Presentation apparatus for two-dimensional picture information

A picture to be printed is prepared by DTP software and is stored into layer L0 of the file F which is distributed to respective correctors. The first corrector writes correcting indication K1 onto layer L1, the second corrector writes correcting indication K2 onto the layer L2 and the third corrector writes correcting indication K3 onto the layer L3. For the respective layers, respective passwords are to be set for ensuring securities. In order to display or to edit a specific layer, it is required to input a proper password. Layer information ranging over plural files can be united within a single file and are handled with a unified manner.

BACKGROUND OF THE INVENTION 
This invention relates to a presentation apparatus for two-dimensional 
picture information and, more particularly, to an apparatus for presenting 
information which is distributed and preserved into plural layers located 
on the same area with overlapping manner. 
At present, many kinds of information can be displayed on a display screen 
of the computer. It is expected that this tendency is further spurred in 
future by popularization of the internet. In recent years, with 
improvement of resolution of display, it becomes possible to present 
considerably fine information. In the car navigation system, etc., a 
device for presenting a detailed map on a two-dimensional display screen 
is assembled. 
Moreover, by popularization of the so-called DTP (Desk Top Publishing) 
technology, it has been popularized to carry out editing work by using 
computer in the field of printing. In the DTP, layout work for characters 
or photographs to be printed is carried out on the display screen of the 
computer, and all sorts of information necessary for printing are 
displayed on the display screen. Further, in recent years, a document 
format PDF (Portable Document Format) that Adobe Systems Co. Ltd. in the 
U.S. has announced has been popularized. A picture image to be printed can 
be stored in a PDF file. When this PDF file is delivered to proofreaders, 
they can proceed with their correcting work on the display screen. 
In the case where very complicated information such as information on a map 
or various correcting instructions in the DTP, etc. are presented onto a 
two-dimensional screen, information to be displayed is usually distributed 
and preserved into plural layers. For example, in the case of information 
of a map, when a layer including fundamental geographic data such as road 
or topography, etc. and a layer including particular location data such as 
particular places of restaurant or home, etc. are separately handled, it 
is possible to display only a necessary layer as occasion demands. 
Moreover, in the case of carrying out editing work such as changing the 
place of home, etc., only a layer to be edited can be selected. 
Accordingly, such an error that fundamental geographic data of the map is 
erroneously altered can be prevented. Multiple layers are also convenient 
in DTP work. When a layer indicating a picture to be printed and a layer 
indicating editorial instructions are separately managed, the editorial 
instructions can be clearly distinguished. 
As described above, an approach to handle the information in the state 
delivered into plural layers has a great merit in improving display or 
editing efficiency in presenting a large number of information onto the 
two-dimensional screen. However, in the conventional typical presenting 
device for two-dimensional information, there is a problem that it is 
difficult to utilize the system with enough security. For example, let 
consider the case where editorial corrections with respect to the DTP work 
are carried out on the display screen. In typical commercial printed 
matters, not only an editor but also plural persons including a designer, 
a copy writer or a sponsor, etc. participate in the correcting work. 
Hitherto, such plural persons carry out work for respectively writing 
instructions for correction onto the picture to be printed. In this case, 
it is impossible to rigorously recognize the actual relationship between 
respective persons and respective instructions. For this reason, there was 
a problem that sufficient security relating to correcting responsibility 
could not be maintained. If the correction work is carried out on a paper, 
it is possible to clarify the correcting responsibility by signature of 
respective correctors. However, when the correction work is carried out on 
the screen, it is very hard to clarify the correcting responsibility, 
since signatures are not available on the screen. This was a big problem 
in business. 
Another problem in the conventional device for presenting two-dimensional 
picture information is that layer information belonging to different files 
cannot be unified. In general, picture information produced by computer is 
handled as a file unit. Accordingly, in the case of DTP work on the 
display screen, if there is employed an approach to send a file in a 
sequential order to, for example, a designer, a copy writer and a sponsor 
and to make them write instructions for correction on the same file, such 
file can be dealt as an only file at all times. However, in many practical 
instances, another approach is usually employed to duplicate a file, to 
separately send the duplicated files to a designer, a copy writer and a 
sponsor and to make them write instructions for correction on the 
respective individual files by parallel processing. In this case, plural 
corrected files are finally returned to the editor. Thus, the editor owes 
the additional work for taking out and gathering necessary correcting 
information from the respective files. 
This invention has been made in order to solve the above-described problem 
that the conventional device for presenting two-dimensional picture 
information has. The object of the present invention is to provide a 
presentation apparatus for two-dimensional picture information which can 
maintain security for respective layers and handle layers between plural 
files in unified manner. 
SUMMARY OF THE INVENTION 
(1) The first feature of the invention resides in a presentation apparatus 
for two-dimensional picture information, comprising: 
display means for displaying a predetermined picture in a two-dimensional 
display area; 
memory means for preserving contents to be displayed in the display area as 
data in a state divided into plural layers; and 
display control means for reading out data with respect to a designated 
layer from the memory means in accordance with a layer designation 
inputted by an operator, preparing a picture to be displayed on the basis 
of the data which has been read out and delivering the prepared picture to 
the display means to display it; 
wherein the display control means has a function to set a password with 
respect to a specific layer based on demand of the operator and, when a 
layer in which the password is set is designated, to display contents of 
the designated layer in the display area provided that the password is 
inputted. 
(2) The second feature of the invention resides in a presentation apparatus 
for two-dimensional picture information, comprising: 
display means for displaying a predetermined picture in a two-dimensional 
display area; 
memory means for preserving contents to be displayed in the display area as 
data in a state divided into plural layers; 
display control means for reading out data with respect to a designated 
layer from the memory means in accordance with a layer designation 
inputted by an operator, preparing a picture to be displayed on the basis 
of the data which has been read out and delivering the prepared picture to 
the display means to display it; and 
editing means for editing data with respect to a designated layer in 
accordance with a layer designation and an editing instruction inputted by 
the operator and storing edited data into the memory means; 
wherein the editing means has a function to set a password with respect to 
a specific layer based on demand of the operator and, when a layer in 
which the password is set is designated, to edit contents of the 
designated layer provided that the password is inputted. 
(3) The third feature of the invention resides in a presentation apparatus 
for two-dimensional picture information, comprising: 
display means for displaying a predetermined picture in a two-dimensional 
display area; 
memory means for preserving contents to be displayed in the display area as 
data in a state divided into plural layers; 
display control means for reading out data with respect to a designated 
layer from the memory means in accordance with a layer designation 
inputted by an operator, preparing a picture to be displayed on the basis 
of the data which has been read out and delivering the prepared picture to 
the display means to display it; and 
editing means for editing data with respect to a designated layer in 
accordance with a layer designation and an editing instruction inputted by 
the operator and storing edited data into the memory means; 
wherein the display control means has a function to set a display password 
with respect to a specific layer based on demand of the operator and, when 
a layer in which the display password is set is designated, to display 
contents of the designated layer in the display area provided that the 
display password is inputted; and 
wherein the editing means has a function to set an editing password with 
respect to a specific layer based on demand of the operator and, when a 
layer in which the editing password is set is designated, to edit contents 
of the designated layer provided that the editing password is inputted. 
(4) The fourth feature of the invention resides in a presentation apparatus 
for two-dimensional picture information in accordance with the first or 
the third feature: 
wherein data of a specific layer is preserved within the memory means in an 
enciphered state, whereby in the case where collation of the password is 
succeeded, the data is decoded so that contents of the specific layer are 
displayed in a state where they can be recognized, while in the case where 
collation of the password is failed, the data is not decoded so that 
contents of the specific layer are displayed in a state where they cannot 
be recognized. 
(5) The fifth feature of the invention resides in a presentation apparatus 
for two-dimensional picture information in accordance with the first to 
the fourth features, further comprising: 
file synthesis means having a function to combine a first file and a second 
file into a third file; 
wherein the first file consists of a first group of data having at least 
one layer and a second group of data having at least one layer, and the 
second file consists of a third group of data having at least one layer 
and a fourth group of data having at least one layer, the first group of 
data and the third group of data being same; and 
wherein the file synthesis means produces the third file by gathering the 
first, second and fourth group of data. 
(6) The sixth feature of the invention resides in a computer readable 
recording medium on which there is recorded a program for allowing a 
computer to function as the memory means and the display control means 
mentioned in the first to the fifth features. 
(7) The seventh feature of the invention resides in a computer readable 
recording medium on which there is recorded a program for allowing a 
computer to function as the memory means, the display control means and 
the editing means mentioned in the first to the fifth features.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
This invention will now be described in accordance with the embodiment 
shown below. 
.sctn.1 Apparatus for Presenting Information Relating to Map 
The preferred embodiment to which the present invention is applied to an 
apparatus for presenting map onto two-dimensional display will be first 
described. FIG. 1 is a block diagram showing a fundamental configuration 
of the apparatus according to this embodiment. As shown, this apparatus is 
composed of display means 10, memory means 20 and display control means 
30. The display means 10 has a function to display a predetermined picture 
in a two-dimensional display area 11, and can be constituted by widely 
used display device for computer in more practical sense. The memory means 
20 has a function to preserve contents to be displayed on the display area 
11 in the state divided into plural layers which have a common 
two-dimensional coordinate. The memory means 20 can be constituted by a 
memory device or an external memory unit for computer in more practical 
sense. In this example, there is shown the state where information 
relating to map is preserved into three layers A, B and C. In addition, 
the display control means 30 has a function to read out data of a 
designated layer or designated layers from the memory means 20 in 
accordance with a layer designation command given from the external. The 
display control means 30 also has a function to prepare a picture to be 
displayed on the basis of the data which has been read out and to present 
the prepared picture on the display area 11 of the display means 10. In 
practical, the display control means 30 can be realized by program 
installed into the computer. 
In the example shown, fundamental information of map is included in the 
layer A preserved within the memory means 20. Information of restaurant 
within this map is included in the layer B, and information of the parking 
area within the map is included in the layer C. Information of these three 
layers A, B and C are synthesized and displayed on the display area 11 of 
the display means 10. When a user gives a layer designation command which 
instructs to display all the three layers A, B and C, to the display 
control means 30, the display control means 30 reads out all the data 
included in the three layers A, B and C from the memory means 20 and 
synthesizes those data (superimpose them on a common two-dimensional 
coordinate plane) so that a display as shown in FIG. 1 is obtained in the 
display area 11. 
The characterized feature of this apparatus is that a password can be set 
with respect to a specific layer as occasion demands. In the example 
shown, a password is not set by any means to the layer A, a password of 
"BB123" is set for the layer B, and a password of "CC123" is set for the 
layer C. While these passwords are preserved within the memory means 20 
along with data of the respective layers, it is preferable that they are 
preserved in such a way that they cannot be recognized by ordinary 
read-out method. In the case where a layer in which a password is set is 
designated, the display control means 30 displays the contents of this 
designated layer on the display area 11, provided that the proper password 
has been inputted. For example, when a user gives a layer designation 
command to display all of the three layers A, B and C, the display control 
means 30 makes a request for a password for displaying the layer B and a 
password for displaying the layer C. If the user inputs correct passwords, 
i.e., "BB123" and "CC123" with respect to this request, a display as shown 
in FIG. 1 is obtained in the display area 11. However, if a correct 
password has not been inputted with respect to a particular layer, the 
contents of this particular layer are not displayed. 
In such a system to make a request for a password for the purpose of 
displaying a specific layer, it is possible to maintain security. Let 
consider the case where a CD-ROM in a form of memory means 20 as shown in 
FIG. 1 is put on sale as software map. Assuming that an initial price of 
this CD-ROM is set to an utilization cost of the layer A (utilization cost 
of only fundamental map information). In this case, a user who has 
purchased this CD-ROM can display the contents of the layer A on the 
display area 11 by using the display control means 30 (a computer provided 
with a CD-ROM drive unit in this case). However, since the user does not 
know a password with respect to the layer B or C, the contents of these 
layers cannot be displayed. In view of the above, when the user intends to 
display restaurant information on the map, it is sufficient to pay 
utilization cost of the layer B (utilization cost of restaurant 
information) to thereby obtain the password "BB123". By inputting this 
password with respect to the display control means 30, restaurant 
information can be obtained on the display area 11. Moreover, in the case 
where the user intends to further display information of the parking area 
on the map, utilization cost of the layer C (utilization cost of parking 
area information) may be paid to thereby obtain the password "CC123". Of 
course, payment of the cost may be done through an on-line system and a 
password can be delivered through the on-line system. In addition, 
information of further layers (e.g., information indicating location of 
play facilities) may be obtained through the internet. 
Though a password is used for displaying a specific layer in the 
above-mentioned example, a password can be used for allowing edit in a 
specific layer. In the apparatus shown in FIG. 2, editing means 40 is 
further added to the apparatus shown in FIG. 1. The editing means 40 has a 
function to read out data with respect to the designated layer from the 
memory means 20 in accordance with a layer designation command inputted 
from the external, to edit the read out data in accordance with an editing 
instruction inputted from the external, and to write back the edited data 
into the memory means 20. In the example shown in FIG. 2, fundamental map 
information is included in the layer A preserved within the memory means 
20, individual information of the user B (location of home of the user B 
in the example shown) is included in the layer B, and individual 
information of the user C (location of shop and home of the user C in the 
example shown) is included in the layer C. Data of the layer B or C is 
data that the respective users themselves have written by giving a 
predetermined layer designation command and an editing instruction to the 
editing means 40. 
In the case of the apparatus of FIG. 2, a password is not required by any 
means when individual layers are displayed. However, in the case when 
editing with respect to a particular layer is carried out, a predetermined 
password is required. For the layer A, a password is not set, but editing 
is inhibited by any means with respect to the contents of this layer A 
(such an approach may be employed by setting any password for the layer A 
and inhibiting every user to know this password). On the other hand, the 
password of "BB456" is set for the layer B and the password of "CC456" is 
set for the layer C. These passwords are set for allowing users B and C to 
provide access to their own layers. When a layer for which a password has 
been set is designated to be edited, the editing means 40 executes editing 
with respect to the contents of this designated layer, provided that the 
proper password is inputted. Accordingly, if the user B tries to register 
location of his home, it is necessary to designate the layer B to carry 
out this registration work by inputting the password "BB456" into the 
editing means 40. Similarly, in the case where the user C tries to 
register location of his shop or his home, it is necessary to designate 
the layer C to carry out this registration work by inputting the password 
"CC456" into the editing means 40. 
In accordance with such a system to require a password for editing a 
specific layer, the security relating to editing can be taken into 
consideration. Namely, even in the case where plural users utilize the 
same system as shown in FIG. 2, as a layer including individual 
information of a specific user can be edited only by this user, there is 
no possibility that the individual information is altered by the other 
user. 
Of course, in the apparatus shown in FIG. 2, a password for displaying a 
specific layer can be also set. An example where a display password for 
displaying a specific layer and an editing password for editing a specific 
layer are set in this way is shown in the block diagram of FIG. 3. Though 
the contents themselves of layers A, B and C preserved in the memory means 
20 are the same as that shown in FIG. 2, both the editing password "BB456" 
and the display password "BB789" are set with respect to the layer B, and 
both the editing password "CC456" and the display password "CC789" are set 
with respect to the layer C. Accordingly, when the user tries to edit the 
layer B or C, it is necessary to input the editing password "BB456" or 
"CC456" to the editing means 40 and when the user tries to display the 
contents of the layer B or C, it is necessary to input the display 
password "BB789" or "CC789" to the display control means 30. 
As described above, when both the display password and the editing password 
are set with respect to a specific layer, only the user is permitted to 
display or to edit the contents of this specific layer which includes 
his/her individual information. Thus, higher level security can be 
ensured. 
The presentation apparatus shown in FIG. 4 is an apparatus in which file 
synthesis means 50 is further added to the apparatus shown in FIG. 2 or 3. 
The file synthesis means 50 has a function to synthesize plural files 
preserved within the memory means 20. The function of the file synthesis 
means 50 will now be described in a practical example in which a first 
file F1 and a second file F2 within the memory means 20 are synthesized. 
Let now consider that the two files F1, F2 preserved within the memory 
means 20 have layer configuration as shown in FIG. 5. The first file F1 is 
a file composed of three layers A, B and C preserved within the memory 
means 20 of FIG. 1 and the second file F2 is a file composed of also three 
layers A, B and C preserved within the memory means 20 of FIG. 2. All 
these files consist of information relating to the map, wherein the first 
file F1 is a file including location information of restaurants and 
parking areas and the second file F2 is a file including individual 
information of the users B and C. In general, picture information 
processed by computer is handled as a file, and the display control means 
30 and the editing means 40 have a function to display or edit the 
contents of the file. Accordingly, as shown in FIG. 5, information in the 
first file F1 and information in the second file F2 within the memory 
means 20 are handled as individual information and they could not be 
handled in unified manner. The file synthesis means 50 has a function to 
synthesize such two files F1 and F2 to merge them into a new file F3. The 
fundamental principle of the file synthesis operation that the file 
synthesis means 50 carries out is as follows. 
Initially, layers having the common contents are recognized among these 
layers constituting the two files F1 and F2 In case of the example shown 
in FIG. 5, the layer A within the first file F1 and the layer A within the 
second file F2 are layers having the common contents of fundamental map 
information (hereinafter these layers are referred to as a common layer). 
On the contrary, the layers B and C within the first file F1 and the 
layers B and C within the second file F2 are layers having individual 
information (hereinafter these layers are referred to as an individual 
layer). Now, for convenience of explanation, the classification is assumed 
to be made such that the common layer A of the first file F1 belongs to 
the first group G1, the individual layers B and C of the first file F1 
belong to the second group G2, the common layer A of the second file F2 
belongs to the third group G3 and the individual layers B and C of the 
second file F2 belong to the fourth group G4. After such a classification 
is made, the layers belonging to the first group G1, the layers belonging 
to the second group G2 and the layers belonging to the fourth group G4 are 
gathered to constitute the third file F3. This third file F3 is a file 
obtained by synthesizing the first file F1 and the second file F2. 
FIG. 6 is a block diagram showing the layer configuration of the third file 
F3 thus obtained. It is seen that only a layer belonging to the third 
group G3 shown in FIG. 5 is deleted. Since the layers B and C belonging to 
the second group G2 and the layers B and C belonging to the fourth group 
G4 have the same names in the example shown in FIG. 5, the names of the 
layers belonging to the fourth group G4 are changed to D and E in the 
third file F3 shown in FIG. 6. It is to be noted that passwords set for 
the respective layers before this synthesis operation are caused to be 
maintained as they are. 
When the two files F1 and F2 are merged into the third file F3 as mentioned 
above, the display control means 30 and the editing means 40 can handle 
the five layers A to E included in the third file F3 in unified manner. 
For example, all the five layers A to E can be displayed in the display 
area 11 in the state where they overlap with each other, provided that the 
proper passwords are inputted. In addition, since only one of the common 
layers is left and the other layer or layers are deleted, irrationality 
such that the same layers are caused to overlap with each other within the 
same file can be avoided. Of course, the third file F3 prepared by this 
synthesis operation is further synthesized with another fourth file F4, 
thereby making it possible to prepare a fifth file F5. 
.sctn.2 Apparatus for Presenting Correction Information in DTP 
Subsequently, another embodiment will now be described, in which the 
present invention is applied to the apparatus for presenting correction 
information onto the two-dimensional display in DTP. Since the block 
configuration of this apparatus is the same as the apparatus for 
presenting map information described in .sctn.1 (e.g., the apparatus shown 
in FIG. 3), only the contents displayed on the display area 11 and the 
layer configuration within the memory means 20 will be explained. 
FIG. 7 is a block diagram showing one example of flow of work in the case 
where an advertiser publishes advertisement of mail order on magazine, 
etc. First of all, the advertiser makes an order of advertisement to an 
advertisement agency. The advertisement agency gives an instruction to a 
publishing company so as to prepare contents of advertisement in comply 
with the need of the advertiser. At the publishing company, an editor in 
charge prepares advertisement pages in accordance with the advertiser's 
demand with being helped by an external designer or a copy writer. 
Ordinarily, at the publishing company, the editor in charge proceeds with 
work by using dedicated software, and work result (picture to be printed) 
is stored in a form of a digital file with format of this software. When 
this file is sent to the printing company, actual printing process is 
carried out. Usually, a correcting procedure is carried out before the 
actual printing process. Although the correcting procedure can be carried 
out by using DTP dedicated software, in recent years a general-purpose 
document processing software is widely used for this correcting procedure. 
In this case, picture data to be printed is converted into a file of 
general-purpose format and the correcting procedure is carried out for 
this converted file using the general-purpose document processing 
software. In this embodiment, a file prepared by the DTP dedicated 
software at the publishing company is converted into a PDF file (Portable 
Document Format: a general-purpose format which the U.S. Adobe systems 
Inc. has announced) and the correcting procedure is carried out by 
inputting correcting instructions to this PDF file. 
For convenience of explanation, a picture to be printed as shown in FIG. 8A 
is assumed to be prepared at the publishing company. Various picture 
information such as photo pictures, illustration pictures and image of 
character strings, etc. are included in a picture to be printed. At the 
publishing company, the picture to be printed is converted into a PDF file 
and this PDF file is distributed to respective correctors. While the PDF 
file may be distributed through a physical medium such as floppy disc, 
etc., it is common at present to distribute it on the on-line basis by 
using communication line. The correcting work is ordinarily carried out 
not only by an editor in charge in the publishing company but also by a 
designer, a copy writer, an advertiser and an advertisement agency who 
participate in this publishing work. In this example, let consider the 
case where the correcting work is carried out by three persons of an 
editor, a designer and a copy writer with respect to a picture to be 
printed shown in FIG. 8A for convenience of explanation. 
The correcting work on the display screen is usually similar to the work on 
the actual paper. That is, figures, symbols or comments are written onto a 
picture on the screen with relatively conspicuous color. It is now assumed 
that, with respect to the picture to be printed shown in FIG. 8A, a 
correcting indication K1 as shown in FIG. 8B is written by the editor, a 
correcting indication K2 as shown in FIG. 8C is subsequently written by 
the designer and a correcting indication K3 as shown in FIG. 8D is finally 
written by the copy writer. The respective correcting indications K1, K2 
and K3 are messages for instructing change of font or size, or color 
modification with respect to a portion of a specific character or a 
picture. At the next stage in the publishing company, necessary 
modification is made to the picture to be printed on the basis of these 
messages thereafter to make an order of printing to the printing company. 
When the apparatus according to this invention is used, it is possible to 
preserve these correcting indications on individual layers for respective 
correctors. The file F shown in FIG. 9 consists of four layers L0 to L3. 
In this example, the layer L0 includes a picture itself to be printed and 
this picture is a subject for correction work. On the other hand, the 
layers L1, L2 and L3 are layers for preserving correcting indications of 
the editor, the designer and the copy writer, respectively. 
When the apparatus according to this invention shown in FIG. 3 is used, it 
is possible to set an editing password and a display password as occasion 
demands for every respective layer. In the case of the example shown in 
FIG. 9, though a display password is not set for the layer L0 so that 
everybody can freely display the layer L0, an editing password is set for 
the layer L0 by the editor of the publishing company so as to inhibit 
editing by somebody except for the editor. 
With respect to the layers L1 to L3, no display password is set so that 
everybody can freely display the layers L1 to L3. However, respective 
editing passwords are set by the individual correctors to permit editing 
only by the authorized correctors. That is, specific editing passwords are 
set for the layers L1, L2 and L3 by the editor, the designer and the copy 
writer, respectively, so that editing work for the layers L1, L2 and L3 is 
only permitted by the editor, the designer and the copy writer, 
respectively. If there is employed an approach to set such a security that 
respective correctors can edit only his/her own layer, responsibility for 
correcting instructions becomes clear, thus making it possible to prevent 
occurrence of useless trouble. 
It is to be noted that, in the apparatus according to this embodiment, a 
window 100 shown in FIG. 10 is displayed on the display screen so that 
management of correction layers can easily be made. On the layer 
management window 100, layer display columns 110 to 170 are arranged, and 
a NEW button 180 for preparing "new correction layer" is provided. 
Moreover, in the vicinity of the right side, there are scrolling buttons 
191, 192 and a scrolling bar 193 for carrying out scrolling operation of 
the respective layer display columns 110 to 170 in upper and lower 
directions. In the respective layer display columns 110 to 170, check 
boxes 101, radio buttons 102 and title windows 103 are respectively 
provided. 
One layer display column corresponds to one correction layer, and, e.g., 
the layer display columns 110, 120, 130 respectively correspond to the 
layers L1, L2, L3 in the file F in FIG. 9. Layer names attached to the 
corresponding layers (corrector name in the case of this example) are 
displayed on the title windows 103. 
The check box 101 serves to designate whether or not the corresponding 
layer should be displayed. Every time the check box 101 is clicked by a 
pointing device such as mouse, etc., a check mark X is attached or is not 
attached (alternately inverted). On the display screen, only the layers 
having check mark X are displayed. In the example shown, four layers 
corresponding to the layer display columns 110 to 140 are displayed. It is 
to be noted that since a display password is not set by any means in this 
embodiment, inverting operation of the check box 101 can be freely carried 
out without inputting any password. 
On the other hand, the radio button 102 serves to designate whether or not 
editing is carried out with respect to the corresponding layer. Every time 
the radio button 102 is clicked by a pointing device such as mouse, etc., 
a black circle is attached or is not attached (alternately inverted). It 
is to be noted that addition of black circle is exclusive. In other word, 
the black circle can be attached to only one of the layer display columns. 
For example, when the radio button 102 within the layer display column 130 
is clicked in the state as shown in FIG. 10, the black circle of the radio 
button 102 within the layer display column 120 is released. Eventually, 
the editing work is carried out for only a chosen correction layer at all 
times. In addition, when the radio button 102 is newly clicked to chose a 
specific layer so that it is to be edited, a dialog box 200 as shown in 
FIG. 11 is displayed on the screen. This dialog box 200 demands input of 
the editing password with respect to the corresponding layer. FIG. 11 
shows the example where the radio button 102 within the layer display 
column 130 is clicked to chose the correction layer for copy writer to be 
edited. In this case, if the correct password is inputted, choosing 
operation of the radio button 102 is handled as effective. On the 
contrary, in the case where the inputted password is not correct, this 
choosing operation is nullified. 
When the NEW button 180 is clicked in order to add a new correction layer, 
a dialog box 300 as shown in FIG. 12 is displayed. The user may input any 
character strings for NAME OF CORRECTOR (name of layer) and PASS WORD 
(editing password) in the respective columns. For example, if a correction 
layer for the advertiser is newly supplemented, the user inputs 
"advertiser" at the column of NAME OF CORRECTOR and an arbitrary password 
at the column of PASS WORD. Thus, the new name "advertiser" is inserted in 
the blank title window 103 of the layer display column 150 in FIG. 10 and 
a new layer is supplemented. 
While the embodiment in which file synthesis means 50 is further provided 
has been described in .sctn.1 as shown in FIG. 4, this file synthesis 
means 50 is extremely useful also in the above-described apparatus for 
correction work. For example, in the above-described procedure, there has 
been carried out a sequential correction work for the picture shown in 
FIG. 8A. That is, the editor writes the correcting indication K1 at the 
first stage (FIG. 8B), then the designer writes the correcting indication 
K2 at the second stage (FIG. 8C) and finally the copy writer writes the 
correcting indication K3 at the third stage (FIG. 8D). When the sequential 
correction work by the plural correctors is carried out in this way, all 
the correcting indications are preserved in the same file F as shown in 
FIG. 9. 
However, in practice, a parallel correction work is apt to be carried out 
by the plural correctors. Let consider, e.g., the case where the editor 
and the copy writer are carrying out their correction work at an office A, 
but the designer is carrying out his/her correction work at another office 
B. In this case, it is possible to proceed with the correction works in 
parallel at the two offices by the following way. First of all, a 
pre-correction file including only the layer L0 (picture to be printed) is 
duplicated to prepare a first file F1 and a second file F2 (both the files 
consist of only the layer L0). Then the correction work using the first 
file F1 is carried out at the office A and the correction work using the 
second file F2 is carried out at the office B in parallel. Assuming that, 
at the office A, a correction layer L1 for the editor is newly added in 
the first file F1 and the editor writes the correcting indication K1 on 
this layer L1 and, subsequently, a correction layer L3 for the copy writer 
is newly added in this first file F1 and the copy writer writes the 
correcting indication K3 on this layer L3. In the upper part of FIG. 13, 
the layer configuration of the first file F1 after the above-described 
correction work has been done is shown. On the other hand, at the office 
B, a correction layer L2 for the designer is newly added in the second 
file F2 and the designer writes the correcting indication K2 on this layer 
L2. In the lower part of FIG. 13, the layer configuration of the second 
file F2 after the above-described correction work has been done is shown. 
Eventually, at the stage where the above-described correction work is 
completed, two files F1 and F2 as shown in FIG. 13 should be gathered at 
the publishing company. For this purpose, the file synthesis means 50 can 
be utilized. When file synthesis processing by the file synthesis means 50 
is carried out, it is possible to prepare a single file F as shown in FIG. 
9 on the basis of the files F1 and F2. Namely, among the five layers 
constituting the two files F1 and F2 as shown in FIG. 13, common layers L0 
(of the first file F1 and the second file F2) having common contents are 
recognized. Then either one of the common layers is left and the other is 
deleted. Of course, it is preferable that any passwords set at the 
respective layers before the synthesis processing are maintained as they 
are after the synthesis processing. 
FIG. 14 shows a modified example of the layer management window 100 shown 
in FIG. 10. In the example shown in FIG. 14, the layer display column 110 
of the uppermost row indicates a default layer named "common layer", this 
layer name being displayed in advance at the title window 103. This 
"common layer" is a layer commonly utilized by all the correctors and 
there is no security. Therefore, a password is not required by any means 
to display or edit the contents of this layer. It is very convenient to 
write a correction information on this "common layer", as far as the 
information does not require any security. When sufficient security should 
be ensured, individual layers indicated by the layer display columns 120, 
130, 140 . . . (in this example, user names of Mr. Suzuki, Mr. Tanaka, Mr. 
Sato . . . are set as layer names) can be used by inputting proper 
passwords as mentioned in the above-described example. 
Another feature of the example shown in FIG. 14 resides in that the layer 
information button 185 is provided. This layer information button 185 is a 
button for displaying various information in regard to a chosen specific 
layer. When this layer information button 185 is clicked in the state 
where the layer titled Mr. Suzuki is chosen as shown in FIG. 14, a layer 
information window as shown in FIG. 15 is displayed. In the example shown 
in FIG. 15, information of user name, layer No., preparation date, 
modification date and note are displayed in the window with respect to the 
chosen layer of Mr. Suzuki. The user can display this layer information 
window as occasion demands to confirm various information and thereafter 
he/she can close the window by clicking "OK" button at the right lower 
portion. It is to be noted that note can be directly inputted on the layer 
information window. 
.sctn.3 Other Embodiments 
While this invention has been described on the basis of various 
embodiments, this invention is not limited to these embodiments, but can 
be carried out in various modes in addition to the above-described 
embodiments. Particularly, two-dimensional picture information to be 
presented is not limited to information relating to map or information 
relating to correcting indication. This invention can be utilized for 
presenting various information using plural layers. For example, this 
invention can be used for presenting questions on the display screen in 
examination. That is, the contents with respect to the examination are 
preserved on a question layer, an answer sheet layer, and a correct answer 
layer, etc. In this case, a student can display only the question layer 
and the answer sheet layer and he/she can edit only the answer sheet layer 
to write his/her answer, though a teacher can display all the layers 
including the correct answer layer to mark or grade. In addition, this 
invention can be also utilized for the apparatus for presenting design 
drawings or circuit diagrams. 
In order to enhance the security, contents of a specific layer can be 
preserved into the memory means in an enciphered state. In this case, when 
collation of password is succeeded, the enciphered contents are decoded 
and displayed in a recognizable form. However, when collation of password 
is failed, the enciphered contents are not decoded and displayed in an 
unrecognizable form. 
In practical, the presentation apparatus for two-dimensional picture 
information according to this invention is realized by installing a 
particular software program into a general computer. Accordingly, in many 
cases, the above-described apparatus is developed as software program and 
this program is provided in a form of data recording medium. 
As stated above, in accordance with the presentation apparatus for 
two-dimensional picture information according to this invention, since the 
layers are managed by passwords, the respective layers can be handled with 
security. Further, since the function to synthesize the layers is 
provided, plural files can be handled in unified manner.