JPH08195889A - Color printer - Google Patents

Abstract

PURPOSE: To provide a color printer capable of developing and printing complicated printing data even with a little memory amount which is made inexpensive by reducing the memory capacity. CONSTITUTION: In this color printer for performing color printing by using the ink of cyan, magenta, yellow and black, when a work memory 51 is insufficient for developing data, the data of the page memory 55 of black are synthesized with the respective page memories 52 to 54 of cyan, magenta and yellow and the page memory 55 of black is opened and changed to the work memory 51. Then, the data are read from the page memories 52 to 54 for the three colors of cyan, magenta and yellow and the printing is performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color printing apparatus for performing color printing with four colors of cyan, magenta, yellow and black.

[0002]

2. Description of the Related Art Conventionally, a color printing apparatus typified by an ink jet printer or the like for performing color printing using four color inks of cyan, magenta, yellow, and black has each print head of four colors. When printing print data sent from an external device such as a host computer, the print data is expanded into image image data corresponding to print pixels in a one-to-one correspondence, and the image image data is printed in each of four colors. Printing is being performed by sending it to the head. As described above, since image image data is required for the number of heads corresponding to the number of colors of the printing apparatus, a memory called a page memory is provided for storing the image image data of these four colors. Further, in order to expand the print data into the image image data, many complicated operations are required, and a memory called a work memory for storing the data to be operated and the operation result is also provided.

[0003]

However, a printing apparatus that performs color printing using such four color inks requires a large-capacity memory. For example, 300 dp
A4 by printing device with resolution of i (pixels / inch)
In order to print on size paper, even if one pixel is set to 1 bit, the image image data for each color is 1 Mbyte. Therefore, in order to store the image image data for four colors, 4 Mbyte is required only in the page memory. Next to
A large-capacity work memory is also required to develop complicated print data that uses many colors. Providing these large-capacity memories has been a major factor in increasing the cost of the printing apparatus. Further, it is conceivable to reduce the amount of memory in order to reduce the cost of the printing apparatus, but since a certain amount of page memory is required, the amount of work memory will be reduced. However, in such a case, it becomes impossible to expand print data that requires a large capacity work memory for expansion into image image data, and such print data cannot be printed. The present invention has been made in order to solve the above-mentioned problems, and when the memory capacity of the work data storage means is insufficient due to complicated expansion of print data or the like, a part of the page memory is used as a work memory. It is an object of the present invention to provide a color printing apparatus which is inexpensive and is capable of expanding complicated print data without increasing the total amount of memory required in the printing apparatus.

[0004]

In order to achieve this object, a color printer according to a first aspect of the present invention develops print data consisting of character codes and the like into image image data, and the image image data is cyan and magenta. A color printing apparatus for performing color printing with four colors of yellow, yellow, and black, and a data expansion unit for expanding print data into image image data, and a data expansion unit for generating data necessary for expansion of print data. Work data storage means for storing, image data storage means for storing each image data of cyan, magenta, yellow, and black developed by the data developing means, and a memory for determining a shortage of work data storage means When the shortage determination means and the memory shortage determination means determine that there is insufficient memory,
Work the image data combining means for combining the black image image data stored in the image data storing means with the cyan, magenta, and yellow image image data and storing it in the image data storing means, and the black image data storing means. And a memory changing means for changing to a data storing means. According to a second aspect of the present invention, there is provided a color printing apparatus according to the first aspect, in which cyan, magenta and black image data stored in the image data storage means are combined,
And image data separating means for separating the black image image data from the respective yellow and yellow image image data. Further, in the color printing apparatus of the third aspect of the invention, in the configuration of the second aspect, when the black image data storage means is changed to the work data storage means and high-speed printing is performed, the black printing is performed. When cyan, magenta, and yellow image image data combined with the image image data are read and printing is performed in three colors and high-speed printing is not performed, the image data separating means separates the black image image data. Then, printing is performed in four colors.

[0005]

According to the color printing apparatus of the present invention having the above-mentioned structure, the data expanding means stores the work data, which is sequentially required for expanding the print data including the character code into the image data, into the work data storing means. While storing the image data, the image image data having information corresponding to the print pixels in a one-to-one correspondence is developed, and the developed image image data is stored in each of the cyan, magenta, yellow, and black image data storage means. At this time, the memory shortage determination means determines whether or not the work data storage means runs short due to complicated print data expansion, and if it is determined that the memory is insufficient, the image data synthesis means causes the image data storage means to run. The black image image data stored in the image data storage means is combined with the cyan, magenta, and yellow image image data stored in the image data storage means and stored in the image data storage means. And
The memory changing means changes the storage area for black image data of the image data storing means to the working data storing means. As a result, the capacity of the work data storage means can be increased. Further, in the color printing apparatus according to the present invention, the image data separating means may store cyan, magenta, and
And the black image image data stored in the image data storage means is separated from the yellow image image data. This enables color printing with four colors. Further, in the color printing apparatus of claim 3, when high speed printing is performed when the black image data storage means is changed to the work data storage means, cyan, magenta, and When each yellow image image data is read out and printed in three colors and high-speed printing is not performed, the image data separating means separates the black image image data and prints in four colors. This makes it possible to deal with high quality printing and high speed printing.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A color printing apparatus according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a color printing apparatus according to this embodiment. The color printing apparatus 1 includes a CPU 2 that controls the entire apparatus, an interface 3 that receives print data including a character code and the like from an external device such as a host computer, a print engine 4 that prints on paper, and a print engine that occurs during operation of the apparatus. The RAM 5 is a volatile memory for storing data that needs to be temporarily stored, and the ROM 6 is a non-volatile memory in which various programs are stored. The CPU 2 is connected to the above-mentioned units and reads out the program from the ROM 6 to perform a predetermined operation.

The RAM 5 is created by a work memory 51, which is work data storage means for storing data that needs to be temporarily stored when the data expansion program 61 described later operates, and the data expansion program 61. A cyan page memory 5 which is an image data storage unit for storing one page of image image data for each color of cyan, magenta, yellow, and black.
2, a magenta page memory 53, a yellow page memory 54, and a black page memory 55 are provided.

The ROM 6 has a data expansion program 61, which is a print data expansion unit for expanding the print data received by the interface 3 into image image data.
And a work memory shortage determination program 62 which is a memory shortage determination means for checking whether or not the work memory 51 required for the operation of the data expansion program 61 runs short, and image image data stored in the black page memory 55. A page data synthesizing program 63 which is image data synthesizing means for synthesizing the image data with the cyan page memory 52, the magenta page memory 53, and the yellow page memory 54, and the black page memory 55 as a work memory. A work memory changing program 64, which is a memory changing means for changing to 51, and a cyan page memory 52,
A page data separation program 65, which is an image data separation means for separating black image image data from the image image data stored in each of the magenta page memory 53 and the yellow page memory 54, is provided.

Next, the image image data will be described with reference to FIG. FIG. 2A is a diagram showing an example of print data 201 (text data) including character codes,
(B) is a diagram showing a graphic 202 in which the print data 201 is allocated on coordinates, (c) is a diagram showing bitmap data 203 stored in a page memory, and (d) is a diagram showing a print output 204. e) is a diagram showing the data 205 stored in the work memory 51. The image data is the bitmap data 203 for the print output 204.
Is bitmap data having a bit corresponding to a print pixel in a one-to-one manner, and each page memory is printed paper 1
It has the capacity to store the image data corresponding to one sheet. The print data 201 of this example is
The two values before on specify the drawing position of the figure, the rect specifies the rectangular shape, and the two values before rect represent the width of the rectangle and the height of the rectangle in order. It is instructed to draw a quadrangle having a width of 5 pixels and a height of 3 pixels at the position (2, 2).

Next, the operation of the color printing apparatus 1 configured as described above will be described focusing on the operation of the data expansion program 61. As shown in FIG. 2, print data 2
Reference numeral 01 is text data including position, shape, and color elements. For example, a rectangle with a width of 5 pixels and a height of 3 pixels is drawn in blue at the position of coordinates (2, 2) like the figure 202. I'm telling you. When such print data is sent from an external device such as a host computer through the interface 3, the CPU 2 causes the print data expansion program 61, the work memory shortage determination program 62, the page data composition program 63, and the work memory in the ROM 6 to be stored. The change program 64 is activated to expand the print data into image image data.

FIG. 3 is a flow chart of the expansion processing to image image data. When the CPU 2 receives data from the interface 3 (step S1), it is checked whether or not the received data is a command to start printing (S2), and if the received data is not print start command but print data (S2. No), the print data is sent to the data expansion program 61, and the work memory 51 is used when the print data is expanded based on the position and shape elements of the print data.
The total amount of data (work data amount) to be stored in is calculated (S3), and the calculation result is sent to the work memory shortage determination program 62.

The work memory shortage determination program 62 is
The usable memory amount of the work memory 51 is compared with the sent work data amount (S4). If the work data amount is less than or equal to the usable memory amount of the work memory 51 (S4
(YES), the process is returned to the data expansion program 61 to perform the print data expansion process (S5). If the work data amount exceeds the usable memory amount (S4, NO), the work memory change program 64 checks whether the black page memory 55 is used as the work memory 51 (S7). If the black page memory 55 is already used as the work memory 51 (S7.
YES), since the work memory 51 cannot be increased, an error message indicating that the work memory is insufficient is generated and the process ends (S11). Still black page memory 5
5 is not used as the work memory 51 (S7
-NO), the available memory amount of the work memory 51 and the memory amount of the black page memory 55 are totaled and compared with the work data amount (S8). Even when the total amount of memory does not reach the amount of work data (S8, NO), an error message of insufficient work memory is generated and the process ends (S1).
1).

When the sum of the usable memory amount of the work memory 51 and the memory amount of the black page memory 55 exceeds the work memory amount (YES in S8), the page data synthesizing program 63 synthesizes the image data (S9). ). The page data composition program 63 reads the image image data from the black page memory 55, takes the logical sum (OR) with the image image data read from the cyan page memory 52, and returns the result to the cyan page memory 52. The same operation is performed for the image image data in the magenta page memory 53 and the yellow page memory 54, and the black image image data is combined with the cyan, magenta, and yellow image image data. Next, the work memory change program 64 clears the contents of the black page memory 55 and incorporates it into the work memory 51 (S10),
After that, the black page memory 55 is made available as a part of the work memory 51, the process is returned to the data expansion program 61, and the print data expansion process is continued (S5).

FIG. 4 is a flowchart of the print data expansion process (S5). The same process will be described below. The drawing start point and the drawing end point in the vertical direction are calculated from the position and shape elements of the print data (S101) and stored in the work memory 51. Next, from the start point to the end point in the vertical direction, it is repeated (S102), the drawing start point and the drawing end point in the horizontal direction at each position are calculated (S103), and the calculation results are successively stored as raster data in the work memory. 51 is stored.

Next, the page memory to which the bit-mapped data is written is selected from the color elements of the print data. First, the black page memory 55 is the work memory 5
It is checked whether it is used as 1 (S104), and if it is not used (S104, NO), the color of the print data is separated into four color components of cyan, magenta, yellow, and black (S105). ), The writing destination of the expanded image data is the cyan page memory 52,
Magenta page memory 53, yellow page memory 5
4 and the black page memory 55.
When the black page memory 55 is used as the work memory 51 (YES in S104), the color of the print data is color-separated into three color components of cyan, magenta, and yellow (S106), and the developed image is displayed. The write destination of the image data is selected from the cyan page memory 52, the magenta page memory 53, and the yellow page memory 54. Depending on the color, a plurality of page memories may be simultaneously selected regardless of the color separation of four colors and the color separation of three colors.

Further, the raster data in the work memory 51 is read and repeated from the start point to the end point in the vertical direction (S107), and is selected in step S105 or step S106 corresponding to the drawing start point and the drawing end point in the horizontal direction. The bit of "1" is set to the position on the selected page memory, and the bit of "0" is set to the page memory which is not selected (S108). Through the above processing, image image data is generated on each page memory.

Next, a specific operation of the print data expansion processing (S5) will be described by taking the case of the print data 201 (FIG. 2) as an example. The content of the print data 201 is as described above. When this print data 201 is input, the drawing position "2" is added as the start point and the drawing position is added as the end point, and "1" is subtracted in step S101. “4” is stored in the work memory 51 as a drawing range in the vertical direction. Next, by the loop of steps S102 and S103, step S103 is executed for each of the three points of ordinates "2" to "4", which is the drawing range in the vertical direction, and the horizontal direction is applied to each point. The drawing range is calculated. In the case of this example, since the drawing is a quadrangle, the drawing range in the horizontal direction is "2" which is the drawing position as the starting point and the width is subtracted from the drawing position as the ending point to "6". Is stored in the work memory 51 as a horizontal drawing range. As a result, the numbers of the start point and the end point are continuously stored in the work memory 51, and the stored contents at this time are the data 205 of FIG. 2 (e). The data composed of the start point and the end point in this way is called raster data.

If the black page memory 55 has not been changed to the work memory 51 (S104, NO), color separation of the four colors is performed in step S105, and the writing destination of the image data is selected. Print data 201 is b
Blue specifies blue, and when blue is separated into four colors, it becomes cyan and magenta. Even if the three colors are separated in step S106, the same result is obtained in this case. Then, the cyan page memory 52 and the magenta page memory 53 are selected as the write destination of the image image data. Then, the raster data in the work memory 51 is read by the loop of steps S107 and S108,
Step S108 is executed for each of the three points from "2" to "4" on the ordinate, which is the drawing range in the vertical direction,
In the cyan page memory 52 and the magenta page memory 53, "1" is stored in the bits corresponding to the raster data start point "2" to the end point "6".
“0” is set in the yellow page memory 54 and the black page memory. As a result, image data such as bitmap data 203 (FIG. 2C) is generated in the cyan page memory 52 and the magenta page memory 53. When the image data is generated and the print data expansion process (S5) ends as described above, the data expansion program 61 ends, and the CPU 2 receives the next data from the interface 3 (S1 in FIG. 3).

Returning to FIG. 3 and continuing the explanation, if the received data is the print start command (S2, YES),
The CPU 2 sends the image image data stored in the page memory to the print engine 4 and shifts to print processing.
When the print start command is received, it is first checked whether the black page memory 55 has been changed to the work memory 51 (S12). If the black page memory 55 is not used as the work memory 51 (S12.N
O), cyan page memory 52 for cyan, magenta page memory 53 for magenta, yellow page memory 54 for yellow, black page memory 5 for black.
As in 5, the image image data stored in the page memory corresponding to each ink is sent to the print head of the print engine 4 to perform high-quality printing using four color inks (S6).

When the black page memory 55 is used as the work memory 51 (S12.YE
S) Check whether high-speed printing is designated by the print command (S13), and if high-speed printing is designated (S13)
13 / YES), the image image data is read from the cyan page memory 52, the magenta page memory 53, and the yellow page memory 54, and the data is read by the print engine 4
To the print head, and printing is performed only with the three color inks of cyan, magenta, and yellow (S15). In this case, black is a color mixture of three color inks of cyan, magenta, and yellow, and thus has a slightly brownish color due to the color characteristics of the ink, but the image image data is read directly from the page memory and printed. Therefore, it is possible to perform high-speed printing, as compared with the case of performing page data separation described later.

When high-speed printing is not designated (S13
・ NO), CPU2 is page data separation program 65
Is started to separate the black image image data from the image image data of the cyan page memory 52, the magenta page memory 53, and the yellow page memory 54 (S14). The page data separation program 65 reads the image image data from the cyan page memory 52, the magenta page memory 53, and the yellow page memory 54, calculates the logical product (AND), and sets the result as the black image image data. For yellow and yellow image image data, a logical product (AND) of the image image data read from the page memory and the negative (NOT) of the black image image data is taken, and the AND is performed. To do. Then, the separated image data for four colors is sent to the print head of the print engine 4, and
High-quality printing using color inks is performed (S6). In this case, the portion where the three colors of cyan, magenta, and yellow overlap is replaced with black,
Although it takes some time to separate the black image image data as compared with the case of the three colors described above, black is not browned and printing can be performed with good quality.

Thus, according to this embodiment, the work memory 51 is used when the image data is expanded into the page memory.
When the memory capacity of the black page memory 5 becomes insufficient, the black data is overlaid on the cyan, magenta, and yellow page memories 52, 53, 54, respectively.
Since 5 is released and this is changed to the work memory 51,
For example, 1M for print data for A4 size paper
The byte can be used as the work memory 51. Then, when high-speed printing is performed in the case where the memory is changed as described above, a point having data for each of cyan, magenta, and yellow is printed as black. It should be noted that the present invention is not limited to the above-described embodiments, and various applications are possible. For example, in the present embodiment, the printing mode is switched by checking whether or not there is a command for performing high-speed printing, but it is arbitrary whether or not to adopt this switching process. In addition to the inkjet engine, the print engine 4 uses a toner jet method,
A thermal transfer method, a thermal sublimation method, or the like can be adopted.

[0023]

As is apparent from the above description, according to the color printing apparatus of the first aspect of the present invention, when the work data storage means has enough room for expanding the print data, cyan, magenta, Image data storage means is provided for each color of yellow and black, and image image data is written to that and sent to each of the four color print heads for printing, so high-speed printing with high-quality colors is possible. If the work data storage means is insufficient to expand the print data, the black image data is stored by combining the black image data with the cyan, magenta, and yellow image data. Change the means to work data storage means, cyan,
Since only the image data storage means for three colors of magenta and yellow are used and the image image data of cyan, magenta and yellow are sent to the print heads of three colors for printing, complicated printing is possible even with a small memory amount. Data can be printed, and the cost can be reduced by reducing the memory amount of the work data storage means. According to the color printing apparatus of the second aspect of the present invention, when the black image data storage means is changed to the work data storage means, cyan, magenta, and yellow image image data are changed to black image images. By separating the data and sending each image image data to each print head of four colors, it is possible to print with high quality colors. According to the color printing apparatus of the third aspect of the invention, when the black image data storage means is changed to the work data storage means and high speed printing is performed, black is combined. When cyan, magenta, and yellow image image data are read and printed in three colors, and high-speed printing is not performed, black image image data is separated and printed in four colors, so high-speed printing is required. It is possible to obtain a desired print result by properly using it depending on the case where high quality is required and the case where high quality is required.

[Brief description of drawings]

FIG. 1 is a block diagram of a color printing apparatus according to an exemplary embodiment of the present invention.

FIG. 2 is a diagram showing an example of print data received by a color printing apparatus according to an embodiment of the present invention.

FIG. 3 is a flowchart of the operation of the color printing apparatus according to the embodiment of the present invention.

FIG. 4 is a flowchart of a print data expansion process according to an embodiment of the present invention.

[Explanation of symbols]

 2 CPU 51 Work memory 52 Cyan page memory 53 Magenta page memory 54 Yellow page memory 55 Black page memory 61 Data expansion program 62 Work memory shortage judgment program 63 Page data synthesis program 64 Work memory change program 65 Page data separation program

Claims (3)

[Claims] 1. A color printing apparatus which develops print data consisting of character codes and the like into image image data and performs color printing of the image image data with four colors of cyan, magenta, yellow, and black from the print data. Data expansion means for expanding the image data, work data storage means for the data expansion means to store data necessary for the expansion operation of the print data, cyan, magenta expanded by the data expansion means,
An image data storage unit for storing each image data of yellow and black, a memory shortage determination unit for determining a shortage of the work data storage unit, and a memory shortage determination unit for determining a memory shortage An image data synthesizing unit for synthesizing the black image image data stored in the image data storing unit with each of the cyan, magenta, and yellow image image data and storing the image data in the image data storing unit; A color printing apparatus comprising: a memory changing unit that changes the data storing unit to the work data storing unit. 2. An image data separating means for separating the black image image data from each of the cyan, magenta, and yellow image image data combined with the black image image data stored in the image data storage means. The color printing apparatus according to claim 1, further comprising: 3. When the black image data storage means is changed to a work data storage means and high-speed printing is performed, each image of cyan, magenta, and yellow in which black image image data is combined When the image data is read out and printed in three colors and high-speed printing is not performed, the image data separating means separates the black image image data and prints in four colors. The color printing apparatus according to claim 2.