Computer graphics processing and selective visual display system – Computer graphics processing – Three-dimension
Reexamination Certificate
1999-04-26
2003-05-13
Vo, Cliff N. (Department: 2671)
Computer graphics processing and selective visual display system
Computer graphics processing
Three-dimension
Reexamination Certificate
active
06563497
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an image processing apparatus, and particularly to an image processing apparatus which can easily generate a variety of signals as key signals used at mixing of images.
2. Description of the Related Art
FIG. 1
shows a structure of an example of a conventional video switcher as an image mixing system which mixes two images in accordance with a key signal and outputs a mixed image.
In this video switcher, a key signal which controls a ratio of mixing (transmittance of one image to the other image when the two images are mixed) for every pixel and has a value within the range of from 0 to 1, is generated, and images A and image B are mixed in accordance with the key signal.
That is, an input unit
1
includes a button, a dial, a lever and the like for specifying patterns and parameters of various wipes. When a user operates the button and the like for a pattern and parameter of a desired wipe, a signal corresponding to the operation is outputted to a controller
31
. When receiving the signal from the input unit
1
, the controller
31
controls a key signal generating unit
32
based on the signal, so that the key signal generating unit
32
is made to generate a key signal for executing the wipe. This key signal is supplied to a mixing unit (image mixing unit)
4
. The image mixing unit
4
is supplied with not only the key signal but also two images A and B as objects of mixing. When receiving the key signal from the key signal generating unit
32
, the image mixing unit
4
mixes the images A and B in accordance with the key signal and outputs a mixed image C obtained as the result of mixing.
FIG. 2
shows a structural example of the key signal generating unit
32
in the video switcher of FIG.
1
.
In
FIG. 2
, the key signal generating unit
32
is constituted by a command buffer
41
, a general-purpose CPU (Central Processing Unit)
42
, a program memory
43
, and a key signal storing memory
44
.
The command buffer
41
is supplied, from the controller
31
, with a command to the general-purpose CPU
42
and other data necessary for generating a key signal, and the command buffer
41
temporarily stores the command or the like from the controller
31
. The general-purpose CPU
42
reads the command stored in the command buffer
41
, and executes one of the programs stored in the program memory (internal ROM (Read Only Memory)
43
, which corresponds to the command read from the command buffer
41
. By this, the general-purpose CPU
42
generates a key signal, and stores the key signal corresponding to each pixel in the key signal storing memory
44
. The key signal storing memory
44
is composed of, for example, a dual-port memory with storage capacity corresponding to pixels of one screen, temporarily stores key signals for the respective pixels of one screen from the general-purpose CPU
42
, and supplies them to the mixing unit
4
. Incidentally, the program memory
43
can be made built in the general-purpose CPU
42
.
Next,
FIG. 3
shows a structural example of the controller
31
in the video switcher of FIG.
1
.
The controller
31
is mainly constituted by a CPU
51
and a program memory
52
. The CPU
51
executes a program stored in the program memory
52
in response to a signal from the input unit
1
, so that it performs a process for controlling the key signal generating unit
32
.
That is, the program memory
52
stores a key selecting program for carrying out a key selecting process. The CPU
51
executes the key selecting program in accordance with a signal from the input unit
1
, so that it performs the key selecting process for generating a key number (key No.) which identifies a shape pattern of a key signal to be generated by the key signal generating unit
32
, and for generating a parameter which specifies the state of the key signal (for example, size, position, etc. of the key signal) and the way of changing the key signal (rotation angle, amount of parallel movement, etc.). The CPU
51
supplies, as a command, the key number and parameter obtained as the result of the key selecting process to the key signal generating unit
32
.
The program memory
43
of the key signal generating unit
32
stores key signal generating programs for performing key signal generating processes. That is, the program memory
43
stores the key signal generating programs each generating a key signal of a shape pattern corresponding to each key number. When receiving a key number and parameter from the controller
31
, the CPU
42
of the key signal generating unit
32
executes the key signal generating program corresponding to the key number in accordance with the parameter from the controller
31
. By this, a key signal in which its shape pattern is specified by the key number and its state and way of changing are specified by the parameter, is generated and is stored in the key signal storing memory
44
.
Next, with reference to the flowchart of
FIG. 4
, the key selecting process executed by the CPU
51
of
FIG. 3
will be described further.
In the key selecting process, when the user operates the input unit
1
and a signal corresponding to the operation is supplied to the CPU
51
, at step S
31
, the CPU
51
determines the shape pattern of the key signal in accordance with the signal, and further, at step S
32
, determines the parameter for specifying the state of the key signal and the way of changing the key signal. Then, the CPU
51
proceeds to step S
33
, and transmits the key number, which corresponds to the shape pattern of the key signal determined at step S
31
, and the parameter determined at step S
32
to the key signal generating unit
32
. Next, the CPU waits for supply of a signal corresponding to operation of the user from the input unit
1
and returns to step S
31
.
Next, with reference to the flowchart of
FIG. 5
, the key signal generating process performed by the CPU
42
of
FIG. 3
(
FIG. 2
) will be further described.
In the key signal generating process, first of all, at step
41
, the CPU
42
receives the key number and the parameter transmitted from the controller
31
, proceeds to step S
42
, and reads out one (hereinafter, referred to suitably as individual pattern generating program) of the key signal generating programs stored in the program memory
43
which corresponds to the key number from the controller
31
. Further, at step S
42
, the CPU
42
executes the individual pattern generating program in accordance with the parameter from the controller
31
. By this, the CPU
42
generates such a key signal that its shape pattern is specified by the key number and its state and way of changing are specified by the parameter. The CPU
42
stores this key signal in the key signal storing memory
44
, and then, waits for a key number and parameter transmitted from the controller
31
and returns to step S
41
.
Next, with reference to
FIG. 6
, the process of the mixing unit
4
of
FIG. 1
will be described.
For example, in the key signal generating unit
32
, when a star-shaped key signal K is generated, and is inputted, together with images A and B, into the mixing unit
4
, the images A and B are mixed in the mixing unit
4
in accordance with the key signal K so that a mixed image C is formed.
Now, it is assumed that a pixel at an x-th position from the left of a screen and at a y-th position from the above is expressed by p(x, y), and pixel values of the images A, B, and C at the pixel p(x, y) are expressed by a(x, y), b (x, y), and c(x, y), respectively. Besides, it is assumed that a value of the key signal K at the pixel p(x, y) is expressed by k(x, y). When the key signal k(x, y) is expressed by, for example, 8 bits, in the mixing unit
4
, the pixel value c(x, y) of the image C is obtained in accordance with, for example, the following equation.
c
(
x, y
)=(
k
(
x, y
)
a
(
x, y
)+(255
−k
(
x, y
))
b
(
x, y
))/255 (1)
In the key signal K, the value k(x, y) of a white star-shaped portion corresponds to 255,
Bell Boyd & Lloyd LLC
Sony Corporation
Vo Cliff N.
LandOfFree
Image processing apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Image processing apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Image processing apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3062128