristics of a predetermined signage code capable of being transmitted by an audiovisual broadcaster in its audiovisual signals are identified;

- We continuously search for the presence of such a code in a video / sound signal from the received signal; and - a scrambling procedure is applied to this video / sound signal when the presence of this predetermined code is detected, otherwise it is transmitted as it is.

2. Method according to claim 1, characterized in that the signage code is a code intended to be visible in images originating from the signal, and this code is sought in the video signal.

3. Method according to claim 1 or claim 2, characterized in that the signal received is analyzed by successive sections, the code is sought in each of these sections, and the filtering procedure is applied to each section in which there is detected the signage code.

4. Method according to claim 3, characterized in that each slice corresponds to an image.

5. Method according to any one of claims 1 to 4, characterized in that one identifies the characteristics of a plurality of predetermined signage codes capable of being transmitted in said audiovisual signals, one searches for the presence of the any of these codes in a video and / or sound signal from this received signal and the scrambling procedure is applied when the presence of any of these signage codes is detected.

6. Method according to claim 5, characterized in that the signal received is analyzed in successive sections each corresponding to an image and, when said signage codes are likely to be found in the same image area, one searches for any of the codes only in this image area.

7. Audiovisual signal filtering device comprising:

- an input interface adapted to receive a video and / or sound signal,

- an output interface adapted to supply a filtered video and / or sound signal,

- a storage area containing the characteristics of a predetermined signage code capable of being transmitted by an audiovisual broadcaster in its audiovisual signals;

a comparison means connected to the input interface, to the storage area and to the output interface and designed so as to search the video signal and / or its for the possible presence of the characteristics of said sign code, a jamming means connected to the comparison means and to the output interface and adapted to apply to the video signal and / or its a predetermined jamming procedure when the comparison means detects the presence of said signage code and, in the case on the contrary, to apply the signal as it is to the output interface.

8. Device according to claim 7, characterized in that, the signage code being intended to be visible in images from the signal, the comparison means is designed so as to search for the presence of this code in the video signal.

9. Device according to claim 7 or claim 8, characterized in that a processing stage is interposed between the input interface and the comparison means, designed so as to decompose the received signal into successive slices, the means of comparison being designed so as to search for the possible presence of the code in each of these slices, and the scrambling means being designed so as to apply the scrambling procedure to each slice in which the code has been detected.

10. Device according to claim 9, characterized in that the processing stage is designed so as to decompose the signal into representative slices of images.

11. Device according to any one of claims 7 to 10, characterized in that the storage area contains the characteristics of several signage codes capable of being emitted in the audiovisual signals, and the comparison means is designed so as to search the signal for any of said codes.

12. Device according to claim 11, characterized in that this device further comprises a panel provided with keys corresponding to said signage codes and intended to allow a user to select the one or those of the codes whose presence must activate the jamming procedure .

13. Device according to any one of claims 7 to 12, characterized in that the input and output interfaces are part of a SCART type socket.

14. Audiovisual apparatus comprising a signal input interface and an image output means, between which is connected a device according to any one of claims 7 to 13.

15. Apparatus according to claim 14, characterized in that the output means is a display screen.