FR3077662A1 - METHOD OF PROCESSING A VIEW OF A DIGITAL PLAN - Google Patents

Abstract

According to a method of processing a view of a digital plane by at least one computing display device, connected through a computer network to a server (MO): • we receive on the server (MO) a source file (DOC_PDF) coding the digital plane, • is produced from the source file (DOC_PDF) at least one master file comprising a matrix image of at least a part of the digital plane and resolution information (RES) indicating the resolution of the 'picture ; • for each master file, we build a visualization file (DOC_HTML) from the master file; • we memorize the visualization file (DOC_HTML) and display it on a screen; characterized in that, for the production of a first of the master files, the resolution is determined according to a decreasing resolution law according to a dimension of the master file and the image of the master file is generated with said resolution.

Description

TECHNICAL AREA

The invention relates to a method of processing a view of a digital plan by at least one computer display device, connected through a computer network to a computer device forming a server. It also relates to a system implementing said method.

PRIOR ART

A plan, or more generally a technical drawing, is by nature a particular document: it is a graphical or schematic modeling of an object or a system (example: building, cities, machines, etc.), existing or to create, which is supplemented by a certain amount of information such as, for example, its update number (usually called "version"), its name, its scale, its ratings and its orientation. All of this information and a digital image of the plan representation can take several formats by computer (example: pdf "portable document format", DWG associated with autoCAD © software, etc.) depending on the user's wishes and / or software at its disposal to produce a computer file encoding the plan and its associated information. The plane can also be a two-dimensional representation of an object modeled in three dimensions for which we have defined an axis of view and a projection method.

It is very common that plans are in two dimensions, and intended for rectangular display or reading supports: telephone, computer, television, monitor screens, standard paper prints, etc.

It is known to use plans or technical drawings within collaborative mobile computing devices made available to employees of a company. One of the implementations of this technique relates, for example, to computerized display devices for "lifting reservations" used in the construction industry to generate task lists and facilitate activity monitoring. These devices are such as touch pads, laptops, smartphones, communicating with one or more servers by means of any telecommunications network, which can be of the EDGE, 3G, 4G or Wifi type, and each hosting software allowing the users generate information interacting with the most up-to-date plan pages the system knows. The plans constitute, for these devices, input data essential for their proper functioning. They are project documents liable to be modified or updated regularly. We then speak of version upgrade. In cases where the plans are very complex, by their size or by the density of information they contain, the processing of such a plan by mobile devices of limited capacity may prove to be uncomfortable, if not impossible.

Document FR 3 043 806 A1 has proposed a digital plan visualization method according to which a source file encoding the digital plan is received on the server, a master file comprising a raster image of the plan is produced from the source file digital with a predetermined image resolution, a visualization file is constructed from said master file in the form of an HTML document including a mosaic of images obtained by cutting the image from the master file. This document can then be easily viewed with an application such as an Internet browser on viewing devices. In fact, the source file is generally a vector representation of the plan, for example in the form of a PDF document (acronym for "portable document format"), or DWG provided by computer-aided design software such as Autocad. ®. The display of such documents requires strong processing capacities of the display device. By generating an image on a server having these capabilities, it is easy to view the image generated on a screen of the viewing device. Thus, even complex plans can be viewed on devices of limited capacity.

The document FR 3 048 095 A1 shows an additional functionality, making it possible to predefine a particularly interesting area of the plan, then to display it directly on the display device.

However, it has been found that in certain circumstances, in particular for large plans, the display of the display file by the display device exceeds the limits of processing capacity of said device. It has also been found that, because of having a fixed resolution for the generation of the image of the master file, certain details could disappear, in particular for the small plans.

It is therefore an objective of the invention to provide a method for processing a digital plan in order to allow viewing of a digital plan, even a large one, on devices of limited capacity so as to exceed the limits of the prior art.

STATEMENT OF THE INVENTION

With these objectives in view, the invention relates to a method of processing a view of a digital plane by at least one computer display device, connected through a computer network to a computer device forming a server, method according to which a source file encoding the digital plane is received on the server, at least one master file is produced from the source file comprising a matrix image of at least part of the digital plane and resolution information indicating the resolution of the 'picture ;

• for each master file, a visualization file is constructed from said master file;

• the viewing file is stored in a memory of the viewing device and displayed on a screen of said device;

characterized in that, for the production of a first of the master files covering a first height and a first width, the resolution is determined according to a law of decreasing resolution as a function of a dimension of the master file and the image of the master file with said resolution, the dimension being chosen from a group comprising the first width, the first height and the product area of the first width and the first height.

As is known, a computer file is a collection of digital information gathered under the same name, recorded on a computer storage medium and handled as a unit. Finally, a matrix image, or "point map" (bitmap, in English), is an image consisting of a matrix of points, usually colored or in gray level, that is to say, consisting of a table, a grid, etc., where each box has its own color or gray level value and is considered as a point in the image. It is therefore a juxtaposition of color or grayscale points forming, as a whole, an image. The digital plan is a representation in digital format which can be in two dimensions or in three dimensions. It can be a vector representation of the plan, for example in the form of a PDF or DWG document. The master file is obtained from the source file by an automatic transformation or in a step in which a user is involved to define for example a viewing angle, an optional cutting plane and a projection method for a three-dimensional model, a framing on a two-dimensional model or the choice of pages. The master file comprises a first height and a first width corresponding to the format in which it is intended to be printed. According to the invention, according to one of these dimensions, for example, the largest of these, or according to the product of these two dimensions, and therefore of the surface covered by the master file, it is determined to what resolution the master file should be generated. The resolution is expressed in number of points, or pixels, per unit of length, and therefore makes it possible to determine the number of points on the width and on the height which will be conferred on the master file. The law of resolution can be continuous, like a straight line with negative directing coefficient or a decreasing exponential, or be constant by stage, the stages being decreasing. In this way, the visualization file is optimized so that it contains sufficient detail when the plan is small, A3 or A4, or remains visible when it is large, for example when it is planned for A1 or AO format.

According to a first embodiment, after reception of the source file, at least one zoning part included inside the first master file is defined and a second of the master files corresponding to this zoning part is constructed, the image of the second master file with a resolution determined according to the law of resolution applied to the zoning portion, and a second display file is generated corresponding to the second master file, the display device making it possible to choose which of the display files is displayed. The definition of a zoning part is intended to prepare the display of an area of the plan that is of particular interest, for example because it corresponds to an area dense in detail or to a subject on which the work is focused. at a particular time. This definition then makes it possible to generate a second master file for viewing this zoning portion, which will have, due to the law of resolution, a resolution greater than or equal to that of the first master file. We will be able to obtain more details in the display of this zoning section. The choice of display file is made at the display device, possibly directly by the user.

According to an improvement, the display on the display device is chosen to display the second display file if the displayed area is contained in the second display file, and the first display file if the displayed area is outside the area covered by the second visualization file. The user does not have to worry about the selection of the visualization file. The user can choose the area he wants to display, for example by zooming in and out. Depending on its choice, the visualization file to be visualized will be selected. We can consider that the area to be displayed is outside the area covered by the second viewing file as soon as a portion to be displayed is not covered by the second viewing file, or as soon as no part of the second viewing file visualization is no longer included in the area to be displayed. We can also apply a rule between these two extremes by considering that the area to be displayed is outside the area covered by the second visualization file if for at least one of the dimensions of the area to be displayed, the proportion covering the area of the second viewing file is less than a predetermined threshold. The dimension is for example the height, the width or the surface. Other rules may apply.

According to a second embodiment, at least a third master file is produced covering the same area as the first master file and with a third resolution greater than the first resolution, the third display file associated with the third master file is generated, we define a sub-part of the plan as work area, we determine a target resolution according to the law of resolution applied to the work area and we display at least part of the work area with the visualization file whose resolution is just lower or equal to the target resolution. Several visualization files are thus prepared at different levels of resolution, but covering the entire surface of the plan. The selection of the display file at the display device is made according to the work area. Depending on the dimensions of this work area, the target resolution is determined. Then, among all the display files available on the display device, the one that has the best resolution is chosen, without exceeding the target resolution. This allows you to view the best resolution available for the work area without exceeding the processing capabilities of the display device.

According to an improvement, when the display device is intended to zoom in on an area of the map, the zoom out is limited so as to display at most only a partial area of the map. Thus, the display device does not make it possible to display the entire surface of the plane. It has been found that this limitation also makes it possible to limit the use made of the capacities of the display device, in particular the use of the random access memory. This limitation preserves the ability to display the plan, even of large dimensions, on the display device.

According to an advantageous arrangement, at least two intermediate files are produced from the master file, each intermediate file comprising a matrix image obtained from a series of matrix images obtained by cutting out the matrix image from the master file and at least resolution information corresponding to the resolution of the master file, the intermediate files used to construct the display file associated with said master file. This subdivision of the image of the master file allows easier manipulation of the visualization file, in particular during the transfer of the visualization file from the server to the visualization device. It also allows updating of only one area of the plan without the need to transfer the entire plan, but only the images of the modified intermediate files. The processing by the display device is also improved because this makes it possible to use an application which loads into memory only the part of the display file which must be displayed, thereby limiting the use of the RAM. The invention also relates to a system for processing a view of a digital plan comprising a computer device forming a server, at least one computer display device connected to the server through a computer network, the server being configured to receive a source file encoding the digital plane, produce from the source file at least one master file comprising a matrix image of at least part of the digital plane and resolution information indicating the resolution of the image, and for each file master, construct a visualization file from said master file, the visualization device being configured to receive the visualization file through the communication network and comprising a memory for storing the visualization file and a screen for displaying the visualization file ;

characterized in that, for the production of a first of the master files covering a first height and a first width, the server is configured to determine the resolution according to a law of decreasing resolution as a function of a dimension of the master file and generate l image of the master file with said resolution, the dimension being chosen from a group comprising the first width, the first height and the product area of the first width and the first height.

DESCRIPTION OF THE FIGURES

The advantages and the invention and other objects of the invention will appear in the detailed description which follows, in connection with the accompanying drawings and among which:

• Figure 1 is a schematic view of a computer system according to the invention for processing and viewing a digital plan;

• Figure 2 is a schematic view of the data constituting a display file according to the invention;

• Figure 3, subdivided into two parts 3A and 3B, is a flowchart of a process for processing and viewing a plan according to the invention; and • Figure 4 is a graphical representation of a resolution law expressing a resolution as a function of a dimension of the plane.

DETAILED DESCRIPTION

Referring to FIG. 1, a system 10 according to the invention comprises a plurality of display devices M1, M2, Mn each equipped with a processor, a random access memory, a mass storage memory, d '' a display screen and a communication module with at least one computer communication network RI, for example a wireless communication network of WIFI, EDGE, 3G, 4G, etc. type, and each embeds a system of for the management of the various on-board hardware and software elements. Each display device also has software capable of handling files or objects called "display", as described below. For example, the display devices M1, M2, ..., Mn are touch tablets, portable computers and / or smartphones, constituting a fleet of portable devices for the use of employees in the field of construction, maintenance. , works, property management, maintenance of roads or networks, or more generally of any profession requiring the intervention on site of mobile technical teams possibly belonging to different structures or companies. The display devices M1, M2, ..., Mn can all be identical, or be of different models as is usually the case. The display devices are notably different in the case where different companies have to work together and exchange information on the same project. These companies do not necessarily have the same IT equipment available.

The system 10 also includes a central device MO forming a server, for example a UNIX server, capable of communicating with each display device M1, M2, ..., Mn through an RI network, via for example an application of the type WEB developed in JAVA. The MO server has appropriate hardware and software resources to process different types of computer formats in which a plan can be stored, such as vectorized files of the PDF (for “portable document format”) or DWG (computer format of autoCAD software) type. ©). MO has a clock capable of distributing times.

The method according to the invention comprises two main sets of computer processing, a first set of processing being implemented by the MO server, capable of interpreting PDF files, for example using a toolbox such as PDF BOX available at the address https://pdfbox.apache.org/, and a second set of treatments being implemented by each display device M1, M2, ..., Mn. The first set of treatments is advantageously optimized as a function of the display capacities of the display devices M1, M2, ..., Mn. More particularly, a digital plane of large dimensions in pixels is cut into raster images of the same dimensions, or smaller, than the dimensions Ld (width) and Hd (height) in pixels of the smallest screen among the screens of the display devices M1 , M2, ..., Mn. Thus, each device is capable of displaying in full format each matrix image produced by the MO server. The second set of processing operations consists in recombining the matrix images in a display file so as to display the digital plane on the screens of the display devices M1, M2, ..., Mn.

FIG. 2 illustrates an example of a computerized plan display file recorded in the memory of each display device M1, M2, ..., Mn. The visualization file consists of:

• a first DOC_HTML file having META metadata, comprising identification data ID uniquely identifying the plan and DATE version data uniquely identifying the version of the plan, as well as an HTML portion comprising a set of containers, for example defined by DIV tags, linked to images, for example by means of IMG tags;

• intermediate computer files of image type DOC_PNG1, ... DOC_PNGP, for example in PNG format, for "portable network graphie", constituting a breakdown of the digital plane. Each intermediate file comprises conventional META1 metadata (eg the IHDR header of a PNG format comprising the height and width of the image), a block of pixel data constituting an image, as well as META2 metadata specific to the invention. , comprising in particular image resolution data (RES) and image position data (POS) in the plane, as well as the identification data (ID) and version (DATE) of the plane;

• a third DOC_TXT file comprising a set of measurements and annotations carried out on the plan by means of the device, and recorded for example in a text format.

As will be described below, reading the DOC_HTML file in an internet browser allows you to recompose the digital plan by displaying the raster images stored in the DOC_PNG1, ... DOC_PNGQ files, as well as the measurements and annotations contained in the DOC_TXT file . There will now be described an embodiment of a digital plan processing and display method according to the invention, illustrated by way of example in relation to a source file of PDF type comprising P pages, P being an integer greater than or equal to 1. The PDF format is usually used for the communication of plans between computer devices. However, due to its vector nature, the display of a PDF file requires significant material resources, the operations of enlarging and reducing a vector image being, for example, very long on devices of the tactile tablet type not having not a powerful processor and a consequent RAM memory. Reading a large PDF plan, such as AO, is even impossible on the least efficient mobile devices such as tablets or smartphones.

Referring to the flow diagram of FIG. 3, the method begins, at 20, by the reception by the system 10 of a DOC_PDF file in PDF format coding a digital plan, this file being able to be received by one of the devices M1, M2, ..., Mn or by the MO server. At 22, the receiving device determines if the plan submitted is a new plan or if it is a new version of a plan already known to the system, the receiving device storing for example in memory a list of the set known plans and their different versions, or else interrogates one of the devices, for example the MO server, having the function of keeping such a list up to date. Hereinafter, a "series of plans" corresponds to the set of files consisting of a new plan and its successive updates (or versions).

According to a first semi-automatic variant, it is left to a user to control the recording of the plan received by the system. In particular, the receiving device has a graphical interface offering the user, at 24, a different recording button for each of the known series of the system, and an additional recording button allowing the recording of a new plan. unknown to the system 10. The buttons bearing the name of a series allow you to register an additional version, which in turn will become the version considered to be the most up-to-date of this series. The button allowing the registration of a new plan is conventionally called "new plan". This button is visually different from the buttons for saving a new version. Within the framework of this preferred variant of embodiment, it is therefore its graphic charter which differentiates it. By selecting either of the registration buttons, the user identifies the plan submitted to the system as either a completely new plan or the most up-to-date new version in a series of plans. In the case of a new plan, the receiving device asks the user to name this plan, prohibiting, to avoid conflicts, the use of the name of a series already known. The user then freely fills in an alphanumeric input field provided for this purpose. In the case of the new version of a known plan, the name automatically given to this plan is the name of the series. Each plan is thus uniquely named, its name constituting the identification data of this plan. In both cases, this alphanumeric value is named "NOMPLAN". In the context of this preferred embodiment, the user then loads, at 26, the plan received in PDF format on the MO server.

According to a second fully automated variant, the receiving device implements the recording function automatically, by itself assigning a name to a new plan, then transmits the source PDF file to the MO server.

Once this source file, named “DOC_PDF”, received by the MO server, software hosted on the latter begins, in 28, by automatically time stamping the loading of this source file, by comparison with the internal clock of the MO server, then the software associates with this file the value "NOM_PLAN" as identification data. Each source file is then identified by a unique data pair (DATE, PLAN NAME).

This being done, the MO server automatically converts to 30, the P pages of the PDF source file respectively into P distinct two-dimensional raster images, in image format.

PNG, each of the P images therefore corresponding to one of the pages of the DOC_PDF file, each page having a width and a height expressed in dimensional units of measurement, for example in centimeters. The conversion of each of the P pages is carried out with a resolution per page, possibly different from one page to another, and determined according to a law of resolution. The resolution is a data stored in each image as RES metadata. This matrix image incorporating the resolution information of said image will subsequently be called a MAST master file. According to the invention, each of the resolution laws used is decreasing as a function of a characteristic dimension of the MAST master file, the characteristic dimension being chosen from the width, the height or the surface produced by the width and the height. Preferably, the characteristic dimension is the surface. FIG. 4 shows an example of a law of decreasing resolution by stages. The laws could be refined or be decreasing exponentials. As an example, we could determine a resolution of 300 dpi (dots per inch, point per inch) for an area of 6237 cm ² (A4 format) and 72 dpi for an area of 49896 cm ² (A1 format). In the context of an alternative embodiment, it would have been possible, for example, to use different laws for different series of planes. In another variant, it would have been possible to use different laws for different pages within the same series of plans.

The MAST master file is in particular identified by a single integer value, for example called "PAGE" specific to the position of this page within the DOC_PDF document. For example, it is set PAGE = 1 for the first page of the DOC_PDF file, PAGE = 2 for the second page of the DOC_PDF file, etc. The conversion of the PDF file into PNG images is for example carried out using the "ImagelOUtil.writelmage" function of the "PDF BOX" toolbox installed on the MO server. The scale of the plane is therefore known, so that the scale of the plane is also transmitted through the RES resolution. Thus, the resolution RES makes it possible to approximate physical dimensions of the paper plane, from measurements of distances between pixels made on the display devices M1, ..., Mn.

In a following cutting step 32, the software of the server MO first identifies the dimensions, in pixels, of each of the master files. These dimensions are whole values denoted Lm (Width) and Hm (Height). Then, the master files of which at least one of the dimensions Lm or Hm is greater than the dimensions Ld and Hd, constituting the base of minimum characteristics common to the display devices M1, ..., Mn, and stored in the server MO, are split into a set of intermediate files corresponding to smaller sub-images, of dimensions smaller than the dimensions Ld and Hd. On the other hand, the master files, whose two dimensions Lm and Hm are less than the dimensions Ld and Hd, are not modified.

For this purpose, the server MO performs for example the Euclidean division of the too high dimension of the master file MAST by the corresponding dimension Ld or Hd, according to the following relationships:

• If Lm> Ld, then the parameters p and r such that Lm = Ld.p + r are calculated, where p and r are positive integers and r is strictly less than Ld;

• If Hm> Hd, then the parameters q and s such that Hm = Hd.q + s, are calculated, where q and s are positive integers and s is strictly less than Hd.

The MAST master file is then broken down into (p + 1) times (q + 1) raster sub-images of the same resolution RES as the MAST master file and whose dimensions are less than or equal to the characteristic dimensions Ld and Hd. In particular, in the orthonormal coordinate system, noted R, originating from the lower left corner of the MAST master file and whose standard is equal to 1 pixel, for i integer varying from 0 to p-1 and for j integer varying from 0 to q -1, the sub image Sl (i, j) is composed of all the pixels of the master MAST file with coordinates (x; y) such as:

i. Ld <x <(i + 1) .Ld

j. Hd <y <(j + 1) .Hd

These sub-images Sl (i, j) are of height in pixels equal to Hd and of width in pixels equal to Ld.

Still in this same reference frame R, for i integer varying from 0 to p-1, the subimage Sl (i, q) is composed of all the pixels of the master file MAST with coordinates (x; y) such as:

i. Ld <x <(i + 1) .Ld

q.Hd <y <q.Hd + s

These sub-images S (i, q) are of height in pixels equal to s and of width in pixels equal to Ld. Still in this same frame of reference R, for j integer varying from 0 to q − 1, the sub image Sl (p, j) is composed of all the pixels of the master file MAST of coordinates (x; y) such as:

p.Ld <x <p.Ld + r

j. Hd <y <(j + 1) .Hd

These sub-images S (p, j) are of height in pixels equal to Hd and of width in pixels equal to r. Still in this same reference frame R, the sub image Sl (p, q) is composed of all the pixels of the master file MAST with coordinates (x; y) such as:

p. Ld <x <p.Ld + r

q. Hd <y <q.Hd + s

This subimage S (p, q) is of height in pixels equal to s and of width in pixels equal to r.

The decomposition of the MAST master file into these sub-images is ensured, in the context of this preferred embodiment, by means of the “drawlmage” function of the PDFBOX toolbox. At the end of these steps carried out by the MO server, the plan in PDF format, identified by a pair (DATE, NOMPLAN) unique, is thus broken down into P master files, themselves broken down into (p + 1) times ( q + 1) matrix sub-images having the resolution RES, in PNG format, and the dimensions of which, which are also known, are less than the minimum technical dimensions Ld, Hd, of the screens of the viewing devices M1, ..., Mn . Each MAST master file can have its own RES resolution, and therefore different from that of the others, but this is not compulsory. The resolution value RES of a MAST master file is determined by the law of decreasing resolution. However, each subimage of the same MAST master file has the same RES resolution as this MAST master file. The server MO therefore splits the initial plan in PDF format into Q raster images stored in an image format DOC_PNG1, ..., DOC_PNGQ, for example PNG, each identified uniquely by eight parameters (DATE, PLAN NAME, PAGE, i, j, WIDTH, HEIGHT, RES) stored as metadata of the corresponding PNG file, the WIDTH and HEIGHT parameters being respectively the width and the height in pixels of the image. These eight parameters, and in particular the PAGE parameters, i and j, uniquely code the position of the matrix image in the plane and are used by the display devices M1, ..., Mn for the reconstruction of the plane. The display devices M1, ..., Mn store the dimensions Ld and Hd for this recomposition or, in another variant, these dimensions are also stored as metadata of the sub-images SI and therefore communicated to the display devices M1, ..., Mn.

All the images in PNG format DOC_PNG1, ..., DOC_PNGQ, identified by their parameters, are then communicated, at 34, by the server MO to each of the display devices M1, ..., Mn. By their format, they are already guaranteed to be able to view them, a matrix image being in fact usually readable by any conventional computer device.

Following the reception, in 36, of the series of images DOC_PNG1, ..., DOC_PNGQ by a display device M1, ..., Mn, the latter records the images received in its mass memory and then implements a recomposition of the cut digital plan.

More particularly, each display device M1, ..., Mn embeds software which makes it possible to reconstruct each master file MAST originating from the source file DOC_PDF by juxtaposing the images having the identical triplet (DATE, PLAN NAME, PAGE). It will be noted on this point that the recomposition algorithm described below does not apply any transformation, or image processing, to the images of the series, and only consists of comparisons of integers and the definition of containers. . It can thus be implemented including by display devices with very limited hardware and software resources.

More particularly, in a step 38, the display device M1, ..., Mn automatically generates P interpretable objects, faithful to the P master files of origin, resulting from an intelligent organization of the sub-images from the master file MAST at by means of a visualization file as described in FIG. 2, and more particularly an HTML document which makes it possible to display the images and navigate between them, as well as between the different pages, in order to visualize the plan. The P objects in question are for example HTML containers of an HTML file, each object being composed of 3 stages, namely composed:

• a main container, in which there are line containers;

• said line containers comprising image containers;

• said image containers calling the sub-images in PNG format saved in the memory of the device.

These P objects can be displayed by the display device. As described above, in the particular case of display by means of an internet browser, these containers are for example “div” tags and “img” tags.

In particular, for each set of images received having the same parameter values (DATE, NOMPLAN), but having a different parameter value (PAGE), an interpretable object is created in an HTML document DOC_HTML identified by the parameters (DATE, NAME PLAN, PAGE) and recorded by the display device. To generate the main container for this object, all images with equal parameters (DATE, PLAN NAME, PAGE) are selected. For each parameter value “i” among the selected images, the sum of the parameters “HEIGHT” of the images having this value “i” is produced, this sum being denoted H * and which logically is equal to the height Hm of the file corresponding MAST master. This operation is also carried out to calculate a width L * which logically is equal to the width in pixels Lm of the corresponding master file MAST. Once the height H * and the width L * of the MAST master file have been reconstructed, a rectangular container, whose height, in pixels, is equal to H * and whose width, in pixels, is equal to L * is generated in the HTML document. It is the main container CP of the object. We denote R * the orthonormal coordinate system originating from the lower left corner of this container and whose standard is equal to 1 pixel.

Thus, we have in R * the main container which will contain all the pixels of coordinates (x; y) such as:

<x <L * <y <H *

Inside this main container CP, line containers are then inscribed. For this, and still working from the group of images received having the same values (DATE, PLAN_NAME, PAGE), the display device identifies the value q * which is the highest positive integer among the values "j ". Logically q * = q. We note that the initial cutting was done so that the images having the same values j also have the same value "height". This value is worth h * = Hd for j integer varying from 0 to q * -1 and s * = s for j = q *. For j integer increasing from 0 to q *, the display device generates a container of rectangular lines C (j) whose width in pixels is L * and whose height is equal to the value "height" of the images having the same value of parameter j. This container C (j) is contained in the main container so that its lower left corner coincides with that of the pixel of coordinates (1; j.h * + 1) in R *. Thus, we have in R *:

• For q *> 0, and for j an integer varying from 0 to q * -1, the row container C (j) will contain all the pixels with coordinates (x; y) such as:

<x <L *

j.h * <y <(j + 1) .h * • For j = q *, the row container C (q *) will contain all the pixels with coordinates (x; y) such as:

<x <L * q * .h * <y <q * .h * + s *

Inside each of the line containers C (j), the display device then incorporates image containers, named Cl (i, j). For this, and still working from the group of images received having the same values (DATE, PLAN NAME, PAGE), the display device identifies the value p * which is the highest positive integer among the values " i ". Logically p * = p. It is noted that the initial splitting was done so that the images having the same parameter values "i" also have the same value "WIDTH". This value is worth l * = Ld for i integer varying from 0 to p * -1 and r * = r for i = p *. For i integer increasing from 0 to p *, at j fixed, the device therefore generates the rectangular image container Cl (i, j) whose height in pixels is equal to the height of the line container C (j), c 'is to say either h * or s *, and whose width is equal to the value of the parameter "WIDTH" of images of the same i. This container Cl (i, j) is contained in the container of lines C (j) so that its lower left corner coincides with that of the pixel of coordinates (i.I * + 1; j.h * + 1) in R *.

So we have in R *:

• For q *> 0 and p *> 0, for j integer varying from 0 to q * -1, for i integer varying from 0 to p * -1, the image container Cl (i, j) includes the set of pixels of the initial MAST master file with coordinates (x; y) such as:

i.l * <x <(i + 1) .l *

jh * <y <(j + 1) .h * • For i = p *, the image container Cl (p *, j) includes all the pixels of the initial MAST master file with coordinates (x; y) such as :

p * I * <x <p * .l * + r *

jh * <y <(j + 1) .h * • For j = q *, for i integer varying from 0 to p * -1, the image container Cl (i, q *) contains all the pixels the initial MAST master file of coordinates (x; y) such as:

il * <x <(i + 1) .l * q * .h * <y <q * .h * + s * • For i = p *, the image container Cl (p *, q *) contains all the pixels of the initial MAST master file with coordinates (x; y) such as:

p * I * <x <p * .l * + r * q * .h * <y <q * .h * + s *

Inside each of the image containers C1 (i, j), and still working from the group of received sub-images having the same values (DATE, NOMPLAN, PAGE), we integrate, by a call to by means of an HTLM tag, for example IMG, the image Sl (i, j) stored in the mass memory of the display device, retaining in R * the orientation it had in R and superimposing the pixel constituting its lower left corner in R to the pixel constituting the lower left corner of Cl (i, j) in R *.

An alternative implementation of this redialing protocol consists in generating, at the level of the row 2 container, column containers in place of row containers by working on "i" before working on "j". This variant ultimately leads to Cl (i, j) superimposable in R * on Cl (i, j) generated in the base case.

Ultimately, the object thus constituted at the level of the display device is a faithful representation of the MAST master file decomposed by the MO server having the same values (DATE, PLAN NAME, PAGE). Its height H * is equal to Hm, the height of the reference master MAST file; its width L * is equal to Lm, the width of the reference MAST master file. This object is also of the same RES resolution as the MAST master file. Each MAST master file induces for example the production of a particular HTLM page, and the HTML pages are linked to each other to produce a set of successive pages or else produces a single HTML page recording the P objects and allowing navigation between those -this. The source DOC_PDF source file, in PDF format and comprising several pages, is thus transformed into a set of corresponding pages, each consisting of the juxtaposition, when the web sub-display is displayed in 40, of matrix subimages corresponding to the cutting of the original PDF document page. Furthermore, as is known, the user can click on each of the portions of this reconstructed page, that is to say each sub-image of the corresponding MAST master file, and directly view the image which can be displayed in full. format because of the dimensions chosen for them as a function of the lowest common denominator among the screens of the display devices M1, ..., Mn.

In addition, each main container CP is identified by a unique triplet (DATE, NOMPLAN, PAGE) which characterizes it. The series of containers is called the set of main containers having the same parameter values "PLAN NAME", the name of this series of containers being this value "PLAN NAME".

The values of the parameters “DATE” and “PLAN NAME” thus make it possible to differentiate, on each of the display devices M1,.,. Μη, the containers generated from the elements of a new plan, from those generated from a plan relating to the updating of a series of plans. For this, and in the context of this preferred embodiment, it was chosen to compare the value “PLAN NAME” of the main container thus generated with all the names of the series of containers stored in the display device M1, ..., Mn .

If the value of the "PLAN NAME" parameter of the generated container is different from all the names of the series of containers known to the machine, the container is identified as being one of the pages of a new plan. He becomes the first in a series bearing his name.

If the value of the parameter "PLAN_NAME" of the container generated is identical to that of a series of containers already known to the machine, the container is identified as being the most up-to-date version of one of the pages of the plan corresponding to this series. We then compare the “PAGE” value of this container with all the page values of this series of containers. Either this “PAGE” value is different from all the “PAGE” values of the containers in the series (higher, logically): in this case, the generated container is identified as being a new page of the plan. Either this value “PAGE” is equal to a value “PAGE” that one or more containers of the series have: in this case, the container generated is identified as being the most up-to-date version of all the containers of the same value “PAGE " in the series. We can also verify, in the latter case, that the value "DATE" of the container generated is greater than all the values "DATE" of containers with the same value "DATE" in the series.

According to variant embodiments, version management can be carried out by other means such as counters or combinations of these means.

In the context of this preferred embodiment, the same resolution law is applied to the new versions of the pages of plans imported successively. This choice makes it possible to preserve the properties of the plan as much as possible, over time, as the versions change.

Ultimately, the recipient machine M1, ..., Mn is thus able to identify the most up-to-date versions of the different plan pages which are transmitted to it. These plan pages are communicated to him in a chosen format so that they can read and interact with them (here, a format consisting of main containers, containing line containers, containing image containers, containing images).

There has been described a visualization of the plan on the display devices M1, ..., Mn based on the production of an HTML document, stored in the mass memory of each device. This allows in particular to recompose the plan on the devices. The invention is not however limited to this type of redialing and display. In particular, tablets and smartphones allow dynamic display of images.

In addition, the display application allows you to save annotations linked to the plan. These annotations are linked to a position on the map and contain information, for example in the form of text, a photo and / or a voice recording, for example. These annotations can also be measurements made on the plane between two points. The scale of the plane is known by the link between the dimension of the plane and the resolution information RES. Thus, the resolution RES makes it possible to approximate physical dimensions of the paper plane, from measurements of distances between pixels made on the display devices M1, ..., Mn. Annotations and measurements are saved in the DOC_TXT file.

In another preferred embodiment, the containers are organized in Panels, namely:

• a main panel, in which there are Line Panels;

• said line Panels including Image Panels; and • said Image Panels calling the sub-images in PNG format saved in the memory of the device.

This embodiment is used for display on terminals of the tablet or smartphone type equipped for example with a Windows operating system. In this case, the commands for displaying the sub-images in PNG format are not stored in a file materialized as such, but are simply saved with a known address, in the RAM memory of the device. The set of sub-images assigned to a P object constitutes what can be called a "virtual" file. Here, the construction of the graphical interface is managed by the operating system which relies on a C # object dynamically created from the Panel constituting the main container. In particular, such an object is created on the fly as a function only of the images actually viewed on the screen, and is modified as soon as the user orders the viewing of at least one other image.

According to an alternative embodiment, the images corresponding to the oldest versions of plans are deleted from the memory of the display devices M1, ..., Mn, the latter therefore retaining only the most up-to-date version.

According to an additional characteristic, the MO server is capable of allowing the user to define a rectangular area, inscribed in the container CP materializing the digital plane. In this implementation, the user uses a computer configured to be able to communicate with the UNIX server via an Internet connection, in order to define a digital detail that the user wishes to extract. The proposed interface allows you to define a name: NOMZONE and coordinates: Xmax, Ymax, Xmin, Ymin, associated with the name of the plan displayed NAME PLAN. These parameters constitute a computer file called "zoning" (DOC_ZONE). The coordinates correspond to the definition of a rectangle, under part of the corresponding digital plane. The document FR 3 048 095 A1 details the process for defining and processing a sub-detail of the digital plane. This document is incorporated here by reference.

From the zoning file and the DOC_PDF source file, the MO server constitutes a second MAST2 master file corresponding to the zone defined by the DOC_ZONE zoning file. The resolution is determined according to the law of resolution. As the law is decreasing, and the sub-detail is smaller than the area covered by the digital plan, the resolution of the sub-detail is greater than or equal to that of the first MAST master file.

The second master file MAST2 is also transmitted to the display device M1, Mn which generates a second display file. In addition, the first visualization file is generated to incorporate a sub-detail access button.

The method allows the user, on these bases, to quickly access an advantageous reading of the sub-detail that he has isolated on MO. For this, the first DOC_HTML visualization file incorporates the digital button displayed on the screen of the visualization device at the user's disposal. This button bears for example the name of the zone (ZONE NAME). The user can click on this button using his mouse, for example, if the receiving device is a laptop equipped with a mouse, or press digitally on his screen, for example, if the receiving device is a smartphone equipped a touch screen, or a tablet equipped with a touch screen. The user will then automatically see the second display file DOC_HTML2 including the sub-detail centered and displayed in "full screen", built from the second master file MAST2 and with the improved resolution, in the rectangular display area of his screen. . Alternatively, or in addition, the display device automatically chooses the display of the second display file DOC_HTML2 if the displayed area is contained in the second display file DOC_HTML2, and the first display file DOC_HTML if the displayed area is outside the area covered by the second viewing file DOC_HTML2.

According to an alternative embodiment, when the source file DOC_PDF received leads to a division identical to that already carried out for the last version of the plan, the containers are therefore already appropriate, so that the update consists only in the change of link d image call from image containers. As a variant, a simple overwriting of the existing images makes it possible to update the plan while keeping only the updated version.

According to an alternative embodiment, when the source file DOC_PDF received leads to a division identical to that already carried out for the last version of the plan, the containers are therefore already appropriate, so that the update consists only in changing the sub-images having been the subject of a modification, from one version to another. The comparison of the sub-images with one another can be carried out at the level of the initial machine MO so that only the sub-images exhibiting a modification are then broadcast to the entire system. This embodiment makes it possible to reduce the volume of data to be transferred, to reduce the computing times on the terminals M1, ..., Mn, and to preserve the memory capacity of the machines.

According to an additional characteristic, the display device is designed to zoom in on an area of the plan, with a user interface known per se. In this embodiment, provision can be made to limit the zoom out in order to display at most only a partial area of the plan. In this case, even the initial view of the visualization file shows only a partial area of the plan.

In another embodiment, the server produces a first MAST master file as described above, and at least a third MAST3 master file covering the same area as the first MAST master file and with a third resolution greater than the first resolution. The third master file MAST3 is used to generate a third display file DOC_HTML3 associated with the third master file MAST3. The visualization device is intended to define a sub-part of the plan as a working area, in a similar manner to the definition of the zoning file described above. From the dimensions of the work area, a target resolution is determined according to the law of resolution.

The display device reviews the display files DOC_HTML, DOC_HTML3, corresponding to the same plane, but at different resolutions. It then searches the resolutions for one that is just less than or equal to the target resolution and selects the display of the selected area from the visualization file corresponding to the resolution. For example, if the visualization files are provided with respective resolutions of 75,100,150 and 200 dpi, and the target resolution is set to 140, the display device will select the visualization file with a resolution of 100 dpi.

The previously described processing implemented on the MO server could be distributed on different machines, and possibly on one or other of the display devices if this device has the necessary tools, algorithms and computing power. Similarly, the display file can be prepared by the server MO before it is transferred to the various display devices M1, ..., Mn.

The MO server can also be a virtual server hosted on a server farm.

According to an alternative embodiment of the method, the source file loaded by the user can be in DWG (Autocad) format. In this case, the MO server has a toolbox allowing this source document to be transformed into one or more pixelated PNG flat images. This toolbox can for example be RealDWG. In this case, the plan pages can be the different tabs of the DWG document.

According to an alternative embodiment of the method, the source file loaded by the user can be a three-dimensional model representing an object constructed or to be constructed. Within the framework of this variant embodiment, the MO server has a toolbox making it possible to extract flat and pixelated images of this model, possibly by means of a specific graphic interface, available on the MO server and making it possible to position selected cuts.

Claims (7)

claims 1. Method for processing a view of a digital plane by at least one computer display device (M1, Mn), connected through a computer network to a computer device forming a server (MO), method according to which; • we receive on the server (MO) a source file (DOC_PDF) coding the digital plan, • we produce from the source file (DOC_PDF) at least one master file (MAST, MAST2, MAST3) comprising a matrix image of at minus part of the digital plane and resolution information (RES) indicating the resolution of the image; • for each master file (MAST, MAST2, MAST3), a visualization file (DOC_HTML) is constructed from said master file (MAST, MAST2, MAST3); • the display file (DOC_HTML) is stored in a memory of the display device (M1, Mn) and it is displayed on a screen of said device; characterized in that, for the production of a first of the master files (MAST) covering a first height and a first width, the resolution is determined according to a law of decreasing resolution as a function of a dimension of the master file (MAST) and the image of the master file is generated with said resolution, the dimension being chosen from a group comprising the first width, the first height and the product area of the first width and the first height. 2. Processing method according to claim 1, according to which, after reception of the source file (DOC_PDF), at least one zoning part included inside the first master file (MAST) is defined and a second of the files is constructed. masters (MAST2) corresponding to this zoning part, the image of the second master file (MAST2) is generated with a resolution determined according to the law of resolution applied to the zoning part, and a second visualization file (DOC_HTML2) is generated corresponding to the second master file (MAST2), the display device (M1, Mn) making it possible to choose which of the display files (DOC_HTML, DOC_HTML2) is displayed. 3. Processing method according to claim 2, in which one chooses the display on the display device (M1,, Mn) of the second display file (DOC_HTML2) if the displayed area is contained in the second display file (DOC_HTML2 ), and the first display file (DOC_HTML) if the displayed area is outside the area covered by the second display file (DOC_HTML2). 4. Processing method according to claim 1, in which at least a third master file (MAST3) is produced covering the same area as the first master file (MAST) and with a third resolution greater than the first resolution, the third is generated. visualization file (DOC_HTML3) associated with the third master file (MAST3), a sub-part of the plan is defined as the working zone, a target resolution is determined according to the law of resolution applied to the working zone and a part is displayed at less of the work area with the visualization file (DOC_HTML, DOC_HTML3) whose resolution is just less than or equal to the target resolution. 5. Treatment method according to one of the preceding claims, according to which, the display device (M1, ..., Mn) is intended to zoom in on an area of the map, the zoom out is limited so as not to display at more than a partial area of the plan. 6. Processing method according to one of the preceding claims, in which at least two intermediate files (DOC_PNG1, ... DOC_PNGP) are produced from the master file (MAST), each intermediate file (DOC_PNG1, .. . DOC_PNGP) comprising a matrix image resulting from a series of matrix images obtained by cutting out the matrix image of the master file (MAST) and at least one resolution item of information (RES) corresponding to the resolution of the master file (MAST) , the intermediate files (DOC_PNG1, ... DOC_PNGP) used for the construction of the visualization file (DOC_HTML) associated with said master file (MAST). 7. System for processing a view of a digital plan comprising a computer device forming a server (MO), at least one computer display device connected to the server (MO) through a computer network, the server (MO) being configured to receive a source file (DOC_PDF) encoding the digital plane, producing from the source file (DOC_PDF) at least one master file comprising a raster image of at least part of the digital plane and resolution information (RES) indicating the resolution of the image, and for each master file, construct a display file (DOC_HTML) from said master file, the display device (M1, ..., Mn) being configured to receive the display file ( DOC_HTML) through the communication network and comprising a memory for storing the display file (DOC_HTML) and a screen for displaying the display file (DOC_HTML); characterized in that, for the production of a first of the master files covering a first height and a first width, the server (MO) is configured to determine the resolution according to a law of decreasing resolution as a function of a dimension of the master file and generating the image of the master file with said resolution, the dimension being chosen from a group comprising the first width, the first height and the product area of the first width and the first height.