Abstract:
A video camera which comprises a progressive scanning CCD, a camera signal processing part for converting an output from the progressive scanning CCD to a video signal adaptive to video display, and a driving means for driving the progressive scanning CCD, and which enables to enlarge dynamic range by synthesizing a first signal obtained by exposure during a first predetermined time and a second signal obtained by exposure during a predetermined time after the exposure time of the first signal by means of the progressive scanning CCD to enlarge luminance gradation characteristics on appearance further includes at least a separating portion for separating the first signal and the second signal which are output from the progressive scanning CCD at different timings, a signal synthesizing portion for synthesizing the first signal and the second signal to produce a synthesized signal, and a delay portion for receiving the first signal output from the separating portion and for delaying the first signal by a predetermined time so that the second signal and the first signal are simultaneously input to the signal synthesizing portion.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a video camera and, more particularly, to a video camera that can perform enlargement of dynamic range of such as a video movie, successive picturing of frame still images, and enlargement of dynamic range of frame still images. 
     DESCRIPTION OF PRIOR ART 
     Operation of Prior Art 
     As a method for enlarging the dynamic range of a video camera, there is a method which is described in Japanese Published Patent Application No. Hei 6-13207. In this method, a first exposure signal such as a long term exposure signal (hereinafter, “Slong signal”) and a second exposure signal such as a short term exposure signal (hereinafter, “Sshort signal”) are synthesized, thereby enlarging the dynamic range on appearance. 
     This method will be briefly described with reference to the drawings. 
     FIG. 17 is a block diagram illustrating an example of construction of a prior art video camera  6 . FIG. 18 is a diagram schematically showing the storage state and transferring state of Slong signals and Sshort signals which are light-electricity converted by a progressive scanning CCD  11  in the prior art video camera. 
     This video camera  6  is constituted by a taking lens  10 , a progressive scanning CCD  11 , a switch  12 , a signal synthesizing means  18 , and a camera signal processing part  20 . 
     In addition, the progressive scanning CCD  11  is constituted by light-electricity conversion parts  50 , vertical transfer parts  52  transferring charges in the vertical direction, which charges are transferred from the light-electricity conversion parts  50 , a horizontal transfer part  54  which outputs serially in the horizontal direction the charges which are transferred from the vertical transfer parts  52 , and an output amplifier  56  which amplifies output of the horizontal transfer part  54 . 
     The light-electricity conversion part  50  comprises photodiodes  51 , the number of which corresponds to the pixel number, and the vertical transfer part  52  comprises a plurality of CCD  53  which are respectively vertically arranged respectively corresponding to the photodiode  51 . 
     While in FIG. 18 an array which has 4 rows of pixels and 6 columns of pixels is illustrated, in an actual construction of such as VGA (Video Graphics Array), a construction which has 640 rows of pixels and 480 columns of pixels is adopted. 
     In the video camera  6  constructed as above, the light incident to the video camera through the taking lens  10  is light-electricity converted in the progressive scanning CCD  11 . 
     In other words, in this progressive scanning CCD  11 , as shown in FIG. 19, in the period of one field, i.e., the vertical scanning period (hereinafter also referred to as “1V”), the exposure time is switched between the long exposure time T1′ and the short exposure time T2′ by means of an electronic shutter (not shown here) so that the exposure amount against the light-electricity conversion part  50  in the progressive scanning CCD  11  may be different. 
     Here, T1′ is set to about {fraction (1/60)} second, and T2′ is set to about {fraction (1/1000)} second. Video images of one screen are respectively imaged during T1′ and T2′, thereby outputting a signal to the vertical transfer part  52  at the timing shown in FIG.  19 . The signal read out during T1′ becomes a Slong signal and the signal read out during T2′ becomes a Sshort signal. 
     The Slong signals and the Sshort signals which are obtained with light-electricity converted by the respective photodiodes  51  of the light-electricity conversion part  50  are read out to the vertical transfer part  52  as shown by arrows in the figure so that outputs from the upper and lower photodiodes  51  which are adjacent each other are added respectively, in a vertical blanking period (in this case during T1′-T2′). Therefore, in the vertical transfer part  52 , the Slong signal and the Sshort signal are respectively stored at the position of CCD  53  designated by a black circle and at the position of CCD  53  designated by a white circle, alternatingly. 
     Therefore, the respective Slong signal and Sshort signal stored in the vertical transfer part  52  are transferred alternatingly to the horizontal transfer part  54  by line by line, and thereby they are output from the light-electricity conversion part  50  through the output amplifier  56 . Accordingly, when, for example, the progressive scanning CCD  11  comprises 480 pixels in the vertical direction, Slong signals of 240 lines and Sshort signals of 240 lines are respectively output from the light-electricity conversion part  50  in the period of one field, i.e., 1V. 
     After the Slong signal and the Sshort signal, which are serially output line by line from the progressive scanning CCD  11 , are separated into the Slong signal and the Sshort signal by the switch  12 , these signals are synthesized in the signal synthesizing means  18  to be output to the camera signal processing part  20  as a signal of one series. Accordingly, in the case of non-interlacing system, the above example results in synthesized signals of 240 lines (hereinafter, “Smix signal”) in the period of one field, i.e., 1V. 
     Here, while as shown in FIG. 20 the above Slong signal is saturated at the light incident amount of L1′ due to the large exposure amount, this Slong signal has a large change of signal level at the light incident amount below that, thereby resulting in a preferred S/N ratio and keeps the gradation at the low luminescent part. 
     On the other hand, while the Sshort signal has low gradation at the low luminescent part due to the low exposure amount, it keeps the gradation without saturating up to the high luminescent part on the contrary. Therefore, the gradation characteristics of the Smix signal, which has synthesized the both, is enlarged relative to the gradation characteristics of the Slong signal only, and thus, the dynamic range on appearance is enlarged. 
     In this way, the Smix signal whose dynamic range is thus enlarged by the signal synthesizing means  18  is processed to a video signal which is adaptive to the television display (such as NTSC system) by the camera signal processing means  20 , and is output to the outside. 
     PROBLEMS TO BE SOLVED 
     However, the above-described prior art video camera  6  has the following problems. 
     First of all, since in the prior art video camera  6  T1′ is set to {fraction (1/60)} sec. and T2′ is set to {fraction (1/1000)} sec. as described above, the enlargement rate (θ1′/θs′) of dynamic range in this case is about 16 times [≈({fraction (1/60)})/({fraction (1/1000)})]. 
     However, when T2′ is quite a short time, such as when T2′ is {fraction (1/1000)} sec., not only the S/N ratio of the Sshort signal itself is insufficient but also the gradation of the video image imaged by the video camera  6  becomes insufficient as well. 
     In other words, in case where such enlargement rate of dynamic range amounts to about 16, and when the scenery inside the room and that outside as shown in FIG. 21 are imaged together, while the video images of the clear part  72  (scenery outside) and of the dark part  71  (inside the room) are obtained as clear ones, the video images of the intermediate part  73  (periphery of a window, such as a desk adjacent to the window) for which the enlargement rate of dynamic range of about 2˜4 times is made the most appropriate cannot be made clear images due to the too large enlargement rate of dynamic range in the prior art device, thereby resulting in a large problem. 
     With reference to FIG. 20, this problem is explained as a fact that when the light incident amount is within a range of L1′ to L2′, since the signal level of the Sshort signal at that timing is low while the Slong signal is saturated, the S/N ratio is deteriorated, whereby the Smix signal is affected by noise components to result in non-preferred video images. 
     In the above-described prior art video camera  6 , when the progressive scanning CCD  11  is used for enlargement of dynamic range, it is not possible to accomplish the inherent object as the progressive scanning CCD  11  itself, i.e., to obtain the progressive scanning output, particularly, the output that has enhanced the picture quality by vertical high frequency emphasizing. 
     More particularly, though in the above-described video camera  6  it is intended that Slong signals of 240 lines and Sshort signals of 240 lines are respectively output from the progressive scanning CCD  11  in the period of one field, the both signals are synthesized by the signal synthesizing means  18 , resulting in only Smix signals of 240 lines. Therefore, it was not possible to utilize the video camera in case where high quality video image of 480 lines should be printed out by non-interlacing system, for example. 
     It is an object of the present invention to provide a video camera in which the practical enlargement rate of dynamic range, such as two times to four times, can be obtained, and further the progressive scanning CCD can be used for the enlargement of dynamic range and progressive scanning output. 
     SUMMARY OF THE INVENTION 
     To solve the above problem, a video camera comprising a progressive scanning CCD, a driving means for driving the progressive scanning CCD, and a camera signal processing part for converting an output of the progressive scanning CCD to a video signal adaptive to a video image display, and enabling enlarging dynamic range by synthesizing a first signal which is obtained by exposure during a first predetermined time and a second signal which is obtained by exposure during a predetermined time after the exposure time of the first signal, by means of the progressive scanning CCD and enlarging luminance gradation characteristics on appearance, which further comprises a separating means for separating the first signal and the second signal which are output from the progressive scanning CCD at different timings, a signal synthesizing means for synthesizing the first signal and the second signal to produce a synthesized signal, and a delay means for receiving the first signal output from the separating means and delaying the first signal by a predetermined time so that the second signal and the first signal are simultaneously input to the signal synthesizing means. 
     A video camera comprising a progressive scanning CCD, and a camera signal processing part for converting an output from the progressive scanning CCD to a video signal adaptive to video image display, and enabling enlarging dynamic range by synthesizing a first signal which is obtained by exposure during a first predetermined time and a second signal which is obtained by exposure during a second predetermined time after the exposure time of the first signal, by means of the progressive scanning CCD to enlarge luminance gradation characteristics on appearance, which further comprises the progressive scanning CCD enabling outputting the first signal and the second signal at different timings, a signal separating switch for separating the first signal and the second signal which are output from the progressive scanning CCD, a delay means for delaying an output from the signal separating switch by one horizontal scanning period, a first memory for temporarily storing an output from the delay means, a second memory for temporarily storing the second signal which is output from the signal separating switch, a first scanning conversion means for converting an output from the first memory to a normal speed signal, a second scanning conversion means for converting an output from the second memory to a normal speed signal, and a synthesizing means for synthesizing the first signal and the second signal, synchronized and having normal speeds, which are output from the first scanning conversion means and the second scanning conversion means. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a block diagram illustrating a construction of a video camera according to a first embodiment of the present invention. 
     FIG. 2 is a timing diagram illustrating the signal output from a progressive scanning CCD of the video camera according to the first embodiment of the present invention. 
     FIG. 3 is a diagram showing the signal transfer timing in the video camera according to the first embodiment of the present invention. 
     FIG. 4 is a characteristic diagram showing the relation between the Sshort signal, Slong signal, and Smix signal in the video camera according to the first embodiment of the present invention. 
     FIG. 5 is a block diagram illustrating a video camera according to an embodiment in which a part of the video camera according to the first embodiment of the present invention is omitted. 
     FIG. 6 is a block diagram illustrating a construction of a video camera according to a second embodiment of the present invention. 
     FIG. 7 is a block diagram illustrating a concrete construction of a vertical high frequency emphasizing means in FIG.  6 . 
     FIG. 8 is a block diagram illustrating a construction of a video camera according to a third embodiment of the present invention. 
     FIG. 9 is a block diagram illustrating a concrete construction of a vertical high frequency emphasizing means in FIG.  8 . 
     FIG. 10 is a block diagram illustrating a construction of a video camera according to a fourth embodiment of the present invention. 
     FIG. 11 is a block diagram illustrating the video camera according to the fourth embodiment of the present invention when the mode of enlarging the dynamic range is selected. 
     FIG. 12 is a block diagram illustrating the video camera according to the fourth embodiment of the present invention when the mode of successively picturing frames is selected. 
     FIG. 13 is a block diagram illustrating the video camera according to the fourth embodiment of the present invention when the mode of enlarging the dynamic range for frame still images is selected. 
     FIG. 14 is a diagram illustrating the timing of a signal being output from a progressive scanning CCD in the video camera according to the fourth embodiment of the present invention. 
     FIG. 15 is a timing diagram showing the operation of the video camera according to the fourth embodiment of the present invention. 
     FIG. 16 is a block diagram showing a construction of a video camera according to a fifth embodiment of the present invention. 
     FIG. 17 is a block diagram illustrating a construction of a prior art video camera. 
     FIG. 18 is a schematic diagram illustrating the storage and transferring states of Slong signals and Sshort signals which are obtained with light-electricity converted by the progressive scanning CCD in the prior art video camera. 
     FIG. 19 is a diagram showing the timing of a signal output from the progressive scanning CCD of the prior art video camera. 
     FIG. 20 is a characteristic diagram showing the relation between the Sshort signal, Slong signal, and Smix signal in the prior art video camera. 
     FIG. 21 is a diagram illustrating an example of scenery which is to be imaged by a video camera. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     First Embodiment 
     First of all, an example of a video camera according to the present invention which enables enlarging the dynamic range to about twice as well as appropriately switching the mode of progressive scanning CCD to a dynamic range enlarging mode or to a progressive scanning outputting mode, will be described with reference to the drawings as a first embodiment of the present invention. 
     FIG. 1 is a block diagram illustrating a construction of a video camera  1  according to the first embodiment of the present invention. This video camera  1  performs the same operation as that of the prior art video camera  6  shown in FIG. 17, and the same reference numerals designate the same elements. 
     This video camera  1  is constituted by a taking lens  10 , a progressive scanning CCD  11 , a first switch  12 , a delay means  13 , a first scanning conversion means  15 , a second scanning conversion means  16 , a signal adding means  17 - 1 , a signal synthesizing means  18 , a second switch  19 , and a camera signal processing part  20 . 
     Here, the progressive scanning CCD  11  is supposed to be constituted with 480 pixels in the vertical direction for simplifying the understanding. 
     In addition, in this progressive scanning CCD  11 , when the mode in which the dynamic range of the output is enlarged (hereinafter, “dynamic range enlarging mode”) is selected, as shown in FIG. 2, in the period of one field, i.e., the vertical scanning period (1V), the exposure time is switched between the long exposure time T1 as a first predetermined time and the short exposure time T2 as a second predetermined time by means of, for example, an electronic shutter (not shown here) so that the exposure amount against the light-electricity conversion part  50  in the progressive scanning CCD  22  may be different. 
     Here, T1 is set to about {fraction (1/90)} sec. and T2 is set to about {fraction (1/180)} sec. The signal read out at T1 is an Slong signal and the signal read out at T2 is an Sshort signal. In this embodiment, the exposure time T2 for obtaining the Sshort signal is sufficiently longer than that in the prior art video camera  6 , i.e., T2&gt;&gt;T2′. 
     Further, when the dynamic range enlarging mode is selected in the progressive scanning CCD  11 , similarly as in the case of the progressive scanning CCD  11  used in the prior art video camera  6  shown in FIG. 18, the Slong signals and the Sshort signals which are output from the upper and lower photodiodes  51  which are adjacent each other, of the light-electricity conversion part  50  are added at the respective CCDs  53  in the vertical transfer parts  52 . 
     In this first embodiment, the values of T1 and T2 are not limited thereto, and can be appropriately set in accordance with the enlargement rate of dynamic range. In addition, in this first embodiment, the transfer operation in the horizontal transfer part  54  is temporarily stopped with the Slong signal is read out to the vertical transfer part  52  from the light-electricity conversion part  50 . 
     Further, when the output of this progressive scanning CCD  11  is progressively scanned (hereinafter, referred to as “progressive scanning mode”), the exposure time is not switched but a video image of one screen is imaged in one field period (1V) by the light-electricity conversion part  50  to obtain the Slong signal, and this is read out to the CCDs  53  which correspond to the respective photodiodes  51 . 
     Accordingly, the outputs of the respective upper and lower photodiodes  51  which are adjacent each other are not added as when the dynamic range of the output of the progressive scanning CCD  11  is enlarged (hereinafter, referred to as “dynamic range enlarging mode”). 
     Therefore, when the progressive scanning mode is selected, the signal charges of the Slong signals of 480 lines are stored at the vertical transfer part  52 . 
     The first switch  12  provides a separating means for selecting and separating the Slong signal and the Sshort signal which are output from the progressive scanning CCD  11  to output the same. 
     The first scanning conversion means  15  and the second scanning conversion means  16  perform adjustment such that each line of the Slong signal and the Sshort signal are output for the time corresponding to one horizontal scanning period (hereinafter, also referred to as “1H”), and these comprise dual port memories which can control the writing speed and the reading speed independently. 
     The first scanning conversion means  15  and the second scanning conversion means  16  are respectively controlled such that the reading speed is a half of the writing speed when the dynamic range enlarging mode is selected in the progressive scanning mode CCD  11 , and the reading speed is equal to the writing speed when the progressive scanning mode is selected. 
     The signal synthesizing means  18  outputs a synthesized signal of one system, comprising an Slong signal and an Sshort signal synthesized with each other, i.e., an Smix signal. 
     The signal adding means  17 - 1  is used when the progressive scanning mode is selected in the progressive scanning CCD  11  and adds both Slong signals before and after the first scanning conversion means  15  together. This corresponds to adding the Slong signals of the pixels which are adjacent each other in the vertical direction. 
     The second switch  19  is switched such that is outputs the output of the signal synthesizing means  18  when the dynamic range enlarging mode is selected in the progressive scanning CCD  11  and it outputs the output of the signal adding means  17 - 1  when the progressive scanning mode is selected. 
     The operations of respective parts when the dynamic range enlarging mode is selected in the video camera  1  constituted as above, and when the progressive scanning mode is selected are described. 
     (1) when the dynamic range enlarging mode is selected 
     When this mode is selected, first of all, the light incident through the taking lens  10  is light-electricity converted in the progressive scanning CCD  11  to result in a Slong signal and a Sshort signal, thereby being output to the next stage. 
     On the other hand, in accordance with the controller which is not shown here, the output of the progressive scanning CCD  11  is switched by the second switch  19  so that the output of the signal synthesizing means  18  is selected. 
     In other words, in the progressive scanning CCD  11 , as shown in FIG. 2, the exposure time is respectively switched to T1={fraction (1/90)} sec. and T2={fraction (1/180)} sec. in the period of one field (1V) and the video image of one screen is imaged during T1 and T2. 
     The Slong signals obtained by light-electricity conversion by the respective photodiodes  51  of the light-electricity conversion means  50  are read out to the vertical transfer part  52  at the end point of T1 shown in FIG.  2  and the outputs of the upper and lower photodiodes  51  which are adjacent each other are respectively added together. Next, the Sshort signals are similarly added at the end point of T2. Accordingly, the Slong signal and the Sshort signal are alternatingly stored in the vertical direction in the vertical transfer part  52 . 
     The Slong signal and Sshort signal stored at the vertical transfer part  52  are respectively transferred to the horizontal transfer part  54  alternatively line by line, and output through the output amplifier  56 . 
     Accordingly, when the progressive scanning CCD  11  is constituted by 480 pixels in the vertical direction as in this embodiment, as shown in FIG. 3, the Slong signals of 240 lines and the Sshort signals of 240 lines are output in one field period (1V), and the output timings of the Slong signal and the Sshort signal are shifted by the exposure time T2 (={fraction (1/180)} sec.). 
     When limited to the one field period, the Slong signal is output prior to the Sshort signal by T2. 
     The Slong signal and the Sshort signal which are thus serially output alternatingly line by line from the progressive scanning CCD  11  are separated by the first switch  12  from each other, and the Slong signal is input to the first scanning conversion means  15  after being delayed by T2 by the delay means  13 , and the Sshort signal is input to the second scanning conversion means  16  as it is. 
     The Slong signal and the Sshort signal which are stored at the first scanning conversion means  15  and the second scanning conversion means  16  at one line unit, are read out at a reading out speed which is equal to a half of the writing speed so as to correspond to the one horizontal scanning period (1H) under the interlacing system, and are output to the next stage signal synthesizing means  18  to by synthesized to result in an Smix signal. Accordingly, in the case of interlacing system, the Smix signals of 240 lines in one vertical scanning period (1V) can be obtained. 
     Here, in this embodiment, T1 is set to {fraction (1/90)} sec. and T2 is set to {fraction (1/180)} sec. and the enlargement ratio of the dynamic range (θ1/θs) becomes twice [=({fraction (1/90)})/({fraction (1/180)})]. 
     The Smix signal which is output from the signal synthesizing means  18  is given to the camera signal processing part  20  through the second switch  19 , and a predetermined signal processing is applied thereto to be output. 
     In this way, the exposure time T2 for the Sshort signal is secured sufficiently longer than in the prior art and the S/N ratio of the Sshort signal itself is preferable and sufficient gradation is obtained. 
     Therefore, in FIG. 4, when the light incident amount is within the range of L1˜L2, the Slong signal is saturated while the Sshort signal has a large signal level. Therefore, relative to the prior art device shown in FIG. 17, the S/N ratio is improved, and as a result, the Smix signal is less affected by the noise components and a preferred display image is obtained. 
     (2) when the progressive scanning mode is selected 
     When this mode is selected, first of all, the light incident through the taking lens  10  is light-electricity converted in the progressive scanning CCD  11  to be output to the next stage. 
     On the other hand, in accordance with the controller not shown here, the output of the progressive scanning CCD  11  is switched by the second switch  19  so as to select the output of the signal adding means  17 - 1 . 
     In this progressive scanning mode, the switching of the exposure time is not performed but video image of one screen is imaged within one field period (1V) to obtain an Slong signal, and this signal is read out to the respective CCDs  53  which individually correspond to the respective photodiodes  51 , whereby the signal charges of the Slong signals of 480 lines are stored at the vertical transfer part  52 . Therefore, the outputs of the upper and lower photodiodes  51  adjacent to each other are not added together as at the dynamic range enlarging mode. 
     In this way, the output from the progressive scanning CCD  11  is progressively scanned line by line, and after being delayed by time T2, input to the first scanning conversion means  15 . 
     in this progressive scanning mode, the first scanning conversion means  15  functions as a 1H delay element which delays a signal by 1H. In other words, the Slong signal which is stored by one line unit is read out at the same speed as the writing speed so as to correspond to 1H under the non-interlacing system to be output with delayed by 1H. 
     The Slong signal of one line before being input to the first scanning conversion means  15  and the Slong signal of one line which is delayed by 1H by the first scanning conversion means  15  are input to the signal adding means  17 - 1 , respectively. 
     The signal adding means  17 - 1  mutually adds the Slong signals of two lines which are adjacent each other in the vertical direction at pixel units. By this signal addition, in the later stage camera signal processing part, the same processing as processing the signals which are obtained by charge addition on CCD  53  can be performed as conventionally. 
     The output of the signal adding means  17 - 1  is input to the camera signal processing part  20  through the second switch  19 , and it is subjected to the predetermined signal processing by the camera signal processing part  20  to be output as a non-interlacing system scanning signal. 
     Here, a switch may be provided between the delay means  13  and the first scanning conversion means  15  to selectively output the Slong signal of the CCD  11  divided in two fields, thereby realizing the interlacing processing. 
     Further, in the above-described video camera  1 , in order to simplify the structure, the signal adding means  17 - 1  can be omitted from the material constituting the video camera  1  as well as the first scanning conversion means  15 , the second scanning conversion means  16 , and the second switch  19  can be omitted as shown in FIG.  5 . 
     Second Embodiment 
     Next, a video camera  2  according to the present invention, which is the above-described video camera  1  further including a third switch  23  and a vertical high frequency emphasizing means  24 - 2 , will be described with reference to the drawings. 
     FIG. 6 is a block diagram illustrating a construction of the video camera  2 , and the same reference numerals in FIG. 1 designate the same elements as in the video camera  1 . 
     The third switch  23  can be switched such that it selects and outputs the Sshort signal selected by the first switch  12  when the dynamic range enlarging mode is selected in the progressive scanning CCD  11 , and it selects and outputs the Sshort signal output from the first scanning conversion means  15  when the progressive scanning mode is selected. 
     The vertical frequency emphasizing means  24 - 2  is to extract vertical frequency emphasizing components based on the Slong signals of three lines before and after in the vertical direction. As shown in FIG. 7, it is constituted by an adding unit  30  adding the Slong signal output from the delay means  13  and the Slong signal delayed to be output from the second scanning conversion means  16 , an attenuator  31  attenuating the output of the adding unit  31  to a half level, a subtracting unit  32  subtracting between the output of the attenuator  31  and the Slong signal delayed and output by the first scanning conversion means  15 , and an output amplifier  33  for gain adjustment. 
     Since the other construction is similar to that of the video camera  1  shown in FIG. 1, the detailed description is omitted here. 
     Next, the operation of the above construction is described. 
     (1) when the dynamic range enlarging is selected 
     When this mode is selected, by the controller which is not shown here, the second switch  19  is switched so as to select the output of the signal synthesizing means  18  and the third switch  23  is switched so as to select the Sshort signal from the first switch  12 , respectively. 
     Since the basic operation until the Smix signal is obtained based on the Slong signal and the Sshort signal output from the progressively scanning CCD  11  is similar to that in the case of the above-described video camera  1 , the description is omitted here. 
     (2) when the progressive scanning mode is selected 
     When this mode is selected, by the controller not shown here, the second switch  19  is switched so as to select the output of the signal adding means  17 - 2  and the third switch  23  is switched so as to select the Slong signal from the first scanning conversion means  15 , respectively. 
     The first scanning conversion means  15  and the second scanning conversion means  16  respectively functions as a 1H delay element which delays an input signal by 1H. 
     Accordingly, in the vertical high frequency emphasizing means  24 - 2 , the three signals of the Slong signal output from the delay means  13 , the Slong signal delayed by 1H by the first scanning conversion means  15 , and the Slong signal which passes through the first scanning conversion means  15  and the third switch  23 , and are delayed further by 1H by the second scanning conversion means  16 , i.e., the Slong signals of three lines which are adjacent each other in the vertical direction, are input. 
     The vertical high frequency emphasizing means  24 - 2 , after adding the Slong signal output from the delay means  13  and the Slong signal delayed and output by the second scanning conversion means  16  by means of the adding unit  30  provided therein, attenuates the output of the adding unit  30  to a half level by the next attenuator  31 , and subsequently subtracts between the output of the attenuator  31  and the Slong signal delayed and output by the first scanning conversion means  15 , by means of the subtracting unit  32 . In this way, the vertical high frequency components are extracted and the signal thereof is output to the next stage from the vertical high frequency emphasizing means  24 - 2  after being gain adjusted by the output amplifier  33 . 
     Then, the signal of the vertical high frequency emphasizing component extracted by the vertical high frequency means  24 - 2  is given to the signal adding means  17 - 2  together with the Slong signal output from the delay means  13  and the Slong signal delayed by 1H by the first scanning conversion means  15 . 
     The signal adding means  17 - 2  adds the Slong signals of two lines which are adjacent each other in the vertical direction, at pixel units and further adds to the addition result the vertical high frequency components. And it inputs the result to the camera signal processing part  20  through the second switch  19  to be output as a non-interlacing system scanning signal after being subjected to the predetermined signal processing. 
     In this way, in the video camera  2  shown in the second embodiment, the signal output from the signal adding means  17 - 2  is high frequency emphasized in the vertical direction. Therefore, it can be intended to realize the high resolution in the vertical direction as well as to avoid washboards as compared to the video camera  1 . 
     Third Embodiment 
     A video camera  3  which is the above-described video camera  2  further including a 1H memory  25  and in which a vertical high frequency emphasizing means  24 - 3  is constituted as shown in FIG. 8, will be described as a third embodiment of the present invention with reference to the drawings. 
     FIG. 8 is a block diagram illustrating a construction of the video camera  3 , and the same reference numerals designate the same elements as in the video camera  2  shown in FIG.  6 . 
     While in video camera  2 , the vertical high frequency emphasizing components are extracted based on the Slong signals of three lines which are adjacent each other in the vertical direction, in this video camera  3 , it is characterized in that the vertical high frequency emphasizing components are extracted based on the Slong signals of four lines which are adjacent each other in the vertical direction. 
     Here, the 1H memory  25  is to delay the Slong signal of one line by 1H. 
     The vertical high frequency emphasizing means  24 - 3  is constituted, as shown in FIG. 9, by a first adding unit  35  adding the Slong signal output from the delay means  13  and the Slong signal delayed and output by the 1H memory  25 , a second adding unit  36  adding the Slong signal delayed and output by the first scanning conversion means  15  and the Slong signal delayed and output by the second scanning conversion means  16 , a subtracting unit  37  subtracting the output of the first adding unit  35  from the output of the second adding unit  36 , an attenuator  39  attenuating the output of the subtracting unit  37  to a half level, and an output amplifier  40  for gain adjustment. 
     Since the other construction is similar to that of the video camera  2  shown in FIG. 6, the detailed description is omitted here. 
     Next, the operation of the above construction is described. 
     (1) when dynamic range enlarging mode is selected 
     When this mode is selected, by the controller not shown here, the second switch  19  is switched so as to select the output of the signal synthesizing means  18  and the third switch  23  is switched so as to select the Sshort signal output from the first switch  12 , respectively. 
     Since the basic operation until the Smix signal is obtained based on the Slong signal and the Sshort signal output from the progressive scanning CCD  11  is similar to that in the case of the above-described video camera  1 , the description is omitted here. 
     (2) when the progressive scanning mode is selected 
     When this mode is selected, by the controller not shown here, the second switch  19  is switched so as to select the output of the signal adding means  17 - 3  and the third switch  23  is switched so as to select the Slong signal from the first scanning conversion means  15 , respectively. 
     As in the case of the above-described video camera  2 , the first scanning conversion means  15  and the second scanning conversion means  16  respectively function as a 1H delay element which delays a signal by 1H. 
     Accordingly, in the vertical high frequency emphasizing means  24 - 3 , four signals of the Slong signal output from the delay means  13 , the Slong signal delayed by 1H by the first scanning conversion means  15 , the Slong signal which passes through the first scanning conversion means  15  and the third switch  23  and is delayed further by 1H by the second scanning conversion means  16 , and the Slong signal which passes further the 1H memory  25  from the second scanning conversion means  16  to be delayed by 1H, i.e., the Slong signals of four lines which are adjacent each other, are input together. 
     The vertical high frequency emphasizing means  24 - 3  adds by the adding unit  35  the Slong signal output from the delay means  13  and the Slong signal delayed and output by the 1H memory  25 , while it adds by the adding unit  36  the Slong signal delayed and output by the first scanning conversion means  15  and the Slong signal delayed and output by the second scanning conversion means  16 . The subtracting unit  37  subtracts the output of the first adding unit  35  from the output of the second adding unit  36 , and subsequently the vertical high frequency emphasizing components are extracted by attenuating the output of the subtracting unit  37  to the ½ level by the attenuator  39 , and the signal thereof is gain adjusted by the output amplifier  40  to be output. 
     The signal of the vertical high frequency emphasizing component extracted by the vertical high frequency emphasizing means  24 - 3  is given to the signal adding means  17 - 3  together with the Slong signal output from the delay means  13  and the Slong signal delayed by 1H by the first scanning conversion means  15 . 
     The signal adding means  17 - 3  adds the Slong signals of two lines which are adjacent each other in the vertical direction in the progressive scanning CCD  11 , at pixel units, and further adds to this the vertical high frequency emphasizing component to be output in the next stage. The signal output from the signal adding mean  17 - 3  is input to the camera signal processing part  20  through the second switch  19 , and it is subjected to the predetermined signal processing by the camera signal processing part  20  to be output as a non-interlacing system scanning signal. 
     In this way, in the third embodiment, the vertical high frequency emphasizing is performed with respect to the Slong signals of at least four lines in the vertical direction in the progressive scanning CCD  11  by the vertical high frequency emphasizing means  24 - 3 . Therefore, it is possible to realize the vertical high resolution in the vertical high frequency emphasizing, thereby improving the quality of the video image. 
     In the third embodiment, while an example which uses two scanning conversion means  15  and  16  and only one 1H memory  25  is shown, a construction in which more scanning conversion means and more 1H memories than in this case are used is also possible. 
     Fourth Embodiment 
     Further, a video camera  4  according to the present invention having a construction which is partly different from those of the above-described video camera  1 , video camera  2 , and video camera  3 , will be described with reference to the drawings. 
     FIG. 10 is a block diagram illustrating the construction of the video camera  4 . 
     In FIG. 10, the reference numeral  110  designates a taking lens, the numeral  111  designates a progressive scanning CCD, the numeral  113  designates a 1H delay means delaying a signal by 1H. The numeral  114  designates a first adding means, the numeral  119  designates a second adding means, the numeral  117  designates a first memory, and the numeral  118  designates a second memory. The numeral  122  designates a first scanning conversion means making the sampling rate to a half, and the numeral  123  designates a second scanning conversion means making the sampling rate to a half. The numeral  124  designates a signal synthesizing means and the numeral  126  designates a digital signal processor (hereinafter “DSP”) as a camera signal processing part. The numeral  128  designates a third scanning conversion means making the sampling rate to twice, and the numeral  129  designates a control means for controlling the driving method of the progressive scanning CCD  111 . In addition, the numerals  112 ,  115 ,  116 ,  120 ,  121 ,  125 , and  127  designate first to seventh switches. The respective operation modes of the video camera  4  of the enlargement of dynamic range, the successive picturing of frames, and the enlargement of dynamic range of frame still images are realized by appropriately operating these switches and the control means  129 . 
     Here, one horizontal period in the 1H delay means  113  is one horizontal period in progressively scanning, i.e., a half horizontal period in interlaced scanning (standard television signal). 
     Hereinafter, in the video camera  4  constructed as above, the operations of respective parts when dynamic range enlarging mode (the state in which the dynamic range of output of the progressive scanning CCD  111  is enlarged) is selected, when the mode of successively picturing frames (state in which output of the progressive scanning CCD  111  is adapted to the successively picturing of frame) is selected, and when the mode of enlarging dynamic range for frame still images (state in which output of the progressive scanning CCD  111  is adapted to the frame still image and the dynamic range of this frame still image is enlarged) is selected, will be described. 
     (1) when the dynamic range enlarging mode is selected 
     FIG. 11 is a block diagram illustrating the construction when this mode is selected. In other words, it is the construction in which inputs of the second switch  115 , the third switch  116 , the fourth switch  120 , the fifth switch  121 , the sixth switch  125 , and the seventh switch  127  are fixed to one side in the construction shown in FIG.  10 . 
     First, the light incident through the taking lens  110  is light-electricity converted in the progressive scanning CCD  111 . Since the operation of the progressive scanning CCD  111  is similar to that of the above-described progressive scanning CCD  11 , the description is omitted here. In this case, a first exposure time T 1  is set to {fraction (1/90)} sec. and a second exposure time T 2  is set to {fraction (1/180)} sec. 
     The outputs from the progressive scanning CCD  111  are separated into the Slong signal and the Sshort signal by the first switch  112 , the Slong signal is input to the 1H delay means  113  and the Sshort signal is input to the second memory  118  through the second switch  116 . 
     The 1H delay means  113  delays the Slong signal by one horizontal period to be output at the same timing as the Sshort signal, and inputs the same to the first memory  117  through the second switch  115 . Here, the progressive scanning CCD  111  enables to output a television signal which has the scanning lines twice as many as those of a normal television signal (such as a NTSC signal). Therefore, the numbers of the lines of the Slong signal and the Sshort signal in one vertical period are both the same as the number of the scanning lines of a standard television signal. In other words, the Slong signal and the Sshort signal exist only in a half period of one horizontal period of the standard television signal. 
     As the first memory  117  and the second memory  118 , a DRAM can be used, for example. In this video camera  4 , as described above, the inputs to the first memory  117  and the second memory  118  exist only in a half period of one horizontal period of the standard television signal. Therefore, even if the first memory  117  and the second memory  118  are DRAMs of one port, the writing period and the reading period can be alternatingly switched. 
     The output timings of the first memory  117  and the second memory  118  are set so as to correct the time lag between the Slong signal and the Sshort signal to synthesize the signals. In other words, the Slong signal is read out from the first memory  117  at the reading time which is delayed by time (T 2 −T 1 ). As a result, the Slong signal from the first memory  117  and the Sshort signal from the second memory  118  can be synchronized. 
     The outputs of the first memory  117  and the second memory  118  are input to the first scanning conversion means  122  and the second scanning conversion means  123  through the fourth switch  120  and the fifth switch  121 , respectively. The first scanning conversion means  122  and the second scanning conversion means  123  convert the Slong signal and the Sshort signal, both of which have the double speed, into signals having the normal speed (signals corresponding to the standard television signals), respectively. In other words, the clock frequencies are decreased by half. 
     The outputs from the first scanning conversion means  122  and the second scanning conversion means  123  are input to the signal synthesizing means  124 , and the inputs from these two series are output as an Smix signal of one series, whose dynamic range is enlarged. It is then input to the DSP  126  through the sixth switch  125 . The DSP  126  converts an input signal to a luminance signal and a color difference signal, for example, to output through the seventh switch  127 . 
     As described above, the signal whose dynamic range is enlarged can be obtained from two signals whose exposure times are different from each other. 
     (2) when the mode of successively picturing frames is selected 
     FIG. 12 is a block diagram illustrating a construction of the video camera  4  in the mode of successively picturing frames. 
     In this case, the progressive scanning CCD  111  performs the normal operation outputting the progressive scanning signals by the control means  129 . The progressive scanning signals which have the frame frequency of 60 Hz, each frame having 525 scanning lines (the number of the effective scanning lines is 480) are output from the progressive scanning CCD  111 . 
     Hereinafter, the operation of the video camera  4  in this mode is described. 
     The signals are progressively scanning output from the progressively scanning CCD  111 . Within each frame of the television signals (one frame={fraction (1/60)} sec.), only the signals of odd line are selected through the first switch  112  and input to the 1H delay means  113  to be delayed for one horizontal scanning period. The signals are then written in the first memory  117  through the second switch  115 . Similarly, only the signals of even line are selected through the switch  112  and the selected signals are written in the second memory  118  through the third switch  116 . 
     Here, the writing into the first memory  117  and the second memory  118  is performed every other frame, i.e., after writing for one frame, the writing for the next frame is not performed. 
     For the next two frames ({fraction (1/60)} sec.×2={fraction (1/30)} sec.), the signals output from the first memory  117  and the second memory  118  are added by the second adding means  119  to be output to the fifth switch  121  as an interlacing signal. 
     The first memory  117  and the second memory  118  repeatedly output the frame twice (twice of {fraction (1/60)} sec.) and the second adding means  119  performs adding, with the pair to be added shifted by one line for each frame. Therefore, it is output to the fifth switch  121  as a frame image of an interlacing signal. 
     The signal output from the fifth switch  121  is converted so as to have the normal signal speed by the second scanning conversion means  123  and converted to a proper standard television signal. It is then passed through the sixth switch  125  without passing through the signal synthesizing means  124  and is converted to a luminance signal and a color difference signal by the DSP  126  as a camera signal processing part to be output through the seventh switch  127 . 
     The signal output from the seventh switch  127  becomes two fields division interlacing output of video images by successive picturing frames of {fraction (1/30)} sec. 
     In this way, the frame processing is realized. 
     (3) when the mode of enlarging dynamic range of frame still image is selected 
     FIG. 13 is a block diagram illustrating a construction of the video camera  4  in the mode of enlarging the dynamic range for the frame still image. In this FIG. 13, to simplify the description, a shutter  142 , a shutter motor  140  driving the shutter  142 , and a diaphragm motor control means  141  controlling the shutter motor  140  are added to the video camera  4  shown in FIG.  10 . 
     FIG. 14 is a timing diagram showing the timing of the signal output from the progressive scanning CCD  111  when the dynamic range of the frame still images is realized in the video camera  4 . As shown in FIG. 14, in the video camera  4 , after exposure during {fraction (1/180)} sec., the Sshort signal is read out at timing T 3 , then after exposure during {fraction (1/90)} sec., the shutter is closed at timing T 4 , and the Slong signal is read out after the predetermined time. 
     Hereinafter, the operation of the video camera  4  in this mode is described. 
     First of all, the Sshort signals of one frame are progressively scanning output from the progressive scanning CCD  111  in the first field ({fraction (1/60)} sec.). Only signals of odd line are selected to be input to the 1H delay means  113  through the first switch  112 . The signals of odd line are written in the first memory  117  through the second switch  115  after being delayed by the 1H delay means  113  for one horizontal period. Similarly, only signals of even line are selected through the first switch  112  and written in the second memory  118  through the third switch  116 . 
     In the second field, the shutter motor  140  operates in accordance with the shutter control signal output from the diaphragm motor control means  141  and the shutter  142  switches from the open state to the close state, thereby shielding the light incident into the progressive scanning CCD  111 . As a result, the exposure operation of the progressive scanning CCD  111  is stopped. Next, the Slong signals of one frame are output from the progressive scanning CCD  111 , and only signals of odd line are selected through the first switch  112  and input to the 1H delay means  113  to be input to the first adding means  114  after being delayed for one horizontal scanning period. Similarly, only signals of even line are selected through the first switch  112  to be input to the first adding means  114 . In this case, the Slong signal is not written in the first memory  117  or the second memory  118 . 
     To perform the signal processing at a normal speed, as the driving of the progressive scanning CCD  11 , the Slong signal of one frame is divided into two fields, i.e., an upper half and a lower half of the display, whereby the signal processing is performed. 
     The Slong signal added in the line direction by the first adding means  114  is input to the fourth switch  120 . It is then input to the signal synthesizing means  124  after the predetermined scanning conversion is performed by the first scanning conversion means  122 . 
     On the other hand, the Sshort signals read out from the first memory  117  and the second memory  118  are input to the second adding means  119  and added in the line direction to be input to the fifth switch  121 . It is then input to the signal synthesizing means  124  after the predetermined scanning is performed by the second scanning conversion means  123 . 
     The Sshort signal and the Slong signal which are input to the signal synthesizing means  124  are both progressive scanning signals. The Slong signal and the Sshort signal which are input to the signal synthesizing means  124  are synthesized to become the Smix signal whose dynamic range is enlarged. 
     Next, the Smix signal is input to the DSP  126  as a camera signal processing part through the sixth switch  125  to be converted into the luminance signal and the color difference signal. As the still images of one frame, whose dynamic ranges are enlarged, through the third scanning conversion means  128  the odd lines of the luminance signal and the color difference signal which are output form the DSP  126  are written in the first memory  117  through the second switch  115 . And the third even lines thereof are written in the second memory  118  through the third switch  116 . 
     Then, the odd line is output from the first memory  117  and scanning converted by the first scanning conversion means  122  through the fourth switch  120  to be input to the seventh switch  127 . 
     On the other hand, the even line is output from the second memory  118 , scanning converted by the second scanning conversion means  123  through the fifth switch  121 , and passes through the DSP  126  through the sixth switch  125  to be input to the seventh switch  127 . 
     The signals input to the seventh switch  127  are switched between an odd signal and an even signal every field by the seventh switch  127  to be output as the frame still image whose dynamic range is enlarged. 
     The operation as described above is explained with a timing diagram shown in FIG.  15 . 
     In FIG. 15, the Sshort signal of one frame, which is progressively scanning output from the progressive scanning CCD  111 , is produced in field  1  (one field={fraction (1/60)} sec.). It is preferable to apply suitable SUB voltage to the progressive scanning CCD  111  to produce the Sshort signal. In field  1 , video images of the odd field are output from the first memory  117  and the second memory  118 . 
     When signal reading pulses CH 1  and CH 2  are given to the progressive scanning CCD  111  at the first timing in field  2 , the Sshort frame image is output for one field in field  2 . Among this, only odd lines are selected through the first switch  112  to be input to the 1H delay means  113 , and written in the first memory  117  through the second switch  115  after being delayed for one horizontal scanning period. Similarly, only even lines are selected through the first switch  112  and written in the second memory  118  through the third switch  116 . 
     In addition, the shutter control is performed in field  2 . In FIG. 13, while opening and closing of the diaphragm are explained as a shutter, a shutter device may be added in addition to the diaphragm. In field  2 , the shutter closes and the Slong signal is stored on the progressive scanning CCD  111 . 
     At the first timing of field  3 , CH 1  and CH 2  are applied again and the Slong signal is read out. The reading out of the Slong signal is performed for two field, i.e., field  3  and field  4 . The Slong signal of one frame which is progressively scanning output is synthesized with the Sshort signals which are read out from the first memory  117  and the second memory  118  by the signal synthesizing means  124 , and written in the space areas of the first memory  117  and the second memory  118  through the DSP  126 . After field  5 , the frame still image whose dynamic range is enlarged is successively output. 
     Here, an example in which the Sshort signal is read out earlier from the progressive scanning CCD  111  is shown. This is because the operation dispersion of the shutter device for producing the Slong signal is relatively larger and it is more preferable to produce the Sshort signal requiring high accuracy of time control by an electronic shutter. However the Slong signal can be produced by the shutter and the Sshort signal can be realized by the shutter device, on the contrary. 
     The progressive scanning processing in the dynamic range enlargement of the frame still image is described. 
     In the construction shown in FIG. 13, the processing at double speed is performed by the signal synthesizing means  124  and the DSP  126 . In this case, the frame still image of the Sshort signal is read out from the progressive scanning CCD in the first field to be stored in the first memory  117  and the second memory  118 . 
     Next, all the frame still images of the Slong are read out from the progressive scanning CCD  111  in the second field. The Sshort signal and the Slong signal are synthesized by the signal synthesizing means  124  at the double speed and processed by the DSP  126  at the double speed to produce the luminance signal and the color difference signal as the frame still image whose dynamic range is enlarged. 
     Then, the odd line is written in the first memory  117  through the second switch  115 , and even line is written in the second memory  118  through the third switch  116 . As a result, it becomes unnecessary to store a half display of the Slong signal on CCDs constituting the progressive scanning CCD  111  for one field, whereby superimposing of the dark current noise in the CCDs constituting the progressive scanning CCD  111  can be avoided. 
     Fifth Embodiment 
     Next, a video camera  5  which is constituted by adding a hand blurring correcting function to the above-described video camera  4  will be described with reference to the drawings as a fifth embodiment of the present invention. 
     FIG. 16 is a block diagram illustrating a construction of the video camera  5 , and the video camera  5  is characterized in that a motion detecting means  130  is added to the video camera  4  shown in FIG.  10 . 
     In FIG. 16, inputs into the first memory  117  and the second memory  118  are input to the motion detecting means  130 . In the motion detecting means  130 , motion vector information corresponding to hand blurring is obtained to be supplied to the first memory  117  and the second memory  118  as a memory control signal. In this case, as a construction of the motion detecting means  130 , the conventional method such as representative point matching method may be used. 
     Additionally, in the motion detecting means  130 , the construction in which the Slong signal and the Sshort signal are input, and motion are detected in each series to be synthesized, resulting in the motion vector information, or the construction in which one signal, preferably only Slong signal, is input, and the motion is detected, resulting in the motion vector information, may also be used. 
     In this case, the memory capacity can be saved by writing only hand blurring correction range which is previously predicted in the memory. Decreasing of the memory capacity is effective when the present invention is applied to a camera in PAL system having numerous vertical lines. In the fifth embodiment, the progressive scanning CCD  111  having pixel allowance for hand blurring is preferable. 
     Producing of signals to the memory for hand blurring allowance may be performed with respect to the horizontal direction, the vertical direction, or horizontal and vertical directions. 
     As described above, the video camera  5  according to the fifth embodiment of the present invention can realize the hand blurring correcting function which effectively utilizes the memory as well as the dynamic range enlargement.