JPH0410095B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic disk device, particularly a large-capacity
The present invention relates to a magnetic disk device suitable for transposing dimensional array data.

Image processing is a typical field that handles large amounts of two-dimensional array data. In such fields, when a processing device reads out large-capacity two-dimensional data stored in a magnetic disk device, or when it is read out, processed, and rewritten, the main memory of the processing device can only hold a portion of the data. Two-dimensional data is rarely accessed randomly. In many cases, as in TV scanning, access to unidirectional data on a horizontal line is normally repeated sequentially while shifting the line. The reason for this is that output (display, hard copy) of two-dimensional array data is usually of the scan type, and local processing of each point of the two-dimensional array data is also possible by scanning in the horizontal direction. On the other hand, some of the major processing processes for two-dimensional array data involve processing data at one point based on global data, such as two-dimensional Fourier transformation, rather than local processing for each point. In some cases, such processing can be realized by repeating the processing on a line-by-line basis in two directions, horizontal and vertical. Such processing is
Access to two-dimensional data is realized by first repeating one-dimensional access in the horizontal direction and then repeating one-dimensional access in the vertical direction. Therefore, it is necessary to read out two-dimensional array data that is stored continuously in the horizontal direction on a magnetic disk line by line in the vertical direction, for example, when you want to rotate the image data by 90 degrees and read it out for display output, or when you want to read and display the image data by rotating it by 90 degrees, or when you want to read and display the image data by rotating it by 90 degrees, This occurs when it is desired to read line data for vertical processing in two-step processing.

By the way, although conventional magnetic disk devices are capable of random access, unless a certain amount of serial data is input/output, the access time per unit of data becomes extremely long due to the waiting time for header rotation, etc. In other words, horizontal line data of two-dimensional array data on a magnetic disk can be accessed at high speed, but vertical line data requires an enormous amount of access time because the address is scattered for each data point. Therefore,
To read vertical line data from two-dimensional array data (M horizontal points and N vertical lines) on a magnetic disk for transposed display or vertical processing,
Conventionally, for example, two methods have been considered; the first method is to prepare a data buffer on the main memory of the processing device;
The horizontal line data is divided into a certain number of lines (n
line) and the vertical line data you want to obtain (m x n point data regarding m vertical lines)
By repeating this process N/n times, in which data is retained and other data is discarded, m vertical line data are obtained. The second method, as shown in Figure 1, is to repeatedly read out part of the data once stored on the disk to the main memory of the central processing unit, apply partial transposition processing, and write it again to the magnetic disk. was. Therefore, the first method requires a processing time for rearranging data on the main memory and a processing device for reading and discarding the same data (M/m-1) times.
OS overhead and disk device access dead time occur, and the second method also requires processing time for rearranging data on main memory, and reading array data from the disk device and writing it again in order to transpose and rearrange vertically and horizontally. The disadvantage was that processing equipment overhead was incurred.

As the second example above, the synthetic aperture radar processing shown in Fig. 2 is JRBennett and IGCumming:
Digital SAR Image Formation Airborne and
Satellite Results, Proc. of 13th Int.
Symposium on Remote Sensing of
Environment, p. 337-342 (1972). That is, to summarize, the two-dimensional data of the unprocessed radar hologram image is processed 19 line by line in the horizontal direction, stored at high speed in the magnetic disk device 19', and then transposed horizontally in the transposition process 20. The data is stored in the magnetic disk device 20' while being subjected to storage processing. Finally, magnetic disk device 2
Vertical direction line data is read out at high speed starting from 0', subjected to vertical direction processing 21 for each line data, and output as a processed image. The amount of data on one side of the synthetic aperture radar image is as high as 10 ³ to 10 ⁴ points, and as mentioned above, the processing time for the transposition process 20 is about the same as the original processes 19 and 21, resulting in the problem of increasing the total data processing time. It was hot.

An object of the present invention is to reduce the special processing load for transposition processing in a processing device, which allows two-dimensional data to be stored as continuous data in one direction, and read out as continuous data in a direction perpendicular to the direction at which it was stored. The purpose of the present invention is to provide a magnetic disk device that does not require any external interference.

An embodiment of the present invention will be described below with reference to FIG. Continuous data in the direction of an arrow 3 is transferred to the two-dimensional data transposition disk device 1 according to the present invention through a data bus 2. After all the two-dimensional data has been transferred, the data read out from this device has been transposed and is continuous data in the direction shown by arrow 4. The disk device 1 consists of a conventional magnetic disk device 5 and an additional device 6 for transposition. A conventional magnetic disk device 5 includes a magnetic disk 7, a rotary motor 8, a head 9, a drive device 10, and a control device 11. The additional device 6 includes a storage device 12 that stores a portion of two-dimensional data, and a transposition control device 13 that calculates addresses when reading and writing data from the storage device 12 and starts and controls the magnetic disk device. The transposition control device 13 is provided with a register 14 that stores the size of two-dimensional data, input/output mode, etc. 4a, b and c show the flow of processing in the transposition control device 13 of FIG. 3, where a is the process when an initialization command is received, b
c shows the process when a write transfer command is received, and c shows the process when a read transfer command is received.

The operation shown in FIG. 3 will be explained below. In the input mode, an initialization command to the device 1 is first sent from the signal line 15. The initialization command includes the vertical and horizontal data points K and L of the two-dimensional data, the number of bytes per data P, and the number of bytes Q of the storage device 12. During the initialization process, the transposition control device 13 uses the above parameters to obtain address calculation constants for the data input/output of the storage device 12 and the input/output of the magnetic disk 7, and sets them in the register 14. This calculation formula will be described later. At the end of the initialization command, an interrupt signal is sent to the signal line 16.

After initialization, a command to start transferring two-dimensional data is sent from the signal line 15. It is assumed that data transfer is continuous as shown by arrow 3. The storage device 12 has a fifth
As shown in Figure a, the number of lines k determined by the storage capacity is stored, and at that point the readiness signal (via signal line 16) for starting data transfer is stopped. Next, the transposition control device activates the magnetic disk control device 11 and sends the data on the storage device 12 to the magnetic disk device 5 in units of l×k size blocks, as shown in FIG. 5b. The address on the storage device is l
Each piece of data is discontinuous. Addresses on the magnetic disk can be continuous.

After all the data on the storage device 12 has been stored on the magnetic disk 7, the transposition control device 13 connects the signal line 16.
A data input preparation completion signal is issued by , and data storage is repeated from the next line number.

At the stage where all the two-dimensional data is stored, the transposition control device 13 receives data read activation, starts the magnetic disk device 5, reads out the data 17 shown in FIG. The vertical line data 18 is sent out. The addresses for reading from the magnetic disk device 5 are discontinuous for each block, unlike when writing. Also, when transmitting the vertical line data 18 from the storage device 12, the addresses are discontinuous for each data point. When the sending of vertical line data has been completed for all data on the storage device 12, reading from the magnetic disk device 5 is repeated.

The formulas for calculating the various address calculation parameters shown in FIG. 5 are shown below. In the figure, solid lines indicate data positions on the storage device, and double lines indicate sector addresses on the magnetic disk.

l = Q / KP ... (1) k = Q / LP ... (2) b = klP ... (3) l' = LP ... (4) b' = Q ... (5) d = lP ... (6) In the above embodiments, if the amount of two-dimensional data is enormous, it may not be possible to store it in one magnetic disk device. For example, in the case of synthetic aperture radar, the image processing unit may exceed 8192 x 16384 x 4 bytes, requiring several 300 megabyte disks. In this case, as shown in FIG. 5, a plurality of magnetic disk devices 5 are coupled to the additional device 6 for transposition. Two-dimensional data is divided and stored in each magnetic disk device 5. Generally, the data transfer speed of the magnetic disk device 5 is lower than the access speed of the storage device 12, so the storage device 12 is provided with the same number of memory ports 13 as the number of magnetic disk devices.
At the same time, data transfer between the magnetic disk 5 and the storage device 12 can be performed at high speed. Furthermore, if two sets of storage devices 12 are prepared and double buffered as shown in FIG. 6, data transfer on the signal line 14 can be performed simultaneously, and the time required to store data in the storage devices 12 is apparently eliminated, compared to normal It's no different from disk access.

By using a plurality of disk devices and two sets of storage devices, the transfer speed to the storage device 12 can be made the same as the transfer speed of the two-dimensional data transposition disk device of the present invention.

According to the present invention, a processing device has a special processing load for transposing two-dimensional data, which can store two-dimensional data as continuous data in one direction, and read out continuous data in a direction perpendicular to that at the time of storage. A magnetic disk device that does not need to be hung on the side can be realized.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a transposition process performed by a conventional central processing unit, FIG. 2 is a system configuration diagram that requires transposition processing of two-dimensional data, and FIG. 3 is a device configuration showing an embodiment of the present invention. 4 is a flowchart of processing in the transposition control device of FIG. 3, FIG. 5 is a diagram showing the state of data transfer in the present invention, and FIG. 6 is an example of realizing the present invention using multiple disks. FIG. 7... Magnetic disk, 10... Drive device, 11
...Control device, 12...Storage device, 13...Transposition control device.

Claims (1)

[Claims] 1. A magnetic disk device comprising a magnetic disk, a drive device, and a magnetic disk control device,
A storage device that stores one part of the two-dimensional array data and data from other devices are stored in the storage device in order, and then the order of the data in the storage device is changed and read out and transferred to the control device. The process is repeated, and finally, the first function stores all two-dimensional data on the magnetic disk, and the read data is temporarily stored in the storage device through the control device from discrete disk addresses obtained by predetermined calculations. A data transfer control device is provided which has a second function of reading data from the storage device so that the data string stored and input from another device becomes continuous data in the vertical direction and transferring it to another device. Features of magnetic disk device. 2. In the device according to claim 1,
The magnetic disk device is composed of a plurality of units, the storage device is equipped with a plurality of memory ports, and each of the plurality of magnetic disk devices is connected to one memory port to perform input/output with the storage device at the same time. A magnetic disk device characterized by (a) and (b). (a) The data transfer control device changes the order of data in the storage device, and at the same time divides the data and stores it in the magnetic disk device. (b) The data transfer control device reads data in small amounts from each magnetic disk device and configures the data in the storage device. 3. The device according to claim 1 or 2, wherein the storage device is composed of two sets,
A magnetic disk device characterized by the following (a) and (b). (a) When storing data from the channel to the magnetic disk, high-speed data transfer is performed in which data is transferred from the channel to the storage device and data is transferred from the storage device to the magnetic disk at the same time. (b) Perform the same high-speed data transfer as in (a) from the magnetic disk to the channel.