JPH0127430B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention provides a CRT phototypesetting machine, a laser printer,
Regarding a character image data processing device that supplies character image data to a scanning type character generating device such as a display device, in particular, image starting point information and non-image starting point information on each scanning line necessary for character image generation are optional. An object of the present invention is to provide a character image data processing device which can handle the case where characters are supplied in this order with a small capacity memory.

It is well known that binary data obtained by dot decomposition of characters and images (hereinafter referred to as character images) has extremely high redundancy. Therefore, various data compression methods have been proposed to reduce this redundancy.

One such data compression method is the so-called contour method, which compresses the amount of data by understanding the shape of a character image using its outline and storing information specifying the outline.

FIG. 1 is a diagram explaining an example of a data compression method using the contour method, in which character image 1 is
Contour pixels in the Y direction when expanded in a matrix are schematically shown. In the figure, the pixels marked with ◯ indicate image start pixels (hereinafter also referred to as on-side pixels) when the Y direction is the main scanning direction, and the pixels marked with △ indicate non-image start pixels (hereinafter also referred to as on-side pixels). (also called off-side pixels).

As is clear from FIG. 1, these pixels form a series of pixel columns A, B, C, or D in the X direction (sub-scanning direction). Therefore,
The section of each pixel row is considered as one block,
By appropriately approximating the shape with a straight line or curve, and storing data for specifying the approximated straight line or curve as character image information, the character image can be stored in a small capacity.

Figure 2 shows, for example, the above character information.
A conventional configuration for restoring the original character image on the CRT display device 2 is schematically shown.

That is, first, the character information is retrieved from the character information storage section 3 which stores a plurality of character images as outline information, and sent to the decoding section 4. The decoding section 4 decodes the character information and calculates the coordinates of each contour point for each block. The calculated contour point information is supplied to the beam on-off point storage section 5, and is expanded and stored on a bitmap as shown in FIG. 3, for example. In the figure, the points indicated by bit "1" are the points corresponding to beam on or off. The beam control signal generating section 6 turns on the beam developed in the storage section 5.
Outputs a beam control signal based on off point information,
Plays character images by controlling the CRT2 beam on and off.

However, as in the conventional example shown in FIG. 3, a large capacity memory is required to develop contour points directly on a bitmap. For example, if one character image is represented by 2000 x 2000 pixels in order to maintain high print quality, 500 Kbytes of memory is required.

The present invention has been achieved based on the above points, and is characterized by reading and decoding contour information corresponding to a predetermined character image from a character image information storage unit that stores a plurality of character images as contour information. In a character image data processing device, the pixel coordinates X, Y information on the decoded contour is sent to a scanning output unit, and the character image is reproduced by turning on and off the beam. When X, Y information is sent, the storage area is accessed by the X address of the pixel coordinates on the on side, and the Y address of the on side contour coordinates is accessed by the X address of the pixel coordinates on the off side. a memory that stores Y addresses of off-side contour coordinates in a storage area; a counter that increments in accordance with the deflection position in the main scanning direction of the beam of the scanning output section; When the Y address read from the X address of the memory corresponding to the deflection position in the scanning direction matches, a comparator outputs a matching signal, and based on the matching signal, the Y address of the on-side contour coordinate matches. When the beam is on, the off-side contour coordinate Y
The present invention includes a deflection control circuit for a scanning output section that controls the beam to be turned off when the addresses match.

The present invention will be explained in detail below using the drawings.

FIG. 4 is a schematic diagram showing the configuration of the decoding section 4 related to the data processing apparatus according to the present invention. That is,
The outline information of the character image as described above is supplied from the character information storage unit 3 to the decoding unit 4 in units of blocks, and the coordinate information of each outline pixel obtained by the decoding unit 4 is transmitted to the beam on-off as shown in FIG. Output to point storage section 5.

At this time, if one processor performs the decoding process, it will take a relatively long time to decode a single character image consisting of a plurality of blocks.

Therefore, in order to process the decoding of multiple blocks in parallel, multiple processors are installed as shown in Figure 4.
a, 4b, .

In this embodiment, it is assumed that each piece of pixel information is sent in a state in which it is possible to identify whether it is contour information that corresponds to an on-side block or an off-side block.

FIG. 6 is a diagram showing an embodiment of the character image data processing device of the present invention.

In FIG. 6, 16 is a memory in which coordinate information of on-side pixels sent via bus 17 is written, and 18 is a memory in which coordinate information of OFF-side pixels sent via bus 19 is written. The memories 16 and 18 are composed of a plurality of storage areas that are accessed in a matrix.

In the following, for convenience of explanation, the address of each storage area accessed in the matrix is expressed as x,
Express as y. Furthermore, areas x and n expressed in this way mean n storage areas accessed by address x.

Then, a plurality of storage areas x, in which the X coordinate value of the supplied contour coordinate information is selected as the X address,
Of n, in the area of y address specified separately,
The Y coordinate information of the supplied contour itself is written.

Therefore, in the illustrated row direction (Y direction), 1
The number of areas Y(n) may be determined by assuming the maximum number of outlines of a character image that appear per scanning line.

20-1, 20-2 are X of memories 16, 18
A memory marker (hereinafter abbreviated as marker) having the same address as the address, 20-1 is an on-side marker, and 20-2 is an off-side marker. Markers 20-1 and 20-2 store how many pieces of coordinate information are written in the storage area corresponding to the X address.

When writing coordinate information to memories 16 and 18,
Marker 20-1 of the first corresponding X address,
Or read the contents of 20-2 respectively, read out how many pieces of coordinate information have been written in the storage area of the X address up to now, write the newly sent coordinate information to the next storage area, and The content of 20-1 or 20-2 itself is counted up by one.

When reading coordinate information from the memories 16 and 18, first read the marker 20-1 or 20-2 to check whether coordinate information is written in the storage area, and then read the marker 20-1 or 20-2.
The coordinate information of the number of areas written in is read out from the memories 16 and 18.

Furthermore, 21 is a register that reads and stores the contents of each storage area of the X address corresponding to the scanning line of CRT2 in memory 16 or 18, 22 is a comparator, 12 is a deflection control circuit that turns on and off the beam of CRT2, Reference numeral 13 denotes a step counter in accordance with the deflection position of the beam of the CRT 2 in the main scanning direction (Y coordinate).

As mentioned above, the contour coordinate information is sequentially sent from the decoding unit 4 starting from the blocks for which calculation processing has been completed, but the order is completely random.

Taking Figure 1 as an example, a set of paired ons,
Blocks indicating off, that is, they are not sent in the order of A, B, C, D, but for example, B, C,
It is also possible that D and A are sent in that order.

Therefore, the memory 16 stores Y(1) and Y(1) for each X address in the order in which the contour information of the on-side block is sent.
(3)..., the memory 18 stores Y for each X address in the order in which the contour information of the off-side block is sent.
(2), Y(4)..., are stored starting from the beginning.

In the following explanation, a case will be explained in which the contour coordinate information shown in FIG. 1 is sent from the decoder 4 in the order of blocks B, C, D, and A.

First, regarding off-side block B,
b ₁ is sent via bus 19. Since the X address of pixel b ₁ is X ₄ , off side marker 2
The contents of address _X4 of 0-2 are read out, but in this case, since this is the first coordinate information, information indicating that there is no data stored in the corresponding storage area is read out.

Therefore, the Y coordinate value “Y ₆ ” of pixel b ₁ is stored in the first storage area Y(2) where the off information of address X ₄ is stored.
is written.

At the same time, address _X4 of off-side marker 20-2 is set to address _X4 of off-side memory 18.
This information is rewritten to indicate that the data for each item has been written.

Next, when the coordinate information of pixel b ₂ is sent, since this is also off-side information, it is written into the storage area Y(2) at address X ₅ through the same processing as that for pixel b ₁ .

At the same time, the address _X5 of the off-side marker 20-2 is set to ₁ at the address
This information is rewritten to indicate that the data for each item has been written. In this way, all contour coordinate information of block B is written into storage area Y(2).

Assume that after block B has been written to each storage area of the memory 18 as described above, the information of block C is sent next.

Since each pixel of block C is a pixel of the on-side block, its coordinate information is sent via bus 17. Then, in the same way as in the case of block B, the coordinate information is the address of storage area Y(1).
Written since _X5 .

In the same manner, the coordinate information of block D is written in the off-side memory 18 and the coordinate information of block A is written in the on-side memory 16 at the positions shown in FIG.

Also, the contents of markers 20-1 and 20-2 are
As shown in the figure, information indicating the number of data stored in the storage area of each X address is written.

Next, based on the coordinate information of the character outline written in the memories 16 and 18, character image 1 in FIG.
Data processing when playing back on the CRT2 shown in the figure will be explained.

First, the contents of the on-side marker 20-1 are read, and the X address where the coordinate information is written is searched for in the storage area of the memory 16. here is the address
Since X ₄ appears first, the coordinate information written in the storage area of address X ₄ is transferred to the register 21 and stored therein.

Therefore, the Y coordinate value of pixel _a1 is transferred to and stored in register 21-1.

The deflection control circuit 12 sets the start position and _coordinates (X ₄ ,
control to start scanning from Y ₁ ).

When the beam is located at (X ₄ , Y ₁ ), the value of the counter 13 is “Y ₁ ”. The comparator 22 compares the contents of the register 21 and the contents of the counter 13, but since there is no match, no match signal is output. Therefore, the CRT2 beam will not turn on.

Next, the beam moves to (X ₄ , Y ₂ ), and the counter 13 becomes "Y ₂ ". However, as described above, since there is no register 21 whose value matches the contents of the counter 13, the comparator 22 does not output a match signal.

Next, when the beam comes to (X ₄ , Y ₃ ), the counter 13 becomes “Y ₃ ” and is compared with the contents of the register 21. This time, since the Y coordinate information of pixel a ₁ stored in register 21-1 is "Y ₃ ",
Comparator 22-1 outputs a coincidence signal. The match signal is sent to flip-flop 15 through OR circuit 14, flip-flop 15 is inverted, and CRT2
The beam turns on at the point (X ₄ , Y ₃ ).

Here, the contents of the address _X4 of the marker 20-1 count down by one and become "0", and the address _X1 of the memory 16 is rewritten to the information that there is no on-side coordinate information.

When the on-side coordinate information is output, the off-side information is always selected next, and the off-side marker 20-2
The contents are read to detect whether coordinate information is written in the off-side storage area. And the coordinate information of the address _X4 of the memory 18 on the off side, that is,
The Y coordinate value of pixel _b1 is transferred to register 21-1.

Even if the beam moves to (X ₄ , Y ₄ ), there is no register 21 that matches the contents of the counter 13, so
Comparator 22 does not output a match signal. accordingly
The CRT2 beam remains on. Similarly, the beam remains on at (X ₄ , Y ₅ ).

When the beam arrives at (X ₄ , Y ₆ ), the counter 13 becomes “Y ₆ ”, and a signal that matches the Y coordinate information “Y ₆ ” of pixel b ₁ set in the register 21-1 is sent to the comparator 22-1. Output from 1.

The match signal reverses flip-flop 15;
The CRT2 beam is turned off.

Here, address of off side marker 20-2 x ₄
counts down by one, and its value becomes "0".

In this way, the two markers 20-1,
20-2 both become "0", it is detected that no image signal exists even if the CRT2 beam is scanned at X ₄ , and at that point the next address is
Scanning starts from the beginning position of X ₅ (X ₅ , Y ₁ ).

On the other hand, the memory area where the coordinate information is written is detected again by the on-side marker 20-1.

The contents of each storage area at address _X5 of the on-side memory 16 are transferred, and the Y coordinate information of _c1 and pixel _a2 are stored in the register 21-1 and the register 21-2, respectively.

By repeating the processes described above, a character image is reproduced on the screen of the CRT 2, as shown in FIG. The portion marked with ◯ is the character pixel portion, and the portion marked with △ is the point where the beam turns from on to off.

In the above embodiment, the outline pixel information of the character image is sent block by block, but the present invention is not limited to this. It is clear that this method can also be applied to other data processing methods.

Further, in this embodiment, a case has been described in which a character image is reproduced on a CRT2, but it goes without saying that the present invention can also be applied to other output means such as a laser printer.

As explained in detail above, when the present invention reproduces the contour coordinate information of a character image decoded by the decoding unit on a CRT, the Y coordinate information sent as is is stored in an appropriate storage area with the X coordinate information as an address. In addition, the storage status of multiple storage areas corresponding to the same X address is managed using markers.

Furthermore, from the contour pixel information stored in this way,
When reproducing a character image on a CRT, the X address where coordinate information exists is searched based on the contents of the marker, the beam is scanned from the first position of the X address, and the randomly stored coordinate information is rearranged in advance. The system was designed so that text images can be played directly on a CRT, etc., without having to do so.

As a result, the present invention requires less memory capacity to store, and can handle the outline pixel information of the character outline without rearranging the outline pixel information, no matter what order the outline pixel information is sent. This has great effects such as shortening processing time.

[Brief explanation of drawings]

Figure 1 is a diagram explaining the outline of a character image, Figure 2 is a diagram explaining the conventional method, Figure 3 is a diagram showing the outline information of the character image developed on a bit map, Figure 4 is a diagram showing the decoding unit, FIG. 5 is a diagram for explaining the character image reproduction state on the CRT tube surface, and FIG. 6 is a diagram showing an embodiment of the present invention. 2...Decoding unit, 12...Deflection control circuit, 13...Counter, 15...Flip-flop, 16, 18...Memory, 20...Marker, 21...Register, 22...
Comparator.

Claims (1)

[Claims] 1. Outline information corresponding to a predetermined character image is read out from a character image information storage unit that stores a plurality of character images as outline information, and pixel coordinate (X, Y) information on the decoded outline is read out. The decoded pixel coordinate (X, Y) information on the contour is sent to a character image data processing device that reproduces the character image by turning on and off the beam. When, X of the pixel coordinates on the on side
a memory that stores the Y address of the on-side contour coordinates in a storage area accessed by the address, and the Y address of the off-side contour coordinates in a storage area accessed by the X address of the off-side pixel coordinate; a counter that increments according to the deflection position of the beam in the main scanning direction of the mold output section; and a Y address read from the X address of the memory corresponding to the deflection position of the beam in the sub-scanning direction, When they match, a comparator outputs a matching signal; Based on the matching signal, the beam is turned on when the Y address of the on-side contour coordinates matches, and the beam is turned on when the Y address of the off-side contour coordinates matches. A character image data processing device comprising: a deflection control circuit for a scanning output section that is controlled to be turned off;