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Claims  |
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What is claimed is:
1. An apparatus for producing dot-matrix data from outline data defining at
least one original outline of an alpha-numeric character or other symbol
in an image in a two-dimensional coordinate system provided by an X axis
and a Y axis perpendicular to each other, comprising:
first transforming means for transforming, according to transformation
data, first interval data defining a plurality of original intervals with
respect to at least one of said X axis and said Y axis, into second
interval data defining a plurality of transformed intervals with respect
to said at least one of said X axis and said Y axis;
correcting means for correcting, according to a first predetermined rule,
said second interval data into third interval data defining a plurality of
corrected intervals with respect to said at least one of said X axis and
said Y axis;
transformation-function determining means for determining, based on said
first interval data and said third interval data, a transformation
function for each of at least one of said original intervals defined with
respect to said at least one of said X axis and said Y axis;
second transforming means for transforming first outline data as said
outline data, into second outline data defining at least one transformed
outline of said image, said first outline data comprising a plurality of
original sets of x and y coordinates which cooperate with each other to
define said original outline of said image, said second outline data
comprising a plurality of transformed sets of x and y coordinates which
cooperate with each other to define said transformed outline of said
image,
said second transforming means transforming at least one of (a) an x
coordinate and (b) a y coordinate of at least one said original set of x
and y coordinates within said each of said at least one of said original
intervals defined with respect to said at least one of (a) said X axis and
(b) said Y axis, into at least one of (a) an x coordinate and (b) a y
coordinate of at least one said transformed set of x and y coordinates
within a corresponding one of said corrected intervals, according to said
transformation function determined for said each original interval;
dot-matrix data producing means for producing said dot-matrix data from
said second outline data according to a second predetermined rule, said
dot-matrix data comprising a plurality of sets of inside data
substantially defining an image area within said transformed outline of
said image defined by said second outline data, and a plurality of sets of
outside data substantially defining an outside area outside of said
transformed outline of said image; and
presentation means for presenting said dot-matrix data to an observer
corresponding to the alpha-numeric character or other symbol in the image.
2. An apparatus according to claim 1, wherein said presentation means
comprises a printing device which records, on a recording medium, said
image according to said dot-matrix data comprising said sets of inside
data and said sets of outside data defining picture elements of the image
to be recorded on the recording medium.
3. An apparatus according to claim 1, further comprising a dot-matrix data
memory which stores said dot-matrix data.
4. An apparatus according to claim 1, further comprising an original-data
memory which stores at least one of said first outline data and said first
interval data, said first outline data defining at least one original
outline of a character as said image, said original sets of x and y
coordinates of said first outline data comprising at least one of (a) a
set of x and y coordinates defining an end point of a straight line as a
portion of said original outline, and (b) a plurality of sets of x and y
coordinates defining at least one control point and an end point of a
Bezier curve as a portion of said original outline.
5. An apparatus according to claim 1, further comprising an input device
which is operable for inputting at least one of (a) said transformation
data and (b) at least one character code corresponding to at least one set
of character data as said first outline data and said first interval data
for at least one character as said image.
6. An apparatus according to claim 5, further comprising a parameter memory
which stores said at least one of (a) said transformation data and (b)
said at least one character code, (a) said transformation data comprising
at least one of (a1) size-related data relating to a size of said image
with respect to said at least one of said X axis and said Y axis and (a2)
a translation value indicative of a parallel-translation amount of said
image with respect to said at least one of said X axis and said Y axis.
7. An apparatus according to claim 6, wherein said parameter memory stores
(a) said transformation data including said (a1) size-related data
comprising a size value indicative of said size of said image with respect
to said at least one of said X axis and said Y axis.
8. An apparatus according to claim 1, further comprising reading means for
reading at least one of said first outline data, said first interval data,
and said transformation data.
9. An apparatus according to claim 1, wherein said first interval data
comprise at least one of (a) x position data including one original x
coordinate out of said original sets of x and y coordinates, (b) x spacing
data including two original x coordinates out of said original sets of x
and y coordinates, (c) y position data including one original y coordinate
out of said original sets of x and y coordinates, and (d) y spacing data
including two original y coordinates out of said original sets of x and y
coordinates.
10. An apparatus according to claim 9, wherein said first transforming
means comprises linear transformation means for transforming at least one,
v, of (a) said one original x coordinate as said x position data, (b) said
two original x coordinates as said x spacing data, (c) said one original y
coordinate as said y position data, and (d) said two original y
coordinates as said y spacing data, of said first interval data, into said
second interval data comprising at least one, v', of (a) one transformed x
coordinate corresponding to said one original x coordinate, (b) two
transformed x coordinates corresponding to said two original x
coordinates, (c) one transformed y coordinate corresponding to said one
original y coordinate, and (d) two transformed y coordinates corresponding
to said two original y coordinates, according to a linear function,
v'=Z.times.v+T, defined by said transformation data comprising a
transformation coefficient, Z, with respect to said at least one of said X
axis and said Y axis and a constant, T, with respect to said at least one
of said X axis and said Y axis.
11. An apparatus according to claim 10, wherein said linear transformation
means transforms said first interval data into said second interval data
according to said linear function, v'=Z.times.v+T, with respect to each of
(a) said X axis and (b) said Y axis, such that said transformation
coefficient Z is defined by a following expression:
Z=(p.times.d)/(I.times.e)
where
p is a desired size value of said image input through an input device;
d is a resolution of said image defined by said dot-matrix data;
e is an original size value of said image defined by said first outline
data; and
I is a constant,
so that each of said sets of inside data and said sets of outside data of
said dot-matrix data corresponds to a square unit area whose four vertices
are defined by two adjacent transformed x integral coordinates, x and x+1,
and two adjacent transformed y integral coordinates, y and y+1.
12. An apparatus according to claim 10, wherein said correcting means
comprises rounding means for correcting at least one of (a) said one
transformed x coordinate and (c) said one transformed y coordinate, of
said second interval data, into said third interval data comprising at
least one of (a) one corrected x coordinate corresponding to said one
transformed x coordinate and (c) one corrected y coordinate corresponding
to said one transformed y coordinate, according to said first
predetermined rule wherein each of said at least one of (a) said one
transformed x coordinate and (c) said one transformed y coordinate is
rounded, according to a predetermined rounding rule, to one of a number of
reference coordinates equidistant from one another by a unit distance with
respect to a corresponding one of said at least one of said X axis and
said Y axis, said one reference coordinate providing a corresponding one
of (a) said one corrected x coordinate and (c) said one corrected y
coordinate.
13. An apparatus according to claim 12, wherein said rounding means rounds,
according to said predetermined rounding rule, said each of said at least
one of (a) said one transformed x coordinate and (c) said one transformed
y coordinate, to one nearest thereto of said reference coordinates.
14. An apparatus according to claim 10, wherein said correcting means
comprises rounding means for correcting at least one of (b) said two
transformed x coordinates and (d) said two transformed y coordinates, of
said second interval data, into said third interval data comprising at
least one of (b) two corrected x coordinates corresponding to said two
transformed x coordinates and (d) two corrected y coordinates
corresponding to said two transformed y coordinates, according to said
first predetermined rule wherein one of the two transformed coordinates of
each of said at least one of (b) said two transformed x coordinates and
(d) said two transformed y coordinates which one transformed coordinate
satisfies a predetermined rounding condition regarding one of a number of
reference coordinates equidistant from one another by a unit distance with
respect to a corresponding one of said at least one of said X axis and
said Y axis, is rounded to said one reference coordinate as a first
reference coordinate and wherein the other of said two transformed
coordinates is changed to a second reference coordinate by a rounded
distance of said two transformed coordinates, said rounded distance being
equal to an integral number of said unit distances, said first and second
reference coordinates providing the two corrected coordinates
corresponding to said two transformed coordinates, respectively.
15. An apparatus according to claim 14, wherein said rounding means rounds
one of said two transformed coordinates which one transformed coordinate
satisfies a predetermined rounding condition that said one transformed
coordinate has a smaller distance up to one nearest thereto of said
reference coordinates than that of the other of said two transformed
coordinates.
16. An apparatus according to claim 10, wherein said correcting means
comprises means for correcting, according to said first predetermined
rule, at least one of (a) said one transformed x coordinate, (b) said two
transformed x coordinates, (c) said one transformed y coordinate, and (d)
said two transformed y coordinates, each of said second interval data,
into said third interval data comprising at least one of (a) one corrected
x coordinate corresponding to said one transformed x coordinate, (b) two
corrected x coordinates corresponding to said two transformed x
coordinates, (c) one corrected y coordinate corresponding to said one
transformed y coordinate, and (d) two corrected y coordinates
corresponding to said two transformed y coordinates.
17. An apparatus according to claim 16, wherein said
transformation-function determining means comprises means for determining,
as said transformation function for said each of said at least one of said
original intervals defined with respect to said at least one of said X
axis and said Y axis, a linear function, v'=a.times.v+b, wherein, when
said each original interval has two opposite ends respectively defined by
two adjacent original coordinates, p and q, out of (a) at least one said
one original x coordinate as said x position data, (b) at least one pair
of said two original x coordinates as said x spacing data, (c) at least
one said one original y coordinate as said y position data, and (d) at
least one pair of said two original y coordinates as said y spacing data,
said constants a, b of said linear function are as follows:
a=(q'-p')/(q-p)
b=(p'.times.q-q'.times.p)/(q-p)
where p' and q' are the two corrected coordinates corresponding to said two
original coordinates p, q, respectively.
and wherein, when said each original interval has only one end defined by
one, p, of a greatest and a smallest original coordinate out of (a) at
least one said one original x coordinate, (b) at least one pair of said
two original x coordinates, (c) at least one said one original y
coordinate, and (d) at least one pair of said two original y coordinates,
said constants a, b of said linear function are as follows:
a=Z
b=p'-p.times.Z
where
Z is a transformation coefficient with respect to said at least one of said
X axis and said Y axis, said transformation data comprising said
transformation coefficient; and
p' is the corrected coordinate corresponding to said one original
coordinate p.
18. An apparatus according to claim 1, wherein said dot-matrix producing
means comprises means for producing said dot-matrix data from said second
outline data according to said second predetermined rule wherein, when a
center of each of a number of rectangular unit areas each of which is
defined by (a) a consecutive two of a number of reference x coordinates
equidistant from one another by a first unit distance with respect to said
X axis and (b) by a consecutive two of a number of reference y coordinates
equidistant from one another by a second unit distance with respect to
said Y axis, falls inside said transformed outline of said image defined
by said second outline data, said each rectangular unit area is defined by
one said set of inside data and, when not, said each rectangular unit area
is defined by one said set of outside data, said first unit distance being
equal to a distance between two transformed x integral coordinates, said
second unit distance being equal to a distance between two transformed y
integral coordinates.
19. An apparatus according to claim 1, further comprising a
transformation-function memory which stores the transformation function
determined by said transformation-function determining means for each of
said original intervals defined with respect to said at least one of said
X axis and said Y axis, wherein after said transformation-function
determining means determines said transformation function for said each of
said original intervals and said transformation-function memory stores
said transformation function determined for said each of said original
intervals, said second transforming means transforms said at least one of
(a) said x coordinate and (b) said y coordinate of at least one said
original set of x and y coordinates within said each of said original
intervals, into said at least one of (a) said x coordinate and (b) said y
coordinate of at least one said transformed set of x and y coordinates
within said corresponding one of said corrected intervals, according to
said transformation function determined for said each of said original
intervals and stored in said transformation-function memory.
20. An apparatus according to claim 1, further comprising:
a transformation-function memory which stores said transformation
determined by said transformation-function determining means for said each
of said at least one of said original intervals defined with respect to
said at least one of said X axis and said Y axis; and
judging means for judging, for each of at least one of (a) an x coordinate
and (b) a y coordinate of each of said original sets of x and y
coordinates, whether said transformation-function memory stores the
transformation function determined for one of said original intervals
within which interval said each of said at least one of (a) said x
coordinate and (b) said y coordinate falls,
wherein when said judging means makes a negative judgment said
transformation-function determining means determines the transformation
function for said one of said original intervals within which interval
said each of said at least one of (a) said x coordinate and (b) said y
coordinate falls and said transformation-function memory stores said
transformation function determined for said one of said original
intervals, and when said judging means makes a positive judgment said
second transforming means transforms said each of said at least one of (a)
said x coordinate and (b) said y coordinate according to said
transformation function determined for said one of said original intervals
and stored in said transformation-function memory. |
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Claims |
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Description |
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an apparatus for producing dot data or
dot-matrix data from outline data defining one or more outlines of an
image such as a character.
2. Related Art Statement
There is known a data processing device which processes outline data
including a plurality of sets of point data, i.e., sets of x and y
coordinates which cooperate with each other to define, in the x-y
coordinate system, one or more outlines of an image such as a character
(e.g., letter, numeral, symbol, figure, etc.). The data processing device
produces dot-matrix data from the outline data, so that an output device
such as a printer or a display outputs the image according to the
dot-matrix data. The dot-matrix data include (a) a plurality of sets of
"ON" data (or "OFF" data) defining the inside area of the output image and
(b) a plurality of sets of "OFF" data (or "ON" data) defining the outside
area of the output image. Each set of "ON" or "OFF" data corresponds to a
unit area of the x-y coordinate system or plane, on one hand, and
corresponds to a picture element of the output image, on the other hand.
The process of producing dot-matrix data from outline data may easily be
understood by assuming a picture-element screen 31, as shown in FIG. 16,
which conceptionally defines the picture elements of an output image to be
produced by the output device. The picture-element screen 31 is
constructed by (a) a number of straight lines extending parallel to a Y
axis and passing through respective integral coordinates of an X axis
which is perpendicular to the Y axis and cooperates with the Y axis to
provide a two-dimensional coordinate system, and (b) a number of straight
lines extending parallel to the X axis and passing through respective
integral coordinates of the Y axis. In this case, each picture element of
the output image corresponds to a square unit area defined by (a) two
adjacent straight lines parallel to the Y axis and (b) two adjacent
straight lines parallel to the X axis, and those four straight lines
provide the four boundary lines of the square unit area.
A raster-scanning method using a picture-element screen is widely used for
producing dot-matrix data from outline data. This method will be described
in detail by reference to the outline data of a character "n" shown in
FIG. 2. First, the outline data, or outline defined thereby are assumed to
be superposed on the picture-element screen. Next, a single straight
scanning line is assumed to extend parallel to the X or Y axis and pass
over the centers of square unit areas of the picture-element screen, i.e.,
picture elements of the output image. Subsequently, all the intersecting
point or points of the scanning line and the character outline is/are
determined. Based on the position or positions of the intersecting point
or points, a set of "ON" or "OFF" data is given to each of the square unit
areas currently under the scanning line, according to a predetermined
rule, so that one or more sets of "ON" data substantially define the
inside area of the character outline and one or more sets of "OFF" data
substantially define the outside area of the character outline. Thus, one
row or one column of the dot-matrix data is produced. By repeating this
operation moving the scanning line all over the picture-element screen,
the entire dot-matrix data are produced for the character as a whole. In
this way, the dot-matrix data are produced from the outline data.
Alternatively, after the original or first outline data are transformed
into second outline data defining a transformed outline having a changed
size, the second outline data may be converted into dot-matrix data in the
same manner as described above. In this case, it is possible to obtain
various sizes of transformed outlines or images from a single set of
original outline data. The process of changing the size of an outline or
image defined by outline data will be described by reference to the
outline data of character "n" of FIG. 2. This process may be performed by
transforming the sets of point data, i.e., sets of x and y coordinates of
the outline data in such a way that each picture element of an output
image corresponds to a square unit area whose four vertices are defined by
two adjacent transformed x integral coordinates and two adjacent
transformed y integral coordinates. Assuming that a desired size of the
output image be selected at a value, p (points; p=1 is equal to 1/72
inch), by an operator or user through an input device such as a keyboard,
that the resolution of the output device be specified at a value, d (dots
per inch), and that the original size of the image be defined at a value,
e, by the original outline data, then a transformation coefficient, Z, for
the above coordinate transformation is obtained by the following
expression:
Z=(p.times.d)/(I.times.e)
where I is a constant, i.e., 72 (points per inch).
Additionally, the operator may input, through the input device, data
indicative of a desired position of the output image, i.e.,
parallel-translation amount of the image with respect to the X and/or Y
axis. Therefore, this coordinate transformation is generally expressed by
the following transformation function, i.e., linear function:
v'=Z.times.v+T
where Z is the transformation coefficient with respect to the X and/or Y
axis;
T is the parallel-translation amount with respect to the X and/or Y axis;
v is each of the x and/or y coordinates of the original outline data; and
v' is a corresponding one of the x and/or y coordinates of the transformed
outline data.
Hereinafter, the original outline data are referred to as the "outline data
A" and the transformed outline data are referred to as the "outline data
B".
If the outline data B are superposed on a picture-element screen 31 as
shown in FIG. 16 and subsequently the outline data B are subjected to the
raster-scanning method to produce dot-matrix data, the dot-matrix data
produced may suffer from low quality because quantization errors may occur
when the outline data B are converted into the dot-matrix data. FIG. 16
shows the dot-matrix data including the sets of "ON" data (indicated by
hatching) produced from the outline data B by the raster-scanning method.
As can been seen from the figure, vertical parts 33, 34 of the dot-matrix
data have different widths whereas the counter parts of the outline data B
have the same width. Thus, the dot image, i.e., output image may give a
strange impression to observers.
For solving the above problem, it has been practiced to automatically
adjust the position and width of a vertical or horizontal part of a
transformed image, and thereby control the number of picture elements to
be located between the two opposite outline portions of the vertical or
horizontal part. One of the known methods will be described below.
First, line-spacing data are prepared which include (a) position data
including two x or y coordinates defining a vertical or horizontal part to
be adjusted and (b) spacing data defining the distance between the two
coordinates. Thus, the line-spacing data define the width of the vertical
or horizontal part. More specifically, a set of x line-spacing data for a
vertical part includes (a) x position data including two x coordinates and
(b) x spacing data defining the difference or distance between the two x
coordinates. Similarly, a set of y line-spacing data for a horizontal part
includes (c) y position data including two y coordinates and (d) y spacing
data defining the difference or distance between the two y coordinates.
FIG. 2 shows the outline data A of character "n" for which two sets of x
line-spacing data are included for two vertical parts 20, 21 of the
character "n".
Second, the line-spacing data are transformed according to a desired size
of the output image. Regarding the character "n" of FIG. 2, the two x
coordinates of each of the two sets of x line-spacing data 20, 21 are
transformed by the same manner as used for the transformation of the
outline data A into the outline data B, and the distance or width defined
by the x spacing data of each set of x line-spacing data 20, 21 is
multiplied by the transformation coefficient Z, and then is rounded by
counting fractions of 0.5 and over as one and cutting away the rest, or
otherwise cutting away fractions smaller than one. The thus obtained width
will be referred to as the "dot width". The dot width just corresponds to
an integral number of dots, i.e., picture elements of the output image.
FIG. 16 shows the transformed sets of x line-spacing data 35, 36
respectively corresponding to the original sets of x line-spacing data 20,
21.
Third, one of the two transformed x coordinates of each transformed set of
x line-spacing data 35, 36 which one coordinate has a smaller distance up
to an x integral coordinate nearest thereto than that of the other
transformed coordinate, is selected as a base coordinate, and the other
transformed coordinate is selected as a dependent coordinate. The base
coordinate is moved, i.e., rounded to that integral coordinate nearest
thereto, which provides a corrected base coordinate. Otherwise, a smaller
one of the two transformed coordinates may be selected as a base
coordinate and be rounded to an integral coordinate as a corrected base
coordinate by cutting away fractions smaller than one. Then, the dependent
coordinate is moved to an integral x coordinate, i.e., corrected dependent
coordinate, distant from the corrected base coordinate by the dot width.
Subsequently, all the x coordinates of the outline data B equal to the
base coordinate are corrected or moved to the corrected base coordinate,
and all the x coordinates of the outline data B equal to the dependent
coordinate are corrected or moved to the corrected dependent coordinate.
FIG. 17 shows outline data C obtained by correcting the outline data B as
described above. The two sets of x line-spacing data 35, 36 of FIG. 16 are
corrected to two sets of x line-spacing data 413, 414 of FIG. 17,
respectively. In FIG. 17, black circles 40, 41, 42, 43, 44, 45, and 46
indicate the x coordinates corrected based on the transformed and
corrected x line-spacing data 35, 413, and black circles 47, 48, 49, 410,
411, and 412 indicate the x coordinates corrected based on the transformed
and corrected x line-spacing data 36, 414. The outline data C are
converted into dot-matrix data indicated by hatching in FIG. 17 wherein
the vertical parts 33, 34 of the dot-matrix data have the same width.
Thus, the dot-matrix data enjoy high quality.
In short, the outline data A are first subjected to size changing to
provide the outline data B, which in turn are subjected to correction of
quantization errors to provide the outline data C, which in turn are
subjected to the raster-scanning method using the picture-element screen
31 to provide the dot-matrix data.
In the above conventional process, however, it is not necessary, but
actually is carried out, to transform the original x coordinates
(indicated by black circles in FIG. 2) of the outline data A which are to
be corrected when the outline data B are corrected to the outline data C,
because those original x coordinates can be corrected without utilizing
the corresponding transformed x coordinates of the outline data B. This
applies to the original y coordinates to be corrected, if any. This
problem leads to increasing the production cost of the dot-matrix data and
lowering the production efficiency of the dot-matrix data.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide an apparatus
which produces dot-matrix data with high quality from outline data with
high production efficiency.
The above object has been achieved by the present invention, which provides
an apparatus for producing dot-matrix data from outline data defining at
least one original outline of an image in a two-dimensional coordinate
system provided by an X axis and a Y axis perpendicular to each other,
comprising: first transforming means for transforming, according to
transformation data, first interval data defining a plurality of original
intervals with respect to at least one of the X axis and the Y axis, into
second interval data defining a plurality of transformed intervals with
respect to the at least one of the X axis and the Y axis; correcting means
for correcting, according to a first predetermined rule, the second
interval data into third interval data defining a plurality of corrected
intervals with respect to the at least one of the X axis and the Y axis;
transformation-function determining means for determining, based on the
first interval data and the third interval data, a transformation function
for each of at least one of the original intervals defined with respect to
the at least one of the X axis and the Y axis; second transforming means
for transforming first outline data as the above-indicated outline data,
into second outline data defining at least one transformed outline of the
image, the first outline data comprising a plurality of original sets of x
and y coordinates which cooperate with each other to define the original
outline of the image, the second outline data comprising a plurality of
transformed sets of x and y coordinates which cooperate with each other to
define the transformed outline of the image, the second transforming means
transforming at least one of (a) an x coordinate and (b) a y coordinate of
at least one original set of x and y coordinates within the each of the at
least one of the original intervals defined with respect to the at least
one of (a) the X axis and (b) the Y axis, into at least one of (a) an x
coordinate and (b) a y coordinate of at least one transformed set of x and
y coordinates within a corresponding one of the corrected intervals,
according to the transformation function determined for the each original
interval; and dot-matrix data producing means for producing the dot-matrix
data from the second outline data according to a second predetermined
rule, the dot-matrix data comprising a plurality of sets of inside data
substantially defining an inside area of the transformed outline of the
image defined by the second outline data, and a plurality of sets of
outside data substantially defining an outside area of the transformed
outline of the image. The original interval data define a plurality of
original intervals with respect to each of the X and Y axes of the x-y
coordinate system in which the original outline of the character is
defined by the original outline data. This data contains (a) one or more
sets of position data each set of which includes a single x (or y)
coordinate, and (b) one or more sets of spacing data each set of which
includes a pair of x (or y) coordinates. A set of position data is used
for positional alignment of a character with respect to the X (or Y) axis
and a set of spacing data is used for adjusting the number of square unit
area or areas (i.e., picture element or elements) to be located between a
pair of transformed x (or y) coordinates. This information comprises hint
data which will be described in detail.
In the dot-matrix data producing apparatus constructed as described above,
the first transforming means transforms the first interval data defining a
plurality of original intervals, into second interval data defining a
plurality of transformed intervals, the correcting means corrects the
second interval data into third interval data defining a plurality of
corrected intervals, and the transformation-function determining means
determines, based on the first and third boundary data, a transformation
function for each of the original intervals. The correction of the second
interval data to the third interval data is effected for compensating for
quantization errors that has possibly been introduced into the second
interval data. The second transforming means transforms the x and/or y
coordinate of at least one original set of x and y coordinates within each
of the original intervals, into the x and/or y coordinate of at least one
transformed set of x and y coordinates within a corresponding one of the
corrected intervals, according to the transformation function determined
for each original interval. Thus, the x and/or y coordinates of the
transformed sets of x and y coordinates of the second outline data are
free from the quantization errors, therefore the second outline data enjoy
excellent quality. Additionally, the first transforming means does not
transform all the original x and/or y coordinates that need the
quantization-error correction. Thus, the present apparatus enjoys improved
production efficiency of the dot-matrix data. Furthermore, since the
transformation function is determined for each of the original intervals,
the second outline data are free from the problem that visual balance or
smoothness of the image may be lost at the transition or transitions from
one interval to its adjacent interval or intervals.
According to a preferred feature of the present invention, the dot-matrix
data producing apparatus further comprises an output device which outputs
the image according to the dot-matrix data. The output device may be a
printing device, such as a laser printer, or a displaying device, such as
a liquid-crystal display. The printing device may record, on a recording
medium, the image according to the dot-matrix data comprising the sets of
inside data and the sets of outside data each set of which corresponds to
a picture element of the image to be recorded on the recording medium.
Each set of inside data may indicate the presence of an image and each set
of outside data may indicate the absence of the image, or vice versa.
According to another feature of the present invention, the apparatus
further comprises an original-data memory which stores at least one of the
first outline data and the first interval data, the first outline data
defining at least one original outline of a character as the image, the
original sets of x and y coordinates of the first outline data comprising
at least one of (a) a set of x and y coordinates defining an end point of
a straight line as a portion of the original outline, and (b) a plurality
of sets of x and y coordinates defining at least one control point and an
end point of a Bezier curve as a portion of the original outline. In the
case where the original outline of the image consists of a plurality of
straight lines connected to each other, one of the two end points of each
of the connected straight lines defines one of the two end points of the
preceding or following straight line. In the case where the original
outline consists of a plurality of Bezier curves connected to each other,
one of the two end points of each of the Bezier curves defines one of the
two end points of the preceding or following Bezier curve. In the case
where a Bezier curve is defined by a quadratic Bezier function, the Bezier
curve has a single control point; and in the case where a Bezier curve is
defined by a cubic Bezier function, the Bezier curve has two control
points.
According to yet another feature of the present invention, the apparatus
further comprises an input device which is operable for inputting at least
one of (a) the transformation data and (b) at least one character code
corresponding to at least one set of character data as the first outline
data and the first interval data for at least one character as the image.
In this case, the apparatus may further comprise a parameter memory which
stores the at least one of (a) the transformation data and (b) the at
least one character code, the transformation data comprising at least one
of (a1) size-related data relating to a size of the image with respect to
the at least one of the X axis and the Y axis and (a2) a translation value
indicative of a parallel-translation amount of the image with respect to
the at least one of the X axis and the Y axis. The size-related data may
comprise a size value indicative of the size of the image with respect to
the at least one of the X axis and the Y axis. The size value may be a
point number, p (points; p=1 is equal to 1/72 inch). Otherwise, the
size-related data may be a reduction or magnification factor (e.g., 1/2,
2).
According to a further feature of the present invention, the first interval
data comprise at least one of (a) x position data including one original x
coordinate out of the original sets of x and y coordinates, (b) x spacing
data including two original x coordinates out of the original sets of x
and y coordinates, (c) y position data including one original y coordinate
out of the original sets of x and y coordinates, and (d) y spacing data
including two original y coordinates out of the original sets of x and y
coordinates.
According to another feature of the present invention, the first
transforming means comprises linear transformation means for transforming
at least one, v, of (a) the one original x coordinate as the x position
data, (b) the two original x coordinates as the x spacing data, (c) the
one original y coordinate as the y position data, and (d) the two original
y coordinates as the y spacing data, of the first interval data, into the
second interval data comprising at least one, v', of (a) one transformed x
coordinate corresponding to the one original x coordinate, (b) two
transformed x coordinates corresponding to the two original x coordinates,
(c) one transformed y coordinate corresponding to the one original y
coordinate, and (d) two transformed y coordinates corresponding to the two
original y coordinates, according to a linear function, v'=Z.times.v+T,
defined by the transformation data comprising a transformation
coefficient, Z, with respect to the at least one of the X axis and the Y
axis and a constant, T, with respect to the at least one of the X axis and
the Y axis.
According to yet another featur | | |
