JPH0449067A - Printing apparatus - Google Patents

Abstract

PURPOSE:To free the central processing unit of an apparatus from inking processing by a method wherein the presence of an output dot to a noticeable black component is judged when a recording color component is black and all of the data of all of the chromatic color components read by a reading means are ones showing the presence of the output dot and a signal showing this state is outputted to a recording means. CONSTITUTION:The image based on the data inputted to a CPU 100 from a data input part 103 is successively developed on the bit map memory corresponding to the color code contained in said data. When the image corresponding to one page is developed, the CPU 100 only outputs a video signal at every color component to a data output part 105 without executing inking processing to carry out the same printing as that carried out when inking processing is actually executed.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a printing device, and more particularly, to a printing device that prints a color visible image on a recording medium by superimposing images of each color component.

[Conventional technology]

Typically, this type of device has bit image memories for four colors: Y (yellow), 1M (magenta), C (cyan), and K (black). Character information (character pattern) sent from a host computer or the like is expanded into a corresponding bitmap memory based on the color code sent in the same way. In this way, multicolor recording is possible by combining each color component. By the way, in this device, if output dots (dots in the ON state) exist in the Y, M, and C bit map memories, the dots in the Y, M, and C bit map memories are turned off. , and performs a so-called inking process in which the corresponding dots in the bit map memory of K are turned on.

[Problem to be solved by the invention]

However, inking one page at a time reduces the processing speed of the entire device, so it is unavoidable to ink one page at a time. Even more so today, when it is so necessary. The present invention has been made in view of such prior art, and it is an object of the present invention to provide a printing device that can free the central processing unit of the device from inking processing and improve processing speed.

[Means for Solving the Problems] A printing apparatus of the present invention that solves this problem has the configuration shown below. In other words, in a printing device that prints visible color images by superimposing images of each color component on a recording medium, a plurality of memories are used to develop images for each chromatic color component and black, and data is simultaneously output from each of the memories. a reading means for reading out a visible image based on color component data, a recording means for superimposing and recording a visible image based on color component data on a recording medium, and a color component recorded by the recording means is one of chromatic colors, and the color component read by the reading means a first output means for outputting the chromatic component of interest to the recording means as having no output dot data when all the data of all the chromatic color components are data indicating the presence of output dots; and recording by the recording means. When the color component is black and all the data of all chromatic color components read out by the reading means are data indicating that output dots are present, the black component of interest is recorded as having output dots in the recording means. and second output means for outputting the output.

[Effect]

In this configuration of the present invention, data for each color component is read out simultaneously from each memory. If the color that the recording means is trying to record is one of the chromatic colors, and the dot information of all the read chromatic color data is data indicating that there are output dots, then the chromatic color of interest The component is outputted to the recording means as having no output dot data. When the target to be recorded by the recording means is black, and when all the dot information of the chromatic color data read out by the reading means is data indicating the presence of output dots, the black component of interest is The output dots are outputted to the recording means as output dots.

【Example】

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 2 is a diagram showing a schematic configuration of a printing apparatus according to an embodiment. In the figure, 100 is a CPU (central processing unit) that controls the entire device. 102 is the main memory, and the CPU
It consists of a ROM (read only memory) Iota that records ioo control programs, character font patterns, etc., and a RAM (random access memory) 101b that is used as a work area. 102 is Y,
R having bitmap memory for each color component of M, C,
AM, and 103 is a data input unit for inputting data from the host computer. 104 is RAM102
A video interface reads the data of each color component developed in a predetermined procedure, converts it into a video signal and outputs it, and 105 is a data output that prints a visible image on recording paper based on the video signal output from the video interface 104. Department. Incidentally, a case will be described in which a laser beam printer is employed as the data output section in the embodiment. In the above-described configuration, the CPU 100 of the embodiment sequentially develops an image based on information input from the data input unit 103 into a bitmap memory corresponding to a color code included in the information, and one page at a time. When the image for each color component is developed, the CPU 100 does not perform the inking process and sends the video signal for each color component to the data output unit 105.
By simply outputting to , it is possible to print in the same way as when actually inking is performed. FIG. 1 shows the specific configuration of the RAM 102 and video interface 104 of the embodiment. As shown in the figure, the RAM 102 includes bitmap memories 102a (Y) and 102b (M) for four colors. It is composed of 102c (C) and 102d (K). As described above, output image information for each color component is developed in these bitmap memories 102a to 102d. Each arrow indicates a signal or information flow,
The numbers in the middle of these arrows indicate how many bits the information consists of. In the figure, 1 is the address bus of the CPU 100, and the bus excluding the lower 2 bits "AO"A1" is supplied to each bitmap memory 102aA-102d. 4 is the address bus of the bitmap memories 102a, 102b.
, 102c, 102d data 10a, 10b, 1
This is a selector that reads and selects 0c and 10d, and C
Lower address 2 bits of address 1 from PU100
One of the four output lines is selected by "AO" and "A1". 3 is a bit processing unit that performs inking processing, and the bitmap memory 102a
, 102b, 102c, 102d data 10a,
input fob, 10c, and 10d, and input the data corresponding to the color to be converted into the video to the lower 2 bits of address 1 “AO”.
"A1" selects and performs bit processing, and outputs the output 6 to the video signal converter 5. This video signal converter 5 converts the output 6 from the bit processing unit 3 into a video signal 7, Video interface 10
4 is the above-mentioned bit processing unit 3. Selector 4. It is composed of a video signal converter 5. FIG. 3 is a diagram showing an example of the internal circuit configuration of the bit processing unit 3 in the embodiment (however, the processing portion in units of 1 bit is shown). The operation of this circuit will be described below, assuming that image data corresponding to each color has already been developed in each bitmap memory 102a to 102d. Also, when expanding data to each bitmap memory, there is a circuit that activates only one bitmap memory.
It is assumed that the circuit is used to develop data in each memory. However, this does not apply if the data bus 2 has 32 bits. FIG. 3 shows processing in units of 1 bit. Bitmap memories 102a, 102b, 102c, 1
It is assumed that image data of Y, M, and C are respectively developed in 02d. In addition, the selector 20 in the illustration
In this case, when the lower two bits [A+ and Ag3 of address bus 1 are [0 and Oj], data 10a (Y component data) from bitmap memory 102a is selected. Similarly, data 10b (M component data) when [0, l], data 10c (C component data) when [1, Oj],
And when [1, 11, data i. d (K component data) is selected. The output of the selector 20 is supplied to an AND circuit 23.25, and the lower bit [
A+, A0] becomes [0, Oj [0, 17 [1, Oj [1
, 1]. Also, bitmap memory 1
02a=102c (excluding 102d) Output data 10a. 10b and 10c are input to a NAND circuit 21, and the output thereof is input to an AND circuit 26 and an inverter 27. Furthermore, the lower two bits of address 1 [A, A l+1 are input to the NAND circuit 22, and the output thereof is input to the AND circuit 2.
3 and the inverter 24. The output of the inverter 24 is input to an AND circuit 25. The output of the inverter 27 is input to an AND circuit 28, and the output thereof is input to an OR circuit 30. Further, the output of the AND circuit 26 is input to an OR circuit 29. In the circuit configuration described above, image data is developed in each bitmap memory 102a to 102d, and the image data is developed in each color unit, that is, the bitmap memory 102a. When video conversion is performed in the order of 102b, 102c, and 102d, the CPU 100 uses the lower two bits [A, . . .
AO] to [0, O]. Bitmap memory 102
Since data a to 102d are accessed simultaneously, each data is output as data 10a to 10d. Now, the 2nd bit of address bus 1 (A + , A o is [0, 0]
Therefore, the output of the NAND circuit 22 is HIGH (=1
) level. Therefore, the AND circuit 23 is opened and the AND circuit 23 is opened.
Circuit 25 is closed. The selector 20 selects the output data 10a from the bitmap memory 102a and outputs it. Here, since the AND circuit 23 is open,
The AND circuit 23 outputs output data loa. Here, let us consider a case where there is no need to perform cornering. In other words, when the output dots of Y, M, and C do not overlap, in other words, at least one of the data 10a, 10b, and 10'C is at a LOW level (20), in this case,
Since the output of the NAND circuit 21 becomes HIGH, the AND
The circuit 26 will be open and the AND circuit 28 will be closed. At this time, since the AND circuit 25 is also closed, the output of the OR circuit 30 is at a LOW level. Also, AND circuit 2
Since bitmap memory 102a is open, data 10a of bitmap memory 102a becomes output 6 of OR circuit 29 and is converted into a video signal. When performing inking processing, that is, bitmap memory 10
Data 10a from each of 2, 102b and 102c,
Consider the case where both 10b and 10c are at HIGH level. The output of the NADN circuit 21 becomes LOW, and the output of the AND circuit 2
Since the output 6 of the OR circuit 29 is closed and the AND circuit 25 is also closed at this time, the output 6 of the OR circuit 29 becomes LOW level. In other words, the output data 10a (Y
Even if the color component (component) is at a HIGH level, it will be at a LOW level due to the relationship between the other color components M and C and will not be printed.
The same can be said of the outputs 10b and 10c. Next, output data 10 from the bitmap memory 102d
Consider the operation of video signal conversion of d (K=black component data). In this case, the CPU 100 accesses the RAM 102 by setting the lower two bits [A, AOI] of the address bus 1 to [1, 1]. Therefore, the output of the NAND circuit 22 is LOW.
Therefore, the AND circuit 23 is closed and the AND circuit 25 is opened. The selector 20 selects and outputs the data 10d. Let us now consider the case where the output dots of the Y, M, and C components do not overlap at the same position and there is no need for inking, as described above. In this case, the output of the NAND circuit 21 becomes HIGH, so the AND circuit 28 is closed. Also, since the AND circuit 23 is closed at this time, the output of the AND circuit 26 is at a LOW level. Since OR circuit 30 is open, OR circuit 2
9 is the output of the AND circuit 25, that is, data 10.
d will be output. Next, consider a case where inking is required. In this case, the AND circuit 21 becomes LOW level, so A
ND circuit 26 is closed. Also, since the output of the AND circuit 28 is at a HIGH level, the output of the OR circuit 30.29 is at a HIGH level. In other words, bitmap memory 10
Output 6 is H regardless of the content of data lOd from 2d.
It becomes IGH and K (black) is printed. As explained above, according to this embodiment, when the image data of each color component is developed in each bitmap memory, the CPU 100 only needs to read and output the requested color component data from the data output unit 105. , it is possible to obtain the same effects as those obtained by performing cornering processing. In the above-mentioned embodiment, it was explained that the CPU 100 performs the reading operation of the RAM and converts the video, but the DM
Although it is stated that it is possible to read the RAM using A, and that the four colors are video converted and output sequentially, it is also possible to video convert the four colors at the same time. In other words, data selection by the selector 20 is no longer necessary, but a video converter is required for each color.

【Effect of the invention】

As described above, according to the present invention, it is possible to free a central processing unit such as a CPU from inking processing and improve processing speed.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the circuit configuration of the RAM and video ink face in the embodiment, FIG. 2 is a block diagram of the printing device of the embodiment, and FIG. 3 is a diagram showing the circuit configuration of the bit processing unit in FIG. 1. It is a diagram. In the figure, 1...address bus, 2...data bus, 3
...Bit processing unit, 4...Selector, lOO・
...CPU, 101...Main memory, 102...RA
M. 102a to 102d...Bitmap memory, 103
. . . data input section, 104 . . . video interface, 105 . . . data output section.

Claims (1)

[Scope of Claims] A printing device that prints visible color images by superimposing images of each color component on a recording medium, comprising: a plurality of memories for developing images of each chromatic color component and black images; a reading means for simultaneously reading data from each; a recording means for superimposing and recording a visible image based on color component data on a recording medium; and a color component recorded by the recording means is one of chromatic colors,
When all the data of all chromatic color components read out by the readout means are data indicating that output dots are present, a first output is outputted to the recording means as no output dot data for the chromatic color component of interest. means, when the color component recorded by the recording means is black and all the data of all chromatic color components read by the reading means are data indicating that there are output dots, for the black component of interest; A printing apparatus comprising: a second output means for outputting to the recording means as an output dot.