JPH0262263A - Image formation device - Google Patents

Abstract

PURPOSE:To enable visual checking of an internal set state of a printer by providing a plurality of print modes, a plurality of color processing functions and a means to output a test print on the basis of the set state of the print mode and the color processing function. CONSTITUTION:Print data and a command are inputted to PIO 1 through centronics I/F. CPU 8 reads them and analyzes the command, storing necessary print data in RAM 10. The following inputs are supported as the print data: 1) a CMY input (each color has 2/16/256 gradations), 2) an RGB input (each color has 2/16/256 gradations) and 3) a pallet input (8 colors, 16/256 colors). Various print data are converted into values 0 to 255 of density of C, M and Y to be printed, in this way. There are various commands in relation to an image processing. Setting is made at some default value immediately after a power source is turned ON or immediately after resetting, and it can be varied freely by a user by sending a command.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an image forming apparatus, for example, a full color printer such as an inkjet printer.

[Conventional technology]

In recent years, full-color printers have been developed that have image processing circuits for masking, undercolor removal, complementary color conversion, etc., and with such full-color printers, beautiful full-color prints can be obtained by simply sending simple commands from a personal computer. It became like that.

[Problem to be solved by the invention]

This type of printer is equipped with a wide range of image processing functions in order to reduce the image processing load on the host computer side as much as possible. Therefore, when a large number of people are performing various types of printing, it is easy to forget what the current internal state of the printer is, and there is a possibility that unexpected printouts may be obtained.

Of course, in order to avoid such troubles, the printer has a switch that resets it to its initial state, but if it is in the state that you have set, it will save you the trouble of resetting and resetting it.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide an image forming apparatus capable of test printing a wide variety of internal states.

[Means for Solving the Problems] The present invention is characterized by comprising a plurality of print modes, a plurality of color processing functions, and a means for outputting a test print based on the setting states of the print modes and color processing functions. do.

[Effect]

According to the present invention, the internal state of the printer can be visually checked by making a test print of the internal setting state of the printer.

(Example) The present invention will be described in detail below with reference to the drawings.

FIG. 1 shows an internal block diagram of a full-color printer according to an embodiment of the present invention.

Print data and commands from the personal computer are input through one Centronics I/F. This is 8 CP
u analyzes the read command, and the necessary print data is stored in 10 RAMs. The ROM 9 stores programs and various initial value parameters.

Printer operation setting switch (online SW).

Line feed SW, form feed SW, etc.) and operation status display LEDs are outputted via 12 PIOs. PIO 13 is the line feed motor (L) of the printer.
This is a boat to which the F motor), carriage motor (CR motor), and various sensors are connected. Next, the flow of print data will be explained.

The following types of print data are supported.

1) CMY input (2/16/256 gradations for each color) 2) 1
68 manual input (2715/256 gradations for each color) 3) Palette input (8 colors, 16 colors/256 colors) Regardless of the manual input, the printer can process the three primary colors of C (cyan), 1M (magenta), and Y ( yellow). The method of conversion is shown in FIG. First, in the case of 1) CI and IY manual operation, the CM shown in 3 in Figure 1 is directly processed without going through any conversion table except for adjusting the data width to 8 bits.
It is input to each latch of Y. A method for aligning the width to 8 bits can be realized by a simple calculation shown in the following equation.

In the case of 21 RGB manually, after adjusting the data width to 8 bits, it is necessary to convert to RC, GM, and B→Y respectively. This is called complementary color conversion, and various conversion methods have been devised. For example, there is a simple method shown in the following equation. In any case, R-C.

G-M and B-Y can be uniquely determined, and conversion can be done quickly by referring to a table. Therefore, the conversion table is called a gamma table, and this is shown in Figure 1. Indicated by 2. This table 2 can actually be implemented in RAM and can be shared with 10 I'lAMs.

Next, in the case of manual palletization, the pallet number and the actual expression color are determined by the sending computer or frame memory, and the pallet number is usually around 16 to 256.
The number of colors a printer can express is 260,000 colors (one unit is much larger, so sending a palette number to the printer is much more efficient than sending an expression color number. It is necessary to provide the contents of the bullet data held on the host side to the printer side.This WSB area is a pallet conversion table shown by 11 in Figure 1, and the pallet data created manually The numbers are converted to R, G, and B by this palette conversion table, and then converted to C, G, and B via the gamma table 2 described earlier.
Converted to M and Y.

In this way, one layer of print data is converted into C, M, and Y density values (normalized to 0 to 255) to be printed. These C, M, and Y and the C, M, and Y of the ink are not equal because they are asymmetric color components of the ink, and in order to remove these asymmetric color components, a masking circuit shown in 4 in Figure 1 is used. There is.

The masking circuit 4 typically needs to perform calculations as shown in the following equation, but in practice, in order to increase the speed (masking), it is realized by table conversion using a ROM. Furthermore, gradation expression of black part 1
To improve color reproduction, black ink is used separately in printing. This is called undercolor removal, and this printer also uses this masking ROM to generate black.

In this way, in the masking circuit 4, C'', M', Y
'C''1M with masking and undercolor removed
Ink density data for the four colors "Y" and "Y" are output.

For this four-color density data, actually three ink heads with different densities are used for cyan and magenta, so choose which head to use.

Dither processing for expressing the gradation of the highlight portion is realized by 5 selection ROMs (each selection of cyan, magenta, yellow and black + 10M). Select like this 11
0M5 determines what voltage to drive the 8 color ink heads in order to reproduce one point of color, and the head drive pulse is generated by the head driver 6 using that data manually. 7 heads.

A CR motor that controls the main scanning direction of the head (not shown) and an LF motor that controls paper feed are connected via 13 PIOs, and the CpH8 is controlled as a whole based on timing signals from various sensors. Process.

Now, in such a full color printer, there are various commands related to image processing as shown below.

■ Changing the palette table ■ Changing the gamma table ■ - Changing the number of bits per pixel ■ Selecting from three print modes: RGB/CMY/palette ■ There are enlargement ratios, etc., and the default value is set immediately after turning on the power or immediately after resetting. It is set as such, but it can be changed freely by the user by sending the above command.

On the nut layer side, CI'lJ8 selects the selection ROM5. Controls the head driver 6.

There is also a method of installing a dedicated switch as a panel SW,
Here, test printing is started by pressing multiple keys at the same time. For example, multiple presses of the online SW and the line feed or form feed SW. Of course, this can also be done by sending a dedicated command.

A concrete sample of the print is shown in Figure 3.

According to this test print, the internal state of the printer described above was devised to be visually expressed, and the actual print of the colors registered in the palette data, gamma curve display, print mode, bit size, X direction, The magnification ratio in the Y direction, etc. are printed.

Figure 3 shows an example of a test print that outputs color batches of a color palette, but when the human power is in R, G, B input mode instead of palette mode, 256 color patches can be printed in R.
, G, and B may be considered, but it is more useful to create a color batch in the mode in which it actually operates. It is also conceivable to write numerical data (0 to 255) of R, G, B or C, M, Y together with the color patch.

It goes without saying that the present invention can also be used in inkjet printers other than those described above, such as thermal transfer or thermal sublimation printers.

Furthermore, even if the image processing functions other than those described above are increased or decreased, this can be handled by correspondingly increasing or decreasing the contents of the self-test.

As mentioned above, for example, in a full-color printer that can reproduce colors using palettes, you can check the correspondence between the palette number and the actual print color just by performing a test print, and you can avoid unnecessary actual printing. In addition, if you are not using a palette manually, you can check the expressed colors as color patches after masking and gamma curves are applied.

(Effect of the invention) As explained above, according to the present invention, can be visually confirmed.

internal state

[Brief explanation of the drawing]

Fig. 1 is a block diagram of an embodiment of the present invention, Fig. 2 is a conversion flow of various print data, and Fig. 3 is a diagram showing an example of test printing.

Claims (1)

[Claims] 1) Image formation comprising: a plurality of print modes; a plurality of color processing functions; and means for outputting a test print based on the setting states of the print modes and color processing functions. Device.