JP3427975B2 - Printer control circuit, printer and print system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer control technique for high speed printing.

[0002]

2. Description of the Related Art In a print system, original image data in a host computer is host-side color system data, typically RGB data, which does not necessarily match printer-side color system data (typically CMYK data). is there. This RGB data is for Windows 9 of Microsoft
The format is different for each OS such as 8 and Macintosh of Apple Computer, in other words, the format of RGB data depends on each OS.

[0003]

A process for printing out original image data in a host computer,
That is, the color conversion processing for converting RGB data into CMYK data and the halftoning processing for binarizing the CMYK data are performed by the printer driver in the host computer.
Alternatively, it is performed by the printer (strictly speaking, the imaging software in the printer).

When processes such as color conversion and halftoning are performed on the printer side, the printer driver of the host computer receives original image data, that is, RGB data from the OS of the host computer and transfers it to the printer. Since the printer driver does not perform color conversion or halftoning processing, the load on the CPU of the host computer is correspondingly light. However, the printer driver
Since the RGB data has a format that depends on the OS, the format must be converted into a format that the receiving printer can understand and perform the above conversion processing.

This RGB data format conversion is
This causes a considerable load on the CPU of the host computer, and as a result, there is a problem that the opening of the host device is delayed and the printing speed decreases.

Therefore, it is an object of the present invention that the host device is R
In a print system for transferring GB data to a printer without color conversion or halftoning, it is to reduce the processing load on the host device and increase the printing speed.

[0007]

According to the present invention, a printer control circuit is provided between a host device and a printer. This printer control circuit may be built in the host device, built in the printer, or external to both. The printer control circuit includes a receiving unit, a format converting unit, and an image data transferring unit. The receiving means is configured to
The original image raster data whose array is dependent on the OS in the host device and the byte array of the original image raster data are shown.
And a byte order parameter from the host device.
The format conversion means determines the byte order parameter received.
The byte array of the original image raster data based on the
Are sorted into a fixed common byte array . The image data transfer means converts the image data output from the format conversion means into image data in a format that can be processed by the printer and transfers the image data to the printer.

[0008] According to the present invention, a printer control circuit, Hara
The above byte array of image raster data is converted into a common
Since the process of rearranging to the right array is performed , the host device
It is not necessary to perform the processing, thus reducing the load on the CPU of the host device and enabling high-speed printing.

In the preferred embodiment, the printer control circuit is a pure hardware circuit. As a result, the printer control circuit becomes an ASIC (Application Specified IC).
It can be made cheaper than a conventional high-speed printing system equipped with a high-speed CPU.

[0010]

In a preferred embodiment, the receiving means is the original image.
Number of effective bytes in 1 pixel data in raster data
The effective byte number parameter that indicates is also received from the host device,
For the format conversion means, refer to the effective byte count parameter.
As a result, the number of effective bytes of the original image raster data is less than the number of bytes of 1 pixel data composed of the common byte array, and an empty byte is generated in the 1 pixel data composed of the common byte array. If it ends up ,
Create null data to fill the empty bytes
Perform mask processing to fill the empty bytes with data
It

For example, when 1 pixel data composed of a common byte array is 4 bytes, whereas 1 pixel data of the original image raster data has 3 effective bytes , 1 byte space is left. A bite will occur. Therefore, the format conversion means automatically creates null data for the empty byte of 1 byte and performs mask processing with the null data. Creating null data is done in bytes
Since it can be performed in parallel with the rearrangement processing of the array, it is possible to prevent deterioration of the printing speed.

In a preferred embodiment, the printer control circuit further includes a circuit for performing color conversion processing and halftoning processing on the image data output from the format conversion means, and after performing the color conversion processing and halftoning processing. Transfer the image data of to the printer.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the overall configuration of a printing system according to an embodiment of the present invention.

In the printing system shown in FIG. 1, the original image data (that is, RGB
The intermediate hardware 4 provided between the host computer 1 and the printer 3 performs the process of converting (data) to final CMYK data. That is, the intermediate hardware 4 is pure hardware made of ASIC (Application Specified IC) or the like, and uses the CMYK system (or CMY system) of the RGB raster data sent from the host computer 1 by using a lookup table or the like. ) Of the CMYK raster data that has been converted into color data, and pixel values of 256 gradations of each color of the color-converted CMYK raster data are not hit or not hit by dots of each color of CMYK by using a method such as error diffusion or dithering. “Halftoning” or the like for converting into a two-stage pixel value indicating that is performed. Further, when the printer 3 is, for example, an inkjet printer or an impact wire dot printer, in order to improve the image quality, so-called “interlaced” printing or “overprinting” in which dots are printed in an order different from the arrangement order of pixel positions is used. It also performs processing for performing "wrap" printing.

The original image data (RGB) received from the host computer 1 by the intermediate hardware 4 for performing the above-mentioned respective processes.
Data) is the image data that has been expanded into a bitmap,
In other words, it is raster image data and has a format depending on the OS 7 of the host computer 1. The intermediate hardware 4 includes a format conversion circuit 5 for converting the RGB raster image data having a format dependent on the OS 7 from the host computer into a predetermined common format, and the color conversion and the above-described color conversion for the common format RGB data. It has a color conversion / halftoning circuit 6 that performs halftoning processing. As described above, the format conversion circuit 5 and the color conversion / halftoning circuit 6 are, for example, ASI.
A hardware logic circuit such as C, which is not a computer in which software is executed by a CPU, enables high-speed processing.

In the host computer 1, the printer driver 11 receives the image data 9 created by the application software from the OS 7, and if it is represented by a graphic function or a character code, "rasterize" it, that is, bit it. The map is expanded to create raster image data 10. This raster image data 10
The format relating to the color system and the number of gradations is typically an RGB full color format, that is, an 8-bit word capable of expressing 256 gradations for each color component of one pixel in the RGB color system.
Other formats, such as RGB binary, monochrome 256 gradation, monochrome binary, etc., are also possible. In the following description, the raster image data 10 is RGB full color data, and will be referred to as RGB original image data 10 hereinafter. This R
The data format of the GB original image data 10 is OS7.
Depends on the type. For example, as shown below.

(1) Format of "first OS": <
R, G, B><R, G, B> ... Here, <> means data for one pixel. In this format, data for one pixel is composed of 3 bytes arranged in the order of R, G, and B.

(2) Format of "second OS": <
R, G, B, x><R, G, B, x> .... That is, data for one pixel is composed of 4 bytes arranged in the order of R, G, B, and x. Here, “x” is a byte indicating the attribute of the image.

(3) Format of "third OS": <
B, G, R><B, G, R> ... That is, the data for one pixel is composed of 3 bytes arranged in the order of B, G, and R.

(4) "Fourth OS" format: <
x, R, G, B><x, R, G, B> ... That is, data for one pixel is composed of 4 bytes arranged in the order of x, R, G, and B.

The printer driver 11 converts the RGB original image data 10 having a format dependent on the OS 7 into an intermediate command 13 having a predetermined command format that the intermediate hardware 4 can understand, and transfers it via the OS 7. Send to intermediate hardware 4.

The intermediate hardware 4 is connected between the host computer 1 and the printer 3. The format conversion circuit 5 of the intermediate hardware 4 receives the intermediate command 13 from the host computer 1, refers to the format parameter included in the intermediate command 13, and follows the RGB parameter accordingly.
The OS7-dependent data format of the original image data 10 is a common format (for example, <x, R, G, B><
x, R, G, B> ...) RGB data 53 and sends it to the color conversion / halftoning circuit 6. Color conversion
The half-toning circuit 6 has a common format R
The GB data 53 is color-converted into CMYK data, which is further half-toned to be converted into CMYK binary data, which is sent to the printer 3 as a printer command 55 that the printer 3 can understand.

A more specific description will be given below.

The printer driver 11 uses the RGB original image data 10 to create an intermediate command 13 having the structure shown in FIG.

FIG. 2 shows the structure of the intermediate command 13 output by the printer driver 11.

As shown in FIG. 2, the intermediate command 13 is
It is composed of a command name field 15, a format parameter field 17, and an original image data field 19 in which the RGB original image data 10 is set.

In the command name field 15, a command name indicating the intermediate command 13, for example, <xfe
rJ> is set.

In the format parameter field 17, a format parameter (hereinafter referred to as f parameter) indicating the format of the RGB original image data 10 set in the RGB original image data field 19 is set. The f parameter is, for example, an 8-bit word as shown in FIG. 3, and the “effective byte number” parameter 21 is set in the lower 2 bits and the “byte order” parameter 23 is set in the next lower 5 bits (the remaining 1 bit is
(Eg empty data). "Number of valid bytes" parameter 21
Indicates how many bytes of effective data for one pixel in the RGB original image data 10 is composed of
If "11", 4 bytes are valid (that is, one pixel consists of 4 bytes), and if "10", 3 bytes are valid (that is, 1 pixel).
Pixel is composed of 3 bytes). The “byte order” parameter 23 indicates the arrangement order of the R, G, and B components in the number of effective bytes of the RGB original image data 10. “0000” is “B, G, R”, and “01110” is “R, G. G, B, x ”or“ R, G, B ”,“ 1011
If it is “1”, it means that they are lined up with “x, R, G, B”.
Specifically, the parameters are set as follows for the above-described first to fourth OSs.

(1) “First OS” format: <R, G, B>
<R, G, B> ... → “10” “01110” (2) “Second OS” format: <R, G, B,
x><R, G, B, x> ... "11""01110" (3) "3rd OS" format: <B, G, R>
<B, G, R> ... “10” “0000” (4) “4th OS” format: <x, R, G,
B><x, R, G, B> ... → “11” “10111”.

FIG. 4 shows the configuration of the intermediate hardware 4.

The format conversion circuit 5 of the intermediate hardware 4 includes a command interpretation circuit 25, an input register 27, a position counter 29, a write byte position decoder 31, a byte write circuit 33, a mask data generation circuit 35, and a byte position mask processing circuit 37. , Output register 39.
The intermediate command 13 from the printer driver 11 is first received by the command interpretation circuit 25.

When the command interpreting circuit 25 recognizes from the above command name that the command is the intermediate command 13, the "effective byte number" parameter 21 and the "byte order" parameter 23 of the f parameter 17 included in the command 13 are recognized.
To the input register 27, and the RGB original image data 10
Is transmitted to the byte writing circuit 33. The input register 27 has at least a storage area 41 for the "effective byte count" parameter 21 and a "byte order" parameter 23.
Storage area 43 of The RGB original image data 10 is transferred to the OS 7 by the byte writing circuit 33.
The data is output to the corresponding byte plane out of 4 bytes according to the arrangement order of each color data in the dependent format. For example, if the RGB original image data 10 is composed of the above-mentioned "first OS" -dependent format <R, G, B>, it is input in the order of "R"->"G"->"B". , "Second OS" -dependent format <
x, R, G, B>, then “x” → “R”
→ "G" → "B" are input in this order.

The byte position counter 29 counts each color data read by the byte writing circuit 33, and resets the counted number to the same value as the number of valid bytes recorded in the input register 27. To go. For example, if the number of valid bytes is 4 bytes,
It is reset every four times, such as “0, 1, 2, 3, (reset) 0, 1, 2, 3, (reset) 0, ...”. If the number of valid bytes is 3 bytes, "0,
1, 2, (reset) 0, 1, 2, (reset) 0,
"..." is reset every time it counts three times. The byte position counter 29 counts in this way, and each time the above-mentioned respective color data are read, the count result (that is, the byte position of each color data in the RGB original image data 10) 45 corresponding thereto is written into the write byte position decoder 31. To notify.

The write byte position decoder 31 receives the count result 45 from the byte position counter 29 and the "byte order" stored in the input register 27.
Refer to the byte order shown in the parameter 23. Then, based on that, the above-mentioned common format 4
For the byte data, it is determined at which byte position the read color data is to be written, and the determined write byte position 47 is instructed to the byte write circuit 33.

The byte write circuit 33 is provided in the input register 2
Each color data of the RGB original image data 10 stored in 7 is read (that is, read one byte at a time), and each is written in a predetermined byte position of the common format data according to the instruction of the write byte position decoder 31. This will be specifically described with reference to FIG.
Here, the common format is <x, R, G, B>
Suppose

RG coming through the command interpretation circuit 35
If the format of the B original image data 10 depends on, for example, the “first OS” (that is, <R,
G, B><R, G, B> ...), as shown in FIG.
Byte writing circuit 33 in the order of “R” → “G” → “B”
Comes in. The byte write circuit 33 follows the instruction of the write byte position decoder 31 and outputs the first “R”.
Is written in the second byte of the register 48, the second "G" is written in the third byte, and the third "B" is written in the fourth byte. If it depends on the above "second OS",
As shown in (B), each data is read in the order of “R” → “G” → “B” → “x”, and the first “R” is read at the second byte according to the above instruction. The "G" is written in the third byte, the third "B" is written in the fourth byte, and the fourth "x" is written in the first byte. When it depends on the above “third OS”, as shown in FIG. 5C, “B” →
Read each data in the order of “G” → “R”, and according to the above instruction, read the first “B” at the 4th byte, the second “G” at the 3rd byte and the third “R”. Write each in the second byte. When it depends on the “fourth OS”, as shown in FIG. 5D, “x” → “R” → “G”
→ Read each data in the order of "B", and follow the above instruction, the first "x" is the first byte, the second "R" is the second byte, and the third "G" is the third byte. The 4th "B" is written in the 4th byte.

The byte writing circuit 33 reads out the effective data for one pixel in the RGB original image data 10 respectively, and when the byte writing is completed, the written data 49 is passed to the byte position mask processing circuit 37.

In writing the effective data (each color data) for one pixel described in FIG. 5, if the effective data is 3 bytes (that is, the “effective byte number” is 3 bytes), 1 byte of the register 48 Nothing is written to the eyes, so it is the value originally written there. Therefore, the mask data generation circuit 35 and the byte position mask processing circuit 37 perform a mask process for the first byte in order to make the first byte null data.

That is, the mask data generation circuit 35
"Number of valid bytes" parameter 21 from input register 27
And the "byte order" parameter 23 are read out, and with reference to them, 4-byte mask data 51 corresponding to the number of bytes of the post-writing data 49 is generated. That is, when the "effective byte count" is 3 bytes, a mask in which all the bits of the 1st byte are 0 and all the bits of the other 3 bytes are 1 in order to make the 1st byte of 4 bytes null data. Data 51 is generated. "Effective byte count" is 4
In the case of a byte, the mask data 51 in which all the bits of the 4 bytes are 1 is generated so that no masking is performed on any byte. The mask data generation circuit 35 passes the generated mask data 51 to the byte position mask processing circuit 37.

The byte position mask processing circuit 33 receives the post-writing data 49 from the byte writing circuit 33 and the mask data 51 from the mask data generating circuit 35, respectively, and outputs the post-writing data 49 and the mask data 51 to the AN.
D operation is performed, and the AND operation result 53 is output to the output register 39.
Write to. Specifically, as described above, when the “effective byte number” is 3 bytes, the mask data 51 from the mask data generation circuit 35 has “0, 0, 0, "..." and the other 3 bytes are set to "1, 1, 1, ...". Therefore, by performing an AND operation on the post-writing data 49 and the mask data 51, the operation result data 53 is The first byte “x” is null data of “0, 0, 0, ...”, and the other 3 bytes “R, G, B” are “R, G, B” of the post-writing data 49.
G, B ”. When the “effective byte count” is 4 bytes, the masked data 53 is exactly the same as the written data 49. The byte position mask processing circuit 37 writes the masked RGB data 53 into a predetermined address of the output register 39.

The above-mentioned RGB written in the output register 39
The data 53 is taken into the color conversion / halftoning circuit 6.

According to such an embodiment, the host computer 1 (printer driver 11) does not need to perform format conversion of the RGB original image data 10 at all,
This format conversion is performed by a dedicated hardware circuit (that is, the format conversion circuit 5 of the intermediate hardware 4).
Will do. The host computer 1 only needs to specify the format type of the RGB original image data 10 to the intermediate hardware 4. Therefore, C of the host computer 1
The load on the PU is considerably reduced as compared with the prior art, and as a result, high-speed printing is possible without delaying the opening of the host device. Also, the host computer 1
Can arbitrarily set the "byte order" parameter, so even if the OS 7 is of any type, or if the format of the image data 10 required by the OS 7 changes, " It is possible to deal with this by changing the setting of "byte order". Further, the host computer 1 can set the "effective byte number" parameter according to the color system of the original image data 10 and the format relating to the number of gradations, which also contributes to high-speed printing as described below. To do.

For example, when the color system of the original image data 10 is a monochrome tone, the RG is sent from the host computer 1.
Since only the "G" data of the B data is continuously transmitted, the host computer 1 sets the "effective byte number" parameter 21 to "1 byte effective". This allows
Each time the format conversion circuit 5 receives 1-byte “G” data, it writes it in a designated byte position and, in parallel, automatically generates mask data including 3-byte null data that becomes an empty byte. Then, mask processing is performed. Thus, since the null data is generated in parallel with the writing of the color data, it is possible to print at high speed without degrading the printing speed.

Further, since the intermediate hardware 4 can be created by an ASIC or the like, it is cheaper than the conventional high speed printing system equipped with a high speed CPU.

The arrangement form of the intermediate hardware 4 has three variations as shown in FIG.
That is, as shown in block 10 in FIG. 6, a system built in the host computer 31 as shown in block 10, a system built in the printer 9 as shown in block 30, and externally attached to the host computer 31 and printer 9 as shown in block 20. It is a method. In the host built-in type, the format conversion circuit 5 is provided in the form of an option board for the host computer, is connected to the internal bus of the host computer 31, and is connected to the printer 9 by a parallel interface cable (or a communication network) or the like. You can connect with. This has the advantage of being compatible with multiple printers. On the other hand, in the printer built-in type, the format conversion circuit 5 is provided in the form of a printer option board and is connected to the internal bus of the printer 9,
The host computer 31 can be connected to, for example, a parallel interface cable (or communication network). This has the advantage of being compatible with multiple hosts. In addition, in the external type, the format conversion circuit 5
Can be connected to both the host computer 31 and the printer 9 with, for example, a parallel interface cable (or communication network).

Some preferred embodiments of the present invention have been described above, but these are merely examples for explaining the present invention, and the scope of the present invention is not limited to these examples. . The present invention can be implemented in various other forms. For example, a part of the function of the intermediate hardware 4 may be implemented by software by the CPU for the intermediate hardware 4.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of a print system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing the configuration of an intermediate command 13.

FIG. 3 is a block diagram showing the configuration of a format parameter field 17.

FIG. 4 is a block diagram showing a configuration of intermediate hardware 4.

FIG. 5 is a diagram for explaining a byte writing method of each color data of the RGB original image data 10 depending on the first to fourth OSs.

FIG. 6 is a diagram showing a variation of the arrangement of the original image data format conversion circuit 5.

[Explanation of symbols]

1 Host computer 3 printers 4 Intermediate hardware 5 Original image data format conversion circuit 6-color conversion / half-toning circuit 7 OS 11 Printer driver 25 Command interpretation circuit 27 Input register 29-byte position counter 31 write byte position decoder 33-byte writing circuit 35 Mask Data Generation Circuit 37-byte position mask processing circuit 39 Output register

Claims (10)

(57) [Claims] 1. A printer control circuit connected between a host device and a printer, wherein a byte array forming one pixel data is O in the host device.
Receiving means for receiving, from the host device, original image raster data that depends on S, and a byte order parameter indicating the byte array of the original image raster data; and the original means based on the byte order parameter. A format conversion unit that rearranges the byte array of the image raster data into a fixed common byte array, and the image data output from the format conversion unit is transferred to the printer as image data in a format that can be processed by the printer. Image data transfer means , wherein the receiving means is a unit of one image in the original image raster data.
Effective byte number parameter indicating the effective byte number in the raw data
Data is also received from the host device, and the format conversion means sets the valid byte number parameter.
Data, and as a result, before the original image raster data
The effective number of bytes consists of the common byte array.
Less than the number of bytes of 1 pixel data, the common byte
An empty byte is generated in 1 pixel data composed of an array.
If it does, to fill the empty bytes
The null data of the
A printer control circuit that executes mask processing for filling the 2. A printer control circuit connected between a host device and a printer, wherein a byte array forming one pixel data is O in the host device.
Receiving means for receiving, from the host device, original image raster data that depends on S, and a byte order parameter indicating the byte array of the original image raster data; and the original means based on the byte order parameter. A format conversion unit that rearranges the byte array of the image raster data into a fixed common byte array, and the image data output from the format conversion unit is transferred to the printer as image data in a format that can be processed by the printer. Image data transfer means and the former
Image data output from the image conversion means
And a circuit for performing halftoning processing ,
After performing the color conversion process and the halftoning process
A printer control circuit for transferring the image data of 1. to the printer . 3. A pure hardware circuit.
The printer control circuit described. 4. a pure hardware circuit according to claim 2
The printer control circuit described. 5. A printer comprising the printer control circuit according to claim 1. Description: 6. A host device comprising the printer control circuit according to claim 1. Description: 7. A host device, a printer, and a printer control circuit connected to the host device and the printer, wherein the host device has a byte array forming one pixel data in an OS in the host device. Original image raster data creating means for creating the dependent original image raster data, parameter creating means for creating a byte order parameter indicating the byte array of the original image raster data, the byte order parameter and the original image And transmitting means for transmitting raster data to the printer control circuit, wherein the printer control circuit receives the original image raster data and the byte order parameter from the host device, and the byte order. Based on the parameters, the byte array of the original image raster data is converted into a certain common byte. Comprising a format converting means for rearranging the sequence, the image data transfer means for transferring the image data outputted from the format conversion means to the printer in the image data of the format that the printer can process, the receiving unit, the One image in the original image raster data
Effective byte number parameter indicating the effective byte number in the raw data
Data is also received from the host device, and the format conversion means sets the valid byte number parameter.
Data, and as a result, before the original image raster data
The effective number of bytes consists of the common byte array.
Less than the number of bytes of 1 pixel data, the common byte
An empty byte is generated in 1 pixel data composed of an array.
If it does, to fill the empty bytes
The null data of the
A printing system that performs mask processing to fill in . 8. A host device, a printer, and a printer control circuit connected to the host device and the printer, wherein the host device has a byte array forming one pixel data in an OS in the host device. Original image raster data creating means for creating the dependent original image raster data, parameter creating means for creating a byte order parameter indicating the byte array of the original image raster data, the byte order parameter and the original image And transmitting means for transmitting raster data to the printer control circuit, wherein the printer control circuit receives the original image raster data and the byte order parameter from the host device, and the byte order. Based on the parameters, the byte array of the original image raster data is converted into a certain common byte. Wherein the format conversion means for rearranging the sequence, the image data transfer means for transferring the image data outputted from the format conversion means to the printer in the image data of the format that the printer can process former
Image data output from the image conversion means
And a circuit for performing halftoning processing ,
After performing the color conversion process and the halftoning process
Printing system for transferring the image data of the above to the printer . 9. The printing system according to claim 7 , wherein the printer control circuit is a pure hardware circuit. 10. The printing system according to claim 8 , wherein the printer control circuit is a pure hardware circuit.