FR3072932A1 - SCREEN DISPLAY DEVICE FIXED TO A PART OF A SYSTEM FOR TRANSPARENCY OF A MASKING MEMBER. - Google Patents

Abstract

A display device (DA) equips a system (VA) comprising a reception area (SC), first acquisition means (MA1) acquiring first images of an outer area located behind a masking element (EM) , and second acquisition means (MA2) acquiring second images of the eyes of a person (CV) present in the reception area (SC). This device (DA) comprises: - a display screen (EA) secured to the masking element (EM), - processing means (MT) estimating a first distance from a masked sub-area to the person (CV) ) by the masking element (EM) as a function of the first (MA1) and second (MA2) acquisition means, second distances separating the outer zone from one point of the system (VA) and a third distance separating said location of the eyes, determining in the first images this sub-area according to the observation direction of the gaze and the first distance, and generating third images of this sub-zone.

Description

® DISPLAY DEVICE WITH A SCREEN FIXED TO A PART OF A SYSTEM FOR MAKING A MASKING ELEMENT TRANSPARENT.

@) A display device (DA) equips a system (VA) comprising a reception space (SC), first acquisition means (MA1) acquiring first images of an external area located behind a masking element ( EM), and second acquisition means (MA2) acquiring second images of the eyes of a person (CV) present in the reception space (SC). This device (DA) includes:

- a display screen (EA) secured to the masking element (EM),

processing means (MT) estimating a first distance from a sub-area masked from the person (CV) by the masking element (EM) as a function of the first (MA1) and second (MA2) acquisition means, second distances separating the external zone from a place in the system (VA) and a third distance separating this place from the eyes, determining in the first images this subzone as a function of the direction of observation of the gaze and of the first distance , and generating third images of this sub-area.

DISPLAY DEVICE WITH A SCREEN ATTACHED TO A PART OF A SYSTEM FOR TRANSPARENCY OF A MASKING ELEMENT

The invention relates to systems which include a reception space for person (s) having in their environment a masking element which can hinder the observation of the environment by a person present in this reception space.

The term “masking element” is understood here to mean an element (possibly structural) installed in an inclined or vertical manner next to a window (or glass) or an open area of a system, and capable of hindering the observation of the environment behind this window or area opened by a person who is present in a reception area (such as a seat). In the non-limiting case of a motor vehicle, the masking element could for example be a window post to which one of the two lateral sides of the windshield is secured, or a middle post (or foot) located between two side windows, or a rear pillar located next to a rear window. In the non-limiting case of an air traffic control tower, the masking element could for example be an upright located between two windows or a building obscuring an area of the runways of an airport. In the non-limiting case of a surveillance space, the masking element could for example be a pillar of a building partially blocking the view of a security guard monitoring an outside area (such as a parking lot or an access gate ).

Certain systems, such as for example certain vehicles, generally of the automobile type, include a seat dedicated to their driver and close to which is installed at least one masking element, such as for example an upright of bay, which masks (or conceals) from the driver a part of the outside environment, which can be dangerous.

To avoid such masking, it has been proposed, in particular in patent document WO 2013/055513, to add to a vehicle a display device comprising a display screen, secured to the internal face of the rack post (neighbor driver's seat), and processing means. The latter are responsible for determining in the first images, representative of at least one external zone located behind the amount of bay and acquired by first on-board acquisition means, a sub-area which is masked by this amount of bay from the driver taking into account the direction of observation of his gaze, determined from second images of at least his head, acquired by second acquisition means installed in the passenger compartment. The processing means are also responsible for generating third images of the determined sub-area so that they are immediately displayed (in "real time") by the display screen.

This type of display device is therefore intended to give the driver the impression that the window pillar is transparent. However, it has a drawback which is likely to disturb the driver. Indeed, it does not take into account the distance between the driver's eyes and the outside area observed by the first acquisition means. However, according to this distance, the portion of the external area which is effectively obscured (or hidden) from the driver by the amount of window is more or less large. Consequently, it frequently happens that the sub-zone determined in the first images is smaller or larger than the portion of the external zone which is effectively obscured (or masked) by the amount of opening.

When the determined sub-area is smaller than the aforementioned portion, it appears enlarged, once displayed, compared to the rest of the outside area which surrounds it and which is directly observed by the driver, and a small hidden part of this outside area is not visible to the driver. When the determined sub-area is larger than the aforementioned portion, it appears, once displayed, reduced in proportion compared to the rest of the outside area which surrounds it and which is directly observed by the driver, and in addition in part redundant with a small unmasked part of this exterior area and therefore observable by the driver. In both cases, there is a lack of continuity between what is observed by the driver directly (outside the display screen) and what is observed by the same driver indirectly (on the display screen) .

The invention therefore aims in particular to improve the situation.

To this end, it proposes in particular a display device, on the one hand, intended to equip a system comprising a reception area for person (s) capable of having in its environment a masking element which can hinder the observation of the environment by a person present in this reception area, first acquisition means acquiring first images representative of at least one external area located behind this masking element, and second acquisition means acquiring second images minus a head of the person, and, on the other hand, comprising processing means determining in these first images a sub-area which is masked by the masking element from the person as a function of a direction of observation of his gaze determined from the second images, and generating third images of this sub-area, and a display screen intended to be secured to a internal face of a part of the system intercepting this direction of observation and responsible for displaying the third images generated.

This display device is characterized by the fact that its processing means:

- estimate a first distance separating from the eyes of the person from the subzone as a function of technical characteristics of the first and second acquisition means and of data representative of second distances separating objects detected in the external zone from a predefined place in the system, and a third distance separating this predefined location from the eyes, and

- determine the sub-area also according to this first estimated distance.

Thanks to the invention, it is now certain that the determined sub-zone precisely corresponds to the portion of the external zone which is effectively masked by the masking element, and therefore an effective continuity of what is observed directly and indirectly is obtained. by the person present in the reception area, which makes the masking element transparent.

The display device according to the invention may include other characteristics which can be taken separately or in combination, and in particular:

- its processing means can use data which is representative of second distances determined by third acquisition means secured to the system;

- as a variant, its processing means can choose the data which are representative of the second distances as a function of a current geographic position of the system and / or of at least one parameter representative of a current dynamic of the system;

its processing means can use technical characteristics comprising at least first and second focal lengths respectively of the first and second acquisition means, a center and dimensions of each first image, and a center and dimensions of each second image, as well that possible distortion parameters of the first and second images;

- its processing means can determine the sub-area also as a function of the first position and orientation of a camera which is one of the first acquisition means with respect to a chosen reference frame attached to the system, of second position and orientation of a camera which is part of the second acquisition means with respect to this chosen frame of reference, and of third position and orientation of the display screen with respect to this chosen frame of reference;

> the first position and orientation, the second position and orientation, and the third position and orientation can be determined by means of at least one test pattern in a preliminary calibration phase, as well as possible distortion parameters of the acquisition means ;

- its display screen can be flexible. For example, this display screen may include a flexible panel, possibly with flexible organic light-emitting diodes, so that its shape can be non-planar, for example in order to match the shape of a rack upright;

- it can include the first means of acquisition and / or the second means of acquisition and / or the third means of acquisition.

The invention also provides a system comprising:

- a reception area for a person capable of having a masking element in their environment which may interfere with the observation of the environment by a person present in this reception area,

- first acquisition means acquiring first images representative of at least one external area located behind this masking element,

- second means of acquisition acquiring second images of at least the eyes of the person, and

- a display device of the type presented above.

For example, this system can include the masking element, and the first acquisition means can be at least partially fixedly attached to an external face of the masking element.

Also for example, this system can be arranged in the form of a vehicle, possibly of the automobile type. In this case, the second acquisition means can be at least partially fixedly secured to a dashboard or to an interior mirror which is oriented towards the person.

Other characteristics and advantages of the invention will appear on examining the detailed description below, and the attached drawings, in which:

- Figure 1 schematically illustrates, in a side view, part of an example of a motor vehicle comprising a driver's seat, located next to an upright and on which a driver sits, and an exemplary embodiment of '' a display device according to the invention,

- Figures 2 and 3 schematically illustrate, in views respectively from the side and from above, the relative position of the head of a driver (seated on a driver's seat) with respect to an indoor camera, an outdoor camera and a screen '' display (secured to a rack post and forming part of a display device according to the invention), and

- Figure 4 illustrates schematically, in a perspective view, the pins associated respectively with the indoor camera, outdoor camera and display screen of Figures 2 and 3, and a calibration target used during a calibration phase.

The object of the invention is in particular to propose a display device DA intended, on the one hand, to equip a VA system comprising a reception space for person (s) SC, suitable for having in its environment a masking element EM may interfere with a person's observation of the environment

CV present in this space of reception SC, and, on the other hand, to make this masking element EM transparent for this person CV.

In what follows, we consider, by way of nonlimiting example, that the VA system is a vehicle of automobile type, such as for example a car. However, the invention is not limited to this type of system. It relates in fact to any type of system comprising at least one reception area for people who may have in their environment a masking element which may interfere with the observation of the environment by a person present in this reception area. Consequently, it concerns in particular vehicles (land, sea (or river) and air), and buildings (in particular air traffic control towers).

In the case of a vehicle VA of the automobile type, the reception space SC is a seat, for example that of the driver CV, and the masking element EM can be an amount of opening to which one of the two sides is secured. side of the windshield, or a center pillar (or foot) located between two side windows, or a rear pillar located next to a rear window.

In the non-limiting case of an air traffic control tower, the reception area SC can be an air traffic controller seat or any other predefined space located inside the air traffic control tower, and the masking element EM could for example be an amount located between two windows or a building obscuring an area of the runways of an airport.

In the non-limiting case of a building, the reception space SC can be a vigilance seat or any other predefined observation space located inside this building, and the masking element EM could for example be a pillar of a building partially blocking the view of a security guard monitoring an outside area (such as a parking lot or an access gate).

In general, an EM masking element is an element (possibly structural) installed in an inclined or vertical manner next to a window (or glass) or an open area of a system, and liable to hinder the observation of the environment behind this window or open area by a person who is present in a reception area SC (such as a seat). Such a masking element EM is possibly part of the VA system. This is particularly the case when this VA system is a vehicle.

There is schematically shown in Figure 1 a non-limiting example of VA system (here a vehicle) comprising, on the one hand, a reception area SC (here a driver seat on which sits a CV person (here a driver) and associated with a steering wheel VV), and, on the other hand, a display device DA according to the invention. In the example illustrated, the seat SC is installed next to a masking element EM (here a left bay upright installed in a front part of a cabin H of the vehicle VA).

The VA system (here a vehicle) illustrated in FIG. 1 also includes a windshield PB secured to the upright of the bay EM and to which is secured an interior mirror RI and / or a dashboard, the first acquisition means MA1, and second MA2 acquisition means.

The first acquisition means MA1 are arranged so as to acquire first images il which are representative of at least one external zone ZE situated behind the masking element EM.

For example, and as illustrated without limitation in FIGS. 1 to 3, these first acquisition means MA1 can be at least partially fixedly attached to the external face of the amount of rack EM. More specifically, and as illustrated in FIGS. 2 and 3, they can, for example, include an external Cext camera of the digital type and fixedly fixed to the external face of the amount of EM bay.

It will be noted that the first acquisition means MA1 may possibly be part of the display device DA. But it is not compulsory. Indeed, they could acquire images of the environment of the VA system (here at least on one of its longitudinal sides) for at least one other device embedded in the VA system, such as for example a device for assisting in the driving in the case of a vehicle.

The second acquisition means MA2 are arranged so as to acquire second images i2 of at least the eyes YC of the person CV (here the driver).

For example, and as illustrated without limitation in Figures 1 to 3, these second acquisition means MA2 can be at least partially fixedly secured to the interior mirror RI which is installed in the passenger compartment while being oriented towards the driver CV. More specifically, and as illustrated in FIGS. 2 and 3, they can, for example, include an internal camera Cint of the digital type and fixedly secured to the interior mirror RI.

Note that the second acquisition means MA2 may possibly be part of the display device DA. But it is not compulsory. In fact, they could acquire images of the interior of the passenger compartment H for at least one other device on board the VA system, such as for example a passenger detection device in the case of a vehicle, or else only images of the face of the person CV for another device embedded in the VA system and responsible for analyzing the eyes YC of this person CV, for example to detect a loss of alertness and / or to ensure a control of the respective positions of the various mirrors in the case of a vehicle.

As illustrated in FIG. 1, a display device DA according to the invention comprises at least processing means MT and a display screen EA.

The display screen EA is intended to be secured to an internal face F1 of a part of the system VA which intercepts the direction of observation do from the gaze of the person CV. It is responsible for displaying third i3 images which are generated by the processing means MT, as will be seen below.

In the example which is described here, the display screen EA is secured to the internal face Fl of the masking element EM, which is oriented towards the inside (here of the passenger compartment H).

Note that this EA display screen can be rigid or flexible. In this latter alternative, it can advantageously follow the shape of a portion of the internal face F1 of the part of the system VA (here the masking element EM). To do this, it can, for example, comprise a flexible panel, possibly with flexible organic light-emitting diodes.

Furthermore, this display screen EA can mask (or cover) either all of this internal face F1 (here of the masking element EM), or part of this internal face F1 (as in the example illustrated without limitation in Figure 1).

The processing means MT are in particular arranged so as to determine in the first images it (determined by the first acquisition means MA1) a subzone SZ of the external zone ZE, which is masked by the masking element EM at the person CV (here the driver), as a function of the direction of observation do of his gaze (defined by his eyes YC), which is determined from the second images i2, and from a first estimated distance d1 which separates this sub - SZ zone of the eyes YC.

It is the processing means MT which estimate this first distance d1 as a function of technical characteristics of the first MA1 and second MA2 acquisition means, of data which are representative of second distances d2 which separate objects detected in the outer zone ZE from a predefined place in the system (here a vehicle) VA, and a third distance d3 which separates this predefined place from the eyes YC.

It will be noted that the display device DA (and for example its processing means MT) can (possibly) be arranged so as to determine the direction of observation do of the gaze of the person CV from the second i2 images.

Any technique known to those skilled in the art can be used to make this determination of the direction of observation do. By way of nonlimiting example, this determination can be made as follows. We can start by detecting the face first, possibly using the so-called "Boost Cascade" method developed by Viola and Jones. Then, one can detect in the face the region of the eyes YC thanks to the anthropometric relationship between the face and the eyes YC. Then, the irises and their centers can be detected in the eyes YC, for example by using the image gradient. Finally, we can reconstruct the irises in three-dimensional space by assuming that their characteristics (for example their rays) are known, then we can consider that the direction of observation do is normal to the irises.

As mentioned above, the processing means MT are also arranged so as to generate third images i3 of the subzone SZ of the external zone ZE which must be displayed by the display screen EA. It will be understood that these third images i3 are defined on the basis of digital data files which define the first images il, since they constitute sub-parts of the latter (he) suitable for display in the format of the display screen. EA.

The first distance d1 separating the eyes YC of the person CV from the external zone ZE observed by the first acquisition means MA1 now being taken into account in the determination of the sub-zone SZ (to be displayed), we are now sure that the latter precisely corresponds to the portion of the outer zone ZE which is effectively obscured (or masked) by the masking element EM. Consequently, there is an effective continuity between what is observed by the CV person directly (outside the EA display screen) and what is observed by this same CV person indirectly (on the EA display screen). (i.e. the SZ subzone)), without enlargement and without reduction, which avoids disturbing the person CV.

In the foregoing, it has been indicated that the display screen EA is secured to the internal face Fl of a part of the system VA which intercepts the direction of observation do. This means that this display screen EA is placed in the system VA between the eyes YC of the person CV and the masking element EM which masks the subzone ZS. Here, it is the masking element EM (left bay upright) which intercepts the direction of observation do.

The determination of the data representative of the second distances d2 (separating objects detected in the external zone ZE from a predefined location of the VA system) can be done in at least two ways.

In a first way, these data representative of second distances d2 can be determined by third acquisition means MA3 which are secured to the system VA, and used by the processing means MT.

These third MA3 acquisition means can, for example, comprise at least one scanning laser (or three-dimensional range finder (or 3D)) or at least one radar or lidar or at least one ultrasound sensor or at least one 3D camera or stereoscopic cameras. When the VA system is a vehicle, the third MA3 acquisition means can be at least partially installed on the longitudinal side of this VA vehicle next to which the CV driver sits. Thus, they can be at least partially installed next to the Cext external camera on the external face of the EM bay upright or on the exterior mirror placed next to the latter (EM).

The predefined location of the VA system can, for example, be the place where the element of the third acquisition means MA3 is installed, which detects the objects present in the external zone ZE and deduces the second distances d2, or else a predefined place whose distance to the aforementioned element is known. In the example illustrated without limitation in FIG. 2, it is considered that the predefined location is the place where the first acquisition means MA1 are installed (we therefore have here d1 = d2 + d3 by way of example).

It will be noted that the third acquisition means MA3 may possibly be part of the display device DA. But it is not compulsory. Indeed, they could acquire data representative of the environment of the VA system (at least on one of its longitudinal sides when it is a vehicle) for at least one other device on board the VA system, such as for example a driving assistance device.

In a second way applicable to systems that can move, the processing means MT can choose the data that is representative of the second distances d2 as a function of the current geographic position of the VA system and / or of at least one parameter representative of the current dynamics of the VA system, such as its speed or acceleration. As a purely illustrative example, when the vehicle VA is in town, the processing means MT can choose second distances d2 equal to 5 meters.

It will be noted that the processing means MT can, for example, use technical characteristics comprising at least first and second focal lengths respectively of the first MA1 and second MA2 acquisition means, the center and the dimensions of each first image il, and the center and dimensions of each second i2 image, as well as possible distortion parameters of the first it and second i2 images.

For example, you can use a Cext outdoor camera with a 1 / 1.2 ”or 10.67 mm x 8 mm sensor and a focal length of 6 mm, a Cint indoor camera with a 1/2” or 6.4 mm x 4 sensor , 8 mm and a focal length of 4 mm, and an EA display screen of 498 mm x 121 mm.

The center and dimensions of a first il or second i2 image can be determined during a preliminary factory calibration phase.

It will also be noted that the processing means MT can, for example, determine the subzone SZ also as a function of the first position and orientation of the outdoor camera Cext (forming part of the first acquisition means MA1) relative to a chosen frame of reference. attached to the VA system, second position and orientation of the indoor camera Cint (part of the second acquisition means MA2) relative to this chosen reference frame, and third position and orientation of the display screen EA with respect to this repository chosen.

For example, the first position and orientation, the second position and orientation, and the third position and orientation, as well as possibly the focal lengths and dimensions and center of the images il and i2 can be determined by means of at least one calibration test pattern. MC in a preliminary calibration phase.

To do this, it is possible, as illustrated diagrammatically in FIG. 4, to associate reference frames respectively with the Cext outdoor camera, Cint indoor camera and EA display screen. In this figure 4, the frame of reference (Xcext, Ycext, Zcext) is associated with the outdoor camera Cext, the frame of reference (Xcint, Yen, Zcint) is associated with the indoor camera Cint, the frame of reference S (Xs, Ys, Zs) is associated with the display screen EA, and the reference frame W (Xw, Yw, Zw) is associated with the calibration target MC whose position is precisely known with respect to the chosen reference frame attached to the VA system. As an example, this chosen repository linked to the VA system can be the one associated with the EA display screen.

During the calibration phase, the MC calibration target can be placed in several different positions (for example ten), in order to acquire with each Cext, Cint camera images of this MC calibration target. Numerous reference points of the MC calibration target can be detected in each image and then used as three-dimensional information to estimate the focal length, the center of the image, the dimensions of the image, the position and the disorientation (or rotation). between the camera and the MC calibration target (in each position), and any distortion coefficients.

For example, the MC calibration target can be exposed in the field of the Cext outdoor camera to calculate the position and the orientation of the latter in the W reference associated with this MC calibration target. The position is defined by a translation T and the orientation is defined by a rotation R. As this calibration target MC is not initially in the field of the indoor camera Cint, the position and orientation of the latter are calculated in the frame W associated with this calibration target MC using a mirror Ml. In other words, the indoor camera Cint observes the calibration pattern MC reflected by the mirror M1. Then, the relative position and orientation between the outdoor camera Cext and indoor camera Cint can be deduced from their respective position and orientation relative to the frame of reference W associated with the calibration target MC by using, for example, the following equations:

R (Cint) Cext = R (Cint) w * R (W) cext and

T (Cint) Cext = T (Cint) w - (R (Cint) Cext * T (Cext) w.

In these two equations R (Cint) cext is the rotation of Cint relative to the frame of reference associated with Cext, R (Cint) w is the rotation of Cint relative to the frame of reference W associated with the calibration target MC, R (W) cext is the rotation of the calibration target MC relative to the reference frame associated with Cext, T (Cint) cext is the translation of Cint relative to the reference frame associated with Cext, T (Cint) w is the translation of Cint relative to the reference frame W associated with the calibration target MC, and T (Cext) w is the translation of Cext with respect to the reference frame W associated with the calibration target MC.

It will also be noted that the processing means MT can be produced in the form of software modules (or computer or even "software"), or else a combination of electronic circuits (or "hardware") and software modules. Consequently, they can be part of a CA computer of the VA system (as illustrated in FIG. 1) or else constitute a computer dedicated to the determination and generation of the third i3 images.

It will also be noted that when the display screen EA is flexible and conforms to the shape of a part of the internal face F1 (here of the masking element EM), it may have at least one curvature. In this case, the third i3 5 images that it displays are preferably generated by taking into account each curvature so as not to introduce deformation.

It will also be noted that in order to avoid too frequent refreshment of the third images i3, potentially disturbing for the seated person CV, the processing means MT can perform filtering so as to generate the third images i3 according to a period which is more great that the period of acquisition of the first images there.

It will also be noted that when the VA system is a vehicle, it may be necessary, when it moves at a speed greater than a threshold, to take account of the time difference between the instants of acquisition of the first 15 images by the first acquisition means MA1 and the instants for displaying the third images i3 on the display screen EA. For this purpose, image processing can be carried out taking into account the speed of the vehicle VA. Such treatments are well known to those skilled in the art.

Claims (10)

1. Display device (DA) for a system (VA) comprising i) a reception space for person (s) (SC) capable of having in its environment a masking element (EM) which may interfere with the observation of the environment by a person present in said reception space (SC), ii) first acquisition means (MA1) acquiring first images representative of at least one external area (ZE) located behind said masking element (EM) , and iii) second acquisition means (MA2) acquiring second images of at least the eyes of said person (CV), said device (DA) comprising a) processing means (MT) determining in said first images a subzone (SZ) masked by said masking element (EM) from said person (CV) as a function of a direction of observation of his gaze determined from said second images, and generating third images of this subzone (SZ ), and b) a display screen display (EA) intended to be secured to an internal face (Fl) of a part of said system (VA) intercepting said direction of observation and responsible for displaying said third generated images, characterized in that said processing means (MT ) estimate a first distance separating said sub-area (SZ) from the eyes of said person (CV) as a function of technical characteristics of said first (MA1) and second (MA2) acquisition means and data representative of second distances separating objects detected in said outer area (ZE) of a predefined location of said system (VA) and of a third distance separating said predefined location from said eyes, and determine said sub-area (SZ) further depending on said first estimated distance. 2. Device according to claim 1, characterized in that said processing means (MT) use data representative of second distances determined by third acquisition means (MA3) secured to said system (VA). 3. Device according to claim 1, characterized in that said processing means (MT) choose said data representative of second distances as a function of a current geographic position of said system (VA) and / or of at least one representative parameter of a dynamic in progress of said system (VA). 4. Device according to one of claims 1 to 3, characterized in that said processing means (MT) use technical characteristics comprising at least first and second focal lengths respectively of said first (MA1) and second (MA2) means of acquisition, a center and dimensions of each first image, and a center and dimensions of each second image. 5. Device according to one of claims 1 to 4, characterized in that said processing means (MT) determine said sub-area (SZ) further depending on first position and orientation of a camera (Cext), making part of said first acquisition means (MA1), relative to a chosen frame of reference attached to said system (VA), of second position and orientation of a camera (Cint), forming part of said second acquisition means (MA2), by relative to this chosen reference frame, and third position and orientation of said display screen (EA) relative to this chosen reference frame. 6. Device according to claim 5, characterized in that said first position and orientation, said second position and orientation, and said third position and orientation are determined by means of at least one test pattern (MC) in a preliminary calibration phase. 7. Device according to one of claims 1 to 6, characterized in that said display screen (EA) is of the flexible type. 8. System (VA) comprising i) a reception space for person (s) (SC) suitable for having in its environment a masking element (EM) which may interfere with the observation of the environment by a person present in said space reception (SC), ii) first acquisition means (MA1) acquiring first images representative of at least one external area (ZE) located behind said masking element (EM), and iii) second means of acquisition (MA2) acquiring second images of at least the eyes of said person (CV), characterized in that it further comprises a display device (DA) according to one of claims 1 to 7. 9. System according to claim 8, characterized in that it comprises said masking element (EM), and in that said first acquisition means (MA1) are at least partially fixedly secured to an external face of said masking element ( EM). 5 10. System according to claim 8 or 9, characterized in that it is arranged in the form of a vehicle.