JPS6149246A - Image rotation processing system - Google Patents

Abstract

PURPOSE:To increase the image rotation processing speed by reading the image information out of a rectangular area divided from a 2-dimensional memory to give rotation conversion to the read-out information through a vertical/horizontal conversion buffer and storing the converted image information in a prescribed area of the 2-dimensional memory. CONSTITUTION:When an image within a 2-dimensional memory 1 is rotated at an angle equivalent to multiples of 90 deg., an area to be rotated in the image is divided into rectangular areas of each prescribed bit width. The address information on the divided rectangular areas are produced by an address counter 4. Then the image information is read out of the memory 1 through a read/write control part 2 by means of the address given from the counter 4 and stored in a vertical/horizontal conversion buffer 3. The address information is obtained from the counter 4, and the corresponding image information undergoes the vertical/horizontal conversion through the buffer 3 to be stored in a latch 6. This converted image information is stored in a position in the memory 1 where the prescribed rotation is carried out via a control part 2.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image rotation processing method, in particular, a method for rotating an image within a predetermined rectangular area in an image developed on a two-dimensional memory.
When rotating an integer multiple of 0 degrees, the image information in the rotated rectangular area is stored in the vertical/horizontal conversion buffer, and the image information rotated vertically and horizontally is stored in the original rectangular area, thereby rotating the image at high speed. This relates to an image rotation processing method.

(Problems to be solved by the prior art and the invention) A two-dimensional memory, for example, a memory as shown in FIG. There are cases where it is desired to rotate an image stored in a dimensional memory 90 degrees at high speed.In this case, when writing the image in the X direction shown in FIG. 7(B), the configuration of the 2D memory is FIG. 7(A) Address #1 of the illustrated memory,
It is sufficient to sequentially write 117 images in parallel every 8 bits like #2, #3, . . . .

However, when writing an image in the Y direction shown in Figure 7 (B), 90 degrees or 270 degrees
When writing an image rotated by a degree, address # of the illustrated memory in FIG. 7 (8) that constitutes the two-dimensional memory is
Image information must be sequentially written into the first bit (MSB) of 1, #4, #7, etc., and then image information must be written into the second bit in units of one focus.

As a result, the number of accesses to the two-dimensional memory increases, causing a problem in that the writing speed drops significantly, for example, to one-eighth.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention provides image information of the rectangular area to be rotated in the vertical and horizontal directions when rotating an arbitrary rectangular area in an image developed on a two-dimensional memory by an integral multiple of 90 degrees. The purpose is to rotate an image at high speed by storing 117 images that have been once stored in a conversion buffer and subjected to a predetermined rotation in the original rectangular area of a two-dimensional memory. Therefore, the image rotation processing method of the present invention rotates an image stored in a two-dimensional memory to an angle that is an integral multiple of 90 degrees. An address generation method that divides an area of an image stored in the image into rectangular areas of a predetermined bit width to be rotated by an angle that is an integral multiple of 90 degrees, and generates an address for sequentially reading image information in the divided rectangular areas. a read/write control unit that reads image information in the divided rectangular areas from the two-dimensional memory using the addresses generated by the address generation unit, and stores image information that has undergone predetermined rotational conversion; Lead
and a vertical/horizontal conversion buffer for vertically and horizontally rotating the image information read by the write control unit, and the image information subjected to the vertical/horizontal rotation conversion by the vertical/horizontal conversion buffer is transferred to the two-dimensional image information by the read/write control unit. It is characterized by being stored in a predetermined area of memory.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a configuration diagram of one embodiment of the present invention, FIGS. 2 to 5 are operation explanatory diagrams explaining the operation of the configuration of one embodiment of the present invention shown in FIG. 1, and FIG. 6 is an illustration of another embodiment of the present invention. An example configuration diagram is shown.

In the figure, 1.1-1.1-2 is memory, 2.2-1.2-
2 is a read/write control unit, 3.3-1.3-2 is an vertical/horizontal conversion buffer, 4.4-1.4-2 is an address counter, 5 is a decoder, 6.6--1.6-2 is latch, 7
is MPX (multiplexer), and 8-1 to 8-8 are shift registers.

represent.

FIG. 1 shows an embodiment in which an image stored in a rectangular il area is extracted using a set of illustrated memories 1, rotated by an integral multiple of 90 degrees, and then written into the original rectangular area. shows.

A memory 1 in the figure is for storing image information, and is configured in the form of the two-dimensional memory described above. The image information stored in the memory 1 is read out by the illustrated read/write controller 2 and stored in the illustrated vertical/horizontal conversion buffer 3 in order to rotate the image to an angle that is an integral multiple of 90 degrees. Address information generated by the illustrated address counter 4 is stored in the vertical/horizontal conversion buffer 3 by a decoder 5.
Supplied via. In correspondence with the supplied address information, image information that has been vertically and horizontally converted as described later, and image information that has been rotated by an integral multiple of 90 degrees are sequentially stored in the latch 6.

Then, the stored image information is sequentially stored in the memory 1 at a predetermined rotated position via the read/write control section 2. At this time, the address counter 4 is
Address information for reading out the image information stored in a predetermined rectangular area in the memory 1 and address information for storing the image information after rotation processing are supplied via the read/write control unit 2, respectively. .

The operational concept of rotationally converting an image by the vertical/horizontal conversion buffer 3 in the configuration of one embodiment of the present invention shown in FIG. 1 will be explained with reference to FIG.

Figure 2 (A) Addresses #1 and #2 in memory as shown
, #3..., each consisting of 8 bits, is developed into a two-dimensional memory as shown in Figure 2 (B), then CB in Figure 2 ) To increment data in the X direction shown in the figure, it is sufficient to sequentially write every 8 bits to the addresses #1, #2, #3, . . . of the memory shown in FIG. 2(A), as described above. However, as shown in Figure 2 (C), 90
To write image information rotated counterclockwise, address #3, #6, #9 of memory shown in Figure 2 (A).
It is not possible to write image information one bit at a time, such as writing image information to the first bit of ... and then writing image information to the second bit, and the image rotates at high speed. Unable to write information.

Therefore, in this embodiment, the illustrated image information (
1, 2, 3...) in 8-bit positions and stored in the vertical/horizontal conversion buffer 3 shown in Figure 1, and the image information retrieved in the form of vertical/horizontal conversion is read out in 8-bit units as shown in Figure 2 (C). The configuration is such that the data is stored in the memory shown in FIG. 2(A).

Next, the rotation processing when the image area to be rotated is divided into 8-bit x 8-bit areas g11 will be specifically explained using FIGS. 3 to 5.

First, the necessity of dividing into 8 bits x 8 bits area will be explained to Pl.

The rotation processing (vertical/horizontal conversion processing) according to the present embodiment is performed as the number of bits (/) that the vertical/horizontal conversion buffer 3 performs vertical/horizontal conversion at one time is large, and as the number of bits accessed at one time in the two-dimensional memory increases, the rotation processing becomes more accurate. Increases speed. However, there is a limit to the number of bits that can be converted vertically and horizontally at one time using the vertical/horizontal conversion buffer 3 (if this is done, the scale of the hardware will increase. The number of bits that can be accessed by the memory 1 at one time, for example, 8 bits (the number of nodes corresponding to 1 byte) is adopted to achieve overall efficiency.

Figure 3 (A> Image area to be rotated in the figure "1"'
As shown in FIG. 4(A), image information consisting of 1 byte length in the X direction (8 bits, which is the number of bits that can be accessed at one time) is stored in 1 byte length in the Y direction. Image information consisting of corresponding 8-bit length is stored respectively.

In other words, image information consisting of 8 bits x 8 and nodes is stored as shown in the figure in a manner that can be aged in units of 8 bits at a time in the X direction.

On the other hand, in the form shown in Figure 4 (A), Figure 3 (A) ・
The image information stored in the illustrated image areas "1' to "201, respectively, rotated 90 degrees counterclockwise is displayed in the form shown in FIG. 4(B) in FIG. 3 CB.
) are stored in the illustrated image areas "1" to "20", respectively. At this time, the rotation process (vertical/horizontal conversion process) from the illustrated image information in FIG. 3 (A) to the illustrated image information in FIG. (Shift register with 8-pin differential lυ input and serial output function)
The rotation process shown in FIGS. 3 and 4 will be described below with reference to FIG.

In the fifth section, 8-1 to 8-8 in the figure are shift registers for respectively storing 8-bit parallel data and sequentially taking out serial data from the other end. Eight shift registers 8 as shown in FIG.
-1 to 8-8 are arranged respectively, and the illustrated image information in FIG. 4 (A) stored in the illustrated image area "1" in FIG. 3 (A) is sequentially read out from the illustrated memory 1 in FIG. The data are sequentially stored in shift registers 8-1 to 8-8 as shown in the figure (bits 1 to 8, bits 9 to 16, bits 17 to 24, etc.).

Then, eight pieces of serial image information output from the shift registers 8-1 to 8-8 all at once in synchronization with a clock signal (not shown) from the right end are sequentially stored in the rough register. The image information consisting of a set of 8 coughs memorized is represented by being rotated 90 degrees counterclockwise as shown in FIG. The data are sequentially stored in the area as shown in FIG. 4(B). The predetermined area is determined by calculating an address at which the rotated image information should be stored. In this way, the image area in FIG.
The image information as shown in FIG. 4 (A), which was stored in 1'', is stored in the image area "1" of FIG. 3 (B) as shown in FIG. 4 (B). will be done.

In the same manner, image information as shown in FIG. 4(A) is provided for each of the image areas "2" to "20" in FIG. Figure 3 (B) shows the image information of the shape rotated clockwise.
Illustrated image 5■ Area F2" to "20" are respectively stored. As a result, all of the illustrated image area in FIG. 3(A) is rotated 90 degrees counterclockwise. FIG. 3(B) Further, in order to rotate the image information 90 degrees clockwise, the positions of the image information stored in the soft registers 8-1 to 8-8 may be reversed, or the direction of shifting may be reversed.

FIG. 6 shows an example in which two sets of illustrated memories 1-1 and 1-2 are used, and in order to simplify the explanation, image information successively read out from memory 1-1 is rotated. The figure shows an example of a configuration in which image information is sequentially stored in memory 1-2 in a continuous manner. The middle vertical/horizontal conversion buffers 3-1 and 3-2 are stored in the memory 1.
This is for alternately storing image information to be rotated read from -1. By adopting this configuration, image information is sequentially read from the image area to be rotated from the memory 1-1 and stored in the vertical/horizontal conversion buffer 3-1 or 3-2, and the '#1 horizontal conversion buffer The image information rotated by 3-1 or 3-2 can be sequentially switched using an MPX (multiplexer) 7 shown in the figure and stored continuously in the memory 1-2. Therefore, compared to the case where image information is read from one memory 1, rotated using the vertical/horizontal conversion buffer 3, and the rotated image information is written again to the original image area, as in the configuration shown in FIG. 6th
The configuration shown in the figure is capable of continuously reading the imager information from either memory 1-1 or 1-2 and storing the rotated image information in the other memory 1-1 or 1-2. Rotation processing can be performed at almost twice the speed.

〔Effect of the invention〕

As explained above, according to the present invention, when rotating an image developed on a two-dimensional memory by an integral multiple of 90 degrees,
Image information is read from the rectangular area where the image to be rotated is located, temporarily stored in the vertical/horizontal conversion buffer, and the desired rotated image information is acquired into the original rectangular area, so image rotation can be performed at high speed. I can do it.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of one embodiment of the present invention, FIGS. 2 to 5 are operation explanatory diagrams explaining the operation of the configuration of one embodiment of the present invention shown in FIG. 1, and FIG. 6 is an illustration of another embodiment of the present invention. FIG. 7 is an explanatory diagram illustrating a conventional image rotation processing method. In the figure, 1.1-1.1-2 is memory, 2.2-1.2-
2 is a read/write control unit, 3.3-1.3-2 is an vertical/horizontal conversion buffer, 4.4-1.4-2 is an address counter, 5 is a decoder, 6.6--1.6-2 is latch, 7
represents MPX (multiplexer), and 8-1 to 8-8 represent shift registers.

Claims (1)

[Claims] An image rotation processing method that rotates an image stored in a two-dimensional memory to an angle that is an integer multiple of 90 degrees, comprising: a two-dimensional memory that stores the image; and an integer of 90 degrees in the image stored in the two-dimensional memory. an address generation unit that divides an area to be rotated at a double angle into rectangular areas each having a predetermined bit width and generates an address for sequentially reading image information within the divided rectangular area; a read/write control unit that reads image information in a rectangular area divided from the two-dimensional memory using addresses and stores image information that has undergone predetermined rotational conversion; and an image read out by the read/write control unit. and a vertical/horizontal conversion buffer that performs vertical/horizontal rotation conversion of information, and the image information subjected to vertical/horizontal rotation conversion by the vertical/horizontal conversion buffer is read/translated.
An image rotation processing method characterized in that the image is stored in a predetermined area of the two-dimensional memory by a write control unit.