JP5161655B2 - Anti-voyeurism device - Google Patents

Description

  The present invention relates to a voyeurism prevention device that prevents illegal copying of video content projected on a screen.

  With the development of digital technology, digital recording / reproducing apparatuses in which the image quality does not deteriorate even when repeated recording / reproducing is in widespread use. In addition, media such as DVDs and CDs on which various video contents are recorded are distributed and sold in the market, and various video contents are distributed through a network.

  In digital recording / reproduction, data deterioration does not occur even when recording / reproduction is repeated, so that the same quality as the original data is maintained. The spread of such a digital recording / reproducing technique causes a flood of illegal copies, which is a big problem from the viewpoint of copyright protection. In particular, when new video content is projected in a movie theater or a theater, there are many cases where video content projected on a screen is voyeurized by a video camera, copied without permission, and then secondarily distributed. Such a situation is a big problem from the viewpoint of copyright protection because the copyright of the new video content is infringed.

  As a technique for preventing video content projected in a movie theater or a theater from voyeurism, a method of switching an image display mode temporally or spatially has been proposed (for example, see Patent Document 1). In this voyeurism prevention technology, the image display mode of video content is switched temporally or spatially between RGB display and RGBY display. By switching the display mode in this way, when video content projected on the screen is captured by a video camera, an image with flicker or uneven color is captured, which is useful in preventing voyeurism.

A technique for protecting the copyright of video content projected on a screen using a digital watermark technique is also known (see, for example, Patent Document 2). In this known technique, an image display device for projecting the name of the copyright holder is provided separately from the image display device for projecting the video content, and the name of the copyright owner is displayed on the video content projected on the screen. Has been.
JP 2003-302960 A JP 2005-26759 A

  The method of switching the display mode described above can degrade the quality of the voyeur image and is beneficial in terms of preventing voyeurism. However, in the image display device, it is necessary to switch between RGB image display and RGBY image display, and there is a drawback that the structure of the image display device becomes complicated. In addition, the RGBY signal must be generated from the input RGB signal, which not only increases the manufacturing cost but also complicates the signal processing circuit. Furthermore, it has been pointed out that the existing image display device cannot be used as it is and a new image display device must be purchased in a movie theater or a theater.

  The digital watermark presenting apparatus described in Patent Document 2 described above is a useful technique as a copyright protection method because the name of the copyright holder is displayed over the video content projected on the screen. However, since the technology is intended to display the copyright holder over the video content, only the name of the copyright owner is displayed over the video content that has been voyeurized. Can not be fully effective.

An object of the present invention is to realize a voyeurism prevention device that can effectively prevent voyeurism with a relatively simple structure.
Another object of the present invention is to realize a voyeurism prevention device that can effectively prevent voyeurism using an existing image display device installed in a movie theater or a theater as it is.

A voyeurism prevention device according to the present invention described as a reference example is a voyeurism prevention device that degrades video content projected on a screen and being viewed without affecting the audience being viewed,
A light source device configured by infrared light having a longer wavelength than the long wavelength end of visible light, and generating interference light that degrades video content;
A projection lens system that projects the interference light emitted from the light source device toward the screen;
Control means for driving and controlling the light source device,
The control means is driven and controlled to generate disturbing light from the light source device at time intervals of a predetermined cycle or at irregular time intervals,
The present invention is characterized in that disturbing light generated intermittently in time is projected on video content projected on a screen.

A typical video camera has three image sensors that photoelectrically convert color-separated RGB color lights. Among these image pickup elements, an image pickup element that picks up red light has a peak sensitivity in a wavelength region near 650 nm, and has a sensitivity not only in the visible range but also on the longer wavelength side than the long wavelength end of visible light. . Accordingly, infrared light having a wavelength longer than the end wavelength on the long wavelength side of visible light is not visually recognized by the viewer, but is perceived by the video camera. Therefore, in the present invention, infrared light in the above-described wavelength range is used as interference light for preventing voyeurism. When interference light is projected from the anti-voyeurism device toward the screen, the interference light is reflected by the screen and scattered toward the audience space. As a result, the disturbing light of the infrared light is incident on the video camera during the voyeurism together with the image light of the video content projected on the screen. An image pickup device that picks up red light of a video camera is sensitive to infrared light, which is interference light. Therefore, when the interference light is projected on a screen, the luminance signal level of red increases extremely and is imaged. In the video content, red is an extremely strong image, and strong color unevenness occurs. Further, when disturbing light is superimposed on video content periodically or irregularly, strong flicker is generated in addition to color unevenness, which gives an unpleasant stress to the viewer. Therefore, the video content voyeurized by the video camera deteriorates into an unpleasant image that cannot be viewed by the viewer. As a result, even if voyeurism is taken, the video content that has been voyeurized loses its sales value in the market, and secondary distribution is effectively prevented.
In the present specification, “infrared light” includes near-infrared light and far-infrared light that is longer than the long-wavelength end of visible light.

  Various light sources that emit infrared light can be used as the light source device. For example, an LED or a laser diode can be used. Further, a combination of a xenon lamp or a halogen lamp and a bandpass filter can be used. Further, when LEDs are used, it is possible to secure a desired light amount on the screen by arranging a plurality of LEDs in an array. It is also possible to form a plurality of light spots on the screen by the disturbing light emitted from the plurality of LEDs and individually control the lighting of the LEDs by the control means. In this case, since light spots that are individually lit on the time axis are formed on the screen, a strong red spot is randomly formed temporally and spatially in the video content sneak shot by the video camera. The video content deteriorates into an unpleasant image that cannot be viewed.

A voyeurism prevention device according to the present invention described as a reference example is a voyeurism prevention device that degrades video content projected on a screen and being viewed without affecting the audience being viewed,
A light source device configured by infrared light having a longer wavelength than the long wavelength end of visible light, and generating interference light that degrades video content;
A diffraction grating for converting disturbing light emitted from the light source device into a plurality of disturbing beams;
A projection lens system that projects a plurality of disturbing beams emitted from the diffraction grating as spots on a screen;
The present invention is characterized in that a spot of interference light is projected on the video content projected on the screen.

  In the present invention, the interference light emitted from the light source device is converted into a multi-beam by the two-dimensional diffraction grating, and a large number of light spots are formed on the screen by the projection lens system. Since this light spot is composed of infrared light, the video content sneak shot by the video camera becomes an image in which a strong red spot is locally formed, causing flicker and color unevenness, which is viewed by the viewer. The image becomes uncomfortable. Therefore, it is extremely effective for preventing voyeurism.

  In this voyeurism prevention device, a multi-beam can be generated by a combination of a laser light source and a two-dimensional diffraction grating, and a spot of interference light can be locally formed on the screen. Therefore, there is an advantage that even if the output capacity of the light source device is relatively low, it is possible to cope with it sufficiently. That is, when projecting interference light with uniform brightness over almost the entire surface of the screen, it is necessary to use a light source device with a considerably large output. On the other hand, in the voyeurism prevention device, since the spot of interference light is locally formed on the screen, a sufficient effect can be achieved even if the output of the light source device is relatively small.

A voyeurism prevention device according to the present invention described as a reference example is a voyeurism prevention device that degrades video content projected on a screen and being viewed without affecting the audience being viewed,
A light source device configured by infrared light having a longer wavelength side than the long wavelength end of visible light, and generating line-shaped interference light extending in a first direction corresponding to a horizontal direction or a vertical direction of the screen;
A projection lens system for projecting disturbing light toward the screen;
Beam deflecting means for periodically deflecting the line-shaped interference light emitted from the light source device in a second direction orthogonal to the first direction;
The video content projected on the screen is scanned with line-shaped interference light that periodically travels along the horizontal or vertical direction of the screen.

By scanning the video content projected on the screen with line-shaped interference light, the video content voyeurized by the video camera has a red band or a strong red turbid band running in the vertical or horizontal direction. It is formed. As a result, the voyeurized video content becomes an unpleasant video content that is difficult to watch for viewers because of strong flicker. Therefore, even if a voyeur is taken, only video content that is difficult to view is voyeurized, which is effective in preventing voyeurism.
Furthermore, in the anti-peeping device, the disturbing light is not projected over the entire screen, but the screen content is deteriorated by scanning the screen with the line-like disturbing light. The advantage is achieved that the video content that is efficiently voyeurized using the device can be degraded.
Here, various deflection devices can be used as the beam deflection means. For example, it is possible to use a motor that rotates over a predetermined angle range, place a light source device on the motor, and scan with line-shaped interference light. Alternatively, a rotating mirror such as a vibrating mirror or a polygon mirror can be used.

A voyeurism prevention device according to the present invention is a voyeurism prevention device that degrades video content projected on a screen and voyeurized by a video camera without affecting the audience being viewed,
A light source device that generates interference light including infrared light on a longer wavelength side than the long wavelength end of visible light;
A diffraction grating for converting the interference light emitted from the light source into a plurality of sub-beams arranged in a line;
Beam deflecting means for periodically deflecting a plurality of sub-beams emitted from the diffraction grating in a direction perpendicular to the arrangement direction;
A projection lens system for projecting a plurality of sub beams emitted from the beam deflecting means as spots traveling on the screen;
The video content projected on the screen is scanned by a plurality of interference light spots that periodically run along the horizontal or vertical direction of the screen.

  In the voyeurism prevention device, since the video content projected on the screen is scanned with a plurality of interference light spots, it is possible to effectively degrade the video content that is voyeurized with much less interference light.

  In a preferred embodiment of the anti-peeping device according to the present invention, a laser light source that emits a laser beam including an infinite number of speckle patterns is used as a light source device, and a polygon mirror (rotating polygon mirror) is used as the beam deflecting means. The projected video content is scanned with a line-shaped disturbing light including an infinite number of speckle patterns or spots arranged in a line. Since the polygon mirror rotates a plurality of mirrors at a high speed, the interference light or the spot of the interference light projected in a line on the video content projected on the screen travels at a high speed. As a result, innumerable flicker is formed in the video content to be voyeurized, and the video content is deteriorated to be unusable for viewing.

A voyeurism prevention device according to the present invention described as a reference example is a voyeurism prevention device that degrades video content projected on a screen and photographed by a video camera located in a spectator space without affecting the audience being viewed. And
A light source device that is arranged adjacent to a screen on which video content is projected, and generates interference light including infrared light having a wavelength longer than the long wavelength end of visible light;
A projection lens system that projects the disturbing light emitted from the light source device toward the audience space from the screen side;
Beam deflecting means for periodically deflecting the disturbing light emitted from the light source device,
The present invention is characterized in that interference light is periodically incident on a video camera which is located in the spectator space and is photographing video content projected on a screen.

  If a voyeurism prevention device is arranged on the screen side and the interference light is projected from the screen side toward the audience space, the interference light emitted from the voyeurism prevention device is directly incident on the video camera being voyeurized, so a light source device with a small capacity It becomes possible to prevent voyeurism effectively by using. As a result, the advantage that the range of selection of the light source device is expanded is achieved.

  In a preferred embodiment of the voyeurism prevention device according to the present invention, a light source device, a projection lens system, and a beam deflecting unit are unitized to provide a plurality of voyeurism prevention units, and the focal length of the projection lens system of each voyeurism prevention unit is set respectively. Each of the voyeurism prevention units projects the interference light toward different positions along the depth direction of the audience space.

In the present invention, since disturbing light that changes temporally or spatially is projected on the video content projected on the screen, even if the video content is voyeurized, the voyeurized video content can withstand viewing. It has deteriorated as much as possible. As a result, voyeurism can be effectively prevented. Further, since the interference light is directly projected from the screen side to the video camera located in the audience space, it is possible to effectively prevent voyeurism using a light source device having a relatively small capacity.
Furthermore, since the voyeurism prevention device of the present invention prevents voyeurism using an existing image display device as it is, it is possible to use an image display device installed in a theater or a movie theater as it is.

  FIG. 1 is a diagram showing an example of a voyeurism prevention device according to the present invention. The video content information output from the video content output device 1 is supplied to the image display device 2 constituted by, for example, RGB three primary color projectors. RGB image lights are emitted from the image display device 2, projected onto the screen 3, and color image content is displayed on the screen 3. The RGB image light is reflected by the screen 3, enters the audience space, and is viewed by the audience. If the audience uses the video camera 4 to capture the video content projected on the screen, the video content projected on the screen is voyeurized.

  The voyeurism prevention apparatus according to the present invention prevents voyeurism by degrading the video content projected on the screen without affecting the viewer who is viewing. In other words, even if the video content projected on the screen is captured by the video camera, if the quality of the voyeurized video content deteriorates to the extent that it cannot be viewed, the economic value of the voyeurized video content will disappear. And voyeurism is effectively prevented. The anti-voyeurism device according to the present invention has a light source device 5 that generates interference light for degrading the quality of video content projected on a screen, and the interference light emitted from the light source device passes through a projection lens system 6. Projected onto the screen 3. A control circuit 7 is connected to the light source 5, and the drive of the light source is controlled by the control circuit 7. The disturbing light projected on the screen 3 is reflected by the screen 3 and scattered toward the audience space. Therefore, the interfering light also enters the video camera 4 during the voyeurism together with the image light of the video content. The control circuit 7 controls the light source 5 so that the amount of projected interference light changes with time.

  FIG. 2 is a graph showing the spectral sensitivity characteristics of the human eye and the spectral sensitivity characteristics of an image sensor used in a general video camera. In FIG. 2, the solid line indicates the spectral sensitivity characteristic of the RGB image sensor, and the alternate long and short dash line indicates the spectral sensitivity characteristic of the human eye. The human eye has an end on the short wavelength side in the visible range near 380 nm, and an end on the long wavelength side in the visible range near 680 nm. On the other hand, in the case of a video camera using three RGB image sensors, generally, the B image sensor has the highest sensitivity around 450 nm, the G image sensor has the highest sensitivity around 550 nm, The image sensor has the highest sensitivity around 650 nm. The R imaging element has sensitivity up to a wavelength region exceeding 800 nm. Therefore, infrared light, near-infrared light, and far-infrared light having a wavelength exceeding 680 nm are not detected by human eyes, but are detected by the video camera 4. Therefore, in the present invention, infrared light having a longer wavelength than the long wavelength end of visible light is used as interference light. Various light sources that emit light having a wavelength longer than the long wavelength end of visible light can be used as a light source device that generates interference light. For example, an LED or a laser diode can be used. Further, a combination of various lamps such as a xenon lamp and a halogen lamp and a band pass filter is also used.

  Even if the interference light is projected on the screen on which the video content is projected, the viewer visually recognizes the normal video content and does not give the viewer a problem. On the other hand, paying attention to the image pickup device of the video camera for voyeurism, the amount of light incident on the image pickup device that picks up the G and B wavelength light does not change even if disturbing light is incident. Is output. On the other hand, in addition to the image light of the video content, a large amount of interference light in the infrared region is also incident on the image sensor that photoelectrically converts R wavelength light. For this reason, an extremely high level luminance signal is output from the image sensor that photoelectrically converts R wavelength light. As a result, the voyeurized video content changes to a strong red image, and a significant color unevenness is formed, resulting in a deteriorated video. Further, when the intensity of the disturbing light changes with time, the video content that has been sneak shot changes significantly into a deteriorated image that cannot withstand viewing. As a result, even if sneak shots are taken, since the sneak shot video has deteriorated so that it cannot be viewed, secondary distribution is prevented.

  As the light source device, for example, an array in which a plurality of LEDs are arranged can be used. In this case, if each LED element is intermittently turned on individually, strong flicker occurs in the video content projected on the screen. Moreover, if the infrared light emitted from each LED element is projected as a spot on the screen by the projection lens system, the video content projected on the screen becomes an image spatially modulated by a strong red spot. . In addition, a single light source can be used as the light source device, and in this case, the light source can radiate disturbing light at a predetermined time interval or at irregular time intervals, thereby deteriorating video content that has been voyeurized.

  FIG. 3 shows the structure of another anti-peeping device according to the present invention. FIG. 3 (A) is a schematic plan view seen from above the screen, and FIG. 3 (B) shows the state of occurrence of interference light. It is a diagrammatic perspective view. In addition, the same code | symbol is attached | subjected and demonstrated to the member same as the member used in FIG. In this example, a laser 10 that emits an infrared laser beam is used as the light source device. The laser beam emitted from the laser 10 is converted into an expanded parallel light beam by the collimator lens 11 and enters the two-dimensional diffraction grating 12. The laser beam is converted into a plurality of sub beams by the two-dimensional diffraction grating 12, and the plurality of sub beams are projected as spots onto the screen 3 via the projection lens system 6. Since each spot on the screen 3 is composed of infrared light, it is not perceived by the viewer but is received by the video camera. As a result, the video content that has been sneak shot is degraded by being spatially modulated by a strong red spot.

  4A and 4B show the structure of another anti-peeping device according to the present invention. FIG. 4A is a schematic plan view seen from above the screen, and FIG. It is a diagrammatic perspective view which shows the incident state to the screen of light. In this example, a combination of an LED array 20 and a reflecting mirror 21 in which a plurality of LED elements that emit infrared light are arranged in the vertical direction is used as a light source device. A line-shaped disturbing beam extending in the vertical direction (corresponding to the vertical direction of the screen) is emitted from the light source device of the LED array 20 and the reflecting mirror 21, and the line-shaped disturbing beam passes through the projection lens system 6. And projected as a line-shaped spot on the screen 3. The LED array 20, the reflecting mirror 21, and the projection lens system 6 are housed in a frame 22 and unitized as a light source unit. The light source unit is disposed on a stage 24 connected to the rotation shaft of the motor 23 as shown in FIG.

  The motor 23 reciprocates over a predetermined angle range. The linear spot projected on the screen by the reciprocating rotation of the motor 23 reciprocates along the horizontal direction of the screen 3, and the video content projected on the screen extends in the vertical direction of the screen. Scanning is performed by a linear spot of infrared light. As a result, the video content voyeurized by the video camera becomes a video deteriorated by a strong red band that runs periodically. In this example, the screen is scanned in the horizontal direction by a line-shaped disturbing beam extending in the vertical direction of the screen. However, the disturbing beam extending in the horizontal direction of the screen is used, and the vertical direction of the screen is used. It is also possible to scan.

  FIG. 5 is a diagram showing the configuration of the anti-peeping device according to the present invention. FIG. 5 (A) is a diagrammatic plan view seen from above the screen, and FIG. 5 (B) is a diagram showing the interference light emitted from the anti-peeping device. It is a diagrammatic perspective view which shows the incident state to a screen. In this example, a laser 30 that emits infrared light is used as the light source device. The laser beam emitted from the laser 30 is converted into an expanded parallel light beam by the collimator lens 31 and enters the one-dimensional diffraction grating 32. The laser beam is converted by the one-dimensional diffraction grating 32 into a plurality of sub beams arranged in a substantially vertical direction (corresponding to the vertical direction of the screen 3). The plurality of sub beams are incident on a polygon mirror (rotating polygon mirror) 33, deflected at high speed along a direction corresponding to the horizontal direction of the screen, and projected onto the screen 3 through the projection lens system 6. A plurality of circular spots arranged in the vertical direction are projected on the screen 3, and these spots travel at a high speed along the horizontal direction. Accordingly, the video content projected on the screen 3 is scanned at a high speed by a plurality of circular spots of infrared light. As a result, the video content that has been voyeurized by the video camera is scanned by a strong red spot that travels at high speed along the horizontal direction of the screen, and deteriorates into a video that cannot be viewed. In this example, the scanning is performed along the horizontal direction of the screen using a plurality of spots. However, it is also possible to scan in the vertical direction of the screen using a plurality of spots arranged along the horizontal direction of the screen. .

  FIG. 6 is a diagram showing a configuration of a voyeurism prevention device according to the present invention. In this example, disturbing light is projected from the screen side toward the audience space, and the disturbing light is periodically projected onto the video camera that is being voyeurized. For example, first to third interference light generation units 40a to 40c are arranged so as to be adjacent to the screen 3, and the interference light is projected from each interference light generation unit toward the audience space. Each interfering light generation unit 40a-40c includes a light source that generates line-shaped infrared light, a deflecting unit that deflects the line-shaped infrared light in a direction perpendicular to the extending direction, and line-shaped infrared light. And a projection lens system for projecting toward the audience space. The focal lengths of the projection lens systems of the respective interference light generating units are different. Interfering light emitted from the interfering light generation units 40a to 40c forms vertically long spots 41a to 41c in the audience space. Since the audience space has a considerably long depth from the screen 3, the audience space is divided into, for example, three areas and is shared by three interference light generation devices. The first disturbing light generator 40a projects the disturbing light toward an area closest to the screen, the second disturbing light generator 40b projects the disturbing light toward an intermediate area in the depth direction, and The interference light generator 3 projects the interference light toward the farthest area from the screen. Each interfering light generator emits line-shaped interfering light extending substantially in the vertical direction, and is periodically deflected in a direction (horizontal direction) perpendicular to the extending direction by the deflecting means. As a method for deflecting interference light, for example, a unit including a light source and a projection lens system can be arranged on a motor, and the motor can be deflected by periodically rotating the motor.

  When the video camera being voyeurized is located in the first area close to the screen, the disturbing light projected from the first disturbing light generator 40a periodically enters the video camera. , A dark red band running along the horizontal direction will result in a degraded image. Similarly, when the video camera under voyeurism is located in the middle area and the farthest area of the audience space, the band-like disturbance light projected from the second and third disturbance light generators 40b and 40c is periodically incident. However, similarly, a dark red band periodically runs along the horizontal direction, resulting in a deteriorated image. It is also possible to use a combination of a laser light source and a diffraction grating as a light source that generates interference light, and a polygon mirror as a deflecting means. In this case, the video content to be voyeurized is a video on which a red spot running at high speed is superimposed, and the video content is deteriorated so as not to endure viewing.

It is a diagram which shows an example of the voyeurism prevention apparatus by this invention. It is a graph which shows the spectral sensitivity characteristic of a viewer's eye, and the spectral sensitivity characteristic of a video camera. It is a figure which shows the voyeurism prevention apparatus by this invention. It is a figure which shows the voyeurism prevention apparatus by this invention. It is a figure which shows the voyeurism prevention apparatus by this invention. It is a figure which shows the voyeurism prevention apparatus by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Video content output device 2 Image display device 3 Screen 4 Video camera 5 Light source device 6 Projection lens system 7 Control diffraction 10 Laser light source 11, 31 Collimator lens 12 Two-dimensional diffraction grating 20 LED array 21 Reflector 22 Frame 23 Motor 24 Stage 30 Laser 31 Collimator lens 32 One-dimensional diffraction grating 33 Polygon mirrors 40a to 40c Interfering light generating units 41a to 41c A vertically long spot

Claims (2)

A voyeurism prevention device that degrades the video content projected on the screen without affecting the viewing audience,
A light source device configured by infrared light having a longer wavelength than the long wavelength end of visible light, and generating interference light that degrades video content;
A diffraction grating that converts the interference light emitted from the light source device into a plurality of sub-beams arranged in a line;
Beam deflecting means for periodically deflecting a plurality of sub-beams emitted from the diffraction grating in a direction perpendicular to the arrangement direction;
A projection lens system for projecting a plurality of sub beams emitted from the beam deflecting means as spots traveling on the screen;
An anti-voyeurism apparatus for scanning video content projected on a screen with a plurality of spots of disturbing light that periodically run along the horizontal or vertical direction of the screen. 2. The anti-voyeurism apparatus according to claim 1, wherein a laser light source that emits a laser beam including an infinite number of speckle patterns is used as the light source device, a polygon mirror is used as the beam deflecting means, and the image projected on the screen. A voyeurism prevention device characterized in that content is scanned at high speed with spots arranged in a line shape including countless speckle patterns.

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