JPH04314182A - Image processing device - Google Patents

Abstract

PURPOSE:To perform the crisscross conversion of a raster format and a shuttle format and the processing of overlapped data by double buffering and to use a scanner/printer without being conscious of a specific format from a host computer. CONSTITUTION:The crisscross conversion of the raster format and the shuttle format is performed by allocating one address to one picture element and attaching two different addresses in buffer memory 100A, 100B. The buffer memory 100A, 100B comprise a double buffet, and respective buffer memory is divided into two main blocks 101, 103 and sub blocks 102, 104, and data written on the sub block is deleted in scan, and the data in the sub block of the buffer memory on one side is copied to the main block of the buffet memory on the other side in print.

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, and more particularly to a memory control technique for inputting image information, performing predetermined processing, and outputting the resultant image information.

0002

2. Description of the Related Art Generally, a buffer memory is provided between a computer and a peripheral device, and this memory absorbs differences in processing speed and transfer speed between the computer and the peripheral device. In most peripheral devices that are image data input and output devices, the image scanning format is raster format.

0003

[Problems to be Solved by the Invention] However, in the above conventional example, the image scanning format of the scanner and printer is not a general raster format but a format as shown in FIG. 2 (hereinafter referred to as shuttle format). In some cases, it is necessary to perform horizontal and vertical conversion in the scanning direction between the raster format on the computer side and the shuttle format on the scanner/printer side, and to process duplicate data.

[0004] The shuttle format will be described in detail below.

[0005] In FIG. 2, 201 represents one page of a manuscript or paper. 202 represents the head of a sensor or printer, and this head 201 itself moves in the raster direction indicated by the arrow 204. On the other hand, in the head 202, each pixel of the sensor or the nozzle of the printer head is lined up in a direction perpendicular to the raster direction 204, and data flows in the vertical direction shown by the arrow 203. Therefore, by moving the head 201 once, the memory area number 205 can be changed.
．． Part 1 is scanned or printed. In such a shuttle format, vertical and horizontal conversion is required for each area in order to convert the data into raster format data that is normally handled by the computer.

Furthermore, because one page is divided into areas like the head 202, several raster lines for the preceding and succeeding areas may be required in image processing. For example, when referring to the vicinity of a pixel of interest in smoothing processing, etc., it is necessary to refer to the data of the previous or subsequent area in the upper or lower part of the area. Considering this, in shuttle format, data from Sukiyana is
Extra data is added in the vertical direction of arrow 203, and although there is no overlapping nozzle in the printer head itself, extra data is added in the direction of arrow 203 for internal processing as data sent to the printer. must be added. Therefore, as shown at 206, data overlap occurs for each scan, and vertical/horizontal conversion must also be performed in units of this size.

The present invention has been made in view of the above-mentioned drawbacks of the conventional example, and its object is to have a shuttle-type I/F so that the head cannot be stopped during one shuttle scan. do not have. In other words, the objective is to provide an image processing device that can improve the throughput of the entire system when connecting a scanner/printer device that must continuously receive or supply data to a host computer. .

[0008]

[Means for solving the problem] Solving the above problems,
In order to achieve the object, an image processing apparatus according to the present invention includes a first storage means for storing data, a second storage means for storing data, the first storage means and the second storage means. A first access means accesses data in one of the storages in a raster format, and the other storage means, which is different from the storage means accessed by the first access means at the same time as the first access means, is accessed in a shuttle format. a second access means for accessing data, and a switching means for switching between the first storage means and the second storage means, storage means for data access by the first access means and the second access means, respectively; It is characterized by comprising:

[0009]

[Operation] According to this configuration, the first storage means and the second storage means each store data, and the first access means stores one of the first storage means and the second storage means. The second access means accesses data in a shuttle format, and the second access means accesses data in a shuttle format at the same time as the first access means, which is different from the storage means accessed by the first access means. The storage means to which data is accessed by the first access means and the second access means are respectively switched between the first storage means and the second storage means.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a block diagram showing an embodiment of an image processing apparatus according to the present invention. In the figure, numeral 1 indicates the image processing apparatus of this embodiment, and numerals 109 and 110 indicate a host computer and a scanner/printer apparatus connected to the apparatus 1, respectively. In the device 1, 111 is a data bus, 112 is an address bus, and 106 is a CPU that controls the entire device. 100A
is buffer memory, main block 101 and 102
It has a sub-block of 100B is also a buffer memory and has a main memory 103 and a sub memory 104. 105 is a selector for the data bus 111 and address bus 112;
Two sets of buffer memories 100A (101
and 102), 100B (103 and 104) (total of 4 blocks) are switched to the CPU side or the video side. The CPU side is the raster format host computer 109 side, and the video side is the shuttle format scanner/printer device 110 side. Further, 107 is an external I/F (interface) for communicating with the host computer 109, and 108 is the scanner/printer device 1.
Each video I/F that communicates with 10 is shown. 121 is a ROM which stores programs for the operation of the CPU 106, such as programs according to the flowchart of FIG. 122 is a RAM, which functions as a work area for the program in the ROM 121;

The operation of the above configuration will be explained.

FIG. 6 is a flowchart illustrating the image processing operation of this embodiment.

First, during scanning, the CPU 106
The video I/F 108 is set so that it can access the main block 103 and sub-block 104 of the buffer memory 100B (step S1), and the CPU 106 itself is set so that it can access the main block 101 and sub-block 102 of the buffer memory 100A (step S1).
Step S2). Next, image data is sent to the apparatus 1 from the scanner section of the scanner/printer apparatus 110 in a shuttle format. Video I/F 108 generates an address and transfers the sent image data to memory block 103.
and is written in the sub-block 104 in shuttle format (step S3). At the same time, the CPU 106 reads data in raster format from the main block 101 to which data has already been written by the video I/F 108 in the previous operation, and transfers it to the external I/F 107. This external I/F 107 is, for example, SCSI,
The image is transferred to the host computer 109 (step S4). At this time, the data of subblock 102 is discarded.

Next, in the selector 105, contrary to the previous step, the CPU 106 sets the video I/F 108 to access the main memory 101 and the sub memory 102 (step S5), and the CPU itself accesses the main memory 103. and the submemory 104 is set so that it can be accessed (step S6). The CPU 106 reads data in raster format from the main block 103 that has already been written in the previous operation, and sends the data to the host computer 109 via the external I/F 107 (step S7).
. At the same time, the buffer memory 100A has scanner/
Data from the scanner section of printer device 110 is written in shuttle format by video I/F 108 (step S8). Repeat these operations (step S9
).

Furthermore, since the operation during printing is similar to the operation during scanning described above, the explanation will be omitted, but the operation is slightly complicated due to the processing of duplicate data.

FIG. 3 is a diagram showing four states of access to the buffer memory during printing according to this embodiment.
The details will be described later, but the four states (1), (2),
By repeating (3) and (4), double buffering operation becomes possible.

FIG. 4 is a diagram showing the structure of the buffer memory of this embodiment.

Main blocks 101 and 103 each have the size of memory 205 shown in FIG. Further, sub-blocks 102 and 104 are memory portions for duplicate data, and together with the main block constitute an area containing duplicate data, as shown by 206 in FIG.

In the buffer memory 100A, the main block 101 is divided into areas A-M1 and A-M2, as shown in FIG. This A-M1 is the same size as the sub-block 102, ie, A-S. This also applies to buffer memory 100B.

The operation will now be explained using FIG. In state (1), the contents of A-S (subblock 102) are copied to B-M1 (main block 103). In the next state (2), the continuation copied in (1) above, that is, the CPU is stored in B-M2 (main memory 103).
106 is written in raster format. Subsequently, the data is also written in B-S (subblock 104) in raster format. At the same time as these, buffer memory 100A
The video I/F 108 reads out the contents in shuttle format.

In the following state (3), the data of B-S (sub-block 104) is transferred to A-M1 (main memory 101).
). Next, in the state (4), the continuation of A-M1 (main memory 101) is A-M2 (main memory 1).
01), raster format data is written from the CPU 106, and the continuation thereof is also written to A-S (sub memory 102). At the same time as this, the buffer memory is 100.
The data of B is read out by the video I/F 108 in shuttle format. Then, the process returns to state (1) and repeats these four states in order. Each of these four states is performed by setting the selector 105 by the CPU 106 in FIG. In state (1), the CPU 106 is
The data bus and address bus from situation(
In 2), both the main and sub blocks of the buffer memory 100A are connected to the video I/F 108 side, and the main and sub blocks of the buffer memory 100B are connected to the CPU 106 side. In state (3), the main block 101
and sub-block 104 are connected to the CPU 106 side. In state (4), the buffer memory 100A is
6 side, buffer memory 100B is video I/F 108
connected to the side.

FIG. 5 is an external perspective view showing the structure of the buffer memory according to this embodiment.

The structure of the buffer memory is such that vertical and horizontal conversion is performed only by how addresses are given, so that one pixel has R, G, B
Alternatively, each color of C, M, Y, and K is composed of 8 bits, that is, 32 bits. For example, block 1 in FIG.
As shown in 01 and 102, it is configured to have 4096 pixels in the raster direction and 128 pixels and 16 pixels in the vertical direction. At this time, 4096 is a good value, exceeding the number of pixels in the short direction of A4 size paper at 400 dpi, 128 is the number of nozzles in the printer head, and 16 corresponds to duplicate data for image processing. D this buffer memory
To specifically configure it with RAM, as shown in Figure 5, 4
The main block consists of 16 bit-type 1M DRAMs (256K bits x 4 bits), and 4-bit type 256K DRAMs (64K bits x 4 bits).
A sub-block is made up of 8 pieces.

As explained above, according to this embodiment,
Vertical and horizontal conversion between raster format and shuttle format and processing of duplicate data can be performed using bubble buffering, allowing the host computer to use the scanner/printer without having to be aware of special formats. Now, in the above-described embodiment, the case of a color image is shown, but the same applies to a monochrome image, and in this case, one pixel is composed of 8 bits instead of 32 bits.

[0026] Also, the buffer memory size of 4096 x (128 + 16) is equivalent to a head of 128 nozzles and an A4
The specifications are 400 dpi, and of course memory configurations of different sizes can be obtained depending on the system resolution, paper size, and number of nozzles in the head.

The present invention may be applied to a system made up of a plurality of devices, or to a device made up of one device. It goes without saying that the present invention can also be applied to cases where the present invention is achieved by supplying a program to a system or device.

[0028]

[Effects of the Invention] As explained above, according to the present invention,
Vertical and horizontal conversion between raster format and shuttle format and processing of duplicate data can be performed using bubble buffering, allowing the host computer to use the scanner/printer without having to be aware of special formats.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of an image processing apparatus according to the present invention.

FIG. 2 is a diagram illustrating a general shuttle format.

FIG. 3 is a diagram showing four states of access to the buffer memory during printing according to the present embodiment.

FIG. 4 is a diagram showing the configuration of a buffer memory of this embodiment.

FIG. 5 is an external perspective view showing the configuration of the buffer memory according to the present embodiment.

FIG. 6 is a flowchart illustrating the image processing operation of this embodiment.

[Explanation of symbols]

101,103 Main block 102,104 Subblock 105 Selector 106 CPU 107 External I/F 108 Video I/F 109 Host computer 110 Scanner/Printer 111 Data bus 112 Address bus 121 ROM 122 RAM

Claims (1)

[Claims] 1. A first storage means for storing data, a second storage means for storing data, and one of the first storage means and the second storage means is stored in a raster format. a first access means for accessing data; and a second access means for accessing data in a shuttle format, the other storage means different from the storage means accessed by the first access means at the same time as the first access means; ,
An image processing apparatus comprising: a switching means for switching storage means to which data is accessed by the first access means and the second access means, respectively, between the first storage means and the second storage means. .