JPH0337227B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an image rotation conversion device, and more particularly to an image rotation conversion device that executes 90° rotation conversion of image data in real time.

[Background of the invention]

Conventionally, when rotating an image, it is performed by performing a conversion process that rotates the image on the read address and write address for the image data in memory (for example, 53−3743
(See "Image conversion device" in the publication). however,
Rotation conversion of image data has the disadvantage that the range of image data in memory that can be rotated is limited by word boundaries because data read/write operations are performed using byte processing. ,
Furthermore, when the above drawbacks are removed, software processing such as register shift is performed, so as the image data to be rotationally transformed becomes larger in scale, the processing time for rotational transformation becomes longer.

[Purpose of the invention]

An object of the present invention is to eliminate such conventional drawbacks, to rotationally transform an arbitrary partial image without imposing word boundary constraints on image data in memory, and to store this rotationally transformed image in memory. An object of the present invention is to provide an image rotation conversion device that can transfer an image to an arbitrary position within the image.

[Summary of the invention]

In order to achieve the above object, the image rotation conversion device of the present invention rotates image data in memory to the right or left.
A device for rotation conversion to 90 degrees includes a storage means for storing n×m (multiple of n=16, m1) of the above image data, and read/write to the storage means using a serial signal to convert the image data. A rotation conversion means for rotating data by 90 degrees, and a DMA for rotation conversion of all arbitrary rectangular partial images of the image data by performing DMA transfer of image data to the memory according to the request of the rotation conversion means. It is characterized by having means.

[Embodiments of the invention]

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

FIG. 1 is a block diagram of an image rotation conversion apparatus showing an embodiment of the present invention.

In FIG. 1, 1 is an image information storage memory, 2
is DMAC (Direct Memory Access Controller),
3 is a rotation conversion circuit, 4 is an address bus, 5 is a data bus, 6 is a rotation conversion start signal, 7 is a shift control parameter, 8 is a read/write request signal,
9 is a processing start signal.

When the DMAC 2 receives the activation signal 9 from the host device, it takes in the rectangular partial image data from the image information storage memory 1, and sets the start address of the partial image,
After calculating the shift control parameters and the number of 16×16 dot blocks, a rotation conversion start signal 6 is sent to the rotation conversion circuit 3 to execute 90° rotation conversion.
When a read/write request signal 8 is received from the rotation conversion circuit 3, read/write access processing, image data address management, 16×16 dot block management, etc. are performed in the image information storage memory 1. The image conversion circuit 3 receives the above-mentioned rotational conversion start signal 6, and performs 90° rotational conversion of the image data using the configuration shown in FIG.

In FIG. 2, 10 and 12 are buffers for parallel to serial (P→S) conversion of the source image data and destination old image data, respectively, and 11 and 23 are source image data and destination old image data, respectively. Lead buffers 13 and 14 are X and Y, respectively.
15 is a RAM for rotating 256 dots (16 x 16 bits), 16 is a selector for selecting the transfer source image data or the transfer destination old image data, and 17 is the transfer destination new image data serial → parallel ( S→P) conversion buffer, 18 is a buffer for writing new image data at the destination, 19 is a clock control unit, 20 is a source image system block, 21 is a rotation conversion system block, and 22 is a destination image system block. . The transfer source image data, the transfer destination old image data, and the transfer destination new image data are all image data in the image information storage memory 1, and the image data of the area to be rotated by 90 degrees and the image data of the area to be rotated by 90 degrees, respectively. In other words, it refers to image data of an area that is unnecessary, that is, can be converted into new data without changing its state, or newly created image data.

The above-mentioned transfer source image data is sent from the image information storage memory 1 to the read buffer 23 through the 16-bit data bus 5, and then the transfer source image system block 20 receives a command from the clock control section 19 to switch from P to S. Conversion is performed, and the buffer for P→S conversion is 10
The data is sent to the RAM 15 through the Further, the serial source image data is written into the RAM 15 as shown in FIG. 3A while the rotation conversion system block 21 counts the X-coordinate counter 13 and the Y-coordinate counter 14. In that case, the X-coordinate counter 13 is caused to repeatedly count 0 to 15 for the X-direction address 25,
One Y-coordinate counter 14 is incremented by "1" when the count value of the X-coordinate counter 13 returns to "0" for the Y-direction address 24, and both count values are set to "15" ( 16×16=
The write operation continues until 256 dots are displayed.

In addition, when reading the transfer source image data from the RAM 15, as shown in FIG.
~15 is repeatedly counted, and one X-coordinate counter 13 has the following values for the X-direction address 25:
By counting up "1" when the count value of the Y-coordinate counter 14 returns to "0", the serial image data obtained by rotating the image data written above by 90 degrees is passed through the selector 16 and sent to S. →Sent to P conversion buffer. Furthermore, the serial image data is processed by a clock control section 19.
In response to this command, the destination image system block 22 performs S→P conversion, and the write buffer 18 and data bus 5
The image data is sent to the image information storage memory 1 through the image information storage memory 1, and becomes the new image data to be transferred. As before, transmission continues until both count values indicate "15".

Note that the above write/read operations are performed in synchronization with the DMAC2. Furthermore, the above is a case of rotation by 90 degrees to the right, but when rotating by 90 degrees to the left, the initial value of the X-coordinate counter 13 in the read operation is set to "15",
Do it with a down count.

On the other hand, the transfer destination old image data is sent from the image information storage memory 1 to the read buffer 11 through the 16-bit data bus 5, and then, in the same way as the write operation of the transfer source image data, P→ The signal is S-converted and sent to the selector 16 through the P→S conversion buffer 12. If it is selected by the selector 16, the same transfer destination image system block 22 performs S→P conversion and sends it to the image information storage memory 1 to become the new transfer destination image data.

The clock control unit 19 receives the rotation conversion start signal 6 and the shift control parameter 7 from the DMAC 2, and sends a shift command to each of the transfer source image system block 20, rotation conversion system block 21, and destination image system block 22, and sends a shift command to the selector. A switching signal is output to the DMAC 16, and a read/write request signal 8 corresponding to the shift status of each block is sent back to the DMAC 2.

FIG. 4 is an operation flowchart of the DMAC 2, and FIG. 5 is a diagram for explaining the method of managing a 16×16 dot block by the DMAC.

When the DMAC 2 receives the activation signal 9 from the host device (step 101), it first reads the information parameters of the rectangular partial image area from the image information storage memory 1 (step 102), and determines the direction of rotational conversion (step 103). ~105), calculate the top addresses of the transfer source and the transfer destination (step 106), and convert the rectangular partial image data into 16
Divide the block into ×16 dots (step
107).

Furthermore, the calculated shift control parameter 7 is sent to the clock control section 19 (steps 108 and 109),
Next, the rotation conversion start signal 6 is sent out (step 110), and the 90° rotation conversion process (REQ, SEL, JUMP routine shown in FIG. 4), which also operates the rotation conversion circuit 3, is started (step 111). .

That is, the read/write from the clock control section 19
When the write request signal 8 is received, first, the transfer destination image system block 22 takes in the transfer destination old image data by DMA transfer (step 113), and creates the transfer destination new image data (step 114). Next, the transfer source image system block 20 takes in, for example, the block shown in FIG. 5A from the transfer source image data (step 112), and creates new transfer destination image data (step 114). Steps 112 and 114 are repeated as blocks, and the process ends when the last block is processed (steps 115 and 117). Also,
Next, to switch the 16×16 dot unit block to be read or written, the start address is determined based on the received read/write request signal 8 and the shift control parameter 7 calculated above (step 116). Since the data is read in the block order shown in Figure a and written in the block order shown in Figure b, it is possible to create a new image rotated 90 degrees to the right.

In this way, by receiving the rotation conversion start signal 6 and the shift control parameter 7, the image data is shifted while the read/write request signal 8 is returned, and 16
The rotation conversion circuit 3 performs rotation conversion in units of ×16 dot blocks, and the DMA data transfer operation is performed in real time in response to the read/write request signal 8 sent back to manage the address of the image data area and convert the image data. Also handles block management
Since it operates in parallel with DMAC2, it is efficient.
90° rotation conversion processing is possible.

〔Effect of the invention〕

As explained above, according to the present invention, the rotation conversion circuit that performs rotation conversion of image data and the DMAC that performs DMA transfer, address and block management of image data are operated in parallel to perform 90° rotation conversion. 90° rotation transformation of a rectangular partial image can be accelerated without imposing word boundary restrictions on image data in memory.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the configuration of an image rotation conversion device showing an embodiment of the present invention, FIG. 2 is a configuration diagram of an image conversion circuit, and FIGS. 3a and 3b are for explaining the rotation conversion operation by the image conversion circuit. Figure 4 is DMAC
Operation flowchart, Figure 5 a and b are DMAC
FIG. 1: Image information storage memory, 2: DMAC, 3:
Rotation conversion circuit, 4: Address bus, 5: Data bus, 6: Rotation conversion start signal, 7: Shift control parameter, 8: Read/write request signal,
9: Start signal, 10, 12: P-S conversion buffer, 11, 23: Read buffer, 13: X coordinate counter, 14: Y coordinate counter, 15:
RAM, 16: Selector, 17: S-P conversion buffer, 18: Write buffer, 19: Clock control unit, 20: Source image system block, 21:
Rotation conversion system block, 22: Transfer destination image system block, 24: Y direction address, 25: X direction address.

Claims (1)

[Claims] 1 An image rotation conversion device that rotationally transforms arbitrary partial image data in an image memory and then transfers the image data to an arbitrary position in the image memory, wherein a predetermined unit of image data containing the image data to be rotationally transformed is transferred from the image memory to an arbitrary position in the image memory. a first reading means for reading image data and a predetermined unit of image data including image data of a transfer destination area to which the image data after rotational conversion is transferred;
a first memory for storing a predetermined unit of image data including the image data to be rotationally converted read out by the first reading means; a second memory for storing a predetermined unit of image data including image data of a destination area to which the image data is transferred; and serially reading image data stored in the first memory and the second memory. a second reading means; and selecting image data read out from the first memory by the second reading means in a direction different from the storage direction and image data read out from the second memory. An image rotation conversion device characterized in that it comprises means for transmitting images to said image memory.