JPH04213776A - Method and device for processing image - Google Patents

Abstract

PURPOSE:To constitute the device so that image data rotated by 90 degrees can be sent to a printer almost simultaneously with reading out the image data from an image memory by using a comparatively small memory area. CONSTITUTION:The device is provided with an image memory 1, a means for executing read-out to this image memory 1 by a direct access, a line buffer 5 for storing image data which is read out, a printer 6, and a control part 7 for controlling a transfer operation of the image data from the image memory 1 to the printer 6, and the control part 7 writes the data by a word unit in the line buffer 5 at the time of data transfer, and on the other hand, reads it out by a bib unit from the line buffer 5, and executes a rotational processing to the image data.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing method, and more particularly to an image processing method and apparatus that can easily rotate an image and output it to a printer or the like.

0002

2. Description of the Related Art Conventionally, image data on a memory has been rotated by 90 degrees and output to a printer or the like by using an LSI for image processing.

0003

[Problem to be Solved by the Invention] However, in such a conventional image processing method, it is necessary to transfer the image data rotated by 90 degrees to the memory for image processing again and develop it on this memory. Therefore, depending on the image data to be processed, a very large work area is required, and the data must be sent at the speed of the printer, so the printer cannot output the image data rotated in memory until it is completed. There was a problem that I couldn't do it.

The present invention has been made in view of the above problems, and its purpose is to send image data rotated by 90 degrees to a printer almost at the same time as reading the image data from the memory, without requiring a large work area. An object of the present invention is to provide an image processing method and an apparatus that can perform image processing.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides an image processing device with one or more buffers, writes data into the buffer in units of words, and reads data in units of bits. 90 image data
The gist is that it rotates by a degree.

[0006]

[Operation] With the above configuration, image data is read out from the memory in word units by direct access operation, and an address after rotation is given for each word.
transferred to the buffer. After the image data is written into a buffer, it is read bit by bit and sent to an output unit such as a printer. As a result, an image rotated by 90 degrees is output from the output unit.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing an embodiment of an image processing apparatus for implementing the method of the present invention. In this figure, reference numeral 1 denotes an image memory in which image data subjected to rotation processing etc. is stored and expanded; 2 an image bus serving as a transmission path for image data written to and read from the image memory 1;
3 is a direct memory access controller (DMAC) that writes and reads image data to and from the image memory using direct access operations; 4 is an image memory 1;
5 is a line buffer serving as a buffer means for temporarily storing data read from the image memory 1; 6 is data transferred from the line buffer 5; 7 is a control unit that is composed of a CPU and controls the operation of each functional unit for image processing; 8 is a signal feeding path between each of the functional units and the control unit 7; This is a local bus. In this embodiment, one line buffer 5 is provided, but a plurality of line buffers may be provided.

FIG. 2 is a schematic diagram for explaining the storage state of image data on the image memory 1. As shown in FIG. In this embodiment, the image memory 1 stores (n×
m) Word image data is stored. FIG. 3 shows an enlarged view of the word portion 1-1 in FIG. 2, and this word portion 9 has a length of (L+1) bits. FIG. 4 is an enlarged diagram showing an example of the contents of the line buffer 5. As shown in FIG. This line buffer 5 includes a first buffer 5a and a second buffer 5.
It is composed of b. Each of the first buffer 5a and the second buffer 5b has a buffer block that can store n words of image data (i.e., length n).
L+1) are provided, and one group of data in the image memory 1 in the column direction is stored.

FIG. 5 is a diagram illustrating how address generation section 4 generates addresses. The address starts from the start value, generates the address by adding a positive offset value (for example, 1) (n-1) times, and then subtracts the negative offset (i.e., -1) after the addition to generate the address. let By repeating these operations, the entire address is generated.

The operation of the control device having such a configuration will be explained below. In the image processing apparatus of this embodiment, in order to perform image rotation processing (for example, 90 degree rotation processing), the control section 7 issues an access command to the image memory 1 to the DMAC 3, and also issues an instruction to the address generation section 4 to access the image memory 1. An address generation command for image rotation is issued to the image rotation address. As a result, the address generation unit 4 generates a 90% response to the original image data.
The DMAC 3 reads the image data in word units from the image memory 1 and transfers this data from the image bus 2 to the line buffer via the local bus 8 according to the address specified by the address generator 4. Send to 5.

As shown in FIG. 5, the image memory 1 is read out according to the address (1-1) from the address generator 4.
) → (1-2) → (1-3), →
...→ (1-n), →... → (2-n
), →…… → (m-1) → (m-
2) → (m-3), →…… → (m-n
) is read out word by word in order, and written to the line buffer 5 bit by bit. FIG. 4 shows a situation in which words 1-1 to 1-n are read out from the image memory 1 in word units and written into the first buffer 5a in bit units. From this first buffer 5a, from bit 0
Data is sequentially output to the printer 6 up to bit L. This results in a rotation of 90 degrees by (L+1)×n bits. In this way, from the first buffer 5a,
While outputting data to the printer 6, image data from word 2-1 to word 2-n is read out from the image memory 1 in word units, written to the second buffer 5b in bit units, and the next It is treated as printer output data. By repeating these operations, (
The (n×m) word data is sent to the printer 6 as (m×n) word data. The reason why the line buffer 5 is divided into two buffers 5a and 5b is to send data to be printed even faster to the printer 6 by toggling between the first and second buffers 5a and 5b. However, the number of buffers can be changed depending on the speed of transferring and writing from the image memory 1 to the line buffer 5, the speed of sending image data to be printed, etc.

0012

[Effects of the Invention] As explained above, according to the present invention,
A buffer is provided in the image processing device, and the image data is rotated 90 degrees by writing data into the buffer in word units and reading it out in bit units. This enables high-speed processing without using extra work area in memory. Images can be rotated 90 degrees.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of an image processing device for implementing the present invention.

FIG. 2 is a schematic diagram for explaining the order of memory access on the image memory in the embodiment.

FIG. 3 is a schematic diagram showing the minimum unit of data read from the image memory in the embodiment.

FIG. 4 is a schematic diagram for explaining data writing to a buffer in the embodiment.

FIG. 5 is a schematic diagram of an address generation mechanism in the embodiment.

[Explanation of symbols]

1 Image memory 2 Image bus 3 DMAC 4 Address generation section 5 Line buffer 6 Printer 7: Control section 8: Local bus

Claims (3)

[Claims] Claim 1: One or more buffer means are provided between an image memory in which image data to be processed is stored and an image output means, and data is written to the buffer means in word units, while data is written from the buffer means to the image output means. An image processing method characterized in that image data is rotated by reading it bit by bit. 2. An image memory in which image data is stored, means for performing a read operation on the image memory by direct memory access, means for generating address information of the image memory, and an image memory for reading out image data from the image memory. A line buffer that temporarily stores image data, a printer that performs printing by transferring image data from the line buffer, and a line buffer that writes data in word units to the line buffer in the operation of transferring image data from the image memory to the printer. , a control means for rotating image data by reading it bit by bit from the line buffer. 3. The image processing apparatus according to claim 2, wherein the line buffer is composed of a plurality of buffer means.