IT202000009772A1 - IMPROVED EQUIPMENT FOR NAVIGATION OF VOLUMETRIC DATA - Google Patents

Description

DESCRIPTION

of the invention entitled:

"Improved apparatus for navigating volumetric data?

The present invention relates to an apparatus for navigating volumetric data, preferably of a three-dimensional body.

STATE OF ART

Machines are currently known for the acquisition of Computerized Axial Tomography (TAC) or Nuclear Magnetic Resonance (NMR) which allow to obtain information on the three-dimensional shape of a body. In particular, this obtained by capturing a plurality? of successive sections, also called ?slices?, which are memorized, together with the information on the position of each slice on the third axis, which generally ? perpendicular to the plane of the slice itself.

? otherwise? the use of three-dimensional images is known which, for example, concern three-dimensional models used for 3D printing, or models that are generated by computer for the visualization of scientific data, such as geological or astronomical models, or of physical and/or chemical systems , or models that are obtained through aerodynamic or hydrodynamic analyzes following experiments inside wind or water tunnels.

To allow the representation of representative images of three-dimensional models, ? notes the technique of projecting the images themselves onto two-dimensional surfaces. For example, images can be projected onto non-interactive surfaces such as sheets of paper or walls.

However, these known solutions are not fully satisfactory since the display surface is static and allows little interaction with the projected image. Therefore, any changes to the projected image can only be made by acting on the projector, manually or by the user using devices. Furthermore, in this case, it becomes complex to ?navigate? the depth?, as ? necessary to act on the projector, or possibly on the device that controls it, making cos? the operation is not very intuitive and difficult to carry out.

? he also knows the solution of displaying the representative images of three-dimensional models on corresponding interactive displays, such as the screen of a computer, a television or other devices, such as a smartphone. However, not even these solutions are fully satisfactory, since generally, in order to reconstruct the concept of depth, the visualization of the images takes place by ?scrolling? between a series of two-dimensional images and what? it is not optimal as years of training are needed to allow the human brain to reconstruct a three-dimensional model starting from a series of two-dimensional images (slices). Furthermore, in these cases, known the problem of the scale, and cio? the lack of correspondence between the dimensions of the images and the real dimensions of the object, which is particularly relevant in the case of medical type images, such as CAT scans, or MRIs, above all for the third dimension, ie? the one perpendicular to the development of each slice, and therefore perpendicular to the representation surface of the slice itself. In fact, it is very complicated to visualize the space traveled in passing from one image to the next.

Further ? note the possibility to display three-dimensional models elaborated by a process (such as a computer) on interactive surfaces, such as the computer screen itself, and to rotate or move them using specific commands.

However, even this system is not fully satisfactory since, in the same way as the representation of a plurality? of two-dimensional images (slices), does not allow you to get a clear idea of the dimensions and/or proportions of the model itself.

Purpose of the invention? that of proposing an apparatus which allows three-dimensional bodies to be displayed on two-dimensional surfaces, overcoming the aforementioned drawbacks foreseen in traditional solutions.

Another purpose of the invention? that of proposing an apparatus that allows for the intuitive visualization of three-dimensional bodies.

Another purpose of the invention? that of proposing an apparatus that allows three-dimensional bodies to be visualized starting from a series of two-dimensional images (?slices?).

Another purpose of the invention? that of proposing an apparatus that is easy and quick to use.

Another purpose of the invention? that of proposing an apparatus that allows to visualize three-dimensional bodies, and in particular bodies of medical images such as CAT scans or magnetic resonance imaging, on a 1:1 scale.

Another purpose of the invention? that of proposing an apparatus which allows the visualization of three-dimensional bodies on curved surfaces.

Another purpose of the invention? that of proposing an apparatus which allows to visualize portions of three-dimensional bodies corresponding to different portions of their volume.

Another purpose of the invention? that of proposing an apparatus which allows the displayed portion of a three-dimensional body to be modified in a simple, rapid and intuitive way.

Another purpose of the invention? that of proposing an apparatus that can be used for the training of medical personnel.

Another purpose of the invention? that of proposing an apparatus that can be used by medical personnel in the discussion phase with the patient and/or in the preoperative preparation phase and/or in the operative phase.

Another purpose of the invention? that of proposing an apparatus that allows to visualize in a simple, rapid and intuitive way the 3D models to be printed.

Another purpose of the invention? that of proposing an apparatus that can be used in spaces of various sizes.

Another purpose of the invention? that of proposing an apparatus that can be used in environments with different lighting conditions.

Another purpose of the invention? that of proposing an apparatus that is an improvement and/or alternative to traditional solutions.

Another purpose of the invention? that of proposing an apparatus that can be implemented simply, quickly and with low costs.

All these objects, both individually and in any combination thereof, and others which will result from the following description are achieved, according to the invention, with an apparatus having the characteristics indicated in claim 1.

The present invention is hereinafter further clarified in some of its preferred embodiments shown for purely exemplifying and non-limiting purposes with reference to the attached drawings, in which:

Figure 1 shows a schematic view of the apparatus according to the invention, Figure 2 shows a schematic view of the apparatus according to the invention in a second embodiment,

figure 3 shows a flow chart of the operation of the apparatus according to the invention in a first embodiment,

figure 4 shows a flow chart of the operation of the apparatus according to the invention in a second embodiment,

figure 5 shows a perspective view of the three-dimensional object to be represented and the corresponding two-dimensional images which represent it,

Figure 6 shows a schematic perspective view of the process of representing an image according to the invention,

figure 7 shows a front view of the projected image of figure 6,

Figure 8 shows a schematic perspective view of the acquisition and detection process of a display surface,

figure 9 shows a schematic front view of the display surface of figure 8 in the reference system of the distance detector, with the different heights highlighted,

figure 10 shows it in the absolute reference system W,

figure 11 schematically shows the process of intersection between the three-dimensional object and the display surface, and

Figure 12 shows a schematic perspective view of the process of displaying the image.

The present invention refers to an apparatus for browsing three-dimensional data, and in particular a volumetric dataset (V) which represents/describes a three-dimensional body.

In particular, the browsing of a volumetric dataset comprises the display on a display surface 20 of images 12 created and obtained from volumetric data which can be encoded in the form of a preferably ordered succession of two-dimensional images, as shown in figure 5, or from a three-dimensional model that pu? be described/represented for example by point cloud, polygonal mesh or voxel dataset or other known methods used for the representation of a three-dimensional body or structure.

Preferably, for example, a three-dimensional body or structure can be described/defined by the succession (stack) of images (?slices?), aligned and spaced along a direction (corresponding to the depth?), such as for example the images that are acquired during a CT scan or during an MRI. In particular, for ?depth?? here we mean preferably the direction that ? perpendicular to the plane on which the two-dimensional images develop, and ? generally an information contained as metadata in the images themselves. In essence, therefore, each slice ? an image of a slice of the body or three-dimensional structure of a certain thickness and, therefore, by stacking the slices in an orderly manner it is possible to construct a representative volumetric dataset of said three-dimensional body or structure.

As can be seen from the figures, the apparatus according to the invention, indicated as a whole with the reference number 100, comprises:

- at least one distance detector 2,

- at least one viewer 4, e

- a?unit? control and processing 6.

Conveniently, the apparatus 100 can? understand a device 1, 1? and a display area 20, which can? be external to the device 1 (cf. embodiment of fig. 1) or can? be integrated in device 1? (cf. embodiment of Fig. 2 ).

Conveniently, in the embodiment of fig.1, the device 1, 1? of the apparatus 100 in turn comprises said at least one distance detector 2, said at least one display 4 and a unit? of control and processing 6. Conveniently, in this case, the display 4 comprises a projector 22 configured to project the images onto the display surface 20, which is? structurally independent, separate and external to the viewer 4.

Advantageously, in said first embodiment shown in figure 1, said at least one distance detector 2 and said at least one display 4 can be positioned inside the same container 8. Preferably, inside the same container 8, it can be be otherwise? housed also the? unit? control and processing 6.

In a second embodiment shown in figure 2, the device 1? of the apparatus 100 comprises said at least one display 4 and a unit? of control and processing 6. Conveniently, in this case, the display 4 comprises and/or ? associated with a visual display 21 for displaying/implementing digital images. Conveniently, in this case, the viewing display 21 defines the viewing surface 20 of the images and, therefore, in this case, the viewing surface 20 belongs to and ? integrated in viewer 4, and then in device 1?. Advantageously, in this second embodiment, the device 1? ? that for example can? be defined by a tablet ? can? understand the unit? of control and elaboration 6 and the visualization display 21 defining the visualizer 4. In particular, in this case, the unit? of control and elaboration 6 and the visualization display 21 are mutually associated and, more? in detail, they can be contained in a container 8?. Conveniently, in a version not shown, the device 1? does it include a visualization display 21 (for example defined by a monitor) which ? external and connected to the unit? of control and processing 6 (which is defined for example by a traditional computer/processor).

Preferably, in this embodiment of the apparatus 100, the distance detector 2 is external and/or separate from said device 1? including the? unit? of control and processing 6 and the visualization display 21. However, in an embodiment not shown here, could the distance detector 2 be provided inside the same device 1? which includes the? unit? of control and processing 6 and the visualization display 21.

The distance finder

Advantageously, the distance detector 2 ? configured to measure the distance of a point, fixed or mobile, of space, with respect to a reference system, preferably corresponding to the reference system of the distance detector itself. Conveniently, the distance finder 2 pu? comprising at least one conventional distance sensor, for example optical or ultrasound.

Preferably, the distance finder 2 ? configured to measure the distance of the display surface 20 with respect to a reference system, preferably corresponding to the reference system of the distance detector itself

Preferably, the distance finder 2 can? be of the optical type, that is? configured to send an electromagnetic wave onto a surface 20 to be measured and detect its reflection.

Conveniently, the distance finder 2 pu? be configured to send a flash of light, preferably infrared, and therefore invisible to the human eye, or alternatively a flash of visible or ultraviolet light or in the radio wave frequency range, and to measure the time between the? emission of the flash and the arrival of the photons reflected by the surface 20, thus determining the distance traveled by the photon itself.

Appropriately, starting from these data ? possible for the detector of distance 2 or for the unit? of control 6 to reconstruct the morphology of the surface 20. Conveniently, the detector of distance 2 pu? be a time of flight device (?Time of Flight?).

Preferably, the distance finder camera 2 can? have a? high resolution, in order to obtain a description pi? accurate surface 20. For example, pu? have a resolution of at least 512x424 pixels, and preferably a resolution of 640x480 pixels.

Conveniently, the distance finder 2 pu? be configured to send through a suitable light source a pattern such as a grid, or a chessboard, or any other regular or irregular pattern, or a single line of light, preferably infrared, but alternatively visible or ultraviolet or even a wave radio, and detect the pattern reflected by the surface 20 by one or more? cameras, and preferably at least two cameras positioned in separate and distinct positions with respect to each other, and with respect to to the light source. Conveniently, the pattern detected by said at least one video camera is deformed with respect to that sent by the light source due to the irregularity of the surface 20 and of the parallax and, on the basis of the deformations detected, the detector of distance 2 and/or the unit? of control and processing 6 can be configured to reconstruct the morphology of the surface 20. Conveniently, the distance detector 2 can? be a structured light 3D scanner.

Conveniently, the detector of the distance 2 pu? use a sound impulse ? i.e. a pressure wave - resulting substantially equivalent to a sonar.

Conveniently, the distance finder 2 pu? be a stereographic camera, and understand what? at least two video cameras configured to obtain two images of the same surface 20 from two different angles, from which ? possible to reconstruct the morphology of the surface itself.

Advantageously the resolution in depth? of the detector of distance 2 pu? be greater than 1 mm, and preferably of a few micrometres, for example 10 micrometres, and an angular resolution of about 0.0015 radians in order to obtain an accurate representation of the images 4 which will subsequently be projected.

Preferably the distance finder 2 pu? be configured - i.e. particular can? include configured optics ? to detect the morphology of surfaces at a distance that pu? reach about ten metres, in order to allow the use of the device 1, 1? in large rooms. The distance finder ? otherwise? configured - and in particular pu? include configured optics ? to detect the morphology of surfaces at a distance of up to a few tens of centimetres, for example 0.5 m, in order to be able to operate even in substantially narrow environments.

Advantageously, the distance detector 2 can? have an acquisition frequency of at least 15 FPS, in order to guarantee a real-time measurement of the surface 20 which is more? faster than the frequency of perception of the human eye. Preferably, the distance finder 2 can? have a capture rate of at least 30 FPS, and even more? preferably at least 60 FPS in order to ensure that the surface 20 is measured at a frequency which allows the eye of a possible user to view the images 12 displayed on the surface itself as a fluid movement.

Conveniently, said distance detector 2 can? be connected with said unit? control and processing 6 in order to send and receive data and/or information. For example, the link can be made using cables or wireless connections, such as Wi-Fi and/or Bluetooth or other.

Advantageously, the distance detector 2 and/or the unit? of control and elaboration 6 can be configured to elaborate a cloud of points, the cio? a set of points characterized by their position in a coordinate system. Conveniently, said points are selected in order to accurately represent the display surface 20.

Advantageously, the distance detector 2 and/or the unit? control and processing 6 can be configured to process a polygonal mesh, the cio? a set of polygons, defined on the basis of the position of their vertices and the adjacency with the other polygons that make up the mesh itself. Conveniently, said polygonal mesh ? processed in order to accurately represent the display surface 20.

Advantageously, the distance detector 2 and/or the unit? of control and processing 6 can be configured in order to modify the coordinate system in which ? described the display surface 20. For example, pu? be configured to switch from a description of the display surface 20 in the coordinate system of the distance detector 2 to one in which said surface ? described in the viewer 4 coordinate system or in an absolute coordinate system, and cio? which does not depend on the position of distance finder 2 or viewer 4.

Preferably, particularly in the first embodiment of the apparatus 100, the distance detector 2 can be compact in order to reduce the overall dimensions of the device 1 and in particular of the container 8 in which said detector can advantageously be accommodated.

Conveniently, as mentioned, in the embodiment shown in figure 2, the distance detector 2 can preferably be external to the display device 21, and configured to detect the position of the display surface 20, and therefore of the display 21. Conveniently, in this second embodiment, the distance detector 2 can? be connected with the device 1?, and in particular with the unit? of control and processing 6, through wired or wireless connections, such as Wi-Fi, Bluetooth or other.

Conveniently, the apparatus 100 can? understand a plurality of detectors of depth? 2 to detect cos? in a more complete and precise the display surface 20. Conveniently, can the distance detectors 2 be configured ? i.e. positioned and directed ? in order to fully detect the display surface 20, and in particular in correspondence with any reliefs, valleys, or undercut portions, how will it be? more clear later.

The viewer

Conveniently, viewer 4 ? configured to display and/or implement an image 12 on said display surface 20.

In particular, viewer 4 can? preferably be configured to project two-dimensional images (cf. fig. 1). Conveniently, viewer 4 can? be a projector 22.

Advantageously, the projector 22 can be configured - and in particular pu? include configured optics ? to have a focusing distance between a few tens of cm and a few meters, in order to be used in rooms/spaces of different sizes. Preferably, the focusing distances of the projector 22 substantially correspond to the distances of optimal use of the distance detector 2, and in particular to the distances at which the distance detector 2 is configured to sense the distance of a display surface 20.

Fittingly, the projector 22 ? configured - i.e. in particular can? include configured optics? to have a? large depth? of field, preferably at least substantially similar or equal to the depth? represented by the set of images Vn to be represented, and therefore substantially at least corresponding to the dimension of the three-dimensional body 18 to be displayed.

Conveniently, viewer 4 can? be configured to have? high brightness?, preferably greater than 800 lumens, and even more? preferably above 1000 lumens. Preferably the viewer 4 pu? be configured to project and/or implement high resolution images on the display, preferably in full HD (for example 1920x1080 pixels, or any other high definition, depending on the aspect ratio of the image to be displayed). Conveniently, viewer 4 can? be configured to project and/or implement color or black and white images on the display, and preferably pu? be configured to project color images.

Conveniently, projector 22 can? have adjustable focus. Conveniently, projector 22 can? have the adjustable projection trunk, and in particular pu? its orientation in space can be adjusted, in order to allow projection onto projection surfaces 20 which are in different positions.

Advantageously, the device 1 can understand a plurality of (i.e. at least two) projectors 22, and preferably three projectors 22. Advantageously, the projectors 22 can be positioned substantially separated from each other and, preferably, can be configured to project images towards the same display surface 20; There? allows to obtain a complete projection of the image 12 to be projected whatever the morphology of the display surface 20.

In a further embodiment, illustrated for example in figure 2, the viewer 4 can? be constituted by the visualization display 21, which preferably can? be the display of a monitor and/or any electronic device, preferably portable, such as a tablet or smartphone.

Preferably, said display pu? be LED, liquid crystal, or OLED.

Advantageously, the visualization display 21 can be high definition, for example pu? have a maximum resolution of 1920x1080 pixels or higher.

The unit control and processing

The unit control and processing 6 ? electronically connected via cable and/or via wireless (for example via Wi-Fi, Bluetooth, or other) with the viewer 4 and with the distance detector 2.

The unit 6 pu? preferably be positioned inside, or even outside, a container 8 or 8? provided with said display 4 and/or said distance detector 2. In particular, the unit? control and processing 6 pu? be positioned inside the container 8 or 8? provided with said display 4 and/or said distance detector 2, or can? be external but connected to it, and in particular connected to the display 4 and to the distance detector 2 so as to be able to receive and/or send appropriate information and/or data and/or commands from/to the display 4 and/or detector 2.

Preferably in the embodiment, illustrated in figure 1, in which said unit? of control and processing 6 and said viewer 4 are positioned inside the container 8, the connection between these viewer can? be made using cables. In the embodiment, illustrated in figure 2, in which said viewer 4 comprises the display 21 of a device, preferably portable and integrated, the unit? control and processing 6 pu? be defined by the processor of said device, and therefore be connected to said display 4 by means of electrical connections such as cables or conductive tracks integrated in the device itself. When the viewer 4 includes the display 21 of an external monitor, the unit? control and processing 6 pu? be defined by the processor of a dedicated computer, and then be connected to said display 4 by means of cable or wireless connections.

Conveniently, the unit? control and processing system 6 comprises at least one processor (for example a microprocessor or a CPU), preferably a high-performance processor for processing the data and/or information received. Conveniently, the unit? of control and elaboration 6 comprises at least one?unit? of memorization, what ? configured to memorize the images to be displayed, the data and/or information coming from the distance detector 2 and/or other appropriate information.

Preferably, the unit? control and processing 6 also includes? a GPU that ? configured to process the images 12 to be represented coming from and/or acquired by means of an image acquisition device 14.

Advantageously, the unit? control and processing 6 pu? be configured to process the images 12 to be represented and send them to the viewer 4 and, likewise, to receive and process the data detected by the distance detector 2. Preferably, the unit? control and processing 6 pu? be configured to carry out these operations in real time. Advantageously, in particular, the unit? control and processing 6 pu? be configured to process the data obtained from the distance detector 2 in real time, and consequently process the images 12 to be represented by the viewer 4. Advantageously, the unit? control and processing 6 pu? be a computer, and preferably ? a high performance computer.

The image capture device

Conveniently, the unit? control and processing 6 pu? be configured to be connected to one or more? image acquisition devices 14 and/or pu? receive ? for transfer via wireless or cable, or on a traditional external memory medium ? data and/or images 12 to display. Conveniently, said image acquisition device 14 can be configured to acquire one or more? 12 images to be represented and related to a three-dimensional body.

For example, said image acquisition device 14 can be a CT or MRI device. Other examples of data to display include:

- data generated by software, especially 3D design software, which can, for example, be used for 3D printing,

- data relating to three-dimensional bodies to be used for example for the representation of physical or chemical or geological phenomena,

- data acquired inside a wind tunnel or water tunnel, and therefore be related to the fluid dynamic flows on the surface of a three-dimensional body.

Advantageously, the unit? control and processing 6 pu? be configured to autonomously reconstruct, starting from the collected images and any metadata, a three-dimensional object substantially corresponding to the object detected by the image acquisition device 14. Conveniently, the image acquisition device 14 can? be configured to send directly to the unit? of control 6 a three-dimensional modeling of the three-dimensional body detected and, possibly, said modeling can? also be changeable over time.

The display surface

Conveniently, the apparatus 100 according to the invention comprises a display surface 20 which, as mentioned, can be integrated or external with respect to the display 4. Conveniently, the display surface 20 can? be of any type, and in particular pu? be mobile, in the sense that pu? be easily translated and/or rotated in space, in particular by a user of the apparatus 100. Furthermore, advantageously, the display surface 20 can? be configured to be deformed, assuming a complex morphology, including bends, curves, reliefs and depressions when seen from the perspective of, for example, the distance detector 2 and/or the projector 22 which can? define the viewer 4.

Preferably the display surface 20 can? be - at least partially - transparent and/or translucent, that is? a fraction of the incident light (i.e. the light coming from said at least one projector 22viewer) can? be reflected while a part pu? be transmitted through the display surface itself. This allows substantially to take advantage of two display surfaces of the image, corresponding respectively to the display surface 20 itself ? i.e. the surface of the laminar element which substantially faces the display projector 22? and the rear surface of the laminar element which defines the display surface 20. Conveniently, for this purpose, preferably, the display surface 20 can? be substantially thin, i.e. be less than a few millimeters thick.

Conveniently, particularly in one embodiment (cf. for example Fig. 1), the element which substantially defines/constitutes the display surface 20 can? be an element, preferably laminar, such as a sheet, for example of paper, in which case the display surface 20 is represented by the surface of the sheet facing said projector 22, and the viewing surfaces substantially correspond to the two opposite faces of the sheet itself. Conveniently, for example, the display surface 20 can be defined by the user's own hand. Conveniently, for example, the display surface 20 can be defined by a solid object, such as a wall. Advantageously, the display surface 20 can be provided with at least one symbol or other visual characterization that serves as a reference.

Conveniently, in the embodiment illustrated in figure 2, said display surface 20 can be defined by the visualization display 21 and therefore be integrated in the visualization 4 which allows the images 12 to be represented, preferably in real time. visualization Preferably, the visualization display 21 (and therefore the visualization surface 20) can? be mobile and / or portable, and pu? be integrated to the? unit? 6 and/or connected externally to the latter.

Conveniently, the viewing display 21 - which defines the viewing surface 20 ? can? be moved in space by the user/operator, ie? can? be moved so as to change its position and/or orientation in space.

Preferably furthermore, the visualization display 21 can be substantially laminar, that is? its thickness? much smaller than the other two sizes.

Advantageously, also in this embodiment, the display surface 20 can have a variable form, and cio? can? be deformed by the user.

Conveniently, then, in both embodiments, ? Is it possible to modify the position and/or the orientation and/or the conformation of the display surface 20, thus allowing? to navigate between different images of a three-dimensional body, how will it be? more clear later.

Also like this ? is it possible to select in a more the representative image (?slice?) of said three-dimensional body 16 to be displayed on said display surface 20 is accurate.

Modeling of the three-dimensional body to be represented (starting data)

Conveniently, the apparatus 100 ? configured to receive in input the volumetric data which model/describe a three-dimensional body 16. Conveniently, said volumetric data are made available to the unit? control and processing system 6 of the apparatus 100 in the form of at least one computer file.

In particular, said three-dimensional body 16 can be modelled/described in different ways.

Advantageously, for example, as shown in figure 5, a three-dimensional body 16 can be defined and described by a plurality? of images (slices) 18. Conveniently, the? order in which the images (slices) must be analyzed pu? be contained in the same file in which the data which substantially constitute the image (slice) itself are contained, or they can be contained in a file external to the image (slice), which can? contain substantially all the metadata, the cio? the data necessary for the reconstruction of the three-dimensional body 16 starting from the slices 18.

Conveniently, a three-dimensional body 16 can? be described/defined by a lattice (polygonal mesh) composed of vertices, edges and faces of polygons, and preferably triangles, with different dimensions, shapes, and three-dimensional orientation. Conveniently, said polygons can substantially tessellate a surface which corresponds to the three-dimensional object 16 to be acquired. Conveniently, each polygon pu? be defined by the three-dimensional position of its vertices and its color. For example each polygon, pu? present a single color or a shade, or can you? be applied a certain texture, or can? be transparent. Conveniently, the polygons can be structured and positioned in order to accurately describe and/or provide a satisfactory approximation of the three-dimensional object to be described.

Conveniently, the three-dimensional body 16 can be described/defined by a plurality? of three-dimensional objects, such as polyhedrons or solids with a curved surface, which substantially can define voxels. Conveniently, each voxel pu? be defined by its position in space (and in particular that of its vertices), and by its color. For example, each voxel can? present a single color or a shade, or can you? be applied a certain texture, or can? be transparent.

Conveniently, the three-dimensional body 16 can be static or can? be dynamic, that is? vary over time. Conveniently, in this case there are a plurality? of images (slices) 18 for each instant of the temporal evolution of the three-dimensional object 16. Conveniently, in the case of a three-dimensional body 16 represented by a polygonal mesh, this can? be animated according to traditional methods used in the animation of 3D models. Conveniently, in the case of a three-dimensional body 16 represented by a three-dimensional image composed of voxels, a plurality of of three-dimensional images, each substantially corresponding to a frame describing an instant of the temporal evolution of the three-dimensional body, or these can be animated according to traditional methods used in the animation of 3D models.

Conveniently, the temporal evolution of the three-dimensional body 16 pu? be recorded at a rate of 10 FPS.

Method of operation

The operation of the apparatus 100 according to the invention ? described below.

Conveniently, by reference system is meant a system of coordinates which allow the position of an object in space to be described, preferably unequivocally.

Preferably, the coordinate system comprises three coordinates x, y and z, which are orthogonal to each other and such that the third coordinate is the resultant of the cross product of the other two.

It should be noted that, hereinafter, the triad (x, y, z) mean respectively the values of the three coordinates that define the position of a point in space in a three-dimensional reference system, preferably Cartesian, in which the three axes of this system are orthogonal to each other.

The imaging device 14 ? configured to acquire one or more? images suitable for representing/describing/modeling a three-dimensional body 16, for example a stack of substantially two-dimensional images suitable for representing/describing/modeling (and therefore modeling) a three-dimensional body 16.

Conveniently, the image acquisition device 14 can be connected to the input of the apparatus 100. Conveniently, the image acquisition device 14 ? configured to obtain the volumetric data which describe/model the three-dimensional body 16, and to then make such data available? preferably in the form of at least one computer file - to the apparatus 100, and in particular to the unit? control and processing 6.

The imaging device 14 ? configured to acquire suitable images, preferably two-dimensional, suitable for representing a three-dimensional body 16.

In particular, a three-dimensional body 16 can? be described / modeled by the collection of a plurality? of two-dimensional images 18 in which a plurality? of points in space, marked by a triad of coordinates (x,y,z) a value is assigned, for example a color, thus generating a function C(x,y,z). Conveniently, in the case of a stack of images aligned/stacked along the same axis and spaced apart along said axis, which can? for example be defined as the z axis, we have the function C<z>(x,y), where that is, for each value of ?z?, we have a corresponding digital image C(x,y) where each pixel identified by the coordinates ?x? and ?y? contains a corresponding information that ? defined as the value of function C.

Conveniently, the function C pu? represent a? information of color that, preferably, can? be encoded using a gray scale (and therefore substantially defined by a number), or using the RGB or CYMK model (and therefore be defined by several values, for example by a triad of values in the case of the RGB or CYMK model and therefore be identifiable with a vector). Substantially, therefore, each point (x, y, z) contains information C (x, y, z) which can? be defined by a single number, in the case of a grayscale image, or by a vector, in the case of a color image.

Advantageously, the modeling C(x,y,z) of the three-dimensional body 16, for example by means of a stack of images 18 described with the function C<z>(x,y), can? be loaded in? unit? storage of this unit? control and processing 6, and/or sent to the latter, to carry out cos? a plurality? processing of these images.

Conveniently, said processing pu? consist in the reconstruction of the three-dimensional dataset starting from a plurality? ? preferably from a stack - of two-dimensional images 18 acquired by the image acquisition device 14.

As mentioned, said plurality? of images can? be represented by a stack of images acquired at different depth values? z, and essentially describable with the function C<z>(x,y). Conveniently, therefore, each image Vz can? be described with a corresponding function C(x,y) and the three-dimensional model V (cfr. fig. 4) pu? be reconstructed by means of a summation of the individual Vz images over all z values, as represented in equation (1):

Advantageously, moreover, the unit? control and processing 6 ? configured to interpolate the starting data and/or the data cos? obtained, through known techniques and image processing algorithms, in order to improve the resolution in one or more? of the three spatial coordinates. Conveniently, the? interpolation can? be made on each image Vz, or pu? be made on the three-dimensional model V. Preferably the interpolation on the x and y coordinates (which identify the pixels of each image) pu? be made on the images 18, while the? interpolation on the z coordinate can? be made on the three-dimensional model V.

Conveniently, in this way, ? It is possible to obtain a three-dimensional model V that has a high resolution. Preferably, the three-dimensional model V obtained, before or after the interpolation process, has a higher resolution than that of the display surface 20, so as ? been detected by the distance detector 2. Advantageously, there? allows to have a three-dimensional model V which, when displayed on the display surface 20, can appear substantially continuous, i.e. not grainy or fuzzy.

Conveniently, if the three-dimensional model V contains information relating to the position of the image acquisition device 14 ? in particular relating to the position of the three-dimensional body 16 with respect to the image acquisition device 14, for example the scanner with which it is used; been acquired the CT scan, or the camera with which the photographs were acquired - the unit? control and processing 6 pu? be configured to process said three-dimensional model V in order to refer it to an absolute reference system W through the formula indicated in equation (2) where V<W > indicates the three-dimensional model V in the absolute reference system W, V<S > indicates the image V in the reference system S of the image acquisition device 14, and M<S,W >? a space transformation matrix which contains information on the position of the image acquisition device 14 relative to the three-dimensional body 16 which it is intended to represent, and which allows the following transformation to be carried out:

(2) Advantageously the matrix M<S,W >pu? be calculated so that the volume of data V<W > is substantially on a 1:1 scale with respect to the three-dimensional model V.

Advantageously, moreover, to represent the temporal evolution of the three-dimensional body 16, the unit? control and processing 6 ? configured to perform the following steps. In particular, if the time evolution of the three-dimensional body 16 is defined by a sequence of three-dimensional models V, each of which ? associated with subsequent time instants, each three-dimensional model V pu? be treated separately. Conveniently, if the temporal evolution of the three-dimensional body 16 is represented by a set of voxels, it can? Equation (2) can be applied in which M<S,W >has the function, for example, of a rotation matrix. In the case in which instead the temporal evolution of the three-dimensional body 16 is realized through an animation of a polygonal model, this can? preferably be processed, for example by the unit? of control and processing 6, in order to be transformed into a sequence of three-dimensional objects, to then perform one of the steps described above.

Furthermore, as mentioned, the distance detector 2 ? able to detect the position of the display surface 20. Preferably, the distance detector 2 can? be able to detect the position of the display surface 20 with respect to the reference system defined by/inside the distance detector itself, and in particular for example with respect to the pinhole of the distance detector itself. Pi? in detail, for ?pinhole? means the? intersection between the? optical axis of the lens of the optical system which, preferably ? provided in detector 2, and the plane of the lens itself.

Conveniently, the unit? of control and processing 6, on the basis of the detected data (preferably pre-processed) and coming from the distance detector 2, ? configured to calculate a depth map? S that, in particular, pu? be defined as:

(3) More in detail, the map of depth? Yes a two-dimensional scalar field, which for example pu? be described by a two-dimensional matrix, in which at each point of the field of view (or acquisition) framed (also or only containing the display surface 20), a point which ? distinguished by the coordinates (x,y) ? preferably defined with respect to the reference system of and/or associated with the distance detector 2 - ? associated with a value Fp corresponding to the detected distance of said point with respect to the reference system.

Conveniently, therefore, the depth map? S pu? be considered as an? image in which, each pixel of the image? identified by the coordinates ?x? and ?y?, contains information relating to the distance of the point (which is associated with that pixel) of the visual (or acquisition) field, containing the display surface 20, with respect to a reference system, preferably with respect to the reference system reference of the detector of distance 2. In substance, advantageously, the map of depth? Yes represented as an image (two-dimensional array of points) containing distance information of each point of the acquisition field used (preferably of the field of view framed) with respect to a reference system.

Conveniently, as mentioned, the reference system in which this depth map is described? S pu? be defined by a reference system D defined within the and/or relative to the same distance detector 2, and therefore the corresponding depth map? can? be identified as S<D>.

Advantageously, the data of the distance detector 2 can be sent to the unit? of control and elaboration 6 in order to allow the elaboration of the data relating to the distance of the display surface 20 measured by the distance detector 2, and in particular the data of the depth map? SD containing the position of the display surface 20 from said distance detector 2 (and in particular for example from its pinhole) in the reference system D of the distance detector 2.

Conveniently, the unit? control and processing 6 ? configured to process the depth map? S<D >described and acquired in the D reference system of the distance finder 2 in order to obtain a depth map? S<W >described in an absolute reference system W, as described in the following equation:

(4?) where the transformation matrix M<D,W >includes the information on the position of the reference system D of the distance detector 2 with respect to the absolute reference system W. Advantageously, the matrix M<D,W >pu? be calculated so that the surface S<W >is substantially on a 1:1 scale with respect to the surface S<D>.

Advantageously, the unit? control and processing 6 pu? be configured to process the depth map? S<D> (containing the position of the display surface 20) described and acquired in the reference system D of the distance detector 2, so as to obtain a depth map? S<P >described in the reference system P of (and/or associated with) display 4, as described in the following equation:

(4?) where the transformation matrix M<D,P >includes the information on the position of the reference system D of the distance detector 2 with respect to the reference system P of the viewer 4. Advantageously, the matrix M<D,P >pu ? be calculated so that the surface S<P >is substantially on a 1:1 scale with respect to the surface S<D>.

In this way, advantageously, It is possible to describe/model the display surface 20 independently of the position of the distance detector 2, thus allowing to project images 12 by means of projectors 22 also arranged in positions different from each other, without this altering the projected image, or making it less accurate.

Conveniently, if the apparatus 100 includes a plurality? of (at least two) position detectors 2, 2?, are these preferably configured ? i.e. positioned and directed ? in order to detect the same display surface 20 from a plurality? of different positions and/or angles, to obtain cos? essentially a plurality? partial projection surfaces corresponding to the same display surface 20; conveniently, there? allows you to obtain a detection pi? of the display surface 20, in particular also detecting any undercut portions or in general portions which would not be detectable by a single distance detector 2. Conveniently, the depth maps? S<D1 >and S<D2 >detected and coming respectively from position detectors 2, 2? are sent to? unit? control and processing 6, which ? suitably configured to combine the data of these maps of depth? before or after having changed the reference system D1 and D2 in which the maps of depth? S<D1 >and S<D2 >have been described, i.e. before or after the change of the reference system by using the matrices M<D1,P >/ M<D2,P >or M<D1,W >/ M<D2,W>,

Advantageously, moreover, the unit? control and processing 6 ? configured to process the depth map? S in order to identify and/or extract from said map the portion relating to the display surface 20. Conveniently, the unit? control and processing 6 ? configured to process the depth map? Yes, and preferably the depth map? S<W> described in the absolute reference system W or the depth map? S<P>described in the reference system P of the viewer 4. Advantageously, said depth map? S pu? be processed in order to improve its resolution, preferably at least in the area relating to the display surface 20. Advantageously, this? it is carried out in order to obtain a substantially continuous profile of the display surface 20, and in particular sufficiently dense and/or precise to allow an adequate reproduction of the image to be displayed. Preferably, the unit? control and processing 6 ? configured to process depth map data? S so as to create a three-dimensional model, which substantially reproduces the three-dimensional shape of the surface 20 detected by the distance detector 2.

Advantageously, moreover, the unit? control and processing 6 pu? be configured to process the depth map? S in order to identify and/or extract the portion relating to the display surface 20 and in order to model it by means of a point cloud or a polygonal mesh.

Preferably, the display surface 20 can be represented/described by a plurality? of points, each described by its own spatial coordinates. Advantageously, from the points of said cloud of points pu? be then generated a polygonal mesh (for example using the points of the cloud as vertices of the polygons of said mesh), to model cos? the display surface 20 by means of a three-dimensional model.

Advantageously, in the case in which the display surface 20 is described/represented by means of a mesh of polygons, each polygon of the mesh can preferably be applied a texture (i.e. a color content), preferably of high resolution.

Data visualization

The unit control and processing 6 ? configured to process - on the basis of the data detected by the distance detector 2 relative to the display surface 20 - the C(x,y,z) modeling of the three-dimensional body 16 so as to create at least one image 12, relating to said three-dimensional body 16, to be displayed on said display surface 20.

Conveniently, said at least one image 12 is created in real-time. Preferably, said at least one image 12 to be displayed is created at a frequency for example comprised between 25 and 30 FPS, and is displayed with a substantially corresponding frequency.

Preferably, said at least one image 12 to be displayed is created in real time each time said distance detector 2 detects a change in the position in space or in the distance of said display surface 20 with respect to a reference system.

Conveniently, said data detected by the distance detector 2 relative to the display surface 20 include the depth map? S which describes/represents the distance of the display surface 20 with respect to a reference system, which advantageously can? be the reference system D of the distance finder 2 and/or the reference system P of the viewer 4 and/or an absolute reference system W.

Conveniently, said C(x,y,z) modeling of the three-dimensional body 16 comprises a volumetric dataset of said body 16 which can be represented/described in the form of an image stack and/or point cloud and/or polygonal mesh and/or voxel dataset.

Conveniently, the unit? control and processing 6 ? configured so that, starting from the volumetric dataset V that ? preferably - ? defined by a stack of images aligned along the Z axis

(1)

and on the basis of the depth map? S - created by/by the distance detector 2 - describing/representing the distance of the display surface 20 from a reference system:

(3) carries out the following operations in order to create the image 12, to be projected and/or implemented by the viewer 4 on the display surface 20.

In particular, for each pixel xi, yi of image 12 to be created, carry out the following operations:

- extracts from the depth map? Yes, the value Fi associated with the pixel xi, yi, - selects within the volumetric dataset V, the image Vz having z=Fi, - in the image Vz cos? selected, identifies the C value associated with the pixel xi, yi,

- in the image 12 being created, to the pixel xi, yi, associate the content C cos? identified.

Conveniently, the aforesaid sequence of operations is carried out for all the pixels xi, yi necessary to form the image 12 to be displayed, by means of the viewer 4, on the display surface 20.

Conveniently, therefore, in order to create the image 12 to be displayed on the display surface 20, the unit? of control and processing 6 extracts ? on the basis of the data/values of the depth map? S - the corresponding data/values from the volumetric dataset V (containing the volumetric data of the three-dimensional body 16 to be displayed).

Advantageously, in order to form the image 12 to be displayed on the display surface 20, the volumetric dataset V can? be intersected with the depth map? S relative to the display surface 20. In particular, for this purpose, we use the volumetric dataset V<W > described in the absolute reference system W, and the depth map? S<W >of the display surface 20 described in the absolute reference system W. Conveniently, in this case, the two data records V<W >and S<W >are already? described in the same reference system W, and therefore substantially in the same space, and therefore the superimposition takes place by means of a simple comparison of the coordinates. Advantageously, therefore, the unit? control and processing 6 pu? do the following

(6) Substantially, therefore, as represented in figure 11, the image to be displayed 12 on the display surface 20 is defined by ??<?>, cio? from the values of the three-dimensional dataset V<W > which are obtained by intersecting/cutting the dataset itself with the depth map? S<W>. In other words, each pixel of the image to be displayed 12 contains the value (for example in terms of colour) of the corresponding pixel of the image which is obtained by intersecting/cutting the three-dimensional dataset V<W > with a cut section defined by the values of the depth map? S<W>.

Image display

Conveniently, once the image 12 has been created/defined on the W reference system, the unit? control and processing 6 ? configured to process the image itself and the depth map? S<W >relative to the position of the display surface 20 in the reference system W so that said image can be correctly displayed by the viewer 4 on the display surface 20.

In particular, the unit? control and processing system 6 processes the image 12 and the position of the display surface 20, both described in the reference system W, so as to describe them as a function of the space seen by the display 4 itself, and in particular for example of the truncated cone , or spherical sector, which is projected by the projector 22 defining said image viewer 4. Pi? in detail, this processing? carried out through the use of appropriate projective transformation matrices F defined on the basis of the characteristics (for example on the position, orientation and optics) of the viewer 4. Conveniently, the matrices F may not be invertible, as they are used to project a substantially three-dimensional image on a two-dimensional space. In particular, can be expected:

- a matrix F<I,W,P > for the projective transformation (in particular by means of a projection truncated pyramid) of the coordinates expressed in the absolute reference system W to the reference system I of the image 12 to be displayed, and

- a matrix F<I,T,P> for the projective transformation from the reference system T of the display surface 20 to the reference system I of the image 12 to be displayed.

Advantageously, the matrix F<I,W,P >can? be defined so that the transformation takes place substantially on a 1:1 scale.

Advantageously the matrix F<I,T,P >pu? be defined so that the transformation takes place substantially on a 1:1 scale.

Conveniently, in this way, the display 4 correctly displays the image 12 on the display surface 20.

Conveniently, in the event that the apparatus 100 comprises a plurality? of (at least two) projectors 22 of images the? operation can? be performed separately for each of these.

Advantageously, all the previous operations are carried out substantially in real time, and what? allows prompt adaptation to any changes in position of the display surface 20. Basically, in this way ? is it possible for the user to essentially ?navigate? within the volumetric dataset V through a displacement and/or deformation of the display surface 20. Preferably, therefore, by modifying the position, orientation and conformation of the display surface 20 in space, the operator can? change the image 12 created and displayed/implemented on said surface, thus managing? to navigate within the volumetric data that describe/model a certain three-dimensional body 16.

Conveniently, moreover, there? also allows? to display on the display surface 20 videos (that is, a succession of images over time).

Advantageously, moreover, since? all the transformations performed are implemented so that the image 12 displayed on the display surface 20 is on a 1:1 scale with respect to the volumetric dataset V relating to the three-dimensional body 16, the user or the person viewing said image can? get a particularly reliable idea of the real dimensions of the three-dimensional body 16.

From what has been described it is clear that the apparatus according to the invention is particularly advantageous because:

- allows you to view volumetric data on surfaces of different shapes, which can be moved in space and/or be modified in time and space to navigate so through said volumetric data,

- allows you to view volumetric data on any surface with a defined scale,

- it allows you to modify the display surface during the display itself, in order to allow a correct perception of the data volume by the user.

The present invention ? been illustrated and described in some of its preferred embodiments, but it is understood that executive variants can be applied to them in practice, without however departing from the scope of protection of the present patent for industrial invention.

Claims (10)

1. Apparatus (100) for browsing at least one volumetric dataset (V), preferably of a three-dimensional body (16), characterized in that it comprises: - at least one detector of distance (2) that ? configured to detect the position of a display surface (20) on which ? intended to display at least one image (12) relating to the content of said volumetric dataset (V), - at least one viewer (4) that ? configured to implement display of said at least one image (12) on said display surface (20), - a?unit? of control and elaboration (6), that ? electronically connected with said distance detector (2) and with said display (4), and which, starting from said volumetric dataset (V) and on the basis of the data detected by the distance detector (2) relative to the position of the display surface (20), selects and/or processes the data of said volumetric dataset (V) to define said at least one image (12) relating to the content of said volumetric dataset (V) and of which to implement the display on said display surface ( 20) by means of said display (4). 2. Apparatus according to claim 1, characterized in that it also comprises a display surface (20) that ? mobile in space, thus changing its position and/or orientation and/or conformation in space. 3. Apparatus according to one or more of the preceding claims, characterized in that said viewer (4) comprises a visualization display (21) which defines as follows? said display surface (20). 4. Apparatus according to one or more? of the preceding claims, characterized in that it comprises a device (1?) comprising said at least one viewer (4) and said unit? control and processing (6), and by the fact that said display surface (20) ? defined by the visualization display (21) of said viewer (4), said at least one distance detector (2) being external with respect to said device (1?). 5. Apparatus according to one or more of the preceding claims, characterized in that said viewer (4) comprises a projector (22) to thus project the said image (12) to be displayed on said display surface (20) which ? what? external to said viewer (4). 6. Apparatus according to one or more of the preceding claims, characterized in that it comprises a single device (1) comprising said at least distance detector (2), said at least one display (4) and said unit? control and processing (6), and also characterized? by the fact that said display surface (20) ? external to said device (1). 7. Apparatus according to one or more? of the preceding claims, characterized by the fact that the unit? control and processing (6) ? configured so that, starting from said volumetric dataset V that ? defined by a stack of VZ images aligned Mon go the Z axis: and on the basis of a depth map? That ? created by/by the distance detector (2) and which describes/represents the distance of the display surface (20) from a reference system, performs the following operations in order to define the image (12), to be projected and/ or implement via the viewer (4) on the display surface (20): - extracts from that map of depth? S, the Fi value associated with each pixel xi, yi, - select within the volumetric dataset V, the image Vz having z=Fi, - in the image Vz cos? selected, identifies the C value associated with the pixel xi, yi, - use C content cos? identified to define said image (12), preferably by associating the content C so? identified to at least one pixel of the image (12) being defined and/or preferably by associating a pixel of the image (12) being defined with a value calculated from at least two contents C so? identified. 8. Apparatus according to one or more of the preceding claims, characterized by the fact that the unit? control and processing (6) ? configured so that, in order to define the image (12) to be displayed on the display surface (20), it intersects said volumetric dataset (V), once it is? been brought and described in an absolute reference system (W), with a depth map? Yes what? created by the distance detector (2) and which describes/represents the distance of the display surface (20) in said same absolute reference system (W). 9. Apparatus according to one or more of the preceding claims, characterized by the fact that, once said image (12) has been defined, the unit? control and processing (6) ? configured to process the? image (12) cos? defined and the position of the display surface (20), both described in the same reference system (W), so as to describe them according to a further reference system (I), preferably associated with said display (4). 10. Apparatus according to one or more? of the preceding claims, characterized in that, starting from the data of said display surface (20) detected by/by means of said distance detector (2), the unit? control and processing (6) ? configured to model said display surface (20) by means of a point cloud and/or by means of a polygonal mesh and/or a voxel dataset.