JPH05113859A - Image data printer device - Google Patents

Abstract

PURPOSE:To transfer image data, rotate the data by 90, and vary its magnifications and to reduce the cost by adding a buffer memory consisting of a small-capacity multi-port DRAM which is temporarily stored with the image data of plural lines instead of using an expensive multi-port DRAM as a page memory. CONSTITUTION:The image data printer device consists of the buffer memory 13 which consists of the multi-port DRAM and is temporarily stored with the image data of plural lines, a data transfer control part 12 which transfers the image data from the page memory 11 to the buffer memory 13, and a RAM- SAM data transfer control part 3 which transfers the data from the RAM part to the SAM part of the buffer memory 13 according to a line synchronizing signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic file device, a DTP (desk top publishing) device, and other image data printing devices for printing image data,
Especially, multi-port DRAM which is expensive as page memory
Instead of using, a buffer memory composed of a small-capacity multi-port DRAM for temporarily storing image data for a plurality of lines is added to enable image data transfer, 90-degree rotation, scaling processing, etc. And a low cost image data printing device.

[0002]

2. Description of the Related Art Image data printing apparatuses including a page memory for storing image data for printing, an output section for outputting image data, and a printer having a video interface such as a laser beam printer are available in various types. Are known. This image data printing apparatus is roughly classified into the following two methods.

The first method uses a multiport R as a page memory for storing an image for printing image data.
This is a method using AM. The second method is a method of directly transferring image data from a page memory storing an image for printing the image data to a page printer. First, a first conventional method, that is, a printer using a multiport RAM as a page memory will be described.

FIG. 7 is a functional block diagram showing an example of the essential structure of a conventional page printer using a multiport RAM as a page memory.
In the figure, 1 is a page memory, 2 is a data output section, 3
Is a RAM-SAM transfer controller, and 4 is a page printer.

The operation of the page printer shown in FIG. 7 is roughly as follows. The page memory 1 is a multiport R
It is composed of AM and stores image data (video data: image data) for one page (one screen). The image data stored in this page memory 1 is
Under the control of the RAM-SAM transfer control unit 3, the RAM of the page printer 4 is generated in accordance with the line synchronization signal generated by the page printer 4.
The data is transferred from the (random access memory) unit to the SAM (serial access memory) unit.

The data output section 2 reads data from the SAM section of the page memory 1 in accordance with the dot clock signal generated by the page printer 4, outputs image data (video data) to the page printer 4, and performs a printing operation. Be seen. However, since the multi-port DRAM that constitutes the page memory 1 is more expensive than a normal DRAM, there is an inconvenience that the cost increases when the amount of image data is large.

Next, a second conventional method, that is, a page printer which transfers image data directly from the page memory to the printer will be described.

FIG. 8 shows a conventional page printer which transfers image data directly from the page memory to the printer.
It is a functional block diagram which shows an example of the principal part structure. Reference numerals in the figure are the same as those in FIG. 7, reference numeral 5 indicates a page memory, and reference numeral 6 indicates a DMAC.

The conventional page printer shown in FIG.
Unlike the printer shown in FIG. 7, it is not necessary to use the multiport RAM as the page memory, which is advantageous in terms of cost. That is, since the image data is directly transferred to the printer, the page memory 5 usually has a memory capacity for one page.

The DMAC (Direct Memory Access Controller) 6 has a function of transferring the image data of the page memory 5 to the page printer 4 via the data output unit 2. However, if a function of rotating and scaling image data and printing the image data is required according to a user's request, a memory capacity for another one page is further required. At present, such demands are extremely large, and therefore the page memory 5 has a disadvantage that the memory capacity for one page is insufficient and the cost is increased because the memory capacity increases. ..

[0011]

SUMMARY OF THE INVENTION According to the present invention, there are inconveniences that occur in the conventional image data printing apparatus, that is,
If an expensive multi-port DRAM is used as the page memory, the cost becomes high, and if the original image is rotated by 90 degrees or the scaling processing is performed, one page or more of page memory is required. In addition, by solving the inconvenience that the cost becomes high, and by adding a buffer memory composed of a small-capacity multi-port DRAM for temporarily storing image data of a plurality of lines, transfer of image data, rotation by 90 degrees, It is an object of the present invention to provide a low-cost image data printing device that enables variable magnification processing and the like (the inventions of claims 1 to 3).

[0012]

According to the present invention, firstly,
A page memory that stores image data for printing,
An image data printing apparatus comprising an output unit for outputting image data and a printer having a video interface such as a laser beam printer is provided with a multiport D
A buffer memory configured by a RAM for temporarily storing image data for a plurality of lines, a data transfer control unit for transferring image data from the page memory to the buffer memory, and an R of the buffer memory according to a line synchronization signal.
RAM-SAM for transferring data from AM section to SAM section
And a data transfer control unit, which is configured to read data from the buffer memory and output the data to the printer.

Secondly, in the first image data printing apparatus, the data transfer control unit has a data rotation processing function for rotating the image data when transferring the image data from the page memory to the buffer memory. is there.

Thirdly, in the first image data printing apparatus, the data transfer control section has a data scaling function for scaling the image data when transferring the image data from the page memory to the buffer memory. It has a different structure.

[0015]

According to the present invention, in addition to the conventional page memory, a buffer memory composed of a small-capacity multi-port DRAM is used to transfer, rotate, and scale the image data in the page memory. (The inventions of claims 1 to 3). Then, the image data in the page memory is divided into blocks 1 to m each of which has n lines or a plurality of lines each consisting of n dots, and each block is processed as it is or rotated by 90 degrees and subjected to a / b scaling processing. , To a buffer memory composed of a small capacity multi-port DRAM and output to a printer.

Specifically, according to the invention of claim 1, when data is transferred from the page memory to the buffer memory,
The image data in the page memory is sequentially taken out in a block unit for n lines in the stored order, and the image data is alternately transferred to the buffer memory divided into two. According to the invention of claim 2, when data is transferred from the page memory,
The image data in the page memory is sequentially taken out in a block unit for n dots rotated by 90 degrees, and the image data is alternately transferred to the two-divided buffer memory.

According to the third aspect of the present invention, when the data is transferred from the page memory, the image data in the page memory is sequentially taken out in a block unit of n × (b / a) lines in a stored order, and a / The image data is alternately taken out in units of b-scaled blocks and alternately transferred to the two-divided buffer memory.

[0018]

The image data printing apparatus of the present invention will now be described in detail with reference to the drawings. This embodiment mainly corresponds to the invention of claim 1, but is common to the inventions of claim 2 and claim 3.

FIG. 1 is a functional block diagram showing an embodiment of the main configuration of the image data printing apparatus of the present invention. The reference numerals in the figure are the same as those in FIG. 7, and
Reference numeral 11 is a page memory, 12 is a data transfer control unit, and 13 is a buffer memory.

As described above, in the present invention, in addition to the page memory 11 similar to the conventional one, the buffer memory 13 constituted by a small-capacity multi-port DRAM is used to transfer, rotate and change the image data. It is configured to do double. The buffer memory 13 composed of this multi-port DRAM is composed of two banks (bank "0" and bank "1"), and each bank can store image data for n lines.

In the image data printing apparatus of the present invention shown in FIG. 1, the page memory 11 has a memory capacity for one page as in the conventional case, and stores image data for printing. The image data in the page memory 11 is divided into blocks 1 to m every n lines and processed in block units. The page memory 11 is the same as the page memory 5 described in FIG. 8 as a conventional example of the second method.

The buffer memory 13 is a memory for temporarily storing image data for a plurality of lines which are being scanned during printing, and is composed of a multiport DRAM. In the case of this embodiment, the buffer memory 13 only needs to have two banks having the same capacity as one block of the page memory 11. The data transfer control unit 12 is a transfer control unit having a function of transferring data from the page memory 11 to the buffer memory 13. Other configurations are the same as those of the page printer described with reference to FIG. 7 as a conventional example.

That is, the RAM-SAM transfer controller 4
Is a transfer control unit having a function of transferring data from a RAM (random access memory) unit of a buffer memory to a SAM (serial access memory) unit in accordance with a line synchronization signal generated by a printer. And
These respective units operate in parallel to perform printing.

In this embodiment, when the data is transferred from the page memory 11 to the buffer memory 13, the image data in the page memory 11 is sequentially taken out in a block unit for n lines and stored in two banks. The image data is alternately transferred to the buffer memory 13 (having two divisions).

FIG. 2 is a memory conceptual diagram for explaining an example of division of image data on the page memory 11 of the image data printing apparatus of the present invention. (1) shows division at the time of transfer of image data. FIG. 3 is a diagram illustrating an example of division during data rotation processing, and FIG. 3C is an example of division during data scaling processing.

In the first embodiment, when the image data is transferred, as shown in FIG. 2A, the image data stored in the page memory 11 is divided into a plurality of blocks 1 to m each consisting of n lines. It is divided and transferred alternately to the bank “0” and the bank “1” of the buffer memory 13 of FIG. 1 in block units. For example, n lines of image data of block 1 are transferred to one bank “0”, and then n lines of image data of block 2 are transferred to the other bank “1”. At the time of transfer to the other bank "1", the image data of the bank "0" transferred earlier is read by the data output unit 2 and sent to the page printer 4 for printing.

The image data of bank "0" is read out,
When the data transfer to the bank "1" is completed, the image data for n lines of the block 3 is transferred to the next bank "0". When transferring to this bank "0",
The image data of the bank “1” transferred earlier is read by the data output unit 2, sent to the page printer 4, and printed. After that, the same operation is repeated.

Next, the operation performed by the image data printing apparatus of the present invention will be described with reference to a timing chart.
FIG. 3 is a timing chart for explaining the operation of the image data printing apparatus of the present invention during the image data transfer processing.

First, the data transfer control unit 12 transfers the block 1 in the page memory 11 to the bank “0” of the buffer memory 13. When the transfer is completed, the page printer 4 is instructed to start printing. By this instruction,
The page printer 4 starts scanning, and the buffer memory 1
The contents of the bank “0” of 3 (image data of block 1) are output to the printer 4 side via the RAM-SAM transfer control unit 3 and the data output unit 2.

While the contents of bank "0" of buffer memory 13 are being output, data transfer control unit 12 transfers block 2 in page memory 11 to bank "1" of buffer memory 13. The transfer process in this case needs to be completed before the output of the last line of the bank “0” of the buffer memory 13 is completed, so that the transfer speed is set in advance so that such a condition is satisfied. It is set.

When the output of the bank "0" of the buffer memory 13 is completed, the contents of the bank "1" (image data of block 2) are transferred to the RAM-SAM transfer control unit 3 and the data output unit 2. The block 3 in the page memory 11 is transferred to the bank “0” of the buffer memory 13 while being output to the printer 4 side via the printer. Similarly, when the output of the image data of the block 2 from the bank "1" and the transfer of the image data of the block 3 to the bank "0" are completed, the image data of the block 3 is output from the bank "0". And the transfer of the image data of block 4 to the bank “1” is performed.

As described above, since the buffer memory 13 composed of the multi-port DRAM only needs to have two banks for storing one block of image data each consisting of n lines, it is composed of a small capacity merimo. It is possible to Here, the operation of the RAM-SAM transfer control unit 4 will be described. RAM-SAM transfer control unit 4
Transfers one line of image data stored in the RAM section of the buffer memory 13 to the SAM section every time a line synchronization signal is input from the page printer 4.

In this transfer operation, as shown in the seventh "data output section" in FIG. 3, the transfer memory starts from the first line of the head of the bank "0" of the buffer memory 13 to the last line of the bank "0". When the transfer is completed, the transfer of the first line of the head of the bank "1" is performed next. The same applies after that,
When the transfer of the last line of bank "1" is completed, next,
The first line at the beginning of the bank "0" is transferred, and the image data of the banks "0" and "1" are transferred alternately.

Next, with respect to the image data printing apparatus of the present invention, the operation at the time of the image data transfer processing will be shown by a flowchart. FIG. 4 is a flow chart showing the main processing flow at the time of image data transfer processing in the image data printing apparatus of the present invention. In the figure, # 1 to # 14 indicate steps.

When there is a print command in the image data printing device, the flow of FIG. 4 starts, and in step # 1,
The image data of the block 1 in the page memory 11 is transferred to the bank “0” of the buffer memory 13. When the transfer to the bank "0" is completed, the processes of step # 2 and step # 3 are started in parallel.

In step # 2, the image data of the block 2 in the page memory 11 is transferred to the bank "1" of the buffer memory 13. Further, in step # 3, the block BL to be transferred next is set to “3”, and the bank B to be transferred next is set.
N is set to "0", line L to be transferred next is set to "1", and the process proceeds to step # 4 to instruct the page printer 4 to start the printing operation.

When the process of step # 4 is completed, the processes of step # 5 and step # 6 are started in parallel. In step # 5, the image data of the block 1 in the page memory 11 is changed to the block BL (= 3) in the page memory 11.
Image data of the bank BN (=
"0"), and the process proceeds to step # 11.

At step # 6, the line synchronization signal from the page printer 4 is waited for.
7, the line L (= 1) of the image data stored in the RAM section of the buffer memory 13 is transferred to the SAM section. In step # 8, it is checked whether or not the transfer of the final line of the page is completed. If the transfer of the final line of the page is completed, the flow of FIG. 4 is terminated.

If the result of determination in step # 8 is that transfer of the last line of the page has not been completed, line L is set to "L + 1" in step # 9, and step #
Go to 10. In step # 10, it is checked whether the transfer of the line immediately before the last line of the block is completed, and if the transfer of the line immediately before the last line of the block is not completed yet, , Again, the process returns to the previous step # 6, and the same processing is performed thereafter.

On the other hand, as a result of the determination in step # 10, when the transfer of the line immediately preceding the last line of the block is completed, the process proceeds to step # 11. Step # 1
At 1, it is checked whether the bank BN to be transferred next is "0". If the bank BN is "0", the bank BN is set to "1" in step # 12, and if the bank BN is not "0", step # 13.
Then, the bank BN is set to "0".

In step # 14, the block BL to be transferred next is set to "BL + 1", the process returns to the previous steps # 5 and # 6 again, and the same processing is performed thereafter. The printing operation by the image data printing apparatus of the present invention is executed by the processing of steps # 1 to # 14 described above.

As described above, in the image data printing apparatus of the present invention, the page memory 11 similar to the conventional one and the multi-port DRAM are used to temporarily store the image data of a plurality of lines scanned during printing. The configured buffer memory 13 and the page memory 11 to the buffer memory 13
Data transfer control unit 12 having a function of transferring data to
Is provided, and the data transfer control unit 12 sequentially transfers the data in block units, so that an expensive multi-port DRA
It is possible to reduce M in a small capacity, and a low-cost page printer can be obtained.

[0043]

Third Embodiment Next, the third embodiment of the image data printing apparatus of the present invention will be described in detail. This example
This corresponds to the invention of claim 3. In the third embodiment, when the data is transferred from the page memory, the image data in the page memory is stored in the order of n × (b / a).
The lines are sequentially taken out in block units, a / b scaled blocks are taken out in block units, and the image data is alternately transferred to the two-divided buffer memory.

FIG. 6 is a diagram showing a third embodiment of the main configuration of the image data printing apparatus of the present invention.
Reference numerals in the figure are the same as those in FIG. When the image data is scaled and transferred, as shown in FIG. 2 (1), the image data stored in the page memory 11, that is, a plurality of blocks 1 to 1
Is divided into m blocks, extracted in block units as shown in FIG. 2 (3), temporarily stored in a memory such as a RAM provided in the data transfer control unit 12, and enlarged at a specified magnification. Alternatively, reduction scaling processing is performed, and the data is alternately transferred to the banks "0" and "1" of the buffer memory 13 configured by the multiport DRAM.

As described above, the function of the scaling process is executed by the data transfer control unit 12. In this scaling processing, the image data in the page memory 11 is taken out in 1-block units, temporarily stored in a memory such as a RAM provided in the data transfer control unit 12, and then scaled up or down at a designated scale. It suffices to perform processing. For this purpose, the data transfer control unit 12 may be provided with a CPU and a ROM or the like in which the program is stored.

In addition, the buffer memory 13 is provided for the image data of one block of the page memory 11 of FIG.
Two banks having a capacity corresponding to the maximum enlargement ratio capable of performing the scaling processing are prepared. In FIG. 5, two banks “0” and “1” in the buffer memory 13 are allocated to the 1 of the page memory 11.
The case where the image data of the block is enlarged and transferred is shown. Other configurations and operations are similar to those of the first and second embodiments. It should be noted that although the processing becomes somewhat complicated, it is also possible to make it possible to perform the previous rotation processing during this scaling processing.

[0047]

According to the first aspect of the invention, the cost of the image data printing apparatus can be reduced because the capacity of the expensive multi-port RAM is smaller than that of the conventional image data printing apparatus shown in FIG. It is possible to

According to the invention of claim 2, the image data printing apparatus capable of rotating the image data is realized, and the capacity of the conventional page memory shown in FIG. 8 can be reduced. The cost of the device can be reduced.

According to the third aspect of the present invention, an image data printing apparatus capable of scaling the image data is realized, and similarly, the page memory and the expensive multi-port RAM can be small in capacity. The cost of the printing device is reduced.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing an embodiment of the main configuration of an image data printing apparatus of the present invention.

FIG. 2 is a memory conceptual diagram for explaining an example of division of image data on the page memory 11 of the image data printing apparatus of the present invention.

FIG. 3 is a timing chart for explaining the operation of the image data printing apparatus of the present invention during the image data transfer processing.

FIG. 4 is a flowchart showing a main processing flow at the time of image data transfer processing in the image data printing apparatus of the present invention.

FIG. 5 is a diagram showing a second embodiment of the main configuration of the image data printing apparatus of the present invention.

FIG. 6 is a diagram showing a third embodiment of the main configuration of the image data printing apparatus of the present invention.

FIG. 7 is a functional block diagram showing an example of a main part configuration of a conventional page printer using a multiport RAM as a page memory.

FIG. 8 is a functional block diagram showing an example of a main configuration of a conventional page printer that transfers image data directly from a page memory to the printer.

[Explanation of symbols]

 2 data output unit 3 RAM-SAM transfer control unit 4 page printer 11 page memory 12 data transfer control unit 13 buffer memory

Claims (3)

[Claims] 1. An image data printing apparatus comprising a page memory for storing image data for printing, an output section for outputting the image data, and a printer having a video interface such as a laser beam printer. A buffer memory configured by a port DRAM for temporarily storing image data for a plurality of lines, a data transfer control unit for transferring image data from the page memory to the buffer memory, and a RAM of the buffer memory according to a line synchronization signal.
Image data printing apparatus, comprising: a RAM-SAM data transfer control unit for transferring data from a copy unit to a SAM unit, and reading the data from the buffer memory and outputting the data to the printer. 2. The image data printing apparatus according to claim 1, wherein the data transfer control unit has a data rotation processing function of rotating the image data when the image data is transferred from the page memory to the buffer memory. Image data printing device. 3. The image data printing apparatus according to claim 1, wherein the data transfer control unit has a data scaling processing function for scaling the image data when the image data is transferred from the page memory to the buffer memory. An image data printing device characterized by the above.