JPH08300745A - Image processing device and control method thereof - Google Patents

Abstract

PURPOSE: To reduce a capacity of a semiconductor memory to be used, by encoding a bit map data and storing it, creating an intermediate data based on other type of printing data, decoding the encoded bit map data so as to synthesize with the intermediate data for creating an image data. CONSTITUTION: A data of a receiving memory 310 in which a PDL data from a host computer is to be written is monitored for checking whether an image data is to be written or not. Next, a reversible encoding section 303 is started, the image data is encoded and accumulated in a hard disk 304. Successively, a character, a diagram, an image object expanding section 302 is started so as to analyze the PDL data and a character, a diagram, an image object data in an area for expanding on an edit memory 305 is created. An image data of character or diagram is expanded and plotted on the edit memory 305 based on the created object. The plotted data is compressed and written in a page memory 307.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus which receives print information from a host computer or the like and prints out an image, and a control method thereof.

[0002]

2. Description of the Related Art Conventionally, an image processing apparatus which receives print information from a host computer in a PDL format and outputs it, for example, a controller of a printer, is provided with a reception memory capable of receiving one page of PDL data. However, the PDL data is obtained by compressing character and graphic information in a command format and has a data capacity of about several hundred Kbytes. Further, even when receiving black and white bitmap data, the same amount of data can be received.

Further, in a controller of a printer capable of color printing, the receiving memory has a capacity of several megabytes.

[0004]

In the above conventional example, the PD
When handling color data in L, the data capacity does not increase so much only by attaching the color data of the color to be printed to the character and graphic data, but the bitmap data requires multivalued RGB data for each pixel. Therefore, the data capacity becomes large. For example, at a resolution of 600 dpi, A
For 4 sizes, if there are 256 gradations for each of the 3 primary colors, 4960 dots × 7015 dots≈4.35 Mbytes × 8 × 3 = 104.4 Mbytes, and 1 for A3 size
This is 04.4 Mbytes × 2 = 208.8 Mbytes. When data of such a capacity is received by the receiving memory as in the conventional example, it overflows and cannot be received.

In order to enable reception, when the maximum amount of received data is received in the reception memory, a reception waiting command is issued to the host computer so that the reception memory waits for the controller to print. However, the time until the next data is received in the receiving memory is an uncertain time because it depends on the print data output processing of the host computer, and it becomes difficult to make the drawing data output timing in the controller continuous. In the laser printer, it is impossible to form an image unless the video signals generated from the image data are continuous.

Furthermore, if the received print data includes a command for combining and drawing character or graphic data and bitmap data, the combining process becomes even more difficult, and it may not be possible to perform drawing according to the command.

In order to avoid these, it is necessary to prepare a storage medium having a large capacity such as configuring the receiving memory or the image memory to have a large capacity or preparing a large-capacity hard disk, which leads to cost increase.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an image processing apparatus capable of receiving one page of image data represented by multi-valued bit map data of PDL. And

It is another object of the present invention to provide an image processing apparatus and a control method therefor capable of editing the data in which the received image data and the character and graphic data are mixed and reproducing the data accurately according to the PDL information.

It is another object of the present invention to provide an image processing apparatus and a control method thereof for reducing the cost of the entire apparatus by reducing the capacity of the semiconductor memory used.

[0011]

[Means for Solving the Problems] and

The image processing apparatus of the present invention which achieves the above object has the following configuration. That is, an image processing apparatus that receives and processes data, and a receiving unit that receives print data including bitmap data and other types of data, and the print data received by the receiving unit are bitmap data. In some cases, a first encoding unit that encodes and stores bitmap data, a unit that creates intermediate data based on the other type of print data, and a bit encoded by the first encoding unit. The map data is decoded, and the data is combined with the intermediate data to create image data, and a combining unit, and a second encoding unit that encodes and stores the image data combined by the combining unit.

Further, a control method of an image processing apparatus according to the present invention for achieving the above object has the following constitution. That is, a control method of an image processing apparatus for receiving and processing data, comprising a receiving step of receiving print data including bitmap data and other types of data, and a step of converting the print data received by the receiving step into bits. If it is map data, a first encoding step of encoding and storing the bitmap data, a step of creating intermediate data based on the other type of print data, and an encoding step by the first encoding step A combining step of decoding the converted bitmap data and combining the data with the intermediate data to create image data; and a second encoding step of encoding and storing the image data combined by the combining process. Equipped with.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Before describing the structure of this embodiment, the structure of a laser beam printer suitable for applying this embodiment will be described with reference to FIGS. The printer to which this embodiment is applied is not limited to the laser beam printer, and may be a printer of another printing method.

FIG. 1 is a sectional view showing the structure of a first output device to which the present invention can be applied, for example, a case of a laser beam printer (LBP).

In the figure, reference numeral 1500 denotes an LBP main body, which inputs and stores print information (character code etc.) supplied from an externally connected host computer, form information, macro commands and the like. A corresponding character pattern, form pattern, or the like is created according to the above, and an image is formed on a recording paper or the like that is a recording medium.

Reference numeral 1501 is a switch for operation and L
It is an operation panel on which an ED display and the like are arranged.

A printer control unit 1000 controls the entire LBP main body 1500 and analyzes character information and the like supplied from a host computer. The printer control unit 1000 mainly converts character information into a video signal of a corresponding character pattern and outputs it to the laser driver 1502.

The laser driver 1502 is the semiconductor laser 1
A circuit for driving 503, which switches on / off a laser beam 1504 emitted from a semiconductor laser 1503 according to an input video signal. Laser light 15
A rotary polygon mirror 1505 is shaken in the left-right direction to scan and expose the electrostatic drum 1506 on the surface 04. As a result, an electrostatic latent image having a character pattern is formed on the electrostatic drum 1506.

This latent image is developed by a developing unit 1507 arranged around the electrostatic drum 1506 and then transferred to a recording paper. A cut sheet is used as this recording sheet, and the cut sheet recording sheet is stored in a sheet cassette 1508 mounted on the LBP 1500, and is taken into the apparatus by a sheet feeding roller 1509, a conveying roller 1510, and a conveying roller 1511, and electrostatically discharged. It is supplied to the drum 1506.

When color printing is possible, the LBP
In the main body 1500, toner of each color of yellow, magenta, cyan, and black is built in a developing unit 1507, each color is developed in a unit of one surface, transferred to an intermediate transfer member (not shown), and after transfer of four colors is completed. , Is transferred to recording paper.

Further, the LBP main body 1500 is provided with at least one or more card slots (not shown) so that an option font card and a control card (emulation card) having a different language can be connected to the internal font.

FIG. 2 is a schematic block diagram of the printer 1500 according to the embodiment. 12 is a printer CPU, R
A printing unit (printer engine) that controls access to various devices connected to the system bus 15 based on a control program stored in the program ROM of the OM 13 and is connected via the printing unit interface 16. An image signal as output information is output to 17.

The program ROM of the ROM 13 is shown in FIG.
The control program and the like executed by the CPU 12 as shown in the flowchart of FIG.

The CPU 12 can perform communication processing with a host computer (not shown) via the input unit 18, and
It includes a reception memory of 56 Kbytes and is configured to be able to notify a host computer (not shown) of information in the printer.

Reference numeral 19 denotes a RAM which functions as a main memory, a work area, etc. of the CPU 12, and is constructed so that the memory capacity can be expanded by an optional RAM connected to an expansion port (not shown). RAM1
Reference numeral 9 is used for a character / graphics and image object data storage area, an edit memory area (1 MB), a page memory area, an environment data storage area, NVRAM, etc., which will be described later.

Access to the above-mentioned external storage device 14 (hard disk device: HD in this embodiment) is controlled by a disk interface (DIF) 20. Further, the DIF 20 has a function of compressing / expanding multi-valued data by a reversible coding method, and reduces the storage capacity required for the outer HD 14.

The HD 14 stores the encoded image data. In the case of a hard disk, for example, the storage unit of 512 bytes / 1 sector, 64 sectors / 1 track is 3
It is a 2-Kbyte data transfer unit, and efficient data transfer is possible if the data is transferred in units of the transfer unit. In addition to the image data, font data, emulation programs, form data, etc. are stored. It is also possible.

Reference numeral 18 is an input unit such as the above-mentioned operation panel.
A switch for operation and an LED display are arranged.

FIG. 3 is a schematic diagram for explaining the main functions of the block of FIG. 2, in which the functions realized by hardware and software are mixed and illustrated.

The reception memory 301 is composed of an SRAM or the like included in the input section 18 and has a capacity of 256 Kbytes.

Character / figure / image object expansion unit 30
Reference numeral 2 expands each intermediate data that temporarily creates character data, graphic data, and image data for analyzing the PDL data written in the reception memory 301 and expanding it on the editing memory 305. To do. The image object is information that allows the compressed image data stored in the HD 304 to be read.

The reversible encoding unit 303 realizes the reversible encoding function in the DIF 20, compresses the image data read from the receiving memory 301 to 1/3 and stores it in the HD 304, which will be described with reference to the flowchart of FIG. In addition, the transfer from the reception memory 301 to the HD 304 is performed in units of 32 Kbytes and is repeated until the image data from the host computer is completed. After receiving the image data, the image data necessary for rendering and development is read and decoded. Further, the image data accumulated in the HD 304 is attached with search information that can be read when the image object is expanded. Also, H used here
The transfer speed of D is about 1 Mbyte / sec, but since the speeds are matched in the receiving memory 301 and the editing memory 305, the function can be satisfied even if it is not so high.

The edit memory 305 is included in the RAM 19,
It is a 1 Mbyte memory for drawing and developing characters, figures, and image objects with a fixed band length.
With a resolution of size 600 dpi, 1M bytes = 7015 bytes × 145 lines can be expanded.

The irreversible encoding unit 306 has an edit memory 30.
The drawing data expanded to 5 is compressed to 1/16 and written in the page memory 307. As you will see later in the flow chart, characters, graphics,
The process from the creation of the image object to the writing to the page memory 307 is repeated. When the data for one page is written, the data is read from the page memory 307, decoded, and output to the multi-level video I / F 308. Since it is irreversible at the time of decoding, data may be lost, but the print quality is hardly affected.

The page memory 307 is a lossy encoding unit 3
Since the data is compressed to 1/16 by 06, one page can be stored with a capacity of 202.8 M bytes × 1/16 = 13 M bytes even in A3 size.

The multi-level video I / F 308 has a function of converting the drawing data output from the lossy encoding unit 306 into a video signal to the engine 17.

FIG. 4 is a flow chart showing the processing from the reception of print data to the print output in the above configuration.

In step S401, the receiving memory 3
The PDL data from the host computer is written in 01.

In step S402, the data written in the receiving memory 301 is monitored to check whether the image data is written. If the image data is written, the process proceeds to step S408, and the image object data attached to it. Create an image object from the creation information.

In step S403, it is determined whether or not the image data has been written in the reception memory by 32 Kbytes. If the image data is not reached even if 32 Kbytes are reached, the process jumps to step S409.

If 32 Kbytes have been written, a reception refusal command (RNR) is transmitted from the input unit 18 to the host computer in step S404.

In step S405, the lossless encoding unit 30
3, the image data is read from the reception memory 301 and encoded.

In step S406, step S405
The image data encoded in (3) is stored in the HD 304.

In step S407, the reception memory 301
Determine if the above image data is finished.

In step S408, the character / graphic / image object expansion unit 302 is activated to receive the reception memory 301.
The PDL data written in the
Character / figure / image object data of the corresponding area for development processing on 5 is created.

In step S409, the character / graphic / image object expanding unit 302 is activated, and based on the created object, the character or graphic image data is expanded and drawn on the editing memory 305.

In step S410, in order to develop a necessary image based on the image object, the reversible code 303 is activated to read the corresponding image data from the HD 304.

In step S411, step S409 is performed.
In step S410, the image data read in step S410 is expanded on the character or graphic expanded in the edit memory 305 by an appropriate method. At this time, the image data is developed by a method such as overwriting, drafting, or OR according to the object information.

In steps S412 and S413, the lossy encoding unit 306 is activated, and the drawing data including the characters, figures, and images expanded in the editing memory 305 is 1 / 16th.
To page memory 307.

In step S414, it is determined whether all one page has been completed. When the data for one page is written, in step S415, the lossy encoding unit 306 is activated, the drawing data is read from the page memory 307, decoded, and output to the multi-value video I / F 308.

In step S416, the multi-value video I / F
At 308, the drawing data output from the lossy encoding unit 306 is converted into a video signal to the engine 17.

In step S417, the engine 17 prints out on a predetermined sheet.

As described above, the printer of this embodiment can receive the image data for one page. Further, the image data can be output according to the input print information by synthesizing the image data with the character data and the graphic data by a method according to the information of the object. Further, by compressing and storing the image data, the capacity of the storage medium can be small, and the device can be constructed at low cost.

The external storage device 14 of FIG. 2 and the external storage device of FIG.
HD304 is a hard disk, but low-cost storage element, flash memory, DRA with similar capacity
It is also possible to use M or the like.

[0055]

As described above, according to the image processing apparatus and the control method thereof according to the present invention, there is an effect that one page of image data represented by multi-valued bit map data on the PDL can be received.

Further, even when the received image data and the character and graphic data are drawn on one page, there is an effect that they can be accurately reproduced and output.

Furthermore, the edited and encoded image data can be temporarily stored in the page memory, and the video data to the engine section can be output in real time.

Further, there is an effect that the required storage medium capacity can be reduced and the cost of the entire apparatus can be reduced.

[0059]

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a configuration of an output device to which the present invention can be applied.

FIG. 2 is a block diagram illustrating a control configuration of the output device shown in FIG.

FIG. 3 is a block diagram illustrating main functions of the block diagram shown in FIG.

FIG. 4 is an operation flowchart of the block diagrams shown in FIGS. 2 and 3.

[Explanation of symbols]

 1 CPU 2 RAM 3 ROM 4 System Bus 12 CPU 13 ROM 19 RAM 3000 Host Computer 1500 Printer

Continuation of front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location H04N 1/41 G06F 15/66 310

Claims (11)

[Claims] 1. An image processing apparatus for receiving and processing data, comprising: receiving means for receiving print data including bitmap data and other types of data; and the print data received by the receiving means is bit data. In the case of map data, a first encoding unit that encodes and stores bitmap data, a unit that creates intermediate data based on the other type of print data, and an encoding unit that uses the first encoding unit. A combining unit that decodes the converted bitmap data and combines the data with the intermediate data to create image data; and a second encoding unit that encodes and stores the image data combined by the combining unit. An image processing apparatus comprising: 2. The receiving means has a memory of a predetermined capacity for storing the received print data, and the first encoding means sequentially stores the bitmap data of the predetermined capacity in the memory. The image processing apparatus according to claim 1, wherein the image processing apparatus performs encoding. 3. The first encoding means performs encoding according to a lossless encoding procedure, and the second encoding means performs encoding according to an irreversible encoding procedure. The image processing device according to claim 1 or 2. 4. The image processing apparatus according to claim 1, wherein the receiving unit receives print data created in a page description language format. 5. The image according to claim 1, further comprising an output unit that decodes the image data encoded and stored by the second encoding unit and prints it out. Processing equipment. 6. The image processing apparatus according to claim 1, wherein the output unit includes an electrophotographic printing mechanism. 7. A method of controlling an image processing apparatus for receiving and processing data, comprising: a receiving step of receiving print data including bitmap data and other types of data; and a printing operation received by the receiving step. When the data is bitmap data, a first encoding step of encoding and storing the bitmap data, a step of creating intermediate data based on the other type of print data, the first encoding A second step of decoding the bit map data encoded by the step, synthesizing the data with the intermediate data to create image data, and a second code for encoding and storing the image data synthesized by the synthesizing process A method for controlling an image processing apparatus, comprising: 8. The receiving step stores the received print data in a memory having a predetermined capacity, and the first encoding step comprises:
The method of controlling an image processing apparatus according to claim 7, wherein encoding is sequentially performed every time the memory stores the bitmap data of the predetermined capacity. 9. The encoding method according to claim 1, wherein the first encoding step is performed by a lossless encoding procedure, and the second encoding step is performed by an irreversible encoding procedure. The method for controlling an image processing apparatus according to claim 7, 10. The method of controlling an image processing apparatus according to claim 7, wherein the receiving step is a step of receiving data created in a page description language format. 11. The image according to claim 7, further comprising an output step of decoding the image data encoded and stored in the second encoding step and storing the image data for printing. A method for controlling a processing device.