The optimal morphology that carries out an invention
Describe with regard to embodiments of the invention below
The 1st embodiment
Below just describe corresponding to the 1st embodiment of claim 1 of the present invention, claim 2.
Fig. 1 (a) illustrates the solid-state color imager according to the 1st embodiment of the present invention.In the drawings, the 1st, realize making reference object imaging on the solid-state imager surface, be the optical system that constitutes by lens etc.The 2nd, realize the reference object picture (optical image) of imaging is transformed into picture signal (electric signal), constitute by the solid-state imager that has color separation filter.The 3rd, realize constituting by AD converter become data image signal from the resulting image signal transformation of solid-state imager.The 4th, realize constituting by imaging signal processing circuit be transformed into luminance signal and color difference signal from the resulting data image signal of AD converter.
Fig. 1 (b) illustrates the color separation filter of the solid-state imager on the surface that attaches the solid-state imager 2 in Fig. 1 (a), expression is by the pattern of an example of vertical two pixels, horizontal two pixels repetition, the configuration of filter is the panchromatic transmission filter from a left side, dark green transmission filter by two pixels in top, and following two pixels are that the yellow transmission filter from a left side, panchromatic transmission filter constitute.
Fig. 3 (a) illustrates this 1st embodiment's, the input/output signal of the imaging signal processing circuit 4 among Fig. 1 (a).
In Fig. 1 (a), make reference object imaging on the solid-state imager surface via optical system 1, by the solid-state imager 2 that has color separation filter the reference object picture (optical image) of imaging is transformed into picture signal (electric signal), becoming data image signal, be transformed into luminance signal and color difference signal from the resulting data image signal of AD converter by AD converter 3 by 4 of imaging signal processing circuits from the resulting image signal transformation of solid-state imager.And then, attaching in the arrangement of the color separation filter of solid-state imager 2 is the formation of the pattern of vertical two pixels of repetition, horizontal two pixels as shown in Fig. 1 (b), the filter of this pattern, two pixels in top are the panchromatic transmission filter from a left side, dark green transmission filter, following two pixels are the yellow transmission filter from a left side, panchromatic transmission filter, make in four pixels two and have panchromatic transmission filter, two other pixel is the formation of dark green transmission filter, yellow transmission filter.Become four of the totals of two full-color information, a dark green information, a yellow information this moment from the resulting picture signal of solid-state imager, carry out matrix computations to these four, from four luminance signals of imaging signal processing circuit 4 outputs, a R-Y color difference signal, a B-Y color difference signal.
Describe with regard to the conversion action in the imaging signal processing circuit 4 below with reference to Fig. 3 (a) to luminance signal, color difference signal.
If represent the primary components (red, green, blue, as to be respectively R, G, B) of light then to be generally W=R+G+B, Cy=G+B, Ye=R+G with each transmission filter.Luminance information constitutes by R, G, B institute is important, is only made by the signal from panchromatic transmission filter that becomes pure sample information about the luminance signal Y of the position of panchromatic transmission filter, is approximately
Y(h,v)=a×W(h,v)
In the formula, a adjusts the coefficient that dynamic range is used, and h+v is always even number in the example of Fig. 3 (a).
Luminance signal Y about the position that do not have panchromatic transmission filter also uses the information of location about to make in addition, as simple creating method, is approximately
Y(h,v)=a×((W(h-1,v)+W(h+1,v)+W(h,v-1)+W(h,v+1))÷4)
In the formula, a adjusts the coefficient that dynamic range is used, and h+v is always odd number in the example of Fig. 3 (a).
Perhaps, generate colour information, if the luminance signal Y of the position of dark green filter then because Cy does not have the R component in the luminance signal component, so come interpolation according to surrounding pixel, is approximately as the correct position of pure sample information
R(h,v)=a×(W(h-1,v)+W(h+1,v)+W(h,v-1)+W(h,v+1))÷4
-b×(Cy(h,v)×4+Cy(h-2,v)+Cy(h+2,v)+Cy(h,v-2)+Cy(h,v+2))÷8
Y(h,v)=b×Cy(h,v)+R(h,v)
If the luminance signal Y of the position of yellow filter then because Ye does not have the B component in the luminance signal component, so come interpolation according to surrounding pixel, is approximately
B(h,v)=a×(W(h-1,v)+W(h+1,v)+W(h,v-1)+W(h,v+1))÷4
-c×(Ye(h,v)×4+Ye(h-2,v)+Ye(h+2,v)+Ye(h,v-2)+Ye(h,v+2))÷8
Y(h,v)=c×Ye(h,v)+B(h,v)
In the formula, b, c adjust the coefficient that dynamic range is used, and h+v is always odd number in the example of Fig. 3 (a), and the h of the position of dark green filter is an odd number, and v is an even number, and the h of the position of yellow filter is an even number, and v is an odd number.
According to the luminance signal Y that Cy pixel and Ye pixel are obtained, the interpolation of R and the B component information by utilizing surrounding pixel makes, and is not to obtain according to the pure sample information that solid-state imager causes., with regard to Cy pixel G+B component, remain as pure sample information with regard to Ye pixel R+G component, the R and the B component of institute's interpolation are 1/3rd to the maximum in luminance signal Y, influence very for a short time, become the luminance signal Y that keeps the high-resolution state.
In addition, (R-Y B-Y), takes out each information of one about four luminance signals, is a pattern with vertical two pixels of luminance signal, horizontal two pixels, uses simple computational methods, at first is transformed into R, G, B with regard to color difference signal.The R that the color difference signal conversion is used, B component are
R(h,v)=a×W((h?div?2)*2,(v?div?2)*2)-b×Cy((h?div?2)*2+1,(v?div?2)*2)
B(h,v)=a×W((h?div?2)*2+1,(v?div?2)*2+1)-c×Ye((h?div?2)*2,(v?div?2)*2+1)
And then G becomes
G(h,v)=a×(W((h?div?2)*2,(v?div?2)*2)+W((h?div?2)*2+1,(v?div?2)*2+1))
÷2-R(h,v)-B(h,v)
According to this RGB, color difference signal is approximately approx
R-Y(h,v)=2×R(h,v)-G(h,v)
B-Y(h,v)=2×B(h,v)-G(h,v)
In the formula, a, b, c adjust the coefficient that dynamic range is used, and div represents only to take out the merchant of division arithmetic of integer and the calculating of casting out remainder, and * represents multiplying.
The a pair of color difference signal that obtains like this is not because repeat the output of solid-state imager and conversion for other color difference signal of adjacency, so the colour resolution raising.
By carrying out above computing, as shown in Fig. 3 (a), become four luminance signal Y for vertical two pixels, horizontal two pixels, obtain each two kinds of color difference signal R-Y, B-Y, just obtain as shown in Fig. 3 (a), be suitable for the form of conduct to the input signal of the element of 4: 2: 0 forms.
Moreover, except above-mentioned, set 0.3 for about R by transmissivity panchromatic transmission filter, set 0.59 for about B, set 0.11 ratio for about G, so obtain pure luminance signal because the ratio of the transmissivity of this panchromatic transmission filter equals the primary colors mixing ratio of luminance signal Y, can further improve resolution.If though that is to say usually and represent then to become W=R+G+B by each transmission filter with primary components (red, green, blue is respectively R, G, B), Cy=G+B, Ye=R+G, if but carry out above-mentioned setting, then the RGB mixing ratio of luminance signal Y just is expressed as
Y=0.30R+0.59G+0.11B
Each transmission filter of using in this 1st embodiment is adjusted transmissivity, becomes
W=0.30R+0.59G+0.11B
Cy=(0.59G+0.11B)÷0.7
Ye=(0.30R+0.59G)÷0.89
At this moment, the luminance signal Y with regard to the position of panchromatic transmission filter is only made by the signal from panchromatic transmission filter that becomes pure sample information, becomes
Y(h,v)=a×W(h,v)
In the formula, a adjusts the coefficient that dynamic range is used, and h+v is always even number in the example of Fig. 3 (a).With regard to the luminance signal Y of the position that do not have panchromatic transmission filter, also use the information of location about to make in addition,, become as simple creating method
Y(h,v)=a×((W(h-1,v)+W(h+1,v)+W(h,v-1)+W(h,v+1))÷4)
Perhaps, generate colour information, if the luminance signal Y of the position of dark green filter then also can become as the correct position of pure sample information
Y(h,v)=a×((W(h-1,v)+W(h+1,v)+W(h,v-1)+W(h,v+1))÷4)+0.7×b×(Cy(h-2,v)÷2-(Cy(h+2,v)+Cy(h,v-2)+Cy(h,v+2)+Cy(h,v))÷8)
If the luminance signal Y of the position of yellow filter then also can become
Y(h,v)=a×((W(h-1,v)+W(h+1,v)+W(h,v-1)+W(h,v+1))÷4)+0.7×c×(Ye(h-2,v)÷2-(Ye(h+2,v)+Ye(h,v-2)+Ye(h,v+2)+Ye(h,v))÷8)
In the formula, b, c adjust the coefficient that dynamic range is used, and h+v is always odd number in the example of Fig. 3 (a), and the h of the position of dark green filter is an odd number, and v is an even number, and the h of the position of yellow filter is an even number, and v is an odd number.
In addition, with regard to color difference signal (R-Y, B-Y), taking out each information of one about four luminance signals, is a pattern with vertical two pixels of luminance signal, horizontal two pixels, uses simple computational methods, becomes
R-Y(h,v)=0.7÷0.3×(a×(W((h?div?2)*2,(v?div?2)*2)+W((h?div?2)*2+1,(vdiv?2)*2+1))÷2-b×Cy((h?div?2)*2+1,(v?div?2)*2))
B-Y(h,v)=0.89÷0.11×(a×(W((h?div?2)*2,(v?div?2)*2)+W((h?div?2)*2+1,(vdiv?2)*2+1))+2-b×Ye((h?div?2)*2,(v?div?2)*2+1))
Perhaps, consider the sampling location of color difference signal, also can become
R-Y(h,v)=0.7+0.3×(a×(W((h?div?2)*2,(v?div?2)*2)+W((h?div?2)*2+1,(vdiv?2)*2+1))÷2-b×(Cy((h?div?2)*2+1,(v?div?2)*2)×2+Cy((h?div?2)*2-1,(vdiv?2)*2)+Cy((h?div?2)*2+1,(v?div?2)*2+2))÷4)
B-Y(h,v)=0.89÷0.11×(a×(W((h?div?2)*2,(v?div?2)*2)+W((h?div?2)*2+1,(vdiv?2)*2+1))÷2-b×(Ye((h?div?2)*2,(v?div?2)*2+1)×2+Ye((h?div?2)*2,(vdiv?2)*2-1)+Ye((h?div?2)*2+2,(v?div?2)*2+1))÷4)
Though in addition in above-mentioned the 1st embodiment, the configuration settings of PV filter becomes alternate configuration, but also can be taken as panchromatic transmission filter to two pixels in top in the repeat pattern of vertical two pixels, horizontal two pixels like that by image pattern 4 (a), following two pixels are taken as dark green transmission filter, yellow transmission filter, panchromatic transmission filter is configuration continuously laterally, as advantage horizontal resolution is improved.And then, the configuration of PV filter also can image pattern 4 (b) like that two pixels in top in the repeat pattern of vertical two pixels, horizontal two pixels have the repeat pattern of panchromatic transmission filter, dark green transmission filter from a left side, following two pixels are taken as panchromatic transmission filter, yellow transmission filter from a left side, panchromatic transmission filter is configuration continuously vertically, obtains the effect that vertical resolution improves as advantage.In addition the pattern of above-mentioned four pixels is taken as the structure that each pattern is all changed, also can obtains same resolution.
And then, though in above-mentioned the 1st embodiment, describe at the occasion of carrying out output in 4: 2: 0, though colour resolution descends when the color difference signal conversion, but owing to can dispose R, G, B component in any position by the mode of utilizing surrounding pixel, so not only this 1: 2: 0 output, and carried out 4: 4: 4,4: 2: 2, output in 4: 1: 1 also was possible.
In addition, though in above-mentioned the 1st embodiment, except panchromatic transmission filter, adopt dark green transmission filter and yellow transmission filter, also can beyond this panchromatic transmission filter, adopt red transmission filter, blue transmission filter.Advantage is to there is no need to take out R component and B component from filter, can simplify calculating.Shortcoming be because in Red lightscreening plate, blue color filter, do not comprise green component G die into the G component also replenish from surrounding pixel, so the just reduction of the resolution of luminance information.
In addition, though in the explanation in above-mentioned the 1st embodiment, vertical two pixels have been described, two pixels in the color separation filter top of horizontal two pixels are by the panchromatic transmission filter from a left side, dark green transmission filter, following two pixels are by the yellow transmission filter from a left side, the example that panchromatic transmission filter constitutes, but remain untouched and the person that changes the arrangement mode with regard to other the transmit color of filter, perhaps two panchromatic transmission filters remain untouched and change over the transmit color of dark green and yellow transmission filter dark green and magenta, or magenta and yellow, perhaps red and blue, or it is red and green, or green and blue formation, can implement equally.
The 2nd embodiment
Below just describe corresponding to the 2nd embodiment of claim 1 of the present invention, claim 3.
Fig. 1 (c) illustrates the color separation filter of the solid colorful imaging apparatus on the surface that attaches the solid-state imager 2 in Fig. 1 (a), expression is with a vertical pixel, the pattern of the example that horizontal four pixels repeat, the configuration of filter constitutes from a left side by panchromatic transmission filter, dark green transmission filter, panchromatic transmission filter, yellow transmission filter.
Fig. 3 (b) illustrates the input/output signal of the imaging signal processing circuit 4 of the Fig. 1 (a) among this 2nd embodiment.
In Fig. 1 (a), make reference object imaging on the solid-state imager surface via optical system 1, by the solid-state imager 2 that has color separation filter the reference object picture (optical image) of imaging is transformed into picture signal (electric signal), becoming data image signal, be transformed into luminance signal and color difference signal from the resulting data image signal of AD converter by AD converter 3 by 4 of imaging signal processing circuits from the resulting image signal transformation of solid-state imager.And then, attaching in the arrangement of the color separation filter of solid-state imager 2 is the formation of the pattern of the vertical pixel of repetition, horizontal four pixels as shown in Fig. 1 (c), the filter of this pattern, be the panchromatic transmission filter from a left side, dark green transmission filter, panchromatic transmission filter, yellow transmission filter, make in four pixels two and have panchromatic transmission filter, two other pixel is the formation of dark green transmission filter, yellow transmission filter.Become four of the totals of two full-color information, a dark green information, a yellow information this moment from the resulting picture signal of solid-state imager, carry out matrix computations to these four, from four luminance signals of imaging signal processing circuit 4 outputs, a R-Y color difference signal, a B-Y color difference signal.
Describe with regard to the conversion action in the imaging signal processing circuit below with reference to Fig. 3 (b) to luminance signal, color difference signal.
If represent the primary components (red, green, blue, as to be respectively R, G, B) of light then to be generally W=R+G+B, Cy=G+B, Ye=R+G with each transmission filter.Luminance information constitutes by R, G, B institute is important, is only made by the signal from panchromatic transmission filter that becomes pure sample information about the luminance signal Y of the position of panchromatic transmission filter, is approximately
Y(h,v)=a×W(h,v)
In the formula, a adjusts the coefficient that dynamic range is used, and h is always even number in the example of Fig. 3 (b).
Luminance signal Y about the position that do not have panchromatic transmission filter also uses the information of location about to make in addition, as simple creating method, be approximately Y (h, v)=a * ((W (and h-1, v)+W (h+1, v)) ÷ 2)
In the formula, a adjusts the coefficient that dynamic range is used, and h is always odd number in the example of Fig. 3 (b).
Perhaps, generate colour information, if the luminance signal Y of the position of dark green filter then because Cy does not have the R component in the luminance signal component, so come interpolation according to surrounding pixel, is approximately as the correct position of pure sample information
R(h,v)=a×((W(h-1,v)+W(h+1,v))×2+W(h-1,v-1)+W(h+1,v-1)+W(h-1,v+1)+W(h+1,v+1))÷8-b×(Cy(h,v)×2+Cy(h,v-1)+Cy(h,v+1))÷4Y(h,v)=b×Cy(h,v)+R(h,v)
If the luminance signal Y of the position of yellow filter then because Ye does not have the B component in the luminance signal component, so come interpolation according to surrounding pixel, also can be approximated to be
B(h,v)=a×((W(h-1,v)+W(h+1,v))×2+W(h-1,v-1)+W(h+1,v-1)+W(h-1,v+1)+W(h+1,v+1))÷8-c×(Ye(h,v)×2+Ye(h,v-1)+Ye(h,v+1))÷4Y(h,v)=c×Ye(h,v)+B(h,v)
In the formula, b, c adjust the coefficient that dynamic range is used, as make that mod is the calculating of remainder of only taking out the division arithmetic of integer, and then the h of the position of dark green filter is (hmod 4)=1, and the h of the position of yellow filter is (h mod 4)=3.
Obtain required R and B component when the above-mentioned luminance signal Y according to Cy pixel and Ye pixel, the interpolation of the information by utilizing surrounding pixel makes, thereby above-mentioned luminance signal Y obtains according to the pure sample information that solid-state imager causes., with regard to Cy pixel G+B component, remain as pure sample information with regard to Ye pixel R+G component, the R and the B component of institute's interpolation are 1/3rd to the maximum in luminance signal Y, influence very for a short time, become the luminance signal Y that keeps the high-resolution state.
In addition, (R-Y B-Y), takes out each information of one about four luminance signals, is a pattern with vertical pixel of luminance signal, horizontal four pixels, uses simple computational methods, at first is transformed into R, G, B with regard to color difference signal.The R that the color difference signal conversion is used, B component are
R(h,v)=a×W((h?div?4)*4,v)-b×Cy((h?div?4)*4+1,v)
B(h,v)=a×W((h?div?4)*4+2,v)-c×Ye((h?div?4)*4+3,v)
And then G becomes
G(h,v)=a×(W((h?div?4)*4,v)+W((h?div?4)*4+2,v))÷2-R(h,v)-B(h,v)
According to this RGB, color difference signal is approximately approx
R-Y(h,v)=2×R(h,v)-G(h,v)
B-Y(h,v)=2×B(h,v)-G(h,v)
In the formula, a, b, c adjust the coefficient that dynamic range is used.
The a pair of color difference signal that obtains like this because for other color difference signals of adjacency do not repeat the output of solid-state imager and conversion so colour resolution improve.
By carrying out above computing, as shown in Fig. 3 (b), become four luminance signal Y for a vertical pixel, horizontal four pixels, obtain each two kinds of color difference signal R-Y, B-Y, just obtain as shown in Fig. 3 (b), be suitable for the form of conduct to the input signal of the element of 4: 1: 1 forms.
Moreover, except above-mentioned, set 0.3 for about R by transmissivity panchromatic transmission filter, set 0.59 for about B, set 0.11 ratio for about G, so obtain pure luminance signal because the ratio of the transmissivity of this panchromatic transmission filter equals the primary colors mixing ratio of luminance signal Y, can further improve resolution.Can calculate with changing same method about this point with the 1st embodiment matrix.
In addition, same with above-mentioned the 1st embodiment, though colour resolution descends when the color difference signal conversion, but owing to can dispose R, G, B component in any position by the mode of utilizing surrounding pixel, so not only this 1: 1: 1 output, and carried out 4: 4: 4,4: 2: 2, output in 4: 2: 0 also was possible.
Moreover, the configuration of PV filter, different with the configuration of Fig. 1 (c), Fig. 3 (a), as shown in Fig. 5 (a), when the repetition longitudinally of the repeat pattern of a vertical pixel, horizontal four pixels the transmission filter pixel that staggers successively, configuration panchromatic transmission filter is made alternate shape can improve the resolution of the inclination of luminance signal whereby.And then, as shown in Fig. 5 (b), the configuration of the transmission filter beyond panchromatic is changed the panchromatic transmission filter of Fig. 1 (c), and make the repeated configuration of the pattern of eight pixels of replacing dark green and yellow transmission filter, can realize 4: 1: 1 modes whereby corresponding to a vertical pixel, horizontal four pixels, two sides' of 4: 2: 0 modes of vertical two pixels, horizontal two pixels, the filter configuration of chromatic colour resolution.
In addition, though in the explanation in the 2nd embodiment, a vertical pixel has been described, the color separation filter of horizontal four pixels is by the panchromatic transmission filter from a left side, dark green transmission filter, panchromatic transmission filter, the example that yellow transmission filter constitutes, but remain untouched and change arrangement mode with regard to other the transmit color of filter, perhaps two panchromatic transmission filters remain untouched and change over the transmit color of dark green and yellow transmission filter dark green and magenta, or magenta and yellow, perhaps red and blue, or it is red and green, or green and blue formation, can implement too.As long as in the repeat pattern of transmission filter,, just obtain same effect as the filter that repeats the non-panchromatic colour of four two panchromatic transmission filters of voxel models configuration and two kinds of each transmissions.In addition, just the pattern of the color separation filter of a vertical pixel, horizontal four pixels is vertically being prepared four kinds of patterns, the formation that the arrangement mode of the color separation filter of these four kinds of patterns has nothing in common with each other can be implemented too.
The 3rd embodiment
Just describe with Fig. 6, Fig. 7 below corresponding to the 3rd embodiment of claim 4 of the present invention, claim 5, claim 9 and claim 12.
In Fig. 6 (a), the 1st, optical system is the effect that realizes making reference object imaging on solid-state imager, is made of lens etc.The 2nd, have the solid-state imager of color separation filter, realize the reference object picture (optical image) of imaging is transformed into the effect of picture signal (electric signal).The 3rd, AD converter is becoming data image signal from solid-state imager 2 resulting image signal transformations.The 5th, memory circuit, the data image signal by 3 conversion of AD converter of a picture of storage.The 6th, the relatedness computation circuit calculates in any pixel be stored in the data image signal in the memory circuit 6 and degree of correlation surrounding pixel.The 7th, interpolation process circuit carries out interpolation based on the degree of correlation of being calculated from relatedness computation circuit 6 and handles output luminance signal and color difference signal.By these optical systems 1, have the solid-state imager 2 of color separation filter, AD converter 3, memory circuit 5, relatedness computation circuit 6, each circuit of interpolation process circuit 7 makes luminance signal and color difference signal.
The formation of the color separation filter shown in Fig. 6 (b) on the solid-state imager 2.Be one with four pixels of adjacency in length and breadth and arrange unit, the configuration of filter by two pixels in top from a left side panchromatic transmission filter, dark green transmission filter, yellow transmission filter, panchromatic transmission filter constitute following two pixels from a left side.This one arrange unit on direction in length and breadth continuously repeated configuration.
If represent to take in W pixel, Cy pixel, the Ye pixel of memory circuit (not shown) with the RGB component, then can be expressed as W=(R+G+B)/3, Cy=(G+B)/3, Ye=(R+B)/3, as make W pixel W ≈ that Y then can intactly be expressed as luminance signal to the output signal of W pixel.With regard to Cy pixel and Ye pixel, obtain R component and B component by interpolation operation, by being added to respectively on Cy pixel, the Ye pixel, just can express luminance signal.Though in interpolation, utilize the signal of surrounding pixel, calculate and the surrounding pixel of being determined by the degree of correlation of inter polated pixel to use in the interpolation by relatedness computation circuit 6.The computational methods of the degree of correlation are described at first at the very start.
Fig. 7 is being by the occasion of inter polated pixel with dark green pixel Cyn, and the configuration person of surrounding pixel is shown, ● number and be for No. zero unwanted Ye pixel and W pixel during the interpolation of this Cyn pixel is handled.Order is Hc as the horizontal degree of correlation of 1.-1. ' degree of correlation longitudinally of direction be Vc, as 2.-2. ' direction shown in Fig. 7, calculates with following formula respectively.
Vc=|Wu-Wd|+|Cyu-Cyn|+|Cyd-Cyn| (1)
Hc=|Wl-Wr|+|Cyl-Cyn|+|Cyr-Cyn| (2)
With this result, by following conditional determine the related side to.
Vc+Th<Hc (3)
Hc+Th<Vc (4)
Moreover Th is a threshold value, is specific constant.The related side is judged as vertically to the occasion of setting up in formula (3), and the occasion of setting up in formula (4) is judged as laterally.Formula (3) and all invalid occasion of formula (4) two sides be judged as do not have the related side to.
Handle with regard to interpolation below and be described.
In the pixel that the related side uses,, calculate not enough components R Cy with following formula for only being utilized surrounding pixel longitudinally by inter polated pixel Cyn in be judged as occasion longitudinally, interpolation is handled.
RCy=(Wu+Wd)/2-(2*Cyn+Cyu+Cyd)/4 (5)
Be judged as horizontal occasion, the pixel of using during interpolation is handled for only being utilized horizontal surrounding pixel by inter polated pixel Cyn, is calculated not enough components R Cy with following formula.
RCy=(Wl+Wr)/2-(2*Cyn+Cyl+Cyr)/4 (6)
In addition, be judged as do not have the related side to occasion, the surrounding pixel for utilized horizontal and vertical two sides by inter polated pixel Cyn calculates not enough components R Cy with following formula.
RCy=(Wu+Wd+Wl+Wr)/4-(4*Cyn+Cyu+Cyd+Cyl+Cyr)/8 (7)
Use by the resulting not enough components R Cy in formula (5)~(7), can be W '=Cyn+RCy being obtained by following formula by the W component of inter polated pixel Cyn.
Similarly calculated W ' for all by inter polated pixel Cyn by aforesaid operations.
In the Ye pixel is by the occasion of inter polated pixel, and the Cy in can the formula of wushu (1)~(2) changes Ye into, carries out relatedness computation, and the Cy on the right in can the formula of wushu (5)~(7) changes Ye into, obtains not full measure BYe.The not full measure of obtaining is not the R component, just becomes the B component, by making W '=Yen+BYe, can obtain the W component of Ye pixel.Similarly carried out aforesaid operations for all by inter polated pixel Yen.
Handle by implementing this interpolation, obtain the briliancy W ' at Cy pixel, Ye pixel place, can obtain all luminance signals.Use this method,, come interpolation in Cy pixel and Ye pixel place uses with the degree of correlation is high separately surrounding pixel, so can reduce the reduction of resolution because the signal of W pixel intactly uses.
As above in this 3rd embodiment, since detect by inter polated pixel and be arranged in pixel around it comprise by inter polated pixel the degree of correlation of vertical and horizontal, carry out interpolation,, can prevent the reduction of resolution so can obtain high-precision luminance signal.
The 4th embodiment
With Fig. 8 the 4th embodiment corresponding to claim 6 of the present invention is described below.
The formation with above-mentioned the 3rd embodiment is identical basically for the formation of this 4th embodiment, in this 4th embodiment and then on relatedness computation by relatedness computation circuit 6, increase the processing also calculate the oblique degree of correlation, increase oblique interpolation when relevant in this external interpolation process circuit 7 and handle.
At first be described below with regard to the computational methods of the degree of correlation.
Fig. 8 is that being illustrated in dark green pixel Cyn is by the configuration person of the surrounding pixel of the occasion of inter polated pixel, ● number and be for No. zero unwanted Ye pixel and W pixel during the interpolation of this pixel Cyn is handled.
In above-mentioned the 3rd embodiment, only obtain the degree of correlation of 1.-1. ' direction and 2.-2. ' direction shown in Fig. 7.Here further make the conduct shown in Fig. 8 3.-3. ' direction right tiltedly down the degree of correlation of direction be Nr, order is as 4.-4. ' left side of direction tiltedly down the degree of correlation of direction be Nl, calculate with following formula respectively.
Nr=|(Wu+Wl)/2-(Wd+Wr)/2|+|(Cyul-Cyn)|+|(Cydr-Cyn)| (8)
Nl=|(Wu+Wr)/2-(Wd+Wl)/2|+|(Cydl-Cyn)|+|(Cyur-Cyn)| (9)
With this result and by Vc, Hc that formula (1)~(2) are obtained by following conditional determine the related side to.
Vc+Th<min(Hc,Nr,Nl) (10)
Hc+Th<min(Vc,Nr,Nl) (11)
Nr+Th<min(Hc,Vc,Nl) (12)
Nl+Th<min(Hc,Vc,Nr) (13)
Moreover Th is a threshold value, is specific constant, and min is the function of the minimum value in each key element of getting in the bracket.The related side is judged as vertically to the occasion of setting up in formula (10), and the occasion of setting up in formula (11) is judged as laterally, and the occasion of setting up in formula (12) is judged as right tiltedly direction down, the occasion that formula (13) is set up be judged as a left side oblique under direction.Formula (10)~all invalid occasion of formula (13) be judged as do not have the related side to.
Handle with regard to interpolation below and be described.
Though in above-mentioned the 3rd embodiment, described the related side to be judged as occasion in length and breadth and be judged as do not have the related side to the interpolation of occasion handle, further appended the related side here to the processing that is judged as oblique occasion.
The related side for only utilized the right oblique surrounding pixel of direction down by inter polated pixel Cyn, calculates not enough components R Cy with following formula to being judged as the right oblique occasion of direction down.
RCy=(Wu+Wd+Wl+Wr)/4-(2*Cyn+Cyul+Cydr)/4 (14)
Being judged as the oblique occasion of direction down in a left side,, calculate not enough components R Cy with following formula for only utilized the oblique surrounding pixel of direction down in a left side by inter polated pixel Cyn.
RCy=(Wu+Wd+Wl+Wr)/4-(2*Cyn+Cyur+Cydl)/4 (15)
Similarly carry out interpolation with above-mentioned the 3rd embodiment below this and handle, obtain all luminance signals.
In this 4th embodiment, like this by not only detect in length and breadth to and also detect the oblique degree of correlation and carry out interpolation, can not only reduce in length and breadth to but also reduce the reduction of oblique resolution.
The 5th embodiment
With Fig. 9 the 5th embodiment corresponding to claim 7 of the present invention is described below.
The formation with above-mentioned the 3rd embodiment is identical basically for the formation of this 5th embodiment, in this 5th embodiment and then on relatedness computation by relatedness computation circuit 6, increase the processing of the degree of correlation of also calculating the L word direction, the interpolation when increase L word direction is relevant in interpolation process circuit 7 is handled.
At first the computational methods with regard to the degree of correlation are described.
Fig. 9 is to be the configuration person that surrounding pixel is shown by the occasion of inter polated pixel with dark green pixel Cyn, ● number and be for No. zero unwanted Ye pixel and W pixel during the interpolation of this pixel Cyn is handled.
In above-mentioned the 3rd embodiment, only obtain the degree of correlation of 1.-1. ' direction and 2.-2. ' direction shown in Fig. 7.Here further order as shown in Fig. 9 5.-5. ' degree of correlation of the upper left L word direction of direction is Lul, order is as 6.-6. ' degree of correlation of the upper right L word direction of direction is Lur, order is as 7.-7. ' degree of correlation of the lower-left L word direction of direction is Ldl, order is as 8.-8. ' degree of correlation of the bottom right L word direction of direction is Ldr, calculates with following formula respectively.
Lul=|Wu-Wl|+|Cyu-Cyn|+|Cyl-Cyn| (16)
Lur=|Wu-Wr|+|Cyu-Cyn|+|Cyr-Cyn| (17)
Ldl=|Wd-Wl|+|Cyd-Cyn|+|Cyl-Cyn| (18)
Ldr=|Wd-Wr|+|Cyd-Cyn|+|Cyr-Cyn| (19)
With this result and by Vc, Hc that formula (1)~(2) are obtained by following conditional determine the related side to.
Vc+Th<min(Hc,Lul?Ldl,Lur,Ldr) (20)
Hc+Th<min(Vc,Lul,Ldl,Lur,Ldr) (21)
Lul+Th<min(Hc,Vc?Ldl,Lur,Ldr) (22)
Lur+Th<min(Hc,Vc,Lul,Ldl,Ldr) (23)
Ldl+Th<min(Hc,Vc?Lul,Lur,Ldr) (24)
Ldr+Th<min(Hc,Vc,Lul,Ldl,Lur) (25)
Moreover Th is a threshold value, is specific constant, and min is the function of the minimum value in each key element of getting in the bracket.The related side is judged as vertically to the occasion of setting up in formula (20), the occasion of setting up in formula (21) is judged as laterally, the occasion of setting up in formula (22) is judged as upper left L word direction, the occasion of setting up in formula (23) is judged as upper right L word direction, the occasion of setting up in formula (24) is judged as lower-left L word direction, and the occasion of setting up in formula (25) is judged as bottom right L word direction.Formula (20)~all invalid occasion of formula (25) be judged as do not have the related side to.
Handle with regard to interpolation below and be described.
Though in above-mentioned the 3rd embodiment, described the related side to be judged as occasion in length and breadth and be judged as do not have the related side to the interpolation of occasion handle, further appended the processing of related side here to the occasion that is judged as the L word direction.
The related side is to the occasion that is judged as upper left L word direction, and the surrounding pixel for only utilized upper left L word direction by inter polated pixel Cyn calculates not enough components R Cy with following formula.
RCy=(Wu+Wl)/2-(2*Cyn+Cyu+Cyl)/4 (26)
In the occasion that is judged as upper right L word direction, the surrounding pixel for only utilized upper right L word direction by inter polated pixel Cyn calculates not enough components R Cy with following formula.
RCy=(Wu+Wr)/2-(2*Cyn+Cyu+Cyr)/4 (27)
In the occasion that is judged as lower-left L word direction, the surrounding pixel for only utilized lower-left L word direction by inter polated pixel Cyn calculates not enough components R Cy with following formula.
RCy=(Wd+Wl)/2-(2*Cyn+Cyd+Cyl)/4 (28)
In the occasion that is judged as bottom right L word direction, the surrounding pixel for only utilized bottom right L word direction by inter polated pixel Cyn calculates not enough components R Cy with following formula.
RCy=(Wd+Wr)/2-(2*Cyn+Cyd+Cyr)/4 (29)
Similarly carry out interpolation with above-mentioned the 3rd embodiment below this and handle, obtain all luminance signals.
In this 5th embodiment, like this by not only detect in length and breadth to and also the degree of correlation that detects the L word direction carry out interpolation, can not only reduce in length and breadth to but also reduce the reduction of the resolution of L word direction.
The 6th embodiment
Below just describe corresponding to the 6th embodiment of claim 8 of the present invention.
The formation with above-mentioned the 3rd embodiment is identical basically for the formation of this 6th embodiment, on relatedness computation by relatedness computation circuit 6, increase the processing of the degree of correlation also calculate oblique and L word direction, in the processing of interpolation process circuit 7, increase oblique interpolation processing when relevant when relevant with the L word direction.
At first the computational methods with regard to the degree of correlation are described.
In above-mentioned the 3rd embodiment, only obtain degree of correlation Vc, the Hc of 1.-1. ' direction and 2.-2. ' direction shown in Fig. 7.Here further order as shown in Fig. 8 3.-3. ' direction right tiltedly down the degree of correlation of direction be Nr, with as 4.-4. ' left side of direction tiltedly down the degree of correlation of direction be Nl, similarly obtain with above-mentioned the 4th embodiment, order as shown in Fig. 9 5.-5. ' degree of correlation of the upper left L word direction of direction is Lul, order is as 6.-6. ' degree of correlation of the upper right L word direction of direction is Lur, order is as 7.-7. ' degree of correlation of the lower-left L word direction of direction is Ldl, order is as 8.-8. ' degree of correlation of the bottom right L word direction of direction is Ldr, similarly obtains with above-mentioned the 5th embodiment.
With this result, by following conditional determine the related side to.
Vc+Th<min(Hc,Nr,Nl,Lul,Lur,Ldl,Ldr) (30)
Hc+Th<min(Vc,Nr,Nl,Lul,Lur,Ldl,Ldr) (31)
Nr+Th<min(Hc,Vc,Nl,Lul,Lur,Ldl,Ldr) (32)
Nl+Th<min(Hc,Vc,Nr,Lul,Lur,Ldl,Ldr) (33)
Lul+Th<min(Hc,Vc,Nr,Nl,Lur,Ldl,Ldr) (34)
Lur+Th<min(Hc,Vc,Nr,Nl,Lul,Ldl,Ldr) (35)
Ldl+Th<min(Hc,Vc,Nr,Nl,Lul,Lur,Ldr) (36)
Ldr+Th<min(Hc,Vc,Nr,Nl,Lul,Lur,Ldl) (37)
Moreover Th is a threshold value, is specific constant, and min is the function of the minimum value in each key element of getting in the bracket.The related side is judged as vertically to the occasion of setting up in formula (30), the occasion of setting up in formula (31) is judged as laterally, the occasion of setting up in formula (32) is judged as right oblique direction down, the occasion of setting up in formula (33) is judged as the oblique direction down in a left side, the occasion of setting up in formula (34) is judged as upper left L word direction, the occasion of setting up in formula (35) is judged as upper right L word direction, and the occasion of setting up in formula (36) is judged as lower-left L word direction, and the occasion of setting up in formula (37) is judged as bottom right L word direction.Formula (30)~all invalid occasion of formula (37) be judged as do not have the related side to.
Handle with regard to interpolation below and be described.
Though in above-mentioned the 3rd embodiment, described the related side to be judged as occasion in length and breadth and be judged as do not have the related side to the interpolation of occasion handle, it is oblique to being judged as further to have appended the related side here, and the processing of the occasion of L word direction.
The related side for only utilized the right oblique surrounding pixel of direction down by inter polated pixel Cyn, calculates not enough components R Cy with formula (14) to being judged as the right oblique occasion of direction down.Being judged as the oblique occasion of direction down in a left side,, calculate not enough components R Cy with formula (15) for only utilized the oblique surrounding pixel of direction down in a left side by inter polated pixel Cyn.The related side is to the occasion that is judged as upper left L word direction, and the surrounding pixel for only utilized upper left L word direction by inter polated pixel Cyn calculates not enough components R Cy with formula (26).In the occasion that is judged as upper right L word direction, the surrounding pixel for only utilized upper right L word direction by inter polated pixel Cyn calculates not enough components R Cy with formula (27).In the occasion that is judged as lower-left L word direction, the surrounding pixel for only utilized lower-left L word direction by inter polated pixel Cyn calculates not enough components R Cy with formula (28).In the occasion that is judged as bottom right L word direction, the surrounding pixel for only utilized bottom right L word direction by inter polated pixel Cyn calculates not enough components R Cy with formula (29).
Similarly carry out interpolation with above-mentioned the 3rd embodiment below this and handle, obtain all luminance signals.
In this 6th embodiment, like this by not only detect in length and breadth to and also detect oblique and the degree of correlation L word direction is carried out interpolation, can not only reduce in length and breadth to but also reduce the reduction of the resolution of oblique and L word direction.
The 7th embodiment
Below just describe corresponding to the 7th embodiment of claim 10 of the present invention.
The formation of this 7th embodiment is identical with the formation of above-mentioned the 3rd~6 embodiment, and just the relatedness computation method in relatedness computation circuit 6 is different with them.Though among the degree of correlation Ldr of the degree of correlation Lur of the vertical degree of correlation Vc that in above-mentioned the 3rd~6 embodiment, obtains, horizontal degree of correlation Hc, the degree of correlation Nr of right oblique direction down, degree of correlation Nl, the degree of correlation Lul of upper left L word direction of the oblique direction down in a left side, upper right L word direction, the degree of correlation Ldl of lower-left L word direction, bottom right L word direction, with coming computing each other with color pixel, but here by with the computing of the heterochromatic pixel of adjacency, obtain with the formula shown in following.
Vc=|Wu-Cyn|+|Wd-Cyn| (38)
Hc=|Wl-Cyn|+|Wr-Cyn| (39)
Nr=|(Wu+Wl)/2-Cyn|+|(Wd+Wr)/2-Cyn| (40)
Nl=|(Wu+Wr)/2-Cyn|+|(Wd+Wl)/2-Cyn| (41)
Lul=|Wu-Cyn|+|Wl-Cyn| (42)
Ldl=|Wd-Cyn|+|Wl-Cyn| (43)
Lur=|Wu-Cyn|+|Wr-Cyn| (44)
Ldr=|Wd-Cyn|+|Wr-Cyn| (45)
Below this, with regard to the related side to judgement and interpolation handle, be identical with among above-mentioned the 3rd~6 embodiment those.
Like this in this 7th embodiment, because can be by obtaining the degree of correlation, so can improve the computational accuracy of the degree of correlation with the computing of the heterochromatic pixel of adjacency.
The 8th embodiment
Below just describe corresponding to the 8th embodiment of claim 11 of the present invention.
The formation of this 8th embodiment is identical with the formation of above-mentioned the 3rd~6 embodiment, and just the interpolation processing method in interpolation process circuit 7 is different with them.
That is to say, this 8th embodiment, about in above-mentioned the 3rd~6 embodiment, obtain by inter polated pixel Cyn, in interpolation is handled, obtain this by the briliancy W ' of inter polated pixel Cyn when, without Cyn itself, only use W pixel on every side, carry out interpolation by following formula.
The related side presses to being occasion longitudinally
W’=(Wu+Wd)/2 (46)
The related side presses to being horizontal occasion
W’=(Wl+Wr)/2 (47)
The related side presses to the occasion that is upper left L word direction
W’=(Wu+Wl)/2 (48)
The related side presses to the occasion that is lower-left L word direction
W’=(Wd+Wl)/2 (49)
The related side presses to the occasion that is upper right L word direction
W’=(Wu+Wr)/2 (50)
The related side presses to the occasion that is bottom right L word direction
W’=(Wd+Wr)/2 (51)
The related side presses to being above-mentioned occasion in addition
W’=(Wu+Wd+Wl+Wr)/4 (52)
Carry out interpolation.
In this 8th embodiment,,, can obtain the high-resolution image that does not have luminance nonuniformity even so interpolation precision improves because only calculate luminance signal with W.
The 9th embodiment
With Figure 10, Figure 11 the 9th embodiment corresponding to claim 13 of the present invention and claim 14 is described below.
This 9th embodiment, be judged as it by the occasion of inter polated pixel by the detection of the degree of correlation in the foregoing description at specific directional correlation, not according to its degree of correlation, but handle so that add gain in by the color difference signal of the position of inter polated pixel (R-Y, B-Y) less than 1 at this.
Judge the degree of correlation and the relation that is added in the gain on the color difference signal of the strongest direction that becomes to be correlated with shown in Figure 10.Though pseudo-chrominance signal appears in edge part in briliancy easily, have the above-mentioned processing that adds less than 1 gain in the interpolation process circuit 7 by making, can be suppressed at the false colour that the edge part of briliancy takes place.And then, have edge detection feature concurrently owing to can make degree of correlation testing circuit 6, just can implement false colour inhibition processing so need not add the briliancy edge detect circuit in addition.
In addition, also can make the change in gain that is added on the color difference signal according to the size of the degree of correlation of judging the strongest direction that becomes to be correlated with.The judgement of this occasion shown in Figure 11 become the to be correlated with degree of correlation and one of the relation example that is added in the gain on the color difference signal of the strongest direction.But the relevant here strong more then degree of correlation is more little.
In Figure 11, provide certain width Th1 at the degree of correlation, reduce to be added in the gain on the aberration in this width gradually at each.In general, the differential big edge part of briliancy becomes dense false colour more.Just owing to relevant elimination, the possibility that produces dense false colour is big more, so can reduce the level of color difference signal according to this possibility, can suppress false colour effectively.
The 10th embodiment
Just describe with Figure 12, Figure 13, Figure 14, Figure 15 below corresponding to the 10th embodiment of claim 15 of the present invention and claim 16.Moreover, omit its explanation for the identical label of formation use identical with previous embodiment.
Figure 12 illustrates the formation according to the solid-state color imager of this 10th embodiment, and is identical with the formation shown in Fig. 6 basically, becomes the formation of having appended frequency characteristic adjustment circuit 10 in the formation of Fig. 6.The interpolation process circuit 7 of Fig. 6 is decomposed into luminance signal interpolation process circuit 8 in Figure 12 and color difference signal interpolation process circuit 9 draws, and becomes in the prime of color difference signal interpolation process circuit 9 to insert the formation that frequency characteristic is adjusted circuit 10.The picture signal that is stored in the memory circuit 5 is adjusted its frequency characteristic of adjustment in the circuit 10 in frequency characteristic, to 9 inputs of color difference signal interpolation process circuit.
Figure 13 be frequency characteristic adjust in the circuit 10 frequency band limits in low pass, the schematic diagram of action usefulness of the frequency characteristic of adjustment colour signal be described.Set up low pass filter the frequency characteristic adjustment can vertically, laterally, with carry out obliquely in length and breadth.When setting up low pass filter in the vertical, be that 2n+1 point (n=1,2 are longitudinally used in the center to be adjusted the frequency characteristic pixel ...) same chrominance signal, calculate coefficient person average that adds the characteristic of decision filter at each point.For example, for being adjusted the frequency characteristic pixel, with 3 same chrominance signals longitudinally, the output signal Cy23 ' that the frequency characteristic of setting up the occasion of low pass filter is adjusted circuit 10 can express as formula (53) with the Cy23 of Figure 13.
Cy23′=(Cy03+Cy23+Cy43)/3 (53)
When setting up low pass filter equally in the horizontal, so that to be adjusted the frequency characteristic pixel be the center with horizontal 2n+1 point (n=1,2 ...) same chrominance signal, calculate coefficient person average that adds the characteristic of decision filter at each point.For example, with the Cy23 of Figure 13 for being adjusted the frequency characteristic pixel, with 3 horizontal same chrominance signals, if coefficient all is taken as 1, the output signal Cy23 ' that the frequency characteristic of then setting up the occasion of low pass filter is adjusted circuit 10 can express as formula (54).
Cy23′=(Cy21+Cy23+Cy25)/3 (54)
When setting up low pass filter equally longitudinally and laterally, so that to be adjusted the frequency characteristic pixel be the center with vertical and horizontal (2n+1) * (2m+1) point (n, m=1,2 ...) same chrominance signal, calculate coefficient person average that adds the characteristic of decision filter at each point.For example,,,, then set up the signal of low pass filter and can as formula (55), express for being adjusted the frequency characteristic pixel with the Cy23 of Figure 13 if coefficient all is taken as 1 with vertical and horizontal 9 same chrominance signals.
Cy23′=(Cy01+Cy03+Cy05+Cy21+Cy23+Cy25
+Cy41+Cy43+Cy45)/9 (55)
When setting up low pass filter obliquely, be that 2n+2m+1 point (n, m=1,2 of cross direction are in length and breadth used in the center equally to be adjusted the frequency characteristic pixel ...) same chrominance signal, calculate coefficient average that adds the characteristic of decision filter at each point.For example,,,, then set up the signal of low pass filter and can as formula (56), express for being adjusted the frequency characteristic pixel with the Cy23 of Figure 13 if coefficient all is taken as 1 with 5 same chrominance signals of cross direction in length and breadth.
Cy23′=(Cy03+Cy21+Cy23+Cy25+Cy43)/5 (56)
This operation of adjusting frequency characteristic is at carrying out for all required colour signals of interpolation secondary colour difference signal.
For example, be by inter polated pixel with Cy23, the occasion of coming the secondary colour difference signal with the surrounding pixel of W22 and W24 when setting up low pass filter on direction in length and breadth, as formula (57), (58), (59), is calculated the required colour signal of interpolation.
W22′=(W00+W02+W04+W20+W22+W24+W40+W42+W44)/9 (57)
Cy23′=(Cy01+Cy03+Cy05+Cy21+Cy23+Cy25
+Cy41+Cy43+Cy45)/9 (58)
W24′=(W02+W04+W06+W22+W24+W26+W42+W44+W46)/9 (59)
In the color difference signal interpolation process circuit 9 of Figure 12, use above-mentioned Cy23 ', W22 ', W24 ', press following formula output R-Y color difference signal.
R-Y=A×(W22′+W24′)-B×Cy23′ (60)
In the formula, A, B are the constants by decisions such as white balances.Also by same position relation, the said frequencies characteristic is adjusted and the color difference signal interpolation is handled by implementing, and can export the B-Y color difference signal on the Ye position.
Among Figure 14 with solid line illustrate as the frequency characteristic adjustment of colour signal the amplitude response 11 during with triadic mean and as the interpolation processing of color difference signal amplitude response 12 persons of combining during with linear interpolation.Transverse axis is a frequency, and the sample frequency of colour signal is separately represented with π.If carry out linear interpolation with the colour signal of having implemented the frequency characteristic adjustment as shown in Figure 14, then can reduce the frequency component ground interpolation that comprises near the distortion of turning back the pi/2 that is included in colour signal that dots among Figure 15.
In this 10th embodiment, by such formation, the occasion that comprises high fdrequency component in the colour signal in being stored in memory circuit 5, reduce the frequency component that comprises the distortion of turning back because adjust circuit 10 by frequency characteristic, in color difference signal interpolation process circuit 9, come interpolation secondary colour difference signal, so can reduce pseudo-chrominance signal with this colour signal of having adjusted frequency characteristic.
The 11st embodiment
Just describe with Figure 16 below corresponding to the inventive embodiment described in claim 17 of the present invention and the claim 18.Moreover, with identical label, omit its explanation about the formation identical with previous embodiment.
Figure 16 illustrates the formation according to the solid-state color imager of this 11st embodiment, and is identical with the formation shown in Figure 12 basically, constitutes frequency characteristic adjustment circuit 10 and controlled by the output of degree of correlation testing circuit 6.
If with such formation, then in degree of correlation testing circuit 6, judge become to have the related side to occasion, by the colour signal of the inter polated pixel characteristic of in frequency characteristic is adjusted circuit 10, adjusting frequency.And then, with adjusted frequency characteristic this by the colour signal of inter polated pixel, computing color difference signal in color difference signal interpolation process circuit 9.Those of the processing of this occasion and above-mentioned the 10th embodiment are identical.
On the contrary, in degree of correlation testing circuit 6, judge become not have the related side to occasion, in frequency characteristic adjustment circuit 10, do not carried out any processing by the colour signal of inter polated pixel, intactly output to color difference signal interpolation process circuit 9, be used for the complementary operation color difference signal with luminance signal from luminance signal interpolation process circuit 8.
Like this in this 11st embodiment, concerning comprise high fdrequency component have the related side to colour signal, adjust circuit 10 by frequency characteristic and adjust its frequency characteristic, similarly reduce the generation of pseudo-chrominance signal with person shown in above-mentioned the 10th embodiment.On the other hand, concerning do not have the related side to colour signal owing to original just do not comprise pseudo-colouring component, thus there is no need the characteristic of adjusting frequency because the frequency component of colour signal is not because of the frequency characteristic adjustment decays, so keep the reproducibility of colour.