JP4345985B2 - Image display processing device - Google Patents

Description

  The present invention relates to an image display processing device that displays a map image and an aerial photograph image using a viewer function of a small portable information terminal device (information processing terminal) such as a PDA or a notebook PC.

For example, an image display processing device that executes processing for drawing and displaying a map image on a display device is known. Such an image display processing device generally has a map image scrolling function. Scrolling refers to displaying a desired place by moving a map image two-dimensionally up and down and left and right on the screen display. As an example of such an image display processing device, for example, Patent Document 1 (Japanese Patent Laid-Open No. 2000-111151) stores a plurality of image data of a plurality of levels with different data amounts for an image of the same object. A data reading unit for reading requested image data from a database and storing it in a memory; a data requesting unit for requesting the data reading unit for the plurality of levels of image data describing a designated display area; A drawing unit that reads out image data describing the display region and draws an image of the display region, and the data request unit converts low-level image data with a small amount of data into a larger amount of the data. An image display device that requests the data reading unit to read before high-level image data is disclosed.
JP 2000-11115 A

  In general, in the image display processing apparatus as described above, the processing of drawing a map is very heavy. For example, when displaying an image, it is necessary to read the data of the target image from the data storage device in advance, and when reading data from a low-speed device, it takes a considerable reading time. For this reason, even if the display image is switched at high speed, it takes time to read the next image data, and the next image is not displayed at high speed. Also, if you are storing huge image data divided into a large number of data, if you try to scroll the screen or enlarge / reduce the display magnification with a part of the huge image data displayed on the screen, In the same manner as the image switching, the data reading operation for the next part occurs. Due to the waiting time for reading this data, high-speed scrolling and scaling cannot be performed. In this case, it appears that the scrolling and scaling operations have stopped on the display device, and the user feels a lot of stress when using the device. Such a problem is particularly noticeable in PDAs and small notebook PCs, which are small portable information terminals with poor operating performance, and has been a problem.

In order to solve such problems, the invention according to claim 1 is an apparatus that includes a CPU and operates by a system program , manages geospatial information of the same object in a plurality of hierarchical structures, and is selected by a user. In the image display processing apparatus for displaying a part of the geospatial information on the display screen, the hierarchical structure is composed of layers having different information densities, and the layer divides the geospatial information into a plurality of rectangles. composed of rectangular image data comprising Te, prepared rectangle index data that holds the index data of the rectangular image data when displaying a partial area of the geospatial information that the user has selected the display screen, the display The overlap area ratio indicating the degree of overlap between the display area of the screen and the rectangular image data, and the average of the layer unit of information density of the rectangular image data overlapping the rectangle of the display area The score of each layer is calculated based on the information density ratio obtained by adjusting the quotient divided by the information density of the above to a ratio with a predetermined threshold and the specific gravity of the layer whose base number is a power according to the information density of the layer Which layer of the plurality of layers is to be displayed is determined .

  The invention according to claim 2 is the image display processing device according to claim 1, wherein the rectangular shape of the rectangular image data is arbitrary.

The invention according to claim 3 is the image display processing device according to claim 1 or 2 , wherein the score is (score) = (overlapping area ratio) × (information density ratio) / (layer specific gravity). ).

According to a fourth aspect of the present invention, in the image display processing device according to any one of the first to third aspects, a pair of rectangular index data and rectangular image data is stored for display on the display screen. A memory having a plurality of basic areas is used.

The invention according to claim 5 is the image display processing device according to claim 4 , wherein the basic area counts how many times the stored pair of rectangular index data and rectangular image data is used. Is provided.

According to a sixth aspect of the present invention, in the image display processing device according to the fourth or fifth aspect, the basic display that needs to be rewritten out of a plurality of basic areas of the memory when displaying on the display screen. It is characterized by rewriting only the area.

According to a seventh aspect of the present invention, in the image display processing device according to the sixth aspect , the rewrite order when rewriting the basic area of the memory is the basic area for holding the rectangular image data outside the display screen, the display It is characterized in that the order is a basic area for holding rectangular image data of a layer different from the layer to be tried, and a basic area for holding rectangular image data with a small number of counts by a counter.

The invention according to claim 8 is the image display processing device according to any one of claims 1 to 7 , wherein the geospatial information is mesh data.

The invention according to claim 9 is the image display processing device according to any one of claims 1 to 7 , wherein the geospatial information is vector data.

The invention according to claim 10 is the image display processing device according to any one of claims 1 to 7 , wherein the geospatial information is mesh data and vector data.

  According to the image display processing apparatus of the present invention, due to the simplicity and independence of the basic components (rectangular image data, rectangular index data), the substance of the information structure can be mass-produced at low cost, and various types of information can be obtained. It can respond flexibly. Further, according to the image display processing device of the present invention, appropriate information (rectangular image data of an appropriate layer) corresponding to the position and range of interest is selected and displayed from a large amount of position and shape information. Therefore, the user is always provided with sufficient information as necessary. Since the switching control mechanism (scoring method by score) selects and displays appropriate information according to the position and range of interest, information can be provided to the user without stress. In scoring, the use of a non-linear evaluation formula increases the possibility that a higher layer will be displayed, and the effect of making it difficult to display a blank on the screen is obtained. Further, according to the image display processing apparatus of the present invention, a smooth display corresponding to an enlargement / reduction / movement operation can be performed even in an information processing apparatus having relatively low performance such as a small portable information terminal device such as a PDA or a notebook PC. Is possible. In addition, according to the image display processing apparatus of the present invention, the information structure and its processing mechanism take into account margins at key points in order to allow ambiguity, and as a result, include other programs, apparatuses, and methods. Can be realized.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The image display processing device according to the embodiment of the present invention relates to processing for efficiently displaying digital image information such as a map and a graphic in a virtual plane area (window or view) of the information processing device. FIG. 1 is a schematic configuration diagram of an entire system of an image display processing apparatus according to an embodiment of the present invention. The main body of the image display processing device system according to the present invention is assumed to be constructed by a small portable information terminal device such as a PDA (Personal Digital Assistant), a notebook PC (Personal Computer), etc. Although the best results are obtained when the present invention is applied to a portable information terminal device, the present invention is not necessarily applied to a small portable information terminal device or the like. It can also be applied to information equipment.

  In FIG. 1, 10 is a system bus, 11 is a CPU (Central Processing Unit), 12 is a RAM (Random Access Memory), 13 is a ROM (Read Only Memory), and 14 is a communication control unit that controls communication with an external information device. 15 is an input control unit such as a keyboard controller, 16 is an output control unit such as a display controller, 17 is an external storage device control unit, 18 is an input unit including input devices such as a keyboard, pointing device, and mouse, 19 is an LCD display, etc. An output unit 20 including a display device and a printing device 20 is an external storage device such as an HDD (Hard Disk Drive).

  In FIG. 1, the CPU 11 retrieves and acquires data by communicating with an external device in accordance with a program ROM stored in the ROM 13 or a program stored in the large-capacity external storage device 20. Processing of output data in which graphics, images, characters, tables, etc. are mixed is executed, and management of a database stored in the external storage device 20 is further executed.

  Further, the CPU 11 comprehensively controls each device connected to the system bus 10. The program ROM in the ROM 13 or the external storage device 20 stores an operating system program (hereinafter referred to as OS) that is a basic program for controlling the CPU 11. The ROM 13 or the external storage device 20 stores various data used when performing output data processing or the like. The RAM 12 functions as a main memory and work area for the CPU 11.

  The input control unit 15 controls the input unit 18 from a keyboard or a pointing device (not shown). The output control unit 16 controls output of a display device such as an LCD display and a printing device such as a printer.

The external storage device control unit 17 is an external storage such as an HHD (hard disk drive) that stores a boot program, various applications, font data, user files, editing files, a printer driver, or a flexible disk (FD) in some cases. The access control to the device 20 is also controlled. The communication control unit 14 controls communication with an external device via a network, whereby the data required by the system is transferred to an external device on the Internet or an intranet. It is configured so that it can be acquired from a database it holds or information can be transmitted to an external device.

  In the external storage device 20, in addition to an operating system program (hereinafter referred to as OS) which is a control program of the CPU 11, a system program of the image display processing device of the present invention, a database used in this program, and the like are installed, stored and stored. .

  Next, the hierarchical structure in the geospatial information of the image display processing device according to the embodiment of the present invention and the concept of the rectangular image data (and the rectangular index data that is the index) constituting each layer will be described. The basic unit of geospatial information is rectangular image data divided into rectangles, and a plurality of these forms a single layer. In the layer, several layers from a layer having a high information density to a layer having a low information density have a hierarchical structure.

  The present invention is supposed to be used for a map viewer in a small portable information terminal device (information processing terminal) such as a PDA or a notebook PC. In a viewer in such a small portable information terminal device, display processing such as enlarging / reducing a desired location on a map that the user wants to refer to or moving by scrolling must be performed. Such display processing must be performed instantaneously so as not to cause the user to feel stress. In small portable information terminal devices, the power of the mounted CPU is also limited due to power consumption problems and restrictions on the space in the device casing, and therefore complicated processing such as image processing requires processing time. This is usually the case. The present invention stresses the user even in a small portable information terminal device by selecting the optimum layer for display in a viewer in the small portable information terminal device from the rectangular index data constituting each layer of the above hierarchical structure. It is intended to perform high-speed scrolling and high-speed enlargement / reduction that can not be felt. For this reason, in the present invention, rectangular index data is used as an index of actual data.

  FIG. 2 is a diagram showing the concept of rectangular index data in the image display processing device according to the embodiment of the present invention. Index data for rectangular image data (hereinafter also referred to as “actual data” or “geospatial information body”) obtained by extracting one rectangular portion of the plane orthogonal coordinate system as shown in FIG. As (index data), rectangular index data is defined and is a basic unit of an information structure in the image display processing device according to the embodiment of the present invention. Such rectangular index data can be easily grasped or calculated in terms of a positional relationship on a plane, and thus is convenient. The rectangular index data is separated from rectangular image data (actual data) having a relatively large amount of information.

  The rectangular index data and the rectangular image data (actual data) have the following characteristics. Certain rectangular index data has no direct relationship with other rectangular or rectangular image data (actual data) other than the relationship with the rectangular image data (actual data) (bidirectional relationship based on the identifier). In addition, the rectangular index data is not limited to indexing rectangular image data obtained by extracting one rectangular portion of the plane orthogonal coordinate system as shown in FIG. 2, that is, there are restrictions such as the size of the rectangle and the aspect ratio. Absent. That is, the rectangular image data can have any aspect ratio and size as long as it is rectangular. In addition, there may be partial overlap between a plurality of pieces of rectangular image data in the entire geospatial information. (The overlap may be up to about 30% in terms of area.) In addition, the relationship between the rectangular index data and the actual data does not necessarily require strictness, and the relationship between the rectangular index data and the actual data is overall. The relationship allows for ambiguity. By such simplicity and independence, free arrangement and free stratification of rectangular index data is realized. The rectangular index data is convenient when processing geospatial information such as aerial photographs, ground photographs, maps, facility layout diagrams, and ledgers.

  In addition, when expressing geospatial information related to topographic maps such as aerial photographs, ground photographs, maps, and facility layout maps, generally used data formats include vector data and mesh data (digital image data). The geospatial information in the present invention includes both types of data. Whether geospatial information is vector data or mesh data can be selected depending on the application, but when handling image data with different scales, vector data is easy to use, Mesh data (digital image data) is convenient for superposition. In the present invention, vector data and mesh data (digital image data) can be mixed. In the concept of “layer” described later, mesh data (digital image data) such as digital aerial photographs is prepared in one layer, and vector data such as digital topographic maps is stored in another layer. Thus, mesh data (digital image data) and vector data can be mixed and used. At this time, in the case of mesh data (digital image data), the concept of “pixel” is used, and in the case of vector data, the concept of “scale” is used.

  As shown in FIG. 2B, the components of the rectangular index data constitute an identifier (name or ID) of the rectangular index data, level information of the layer to which the rectangular image data belongs, and rectangular image data (actual data). Position coordinate information (the position of the upper left point and the position of the lower right point in the corresponding coordinate system), pointers (file names and addresses) to actual data (graphics, images, DB) corresponding to rectangles, information density of actual data Information (number of pixels for images, scale for graphics, etc.). Note that the rectangular image data is parallel to the orthogonal coordinate axes in order to simplify the geometric calculation.

  Next, how to divide the entire geospatial information constituting one layer into rectangular image data (actual data) will be described. Dividing relatively large data into units optimal for the system (system) in which the image display processing apparatus of the present invention operates is referred to as normalization division here. When dividing the entire geospatial information into rectangular image data, the division format is arbitrary, but uniformity of the data amount corresponding to the shape of the rectangular image data is desired. Note that the normalization division is a selection item and not an essential item.

Next, how the divided rectangular image data (actual data) is arranged in the entire geospatial information constituting one layer will be described. FIG. 3 is a diagram showing an arrangement example of rectangular image data in the image display processing device according to the embodiment of the present invention. The arrangement of the divided rectangular image data (actual data) is not particularly limited in the number, size, aspect ratio, and positional relationship of the rectangular image data. Should be avoided as much as possible. (If the overlapping rate is within 30%, the operation of the image display processing apparatus of the present invention is not greatly affected.) In each of (A) to (E) of FIG. A rectangular area indicated by a solid line is rectangular image data (actual data).
FIG. 3A shows rectangular image data (actual data) arranged in a grid pattern, and is suitable for expressing the entire image evenly. Further, FIG. 3B is a diagram in which rectangular image data (actual data) is continuously arranged. For example, when the image data is a ground photograph or a map, a flow of a river or a main trunk road is displayed. Suitable for expressing. FIG. 3C shows rectangular image data (actual data) arranged in a distributed manner. For example, when the image data is a map, it is suitable for expressing major cities and the like. FIG. 3D shows rectangular image data (actual data) freely arranged. FIG. 3E shows a mixed arrangement in which rectangular image data (actual data) is combined with a grid arrangement, a continuous arrangement, and the like.

  Next, the format for storing the rectangular index data and the rectangular image data (actual data) will be described. As the storage format, a plurality of sets of rectangular index data files and rectangular image data (actual data) files are prepared and stored. Format, a method of preparing and storing a plurality of sets of rectangular index data and rectangular image data (actual data) as one file, and a format of storing a plurality of sets of rectangular index data and rectangular image data (actual data) as one file. is there.

  Next, the concept of the hierarchical structure in the geospatial information of the image display processing device according to the embodiment of the present invention will be described. FIG. 4 is a diagram showing an image of the concept of the hierarchical structure of the image display processing device according to the embodiment of the present invention. As described above, a layer is an aggregate of a plurality of divided rectangular image data, and several layers from a layer having a high information density to a layer having a low information density have a hierarchical structure. In principle, as shown in FIG. 4, the information density is set to increase from the upper layer to the lower layer. There is no relationship between the layers other than the positional relationship on the plane.

  As shown in FIG. 4, a group of basic unit rectangular image data (or rectangular index data as index data thereof) constitutes a layer. The number of layers can be freely set from 1 to n, and is classified according to characteristics of actual data (data type, resolution, scale, etc.) and distributed to each layer. Further, by unifying information density standards, real data having different characteristics can be mixed in each layer or in the same layer. (A mixture of image data and vector graphic data, etc.) As shown in FIG. 4, the highest layer is defined as a level 0 layer, and the lowest layer is defined as a level n layer. As shown in the figure, the information density is higher in the lower layer (level n than level 0).

  The storage format of the layers can be a storage format of a group of basic units (single file or a plurality of files) in each layer folder, or a storage format of one file including a folder of layers.

  Next, some examples of layer classification based on rectangular image data will be described. 5 to 7 are diagrams showing a hierarchical structure depending on rectangular image data of the image display processing device according to the embodiment of the present invention. In each of FIGS. 5 to 7, (A) shows a level 0 layer, (B) shows a level 1 layer, and (C) shows a level 2 layer. (That is, the information density of (C) is the highest among (A) to (C) in all the drawings of FIGS. 5 to 7.) In addition, in each of FIGS. 5 to 7, rectangular regions indicated by dotted lines Indicates the entire geospatial information, and a rectangular area indicated by a solid line is rectangular image data (actual data).

  In FIGS. 5A to 5C, rectangular image data is arranged in a grid pattern in all levels of layers. According to such a grid arrangement, an image pyramid as described in FIG.

  FIGS. 6A to 6C show an example in which high-resolution rectangular image data is partially arranged in each level layer. In the level 0 layer in FIG. 6A, the entire geospatial information is composed of one piece of rectangular image data, and the resolution is 600 × 800 dots. In the level 1 layer of FIG. 6B, the resolution of 600 × 800 dots is the same for both the half-divided image and the quarter-divided image, and the latter is naturally higher in information density. As described above, in the image display processing apparatus of the present invention, various types of rectangular image data can be mixed even in layers having the same level, with different information densities. In the level 2 layer in FIG. 6C, the image further finely divided has a resolution of 600 × 800 dots.

    FIGS. 7A to 7C show examples in which rectangular image data of layers at respective levels are classified by scale. In the level 0 layer shown in FIG. 7A, the rectangular image data has a general shape, and its scale is set to, for example, 1: 5000 level. In the level 1 layer shown in FIG. 7B, the average rectangular image data indicates the reference shape, and the scale is set to, for example, 1: 1000 level. In the level 2 layer of FIG. 7C, the rectangular image data is such that it shows a partial detailed shape, and its scale is set to, for example, 1: 200 level. The hierarchical structure as shown in FIG. 7 is convenient when handling geospatial information such as maps and ground photographs.

  Next, in the image display processing apparatus of the present invention, a method for selecting an image of an optimum layer to be displayed on the window display or the view display of the output unit 19 such as a display display apparatus will be described. FIG. 8 is a diagram illustrating the concept of optimum layer selection in the image display processing device according to the embodiment of the present invention. In FIG. 8, a virtual plane area (also referred to as “window” or “view”) is a part of the entire area of the geospatial information, and is displayed on the display display device of the image display processing device by the user. This is the area you are trying to make. In the image display processing device of the present invention, when such a virtual plane area is displayed, it is possible to cause the user to feel stress even in a small portable information terminal device by using the concepts such as the hierarchical structure and the rectangular index data. There is no fast scrolling or fast scaling.

  FIG. 8 shows an image of exploring each layer by penetrating from the highest layer (level 0) to the lowest layer (level 5) with a rectangle in the virtual plane region. “Exploration” is a word used for the purpose of facilitating the physical description of the present invention. As an algorithm for selecting an optimal display layer of a specific image display processing apparatus according to the present invention, first, a virtual plane Pick up the rectangular index data in each layer penetrated by the rectangle of the region. Next, a predetermined calculation is performed for each layer based on the rectangular index data picked up by each layer. As a result of this calculation, the layer having the highest score among the layers from the highest layer to the lowest layer is selected as the optimal layer for display.

  The image of the rectangle index data in each layer penetrated by the rectangle of the virtual plane area is as shown in FIG. FIG. 9 is an image of the relationship between the virtual plane area and the rectangular index data in the predetermined level layer in the image display processing device according to the embodiment of the present invention. In FIG. 9, rectangular index data indicated by shading (when the rectangular portion is regarded as “image data”, it becomes “rectangular image data” instead of “rectangular index data”. Since calculation is performed, it is assumed that “rectangular index data” is used here.) Is data that is penetrated by a rectangle of the virtual plane area (overlaps with the virtual plane area).

  In the example of FIG. 8, when a rectangle of a certain virtual plane region is selected, the predetermined calculation results are as follows: layer (level 0) = 2.561 points, layer (level 1) = 0.811, layer (level 2) ) = 0.849 points, layer (level 3) = 3.102 points, layer (level 4) = 0.067 points, layer (level 5) = 0.002 points, from the top layer (level 0) The layer (level 3) having the highest score among the lowest layers (level 5) is selected.

  As described above, the optimum layer selection method in the image display processing apparatus according to the embodiment of the present invention is summarized. The optimum layer selection algorithm is activated when an event (movement, enlargement, reduction) of the virtual plane area occurs. Is done. Then, the rectangular index data in which the regions overlap is obtained by penetrating from the highest layer to the lowest layer in the rectangle of the virtual plane region. Next, by scoring the appropriateness of the layer with respect to the virtual plane region, the optimum layer is specified. It should be noted that such an image processing method (optimum layer selection method) used in the present invention is based on an image in which hierarchical information is operated so as to examine the state by boring the formation. It is sometimes called the drilling exploration method.

  Next, a scoring method when selecting an optimum layer in the image display processing apparatus of the present invention will be described. In the scoring of the image display processing apparatus of the present invention, special parameters such as “overlapping area ratio”, “information density ratio”, and “layer specific gravity” are used. FIG. 10 is a diagram for explaining calculation of the overlapping area ratio in scoring in the image display processing device according to the embodiment of the present invention.

  The “overlapping area ratio” is a value obtained by dividing the sum of the layer units of the area of the overlapping area of the rectangle of the virtual plane area and the rectangular index data in a certain layer by the area of the rectangle of the virtual plane area. In the example of FIG. 8, in the case of FIG. 8A where the layer level is A, the overlapping area ratio is 1, and in the case of FIG. 8B where the layer level is B, the overlapping area ratio is It shows that it is 0.3.

  Next, “information density ratio” in scoring of the image display processing apparatus of the present invention will be described. FIG. 11 is a diagram showing a calculation flow of the overlapping information density ratio in scoring in the image display processing device according to the embodiment of the present invention. The information density ratio is a value obtained by adjusting a quotient obtained by dividing an average of information density layer units of rectangular image data overlapping a rectangle of the virtual plane area by the information density of the virtual plane area with a threshold value. Here, it has been found from an empirical rule that an effective layer can be selected by using a value of about 2.0 to 4.0.

  In FIG. 11, when a calculation flow routine is started in step S100, (layer density average of information density) / (information density of virtual plane region) is calculated in step S101. Next, in step S102, it is determined whether the quotient calculated in step S101 is greater than a threshold value. If it is determined that the value is large, (information density ratio) = (threshold value) / quotient is calculated, and the process proceeds to step S105 and ends. If the determination result in step S102 is No, the process proceeds to step S104, (information density ratio) = quotient / (threshold) is calculated, and the process proceeds to step S105 and ends. In the flow of FIG. 11, whether to calculate by (information density ratio) = (threshold) ÷ quotient or (information density ratio) = quotient ÷ (threshold) is the above “adjustment”. Applicable. When the quotient is the same value as the threshold value, the ideal value is 1.0. Whether the quotient is larger or smaller than the threshold, the ratio is smaller than 1.0, and the closer the quotient is, the closer to 0.0.

  FIG. 12 is a diagram for explaining a calculation example of the information density ratio in the image display processing apparatus of the present invention. For example, FIG. 12 assumes a case where geospatial information of a ground photograph is handled, and how many meters corresponds to the pixel size of the display device is a measure of information density. In FIG. 12, from the layer (level 0) to the layer level (level 4), it was assumed that “average pixel size” and “view pixel size” are as shown in the figure. Further, the information density was calculated as the resolution of the image data, and the threshold value was set as 3.0.

  Next, “layer specific gravity” in scoring of the image display processing device of the present invention will be described. FIG. 13 is a diagram for explaining the specific gravity of layers in scoring in the image display processing device according to the embodiment of the present invention. The specific gravity of the layer is a value obtained by raising the base number (standard value is route 2) to the power of the number of layer levels (the highest is 0 and the value is gradually increased by 1). The effect of the “specific gravity of the layer” on the scoring of the image display processing device of the present invention will be described later.

  Next, a calculation formula for scoring in the image display processing apparatus of the present invention will be described. The score of each layer in the present invention is obtained by calculating by the following equation using the values of “overlapping area ratio”, “information density ratio”, and “layer specific gravity” described so far.

(Score) = (Overlapping area ratio) x (Information density ratio) ÷ (Layer specific gravity)
According to such a score calculation formula, the distribution of scores can be adjusted by changing the threshold of “information density ratio” and the basis number of “layer specific gravity”. FIG. 14 is a diagram for explaining a score calculation example in the image display processing device according to the embodiment of the present invention. In the score calculation example in FIG. 14, the score for the layer (level 1) is the highest, and therefore the layer (level 1) is determined to be the optimal hierarchy.

  Here, the effect of “layer specific gravity” in scoring the image display processing device of the present invention will be described. Hereinafter, as a basic premise for explaining the effect of the specific gravity of the layer, FIG. 15 is a diagram showing preconditions for explaining the effect of the “specific gravity of the layer”. As a precondition, data constituting an image pyramid as shown in FIG. That is, the layer (level 0) constitutes the entire geospatial information as one rectangular image data. Further, the layer (level 1) divides the entire geospatial information vertically and horizontally into four rectangular image data, and the layer (level 2) divides the entire geospatial information into four vertically and horizontally and has 16 rectangular image data. In the layer (level 3), the entire geospatial information is divided into 8 parts in length and breadth, and each piece is composed of 64 pieces of rectangular image data. Also in this example, image data of a ground photograph is assumed, the pixel size of the layer (level 0) is 8 m at the ground resolution, the pixel size of the layer (level 1) is 4 m at the ground resolution, and the pixel of the layer (level 2) The size is 2 m at the ground resolution, and the pixel size of the layer (level 3) is 1 m at the ground resolution. As another precondition, it is assumed that the rectangular image data always covers the view (virtual plane region) region in all layers, and the “overlapping area ratio” is always 1.0. The threshold for calculating the “information density ratio” is 2.0.

In the above preconditions, (the specific gravity of the layer) is not taken into account (score) = (overlapping area ratio) x (information density ratio)
FIG. 17 is a graph showing changes in values with respect to enlargement / reduction of the view of each layer. FIG. 16 shows a table used for graphing in FIG. 17, and the pixel size of the view is changed to “1”, “2”, “4”, “8”, “16”, “32”. The score at each layer (level) is calculated.

  In FIG. 17, the horizontal axis indicates the view pixel size (unit: m), and the vertical axis indicates the score. The view is enlarged (narrow range) as the horizontal axis is closer to 0 (left side), and the view is reduced (wide range) as the value on the horizontal axis is large (right side).

Since the “overlapping area ratio” is assumed to be 1.0 as described above, the change in the score is a change of the “information density ratio” itself, and the calculation method of the “information density ratio” (existing) is ( Quotient) = (view pixel size) / (layer pixel size)
If (quotient)> (threshold), calculate by (information density ratio) = (threshold) ÷ (quotient)
In the case of (quotient) ≦ (threshold value), the calculation is performed by (information density ratio) = (quotient) / (threshold value). Reaches a maximum score of 1.0 at a position of 16m.

  Since the “threshold” is 2.0, a sufficient image resolution can be obtained for the view, but it always works excessively at the transition point where the layers are switched. (The lower layer is likely to be adopted.) In addition, there are two transition points (points where lines intersect in the graph) where the layers switch at the same horizontal axis position, which may impair the consistency or consistency of judgment. There is sex. In addition, the presence or absence of the maximum value (optimum value) and the transition point at the same horizontal axis may disturb the consistency or consistency of determination.

  The above is the problem that occurs when the concept of “specific gravity of layer” is not introduced. The following case also shows the problem when scoring without using “specific gravity of layer”. In the example shown in FIG. 18, when the “overlapping area ratio” is 1.0 for each layer, the view pixel size is 4.508 m, and the threshold value is 2.0, the layers (level 0) to the layers ( Level 3) is scored.

  In the case of FIG. 18, the optimum layer is determined to be a layer (level 2), but the score difference from the layer (level 1) is only 0.08, and the layer (level 1) is displayed in the view. The resolution of the resulting image is almost the same as when using the layer (level 2). When covering the same view area (area), the layer (level 2) requires a larger amount of data than the layer (level 1), and as a result, occupies more memory area such as the system RAM.

As described above, it is possible to reduce the occupation or consumption of the storage area (eg, physical memory) of the image display processing device system by selecting the uppermost layer as possible as the optimum layer.
(2) The occupation or consumption amount of the storage area of the image display processing device system can be suppressed to a certain amount.
(3) Since there is a high possibility that the upper layer covers the whole, it is difficult to generate a blank on the view.
Although it is preferable for such reasons, the following formula does not take into account (specific gravity of the layer) (score) = (overlapping area ratio) × (information density ratio)
When the score is calculated by the following formula, various problems as described above occur.

Therefore, taking into account the concept of “layer specific gravity”
(Score) = (Overlapping area ratio) x (Information density ratio) ÷ (Layer specific gravity)
FIG. 20 is a graph showing changes in values for the view enlargement / reduction of each layer under the preconditions of FIG. FIG. 19 shows a table used for graphing in FIG. 20, and the view pixel size is changed to “1”, “2”, “4”, “8”, “16”, “32”. The score at each layer (level) is calculated. As can be seen from FIG. 20, when the “specific gravity of the layer” is taken into consideration when calculating the score, the following tendency appears.
・ Since the lower layer, the highest score is lower, so the intersection where the layer changes moves to the left.
・ The tendency to adopt higher ranks will increase.
-Certainty is guaranteed when lower layers should be adopted.
Due to this tendency, the introduction of “layer specific gravity” can reduce the burden on the image display processing system.

  FIG. 21 shows that when the “overlapping area ratio” is 1.0 for each layer, the pixel size of the view is 4.508 m, and the threshold value is 2.0, the layers (level 0) to the layers of the preconditions (FIG. 15) described above. (Level 3) is scored. Unlike FIG. 18, in the case of FIG. 21, the score of 0.497 is the highest and the layer (level 1) is selected.

Overall, the effect of introducing the “layer specific gravity” when calculating the score is:
・ “Specific gravity of layer” does not work strongly in the entire view state, but works gently in a narrow transition region.
-“Layer specific gravity” has limited effect on idealized data (eg, image pyramid).
• “Specific gravity of layer” exhibits an effect of suppressing excessive layer switching in freely configured data (eg, distributed index arrangement, discontinuity of resolution difference between layers, etc.).
Etc.

  Next, a method of using a memory in the image display processing device according to the embodiment of the present invention will be described. FIG. 22 is a diagram showing a usage image of the memory in the image display processing device according to the embodiment of the present invention. As the memory described here, a part of the above-described RAM 12 may be allocated and used, or may be newly provided on the system bus 10. Also, in the method of using the memory in the image display processing apparatus of the present invention, it is sometimes referred to as a deposition memory because it is used to deposit information in the memory.

  As shown in FIG. 22, the accumulation memory is located between the hierarchical information structure of the rectangular index data group and the virtual plane area display of the image display processing device, and manages efficient transfer of actual data. Further, the accumulation memory has a plurality of memory areas which are partitioned basic units, and stores and holds a limited number of rectangular index data and rectangular image data across the layers.

  FIG. 23 is a diagram showing a usage image of the memory area in the system of the image display processing device according to the embodiment of the present invention. As shown in FIG. 23, the memory area which is the basic unit of the accumulation memory is configured to store both data while maintaining the bidirectional relationship between the rectangular index data and the rectangular image data (actual data). Is done. The memory area is further provided with a usage counter, which logs how many times the rectangular image data (actual data) stored in the memory area has been used. When the memory area is released and new rectangular index data and rectangular image data (actual data) are stored, it is reset to zero. Further, the size of the basic unit of the accumulation memory is assumed to be about the same size as one unit of rectangular image data (actual data) obtained by normalization division. That is, as shown in FIG. 23, one memory area has a storage capacity enough to record a pair of roughly rectangular index data and rectangular image data (actual data). Moreover, it is preferable to set the limit of the accumulation memory (number of basic units) according to the performance of the information processing terminal used as the system of the image display processing apparatus of the present invention. Performance) can be used efficiently. In order to keep the number of memory areas within a range that does not occupy the resources of the image display processing device system, it is preferable to use a limited number (usually about 4 to 9). Normally, for each view event, four to nine rectangular image data overlapping the view are selected from the optimum layer.

  In the accumulation memory configured as described above, in the present invention, a mechanism for reusing (recycling) the contents stored in the accumulation memory as much as possible is provided. 24 and 25 are diagrams showing a memory usage flow in the system of the image display processing device according to the embodiment of the present invention.

  In FIG. 24, when the accumulation memory utilization flow is started in step S200, it is determined whether an event (enlargement request, reduction request, movement request, etc.) has occurred in the view (virtual plane rectangle) of the image display processing device system. Is done. If the determination result is No, step S201 is looped. When the determination in step S201 is Yes, the process proceeds to step S202, and the layer most suitable for display on the view is searched by the above-described search method using scoring. Next, the process proceeds to step S203, and the rectangular image data used for the searched layer is examined to be listed.

  Next, the process proceeds to step S204, where it is determined whether the listed rectangular image data already exists in the accumulation memory. If the determination result is Yes, the process proceeds to step S205, the usage counter is incremented by 1, and display on the view is performed in step S206.

  When the determination result in step S204 is No, the process proceeds to step S207, where it is determined whether or not all the listed rectangular image data to be displayed in the view are prepared. Here, when the range result of step S207 is Yes, it progresses to step S211 and a process is complete | finished. When the determination result in step S207 is No, the process proceeds to step S208, and it is determined whether or not there is an empty memory area in the deposition memory. If it is determined that there is a free memory area, the process proceeds to step S209, where the rectangular index data and the rectangular image data (actual data) are stored in the free memory area, and then the process returns to step S207 again to display all rectangular images. It is determined again whether the data is ready. If the determination result is No in step S208, the process proceeds to step S210, and then the process proceeds to the memory metabolism subroutine shown in FIG.

  FIG. 25 shows a memory metabolism subroutine when there is no free memory area. This routine will be described below. When the memory metabolism subroutine is started in step S300, it is determined in step S301 whether or not there is no rectangular image data stored / stored in the memory area outside the view. Here, the outside of the view is a state in which there is no portion that overlaps the rectangular image data and the rectangle of the view, and they are completely separated. For example, if the image data being handled is a map or an aerial photograph, it may be handled in the same manner as “empty” if the rectangular image data is outside the view in the hierarchical structure. In this way, the importance of information outside the view is low because the “overlapping area ratio” between the rectangular image data and the view is an important factor in the search method based on scoring. This is because there is almost no possibility that the rectangular image data affects the selection of the optimum layer. Therefore, as the order of metabolism (memory area release), the outside of the view is given priority over the situation of the optimum layer.

  If the determination result in step S301 is Yes, the memory area in which the data is stored is metabolized (memory area release) in step S303, and a new rectangular index is created in the place where the free memory area is obtained in step S304. Data and rectangular image data (actual data) are stored, new rectangular index data is displayed on the view in step S305, and a return is returned in step S309.

  If the determination result in step S301 is No, it is determined in step S302 whether rectangular image data having different layers exists in the deposition memory. If the determination is Yes, the memory area in which the data is stored is metabolized (memory area is released) in step S303, and new rectangular index data and a rectangle are created in the place where the free memory area is obtained in step S304. Image data (actual data) is stored, new rectangular index data is displayed in the view in step S305, and a return is returned in step S309.

  A description will be given of the determination in step S302 as to whether or not the rectangular index data belongs to a layer different from the optimum layer. When an event occurs in the view, the optimal layer is always selected, so the memory area that stores the rectangular index data that belongs to a layer different from the optimal layer is one of the goals to be metabolized. Priority is given to the outside of the aforementioned view (step S301). The reason is that it is desirable to leave as much rectangular image data as possible on the view regardless of whether it is the optimum layer or not. There is a high possibility that rectangular image data that overlaps the view even if it belongs to a layer different from the optimal layer will be filled in when there is a blank in the optimal layer. This is because when the image data is a map or an aerial photograph, the higher the layer, the rectangular image data covers a wider range and always overlaps the view. Further, even when the optimum layer is changed, if the remaining rectangular image data layer matches the optimum layer, it is likely that the layer can be used as it is because it originally overlaps the view. However, the degree of these possibilities depends on the number of memory areas that can be secured in the accumulation memory and the structure of the hierarchical structure (rectangular arrangement format, number of layers, information density of layers).

  If the determination result in step S302 is No, the process proceeds to step S306, and the memory area usage count counter is referred to, the rectangular image data with a lower usage count is discarded, and the memory area is metabolized. . The usage number counter counts the number of times the rectangular image data is reused. The number of times of reuse is the number of times that the memory area is displayed without being replaced.

  Next, in step S307, the new rectangular index data and the rectangular image data (actual data) are stored in the place where the free memory area is reached, the new rectangular index data is displayed in the view in step S308, and the return is returned in step S309. Become.

  As described above, according to the image display processing apparatus of the present invention, due to the simplicity and independence of the basic components (rectangular image data, rectangular index data), the entity of the information structure can be mass-produced at low cost, and various types of information can be produced. Can respond flexibly. Further, according to the image display processing device of the present invention, appropriate information (rectangular image data of an appropriate layer) corresponding to the position and range of interest is selected and displayed from a large amount of position and shape information. Therefore, the user is always provided with sufficient information as necessary. Since the switching control mechanism (scoring method by score) selects and displays appropriate information according to the position and range of interest, information can be provided to the user without stress. In scoring, the use of a non-linear evaluation formula increases the possibility that a higher layer will be displayed, and the effect of making it difficult to display a blank on the screen is obtained. Further, according to the image display processing apparatus of the present invention, a smooth display corresponding to an enlargement / reduction / movement operation can be performed even in an information processing apparatus having relatively low performance such as a small portable information terminal device such as a PDA or a notebook PC. Is possible. In addition, according to the image display processing apparatus of the present invention, the information structure and its processing mechanism take into account margins at key points in order to allow ambiguity, and as a result, include other programs, apparatuses, and methods. Can be realized.

1 is a schematic configuration diagram of an entire system of an image display processing device according to an embodiment of the present invention. It is a figure which shows the concept of the rectangle index data in the image display processing apparatus which concerns on embodiment of this invention. It is a figure which shows the example of an arrangement | sequence of the rectangular image data in the image display processing apparatus which concerns on embodiment of this invention. It is a figure which shows the image of the view of the hierarchical structure of the image display processing apparatus which concerns on embodiment of this invention. It is a figure which shows the hierarchical structure by the rectangular image data of the image display processing apparatus which concerns on embodiment of this invention. It is a figure which shows the hierarchical structure by the rectangular image data of the image display processing apparatus which concerns on embodiment of this invention. It is a figure which shows the hierarchical structure by the rectangular image data of the image display processing apparatus which concerns on embodiment of this invention. It is the figure which imaged the idea of the optimal layer selection in the image display processing apparatus which concerns on embodiment of this invention. It is the figure which imaged the relationship between the virtual plane area | region and rectangular index data in the predetermined level layer in the image display processing apparatus which concerns on embodiment of this invention. It is a figure for demonstrating calculation of the overlapping area ratio in the scoring in the image display processing apparatus which concerns on embodiment of this invention. It is a figure which shows the calculation flow of the overlap information density ratio in scoring in the image display processing apparatus which concerns on embodiment of this invention. It is a figure explaining the example of calculation of the information density ratio in the image display processing apparatus of this invention. It is a figure explaining the specific gravity of the layer in scoring in the image display processing apparatus which concerns on embodiment of this invention. It is a figure explaining the example of calculation of the score in the image display processing apparatus which concerns on embodiment of this invention. It is a figure which shows the precondition for demonstrating the effect of "the specific gravity of a layer". It is a figure for demonstrating the effect of "the specific gravity of a layer." It is a figure for demonstrating the effect of "the specific gravity of a layer." It is a figure for demonstrating the effect of "the specific gravity of a layer." It is a figure for demonstrating the effect of "the specific gravity of a layer." It is a figure for demonstrating the effect of "the specific gravity of a layer." It is a figure for demonstrating the effect of "the specific gravity of a layer." It is a figure which shows the image of utilization of the memory in the system of the image display processing apparatus which concerns on embodiment of this invention. It is a figure which shows the image of utilization of the memory area in the system of the image display processing apparatus which concerns on embodiment of this invention. It is a figure which shows the utilization flow of the memory in the system of the image display processing apparatus which concerns on embodiment of this invention. It is a figure which shows the utilization flow of the memory in the system of the image display processing apparatus which concerns on embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... System bus, 11 ... CPU (Central Processing Unit), 12 ... RAM (Random Access Memory), 13 ... ROM (Read Only Memory), 14 ... Communication control part, 15. ..Input control unit, 16 ... output control unit, 17 ... external storage device control unit, 18 ... input unit, 19 ... output unit, 20 ... external storage device

Claims (10)

A device that operates with a system program including a CPU , manages geospatial information of the same object in a plurality of hierarchical structures, and displays a part of the geospatial information selected by the user on a display screen In the image display processing device,
The hierarchical structure is composed of layers with different information densities, the layer is composed of rectangular image data obtained by dividing geospatial information into a plurality of rectangles, and rectangular index data for holding the index data of the rectangular image data is prepared. When a part of the geospatial information selected by the user is displayed on the display screen, the overlap area ratio indicating the degree of overlap between the display area of the display screen and the rectangular image data and the rectangle of the display area are displayed. An information density ratio obtained by dividing a quotient obtained by dividing an average of information density of overlapping rectangular image data by a layer by an information density of a display area to a ratio by a predetermined threshold, and a base number is raised to a power according to the information density of the layer An image display processing apparatus, wherein a score of each layer is calculated based on the specific gravity of the layer and a rectangular image data of a plurality of layers is to be displayed. The image display processing apparatus according to claim 1, wherein the rectangular shape of the rectangular image data is arbitrary. The score is
(Score) = (Overlapping area ratio) x (Information density ratio) ÷ (Layer specific gravity)
The image display processing device according to claim 1 , wherein the image display processing device is calculated according to claim 1 . 4. The image display according to claim 1, wherein a memory having a plurality of basic areas for storing pairs of rectangular index data and rectangular image data is used for display on the display screen. Processing equipment. 5. The image display processing apparatus according to claim 4 , wherein the basic area is provided with a counter that counts how many times the stored pair of rectangular index data and rectangular image data is used. 6. The image display processing apparatus according to claim 4 , wherein when displaying on the display screen, only a basic area that needs to be rewritten is rewritten among a plurality of basic areas of the memory. The rewrite order when rewriting the basic area of the memory is as follows: the basic area that holds the rectangular image data outside the display screen, the basic area that holds the rectangular image data of a layer different from the layer to be displayed, and the number of counts by the counter The image display processing apparatus according to claim 6 , wherein the image display processing apparatus is in the order of basic areas holding rectangular image data with a small amount of image data. The image display processing device according to claim 1 , wherein the geospatial information is mesh data. The image display processing device according to claim 1 , wherein the geospatial information is vector data. The image display processing device according to claim 1 , wherein the geospatial information is mesh data and vector data.

Images