Television – Camera – system and detail – With single image scanning device supplying plural color...
Reexamination Certificate
1995-06-06
2001-08-28
Miller, John W. (Department: 2611)
Television
Camera, system and detail
With single image scanning device supplying plural color...
C348S279000, C348S228100, C348S659000
Reexamination Certificate
active
06281932
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an image pickup apparatus using a solid state image pickup device.
2. Related Background Art
A single plate color camera has, for example, color filters and a single solid state image pickup device to form an image through each color filter. The color filters for transmitting different color lights are sequentially arranged on photosensitive elements on the solid state image pickup device, an object image is formed on the solid state image pickup device, and chrominance signals and a luminance signal which have been space modulated are obtained from the solid state image pickup device.
In such a color camera, there is a color camera which obtains chrominance signals from an image pickup device having a color filter arrangement as shown in
FIG. 1
by executing the following processes.
In the image pickup device, a video signal is generated by performing the following scan. In even number fields, the charges of the photosensitive elements of the n-th and (n+1)th horizontal lines which are neighboring in the vertical direction and the charges of the photosensitive elements of the (n+2)th and (n+3)th horizontal lines are respectively added and transferred. In the odd number fields, the charges of the photosensitive elements of the (n+1)th and (n+2)th horizontal lines which are neighboring in the vertical direction and the charges of the photo sensitive elements of the (n+3)th and (n+4)th horizontal lines are respectively added and transferred and outputted. By such scans, signals constructed by the following primary color chrominance signal component ratios are outputted.
n-th line of the even number fields:
on the mth column, Mg+Cy=R+G+2B;WB
on the (m+1)th column, G+Ye=R+2G;GR
(n+2)th line of the even number field:
on the m-th column, G+Cy=2G+B;GB
on the (m+1)th column, Mg+Ye=2R+G+B;WR
(n+1)th line of the odd number field:
on the m-th column, Cy+G=2G+B;GB
on the (m+1)th column, Ye+Mg=2R+G+B;WR
(n+3)th line of the odd number field:
on the m-th column, Cy+Mg=R+G+2B ;WB
on the (m+1)th column, Ye+G=R+2G;GR
A matrix including four predetermined numbers is multiplied to such four kinds of signals WB, WR, GR, and GB, thereby extracting the primary color component of one of three primary colors R, G, and B. Therefore, primary color signals of red (R), green (G), and blue (B) are obtained by, for example, executing arithmetic operating processes based on the following numerical expression (1).
(
R
G
B
)
=
(
x
0
,
x
1
,
x
2
,
x
3
y
0
,
y
1
,
y
2
,
y
3
z
0
,
z
1
,
z
2
,
z
3
)
*
(
WB
WR
GR
GB
)
(
1
)
That is, R is obtained by respectively multiplying x
0
, x
1
, x
2
, and x
3
to the four kinds of signals WB, WR, GR, and GB. G is obtained by respectively multiplying y
0
, y
1
, y
2
, and y
3
to the four kinds of signals WB, WR, GR, and GB. B is obtained by respectively multiplying z
0
, z
1
, z
2
, and z
3
to the four kinds of signals WB, WR, GR, and GB.
Since the above four kinds of signals are output by the above scanning method in a time-division manner, they are not simultaneously derived. Therefore, it is constructed so that the same kind of signals can be always derived by delay elements of one horizontal line and one pixel and a selecting circuit.
In the single plate image pickup device, however, a luminance signal component is also separated from the four kinds of chrominance signal components obtained from the image pickup device. Actual color transmitting characteristics of color filters Mg, Ye, Cy, and G in
FIG. 1
exhibit RGB transmitting characteristics which are different from those mentioned above. There is a drawback such that the RGB signals obtained by performing color separating processes or demodulating processes don't show good color separating characteristics.
On the other hand, since the RGB primary color components are directly obtained from the output of the image pickup device, there is a drawback such that the hue cannot be easily adjusted as it is demanded.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an image pickup apparatus which can solve the drawbacks in the conventional techniques as mentioned above.
Another object of the invention is to provide an image pickup apparatus which can obtain a color separation matrix of good color separating characteristics from image pickup signal data of an object whose color is to be separated and can separate the color.
According to a preferred embodiment of the present invention, there is provided an image pickup apparatus having a single solid state image pickup device for forming an image input through an individual color filter, wherein the apparatus has color separating means for executing arithmetic operating processes to output signals of the image pickup device corresponding to the lights of different colors, thereby obtaining primary color components. Color filters for transmitting the lights of different colors are sequentially arranged on photosensitive elements on the solid state image pickup device, an object image is formed on the solid state image pickup device, and chrominance signals and a luminance signal which have been space modulated are obtained from the solid state image pickup device. The image pickup apparatus obtains arithmetic operation coefficients of the color separating means from the image pickup output signal of the image pickup device.
According to the embodiment of the invention as mentioned above, in consideration of the primary color component compositions of an object, a color separation matrix is approximated from the image pickup signal data of the object which color is to be separated to a complementary color or a pure color, so that a color separation matrix of good color separating characteristics or a color separation matrix in which other color components are not mixed is obtained.
According to another embodiment, by multiplying hue adjustment coefficients to the primary color component compositions of an object, a color separation matrix is approximated from the image pickup signal data of the object whose color is to be separated to a complementary color, hue adjustment coefficients are multiplexed in the complementary color space, and the color separation matrix is approximated, thereby constructing a color separation matrix having desired color separating characteristics.
According to still another embodiment, the image pickup signal data of an object whose color is to be separated to a: pure color is mapped to a complementary color system space, hue adjustment coefficients are multiplied in the complementary color system space to the image pickup signal data, and the data is again mapped into an RGB primary color space, thereby approximating a color separation matrix.
The above and other objects and features of the present invention will become apparent from the following detailed description and the appended claims with reference to the accompanying drawings.
REFERENCES:
patent: 5121193 (1992-06-01), Nishimura et al.
patent: 5134465 (1992-07-01), Ohki et al.
patent: 5170249 (1992-12-01), Ohtsubo et al.
patent: 5260774 (1993-11-01), Takayama
patent: 2165790 (1990-06-01), None
Fukatsu Tsutomu
Shimokoriyama Makoto
Canon Kabushiki Kaisha
Miller John W.
Morgan & Finnegan L.L.P.
LandOfFree
Image pickup apparatus having a complementary... 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 pickup apparatus having a complementary..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Image pickup apparatus having a complementary... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2475010