Note: Descriptions are shown in the official language in which they were submitted.
~ This invention relates to apparatus and method for
the s~orage of graphic and other patterns for display on a
visual display unit.
The new telecommunications service "Screen Text"
("videotext interactivP") allows information stored in a
central control to be called up via a telephone line with
the aid of a television or similar visual display unit
3 (VDU). The items of information are displayed on the screen
of the V.D.U. which acts as an output unit. The display
can comprise alphanumerical characters and/or graphic
patterns.
One screen content is refexred to as one page. It
contains for example 960 character arrays which are arranged
in 24 rows each comprising 40 character arrays. In the
event of the display of alphanumerical characters, one
character is displayed in a character arrayO The character
-~ array consists for example of 8 x 10 or 8 x 12 pixels by
which the individual characters are represented. Coarse
graphic patterns are displayed on the basis that each
character array is split into 2 x 3 graphic elements and
the graphic pattern constructed from the possible combi-
nations of light and dark graphic elements.
A predetermined supply of characters and the
possible combinations of graphic elements are stored in
character generators in the output unit. Employing code
words which represent addresses in the character generator,
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data words which are assigrled to the pixels of the
characters or to the graphic elements,-are read out from
the character generators and fed to an image control unit
which controls the display of the characters and of the
patterns of the screen. Display can take place in eight
colours which are governed by corresponding control signals
although only ~ne colour can normally be used within a
character array. The assignment of the code words to the
characters and to the combinations of graphic elements is
known for example from the magazine "Funkschaul' 1977, Vol.
18, page 78-82.
For the representation of fine graphic patterns
whose resolution is more than ten times that of the coarse
patterns, the output unit can contain a further character
generator which stores the graphic patterns not by means
of the graphic elements but, similarly to the characters, by
means of pixels. Following an appropriate switching signal,
data words assigned to the individual pixels of the
character arrays are read out from this character generator
ZO with the aid of code words and are conducted to the image
control unit. The character generator for the fine patterns
is normally designed as a write-read store in order to be able
able to provide display of different patterns depending
upon the application. In the event of a mixed display of
fine pattexns, characters andJor coarse patterns, firstly
the data words of the fine patterns are input from a central
control into the character generator under the addresses
determined b~v the code words. Then the code words for the
characters and/or graphic elements are transferred and at
those points at which the character arrays are to be
filled with the fine patterns the corresponding code words
for the character generator are transmittedO The supply of
fine patterns in the write-read store is known as DRCS
(dynamically redefinable character set).
From the publication "Datensichtgerate" in NTZ
Report 15, 1973, page 27-31 it is known to provide a data
viewing device not only with a character generator for
the alphanumerical characters but also with a further
character generator for circuit symbols. The circuit symbols
are displayed similarly to the characters by means of pixels
within the character arrays. However this further character
generator is designed as an ROM and its contents cannot be
modified by the user.
However it would be conceivable to design the
further character generator as a write-read store and to
input different circuit symbols depending upon the
particular application~ The circuit symbols could be input
by means of a keyboard. In accordance with the pixels of a
character array such a keyboard would consist for example
of 8 x 10 kevs. It would also be possible to provide 8 or
10 keys and to input the patterns of each character array
respectively row by row or column by column. Since the
characters are displayed in a relatively small form on the
;; screen, it would be favourable to represent the corre-
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sponding character array in enlarged orm on the screen
at the time of input.
Although in this way it would be possible to input
the patterns of individual character arrays~ it would be
relatively complicated to input a pattern which extends
over several character arrays. Such a pattern might consist
for example Qf a trade mark, a large symbol, or a text
(3 in a different script, for example in arabic or cyxillic.
It is an aim of the invention to enable a simple
input of fine graphic patterns not only when one individual
character array is ~ be used but even when the pattern
extends over several character arrays.
According to a first aspect of this invention
there is provided apparatus for storing ~raphic and other
patterns for display on a visual display unit, said
apparatus including means for input of a ~ine graphic
(::? pattern, whose display is to be based on a first gridpattern, as a coarse graphic pattern based on a second grid
pattern coarser than the first and comprising one or more
pattern arrays each including a predetermined number of
graphic elements, means for assigning a code word signal
to the or each pattern array, means or converting the or
each pattern array into a respective corresponding
character array of the first grid pattern in which each
character array comprises a plurality of pixels corresponding
in number and relative position within the array to the
graphic elements of each of the pattern arrays, and means
for storing the character arrays, produced by the
conversion, under addresses determined by said code word
signals.
According to a second aspect of this invention
. 5 there is provided a method of storing graphic and other
patterns for display on a visual display unit, said method
including the steps of providing an input of a fine graphic
pattern, whose display is to be based on a first grid
pattern, as a coarse graphic pattern based on a second grid
pattern coarser than the first and comprising one or more
pattern arrays each including a predetermined number of
graphic elements, assign.ing a code word signal to the or
each pattern array, converting the or each pattern array
into a respective corresponding character array of the
first grid pattern, in which each character array comprises
a plurality of pixels corresponding in number and relative
position within the array to the graphic elements of each
of the pattern arrays, and storing the character arrays,
produced by the conversion, under addresses determined by
said code word signals.
A particularly advantageous input of the patterns
is achieved if the enlarged (coarse) representation of the
fine pattern in the second grid pattern takes place on
an original which is scanned opto-electronically. Here it
is advantageous to scan the original line-wise by means
of a scanning unit. It is also possible to effect the
; opto-electronic scanning using a video camera. Regardless
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of whether the coarse patterns or the enlarged fine
patterns are scanned, it is possible to use the same
scanlling units.
A further possibility consists in effecting the
enlarged display of the fine graphic pattern on a visual
display unit by means of a keyboard. The V.D.U. exped-
iently consists o~ a viewing device provided with a
screen. The keyboard csn also be used to correct or amend
patterns originally represented in a different manner.
The keyboard comprises for example a number n x m keys
each of which are assigned to the pixels of a character
array. The patterns cf the various character arrays are
then input by means of an appropriate switching of the
keyboard to the different character arrays. The keyboard
can also comprise n or m keys in order that the patterns
of each character array ma~- be represented row-wise or
line-wise. Another advantageous possibility consists in
, ~ .
using a key~oard which is provided for the input and
correction of the coarse graphic patterns and wherein
20 keys are assigned to respective graphic elements within
a character array. It is also possibie to provide keys
which determine the colour of each character array. The
input can also be effected with an enlarged representation
of the fine graphic pattern on a printed visual data carrier.
It is f~mdamentally possible to assian respective
colours to the character arrays in the enlarged represent-
ation. A small storage requirement in the character
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generator fox the fine patterns is achieved however if
the character arrays which are combined to form a pattern
array each have the same colour. In this case it is
expedient if the colours of the enlarged representation
of the fine graphic pattern are stored within the data for
the respective pattern arrays.
In the case of a mixed display of fine graphic
patterns and coarse graphic patterns and/or characters it
is advantageous for the fine and coarse patterns to be
separa~ely input and for the corxesponding code words to
be input as addresses in the character arrays on which the
fine graphic patterns are represented. If the input takes
place employing originals which are scanned opto
electronicall~ it is favourable that in the original
lS provided wi~h the coarse graphic pat~ern, in the character
arrays on which the fine graphic patterns a're to be
C- represented the addresses of the corresponding pattern
arrays are represented by a point code. In order to be able
to distinguish the point code from the other graphic
patterns it is advantageous for the point code to be
represented in a colour which is impermissible for the
representation of the characters and/or graphic patterns.
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An embodiment of this invention will now be
described, by way of example, with reference to the
accompanying drawings in which:-
Fig~ 1 is a schematic diagram of a portion of a
coarse graphic pattern produced during operation of apparatusembodying this invention;
Fig. 2 is a schematic diagram of a portion of a
text formed during operation of the apparatus;
(~`3 Fig. 3 is a schematic diagram of a portion of a
fine graphic pattern produced during operation of the
apparatus;
Fig. 4 is a schematic diagram of a portion of an
original in which fine graphic patterns are represented in
enlarged form;
Fig. 5 is a schematic diagram of a portion of an
original which contains a coarse graphic pattern and
addresses, coded by means of a point code, for fine graphic
patterns;
,
Fig. 6 is a schematic diagram of a portion of a
representation of a coarse graphic pattern, a fine graphic
pattern, and alphanumerical characters on the screen of an
output unit; and
FigO 7 is a block circuit diagram of apparatus for
producing graphic and other patterns on a visuai display
unit and embodying this invention.
The coarse graphic pattern illustrated in Fig. 1
is formed by individual light or dark graphic elements GE,
of which 2 x 3 are in each case combined to form a character
array ZF. All possible combinations of the graphic elements
GE within the character array ZF are stored in a character
generator of the output unit such as a television device~
The graphic pattern is constructed by calling up the
corresponding combinations by means of assigned code words
in the character generator and are fed to an image control
unit which displays the pattern on a screen of the television
device. For example the character array ZF1 is assiyned the
code word 0100000 and the character array ZF2 is assigned
the code word 1100000. The pattern is stored in the form of
the code words in a store and can be repeatedly read out
therefromO The store is arranged for example in a central
control and the code words are transferred to a further store
in an output unit, said fuxther store being followed in
operational flow by the character generator. The input of
the pattern into the store can be effected via a viewing
device and a keyboard which contains six keys respectively
(~ assi~ned to the graphic elements GE. Extensive patterns can
be represented by means of the original artwork which is
'_hen scanned opto-electronically line by line by means of a
scanner or superficially by means of a video camexa. It is
also possible to input the patterns by means of a graphic in-
pUt terminal Then the corres~onding code woxds are
produced and stored. All in all 960 character arrays ZF can
be represented on the screen these being arranged in 24
rows each comprising 40 chara~ter arravs.
In addition to the coarse graphic patterns, as
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illustrated in Fiy. 2 it is also possible to represent
texts by means of a further character generator. Each
alphanumerical character of the text is likewise represented
in a character array ZF which is of the same size as the
S character arrays ZF illustrated in Fig. 1. However the
characters are represented not by the graphic elements GE
but by image points or pixels BP which are considerably
? smaller than the graphic elements GE. For example 8 x 10
pixels BP are arranged in each character array ZF. The
character itself has a size for example of 5 x 7 pixels BP.
These characters are likewise called up by corresponding
code words in the character generator. For example the
character "V" is called up by the code word 1010110 and the
character "I" is called up by the code word 1001001 in the
character generator.
The character generators for the coarse patterns
and the characters are normally designed as ROMs. In
~3 addition to these two character generators a further
character generator designed as a write-read store can be
provided by means of which fine graphic patterns may be
represented by pixels similarly to the characters.
Fig. 3 illustrates a portion of a fine graphic
pattern which is represented by the pixels BP over a
plurality of character arrays ZF. These character arrays
ZF are the same size as the character arrays ZF in Figs.l
and 2. In the same way as in the representation of the
characters, these charac-ter arrays ZF are likewise formed
131~
from 80 pixels BP which are arranged in n = 8 columns and
m = 10 rows. The individual character arrays ZF are likewise
addressed by code words in the character generatox.
The fine patterns are input into the store of the
central control or into the corresponding dharacter generator
in that firstly, as illustrated in Fig. 1, the pattern is
represented in enlarged form by the graphic elements GE
with the input aid of the keyboard, the original artwork or
(~ by means of a printed representation. The representation
is likewise provided for example by an original which is
then scanned opto-electronically~ In order to represent the
patterns in the individual character arrays in Fig. 3, in
accordance with the n x m pixels BP, n x _ graphic elements
GE are combined to form a pattern axray MF. Then, employing
a control unit, each graphic element GE is assigned one
pixel BP so that each pattern array MF in Fig. 1 is trans-
formed into a character array ZF corresponding to Fig. 3.
(~ For example the pattern array MF in Fig. 1 is transferred
into the character array ZF3 in Fig. 3.
A ~otal of 48 pattern arrays MF can be provided
on the original, each of which arrays is assigned a code
word by way of address. If the pattern array MF in Fig. 1
has the address 1, this corresponds to the code word
0110001. The address 1 can also be represented by a point
code which is formed from the graphic elements GE of a
character array ZFPo If eight different colours can be used
in the representation, the point code, as explained in
detail in the following, is represented in another colour
which is impermissible for the representation.
In the case of the representation illustrated in
~ig. 4~ a plurality of patterns are entered in 32 pattern
arrays MF in one original. The pattern arrays 1 to 7
contain cyrillic letters, whereas the pattern arrays o to
t contain a coherent arabic text, and the pattern arrays 8,
9 to f, ~ to n and v xepresent a coherent graphic pattern.
~ The addxesses of the corresponding pattern arrays MF are
represented on the right hand side by a point code in
character arrays ZFP.
As in the case of the representation of the coarse
patterns, the original is scanned at the time of input and
the input dat~ is stored in a store in which for example
each dark graphic element GE is assigned a binary value 1.
Employing a control unit, the graphic elements GE are
converted into pixels BP and stored in a store. From this
C3 store the pixels are input into the central control store
and if required into the corresponding character generator
of the output unit.
In the case of the representation shown in Fig. 5
it has been assumed that both coarse patterns and also a
part of the fine patterns illustrated in Fig. 4 and a text
are to be represented on the output unit (e.g. tele~ision
set). Following the scanning of the original corresponding
to Fig. 4, the original illustrated in Fig. 5 is scanned
for the coarse pattern Gl. At those points at which the
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fine pattern is to be represented the addresses of the
corresponding pattern array MF are represented by the
corresponding point code in character ar~ays ZFPl to ZFP3.
Expediently the text is input later by means of an
appropriate keyboard.
, Following the input, output is effected in
accordance with the illustration in Fig. 6. The scanned
-~ pattern Gl is represented as pattern G2 by the graphic
.,,
elements GE. Following the call-up of the corresponding
character arrays ZF in the write-read store by means of
the addresses represented by the point code, the patterns
G3 to G5 are represented as fine patterns and following
input by means of the keyboard the text is represented as
text T.
Further details of the apparatus will now be given
referring to Fig. 7. The arrangement illustrated in Fig. 7
contains an input unit E for the input of the graphic
patterns and the characters, a control unit SE which serves
to prepare the patterns and characters which are to be
represented, and an output unit AE which serves to provide
representations of the patterns and characters. The input
unit E contains a keyboard TA for the input of the characters
and a scanning unit A for the input of the ~atterns represented
on original plates V. The scanning unit A is followed by an
image store B in which each scanned graphic element GE is
stored.
The control unit SE contains a first converter UMl
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which on the one hand convexts the characters input by
means of the keyboard TA into corresponding code words CWl
and wnich on the other hand, on the input of a coarse pattern,
combines the graphic elements GE to form character arrays
ZF and assigns ~he latter corresponding code words CW2.
The converter UMl is followed by a store Sl which stores
the code words CWl and CW2 of one page i.e. of 960 character
~-~ arrays~ The control unit SE also contains a second converter
UM2 which in the event of the input of ine patterns combines
the n x m graphic elements GE to form a pattern array MF
and converts the graphic elements GE into pixels BP and the
pattern arrays MF into character arrays ZF. The pixels BP
are assembled to form data words DW, transferred to a store
S2, and stored therein under addresses determined by code
words CW0
The output unit AE likewise contains a store S3
in which the code words CW of one page may be stored and
further contains three character generators Zl to Z3. The
character generator Zl stores the possible combinations
of the graphic elements GE within a character array ZF.
The character generator Z2 contains the pixels BP of the
characters and the data words DW of the store S2 can be
input into the character generator Z3. In dependence upon
the code words CW stored in the store S3 and appropriate
switching signals, binary character sequences are read
out from the character generators Zl to Z3 and transferred
to an image control unit BST provided with a screen BS in
3~L
order to provide representations of the corresponding
patterns and characters.
If both coarse and fine patterns and characters are
to be represented by the output unit AE, firstly the original
plate V corresponding to Fig. 4 with the fine patterns
represented in enlarged form is scanned by means of the
scanning unit A. Via the image store B and the change-over
switch Ul whe~ in thebroken line position, corresponding
scanning signals are fed to the converter UM2 which produces
the data words DW assigned to the pixels BP from the scanned
graphic elements GE and stores these in the store S2 under
the appropriate addresses. Then an original corresponding
to Fig. 5 is scanned by means of the scanning unit A and
via the change-over switch Ul is fed to the converter UMl.
The latter produces the code words CW2 assigned to the
pattern Gl and stores these in the store Sl. The points in
f the character arrays ZFPl to ZFP3 are recognised by the
converter UM1 as addresses which represent the code words
CW3 and are stored by said converter, appropriately
characterised, in the store Sl. Then the text T is input via
the keyboard TA and in the converter ~Ml is converted into
corresponding code words CWl which are likewise stored in
the store Sl in a specially characterised fashion.
Prior to representation on the output unit AE the
content of the store S2 is transerred via the change-over
switch U2 (broken line position) to the character generator
Z3.
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Then the code words CW stored in the storP S1 are
transferred to the store 53 of the output unit AE. When the
pattern G2 is represented on the screen BS, the store S3
is connected via the change-over switch U3 to the character
generator Zl and the appropriate graphic elements GE are
rPpresented on the screen BS. In the case of the represen-
tation of the patterns G3 to G5 the change-over switch ~3
connects the store S3 to the character generator Z3 and ~he
~ fine patterns are represented. Then the store S3 is connected
via the change~over switch U3 to the character generator Z2
in order to represent the text T.
The output unit AE can form part of a television
device which is suitable for the "screen text" ("Video text
interactive") telecommunications service. In this case the
code words CW are transferred to the output unit AF via a
telephone line FL. The 'latter is connected to a central
control Z in which the contents of the stores Sl and S2
are normally stored ready for call-up. The input unit E
and the control unit SE are provided for those providing the
information who set up the pages which are to be called up.
The characters and 'the graphic patterns can be
represented in eight different colours. The desired colour
is characterised by appropriate switching signals. Expediently
the enlarged representation of the fine patterns takes
place in the particular desired colour so that the converter
UM2 can determine the particular colour of the corresponding
pattern array MF and character array ZF. The appropriate
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switching signal can be fed via a switch SW and the
converter UM1 to the store Sl where it is stored together
with the corresponding address of the character array ZF.
As it is not normally possible to modify the
colour within a character array ZF it can be expedient to
select _ and m to be such that the boundaries of the pattern
array MF coincide with the boundaries of the character
arrays ZF in order to prevent, as illustrated in Fig. 1,
individual character arrays ZF belonging to a plurality
ln of pattern arrays M~'. This is achieved for example when it
is selected that n = 8 and m = 12. In this case the pattern
array l~F comprises 4 x 4 character arrays ZF.
The switch SW enables the transfer of the code
words C~3 from th~ converter UM2 to the converter UMl so
that the enlarged form of the fine pattern can be displayed
as for a coarse pattern~
C` The apparatus described above has the advantage
that the same input means can be used for ~he fine graphic
pattern as for the coarse graphic pattern. The simultaneous
representation of a plurality of character arrays also
allows simple input and possible correc~ion of graphic
patterns which extend over several character arrays.
