JPS6349887A - Image converter - Google Patents

Abstract

PURPOSE:To generate an effective image large in impact, to which a dummy shadow is added, by varying the luminance of an original image in accordance with a local reduction rate of a shape, and also, varying the luminance of the corresponding picture element in accordance with a picture element position coordinate value on a new image. CONSTITUTION:A conversion address generating device 11 outputs a picture element coordinate value 12 on a new image plane, a point coordinate value 13 on an original image plane corresponding to the coordinate value 12, and a local reduction rate 18 of an original image, in accordance with a three-dimensional geometrical structure expression, a coefficient, a position, a direction and a visual point position, and a screen position. A luminance converting part A1b performs an arithmetic operation in accordance with the local reduction rate, to an output of a two-dimensional adaptive filter 1a, and writes a luminance variation in an image memory 17. A luminance arithmetic part B1c derives a coefficient in accordance with a new image coordinate value which a read-out address control unit 15 has used in order to fetch a read-out address from a coordinate correspondence memory 14, and calculates the luminance by using these coefficients. A new image which is obtained goes to an image to which an artificial shadow is added when the light is projected from an oblique direction.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an image conversion device that can be used for image shape conversion in image special effects devices and the like.

BACKGROUND OF THE INVENTION In recent years, advances in image processing technology have made it possible to produce various special effects, and many special effects devices have been released. In these special effects devices, conversion operations are performed not only on image data but also on addresses.

A conventional image conversion device will be described below with reference to the drawings.

FIG. 3 shows a conventional image conversion device, where 31 is a conversion address generation device, 32 is a pixel coordinate value on the new image plane, 33 is a point coordinate value on the original image plane, 34 is a coordinate correspondence memory, and 35 is a coordinate value of a point on the original image plane. A read address control device, 36 a write address control device, 37 an image memory, 38 a local reduction rate of the original image, 39 a reduction rate memory, and 3a a two-dimensional adaptive filter.

The operation of the image conversion apparatus configured as described above will be explained below using FIG. 3.

First, the conversion address generation device 31 generates a given three-dimensional geometric structure expression, coefficient, position, direction and viewpoint position,
According to the screen position, the pixel coordinate value 32 on the new image plane
, a point coordinate value 33 on the original image plane corresponding to the pixel coordinate value 32 on the new image plane, and a local reduction rate 38 of the original image. The coordinate correspondence memory 34 stores the point coordinate value 33 on the original image plane using the pixel coordinate value 32 on the new image plane for address designation. The reduction ratio memory 39 stores the local reduction ratio 3)3 of the original image. The two-dimensional adaptive filter 3a removes high-frequency components while changing local filter characteristics according to the contents of the reduction ratio memory 39. The image memory 37 sequentially stores the original image from which high-frequency components have been removed by the two-dimensional adaptive filter under the control of the write address control device 36. Successive address control device 3
5 generates a parent image by reading the image data of the original image from the image memory 37 according to the coordinate values of points on the original image plane taken out from the coordinate correspondence memory 34 in accordance with the timing of the new image. For example, the Television Society Technical Report V
o1.9, ? h20. As described in PP0E62-9.

Problems to be Solved by the Invention However, the mapping shape generated by the above configuration cannot be recognized as a three-dimensional geometric shape by E'2 BFA on the new image unless it is rotated and translated. It had some problems.

SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to provide an image conversion device that can create an effect video with a large impact by adding shadows to a mapping shape.

Means for Solving the Problems In order to solve the above problems, the image conversion device of the present invention includes:
It is constructed by adding a brightness converter that can change the brightness according to the local reduction rate of the shape, and a brightness converter that can change the brightness information of the corresponding pixel according to the pixel position coordinate value on the new image. .

Effect The present invention uses the above-described configuration to change the brightness of the original image according to the local reduction rate of the shape, and further changes the brightness of the corresponding pixel according to the pixel position coordinate value on the new image, thereby applying light from an oblique direction. It is possible to add pseudo shadows to create a video with a great impact.

Embodiment Usually, in order to add shadows when mapping an original image to a three-dimensional shape, it is sufficient to increase or decrease brightness information in the pixel information of the original image depending on the direction of the shape surface. In the present invention, the increase in calculation load is minimized by using the local reduction rate of the shape and the pixel position coordinate value on the new image as the increase/decrease parameter of the brightness information, instead of using the above method. You can obtain a shadow effect by suppressing it.

An image conversion device according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a block diagram of an image conversion device in a first embodiment of the present invention.

In FIG. 1, 1b is a brightness converter A, IC is a brightness converter B, and the other parts are the same blocks as in FIG.

The operation of the image conversion apparatus configured as described above will be described below with reference to FIGS. 1 and 2.

First, the conversion address generation device 1j generates a given three-dimensional geometric structure expression, coefficients, position, direction and viewpoint position,
According to the screen position, the pixel coordinate value 12 on the new image plane
, a point coordinate value 13 on the original image plane corresponding to the pixel coordinate value 12 on the new image plane, and a local reduction rate 18 of the original image are output. The coordinate correspondence memo January 4 uses the pixel coordinate value 12 on the new image plane to specify the address and stores the coordinate value 13 of the point on the original image plane. The reduction rate memo January 9 stores the local reduction rate of 18 of the original image. 2D adaptive filter 1
In step a, high-frequency components are removed while changing local filter characteristics according to the contents of the reduction rate memo January 9. The brightness conversion unit Alb performs the calculations shown in the table below on the output of the two-dimensional adaptive filter 1a according to the local reduction rate, and writes the results into the image memory 17.

However, the small area image memo 1J17 of the original image sequentially stores the original image whose brightness has been manipulated according to the local reduction rate by the brightness converter Alb under the control of the write address control device 16.

The read address control device 15 reads the image data of the original image from the image memo January 7 according to the coordinate value of the point on the original image plane taken out from the coordinate correspondence memo January 4 in accordance with the timing of the new image. For example, the second
Find the coefficients Kx (x) and Ky (y) shown in the figure,
Using these coefficients, brightness Ys is calculated using the following equation.

Ys=Kx (x)*Ky (y)*Y The new image obtained by the above formula becomes an image with a pseudo shadow added according to the pixel position coordinate values on the new image.

The shadows produced by the brightness conversion device Alb and the brightness conversion device Blc are combined to add a pseudo shadow when light is applied from an oblique direction.

Effects of the Invention As described above, the present invention uses a brightness conversion coefficient that can change brightness according to the local reduction rate of a shape, and a brightness conversion coefficient that can change the brightness of a corresponding pixel according to the pixel position coordinate value on a new image. By having the luminance converting section B that can perform this function, it is possible to realize an image converting device that can add a pseudo shadow when light is applied from an oblique direction.

[Brief explanation of drawings]

FIG. 1 is a professional diagram of an image conversion device according to an embodiment of the present invention, FIG. 2 is a graphical representation of luminance conversion coefficients in an embodiment of the present invention, and FIG. 3 is a diagram of a conventional image conversion device. It is a block diagram. 11... Conversion address generation device, 12...
...Pixel coordinate value on new image plane, 13... Point coordinate value on original image plane, 14... Coordinate correspondence memory, 1
5... Read address control device, 16...
...Write address control device, 17... Image memory, 18... Local reduction rate of original image, 19
...Reduction ratio memory, 1a... Two-dimensional adaptive filter, 1b... Brightness conversion section A, IC.
... Brightness conversion unit 21 ... New image plane coordinate system, 22 ... Brightness conversion coefficient (X direction), 23.
...Brightness conversion coefficient (y direction). 31... Conversion address generation device, 32...
...Pixel coordinate value on new image plane, 33... Point coordinate value on original image plane, 34... Coordinate correspondence memory, 3
5... Read address control device, 36...
...Write address control device, 37... Image memory, 38... Local reduction rate of original image, 39
...Reduction rate memory, 3a... Two-dimensional adaptive filter.

Claims (1)

[Claims] A new image is generated by using the read address calculated according to the given three-dimensional geometric structure expression, coefficient, position, direction, viewpoint position, and screen position to read from the image memory, and the local shape of the shape is An image conversion device having a two-dimensional adaptive filter unit that can change filter characteristics according to a reduction rate, and a brightness conversion unit A that can change brightness according to the reduction rate;
An image conversion device comprising: a brightness conversion unit B capable of changing the brightness of a corresponding pixel according to a pixel position coordinate value on a new image.