JP4029752B2 - Video recording / playback system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a video recording reproducing system, and more particularly to high definition television system of the HDTV video recording reproducing system that outputs the high resolution video signal than the (horizontal 1920 pixels × vertical 1080 pixels) image.
[0002]
[Prior art]
A conventional high-definition video camera that performs high-definition imaging that is higher in resolution than HDTV images (horizontal 1920 pixels × vertical 1080 pixels) of a high-definition television system, for example, equivalent to horizontal 4000 pixels × vertical 2000 pixels, The moving image is obtained with a high-speed readout clock frequency using the high-definition image sensor. In this high-definition video camera, there is a method in which the pixels of the image sensor are divided and read into a plurality of blocks or lines, and the readout clock is relatively lowered to reduce the load on the image sensor and the signal processing circuit. Development of an extremely expensive dedicated system is required.
[0003]
On the other hand, it is configured to obtain a video signal having the same resolution as that of an HDTV image by using an inexpensive solid-state imaging device having the same number of pixels as that of a standard television system having a lower resolution than that of the HDTV system (high-definition system). Such video cameras are also known in the art (see, for example, Patent Document 1 and Patent Document 2).
[0004]
The conventional video camera described in Patent Document 1 provides four solid-state image sensors having the same number of pixels as that of the standard television system, and two of the solid-state image sensors divide incident light from the subject into two. In addition, two green lights obtained by wavelength selection are separately incident, and the remaining two solid-state image sensors are red light and blue light obtained by wavelength selection of incident light from the subject. The two solid-state imaging devices on which the green light is incident are arranged so that the pixel positions are shifted by one pixel in the vertical direction on the optical axis. A video camera that gets high resolution.
[0005]
In addition, the conventional video camera described in Patent Document 2 separates incident light from a subject into three primary color lights, and each of R, G, and B primary color lights has a plurality of pixels corresponding to an aspect ratio of a standard television system. And separately incident on a plurality of individual image sensors arranged so that the pixel positions in the vertical direction are in a specific positional relationship, and signal processing means from output primary color signals of the plurality of solid-state image sensors This configuration has a vertical resolution approximately twice that of the standard television system and generates an image signal with a horizontal scanning frequency of the HDTV studio standard.
[0006]
Further, in the conventional video camera described in Patent Document 2, for example, first to fourth four solid-state imaging devices are prepared, and a first solid-state imaging device that receives blue light and a second solid-state imaging device that receives red light. At least one of the solid-state imaging elements is at least half a pixel in the vertical direction relative to the third solid-state imaging element among the third and fourth solid-state imaging elements that receive the first and second green light. The third and fourth solid-state imaging devices are arranged so as to be shifted by a pitch and relatively shifted by at least one pixel pitch in the vertical direction.
[0007]
[Patent Document 1]
JP-A-6-269010 [Patent Document 2]
JP-A-9-163388
[Problems to be solved by the invention]
However, the method of developing a dedicated image sensor for obtaining a high-definition image has high technical difficulty and requires a large amount of development investment. In addition, a dedicated system is required for high-definition image transmission, recording / playback, and editing, resulting in an increase in development cost and a problem that the operation rate is reduced in operation.
[0009]
On the other hand, the conventional video cameras described in Patent Document 1 and Patent Document 2 have a problem that the resolution of the red signal and the blue signal can only be ½ that of the green signal. In particular, when a high-definition image dedicated projector is used to display a high-definition image, not only the green signal but also the three primary color signals of blue, red, and green must be photographed with the same resolution, so that the projector performance cannot be exhibited sufficiently.
[0010]
The present invention has been made in view of the above points, and has an inexpensive configuration and higher resolution than HDTV images (horizontal 1920 pixels × vertical 1080 pixels) of a high-definition television system, and all three primary color signals of blue, red, and green are present. It is an object of the present invention to provide a video recording / reproducing system using a video camera capable of obtaining a video signal obtained by imaging a subject with equal resolution.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, the video recording / reproducing system of the present invention splits an incident subject optical image into two parts, and the subject optical image divided into two by the parting means is separated into three primary color lights independently of each other. The first and second color separation optical means, and the first three primary color lights from the first color separation optical means to output the first image pickup signal and have the same number of pixels as the HDTV system The first image sensor has the same number of pixels as the first image sensor, and the pixel position is shifted relative to the pixels of the first image sensor by a ½ pixel pitch in both the horizontal and vertical directions. And a second image sensor that images the second primary color light from the second color separation optical means and outputs a second image signal, and is output from the first and second image sensors. Predetermined signal processing independently of each other for the first and second imaging signals. It outputs the first and second divided video signal by performing a first and second signal processing means synthesizes performing pixel interpolation to the first and second divided video signals input, HDTV Pixel interpolating means for outputting a video signal having a resolution higher than that of the system image, a first recording / reproducing apparatus for recording / reproducing the first divided video signal, and a second recording for recording / reproducing the second divided video signal The playback device and the first and second recording / playback devices are operated synchronously, and the first and second divided video signals recorded from the first and second recording / playback devices are played back in synchronization with each other to perform pixel interpolation. And a control device for supplying to the means .
[0014]
In the present invention, the first and second divided imaging reproduced from the inexpensive first and second recording / reproducing apparatuses for the HDTV system for recording and reproducing the first and second divided imaging signals having the same resolution as the HDTV system. A high-definition video signal can be output by interpolating and synthesizing the signals.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a block diagram of an embodiment of a video camera and a video recording / reproducing system according to the present invention. In the figure, a camera head 1 has two independent three-plate prism color separations obtained by dividing an optical image incident from a subject into two parts by a configuration described later, and by shifting pixels obliquely to each other. Using a two-dimensional sensor that is decomposed into three primary colors of red (R), green (G), and blue (B) by an optical system, and whose scanning line configuration corresponds to a standard HDTV signal (horizontal 1920 pixels × vertical 1080 pixels). The digital image data generated based on the three primary color signals having the same resolution as the HDTV image is generated.
[0016]
The camera control device 2 performs various controls of the camera head 1. Two systems of digital data generated by the camera head 1 are supplied to the pixel interpolation device 5 via coaxial cables or optical fibers 3 and 4, respectively. Two sets of digital data of 1920 pixels in the horizontal direction and 1080 pixels in the vertical direction are subjected to pixel interpolation by the pixel interpolating device 5, with 3840 (= 1920 × 2) pixels in the horizontal direction and 2160 (= 1080 × 2) in the vertical direction. ) It is converted into a high-definition video signal of pixels.
[0017]
This high-definition video signal is output to the high-definition video signal projector 6 capable of projecting 4000 pixels in the horizontal direction and 2000 pixels in the vertical direction, and projected onto the screen as a projector video. The digital data of the two video signals having the same resolution as the HDTV image input from the camera head 1 to the pixel interpolation device 5 bypasses the pixel interpolation device 5 and passes through the coaxial cables or optical fibers 7 and 8 as they are. Are supplied to recording / reproducing apparatuses 9 and 10 constituted by HDDs or VTRs, where they are recorded in parallel independently of each other.
[0018]
The recording / reproducing machine control device 11 controls the two recording / reproducing devices 9 and 10. Since the recording / reproducing apparatuses 9 and 10 are operated in synchronization with each other by the recording / reproducing apparatus control apparatus 11, video signals (HDTV video signals) having the same resolution as the two synchronized HDTV images are also obtained during reproduction. Can output. The two HDTV video signals reproduced in synchronization by the recording / reproducing devices 9 and 10 are supplied to the pixel interpolating device 5 via coaxial cables or optical fibers 7 and 8, where the pixels are interpolated to obtain 2 HDTV image signals. After being converted to a high-definition video signal with double resolution, it is supplied to the high-definition projector 6. Thereby, a high-resolution image is projected on the screen as a projector image.
[0019]
Next, the configuration and operation of each unit in FIG. 1 will be described in more detail. FIG. 2 shows a block diagram of an embodiment of the camera head 1 in FIG. In FIG. 2, incident light from a subject is incident on the camera head 1 via a taking lens 12. The taking lens 12 is a high-resolution lens for capturing an image of a subject. The light beam of incident light from the subject obtained by the taking lens 12 is divided into two light beams by the parallel-arranged relay lens optical system 13 in the camera head 1 without depending on the wavelength. The light enters the optical system 14a and the second system prism optical system 15a.
[0020]
The first system prism optical system 14a and the second system prism optical system 15a are color separation optical systems that separate incident light into three primary color lights, respectively. The light enters the imaging element 15b independently of each other. Each of these image sensors 14b and 15b includes three HDTV solid-state image sensors (for example, CCD or CMOS).
[0021]
FIG. 3 shows a configuration diagram of an optical system from the taking lens 12 to the image sensors 14b and 15b. In the figure, the same components as those in FIG. In FIG. 3, the parallel arrangement relay lens optical system 13 includes a dichroic mirror 131 and a total reflection mirror 132, and divides an optical image incident through the taking lens 12 into two light beams by the dichroic mirror 131. One light beam passes through the dichroic mirror 131 and enters the first system prism optical system 14a. The other light beam is reflected by the dichroic mirror 131, then enters the total reflection mirror 132, and is totally reflected here. Thus, the direction of the light beam is changed by 90 ° and enters the second system prism optical system 15a.
[0022]
The first system prism optical system 14a and the image sensor 14b, and the second system prism optical system 15a and the image sensor 15b have the same configuration, for example, the configuration shown in FIG. In the figure, the first and second system prism optical systems 14a and 15a are arranged such that a B prism 31 for extracting a blue (B) light component from incident light and a red (from the light transmitted through the dichroic film 32 from the B prism 31). R) includes an R prism 33 for extracting light components and a G prism 35 for extracting green (G) light from the light transmitted from the R prism 33 through the dichroic film 34.
[0023]
The imaging device 14b (15b) includes a blue light solid-state imaging device 36B on which blue light reflected and extracted from the dichroic film 32 and the incident surface of the B prism 31 from the B prism 31, respectively, and a dichroic film 34. And red light solid-state image sensor 36R into which red light reflected and extracted by the incident surfaces of the R prism 33 is incident, and green light solid-state image sensor 36G into which green light transmitted through the G prism 35 enters. Consists of.
[0024]
The solid-state imaging devices 36B, 36R, and 36G are each configured by a CCD or a CMOS, and are, for example, HDTV imaging devices having a two-dimensional imaging area composed of 1920 pixels in the horizontal direction and 1080 pixels in the vertical direction. Further, the three solid-state image pickup devices 36B, 36R, and 36G constituting the image pickup device 14b and the three solid-state image pickup devices 36B, 36R, and 36G constituting the image pickup device 15b have a pixel pitch in both the horizontal direction and the vertical direction. (This is referred to as 1/2 diagonal pixel shift) and is mechanically arranged precisely. In an HDTV image sensor, the pixel pitch is usually 5 μm, and in this case, 2.5 μm corresponds to a ½ pixel pitch.
[0025]
Thereby, in the vertical direction, each line of the image sensor 15b is positioned between each line of the image sensor 14b, so that the number of lines as a whole is twice that of the HDTV system, which is about twice the vertical resolution of the HDTV system. Vertical resolution can be obtained. Also, in the horizontal direction, each pixel of the image sensor is located between each pixel of the image sensor 14b, so that the number of pixels in the horizontal direction as a whole is approximately doubled, and the horizontal resolution is improved approximately twice. Can do.
[0026]
Referring back to FIG. 2 again, the first three primary color signals having the same resolution as HDTV images taken out in parallel from the three solid-state image sensors for HDTV constituting the image sensor 14b are the first process circuit. At the same time, the second three primary color signals having the same resolution as HDTV images taken out in parallel from the three HDTV solid-state image sensors constituting the image sensor 15 b are supplied to the second process circuit 17. To be supplied.
[0027]
The process circuits 16 and 17 perform the same process processing as the normal three-plate camera, such as gamma correction and black level correction, on the input three primary color signals. The first process circuit 16 and the second process circuit 17 perform basically equivalent operations. However, in order to correct variations in the two optical systems 14a and 15a and the image sensors 14b and 15b, the second process circuit 16 A correction value 17 is given by a central processing unit (CPU) 20 by a correction table. A synchronization signal generator (SSG) 21 is a synchronization signal generator of the camera and supplies a synchronization signal to the process circuits 16 and 17. The PS 22 is a power supply device that supplies a necessary DC voltage to each unit.
[0028]
Here, the basic configuration of the first process circuit 16 and the second process circuit 17 is the same, for example, as shown in the block diagram of FIG. In the figure, the same components as those in FIGS. 2 and 4 are denoted by the same reference numerals. In FIG. 5, an R signal and a G signal respectively extracted from an R image sensor (red solid-state image sensor) 36R, a G image sensor (green solid-state image sensor) 36G, and a B image sensor (blue solid-state image sensor) 36B. , B signals are supplied to the black level correction circuits 41R, 41G, 41B to correct the black level to a predetermined level, and then supplied to the gamma correction circuits 42R, 42G, 42B to perform known gamma correction.
[0029]
Further, the R signal, G signal, and B signal extracted from the gamma correction circuits 42R, 42G, and 42B are supplied to the knee correction circuits 43R, 43G, and 43B and subjected to known knee correction, and then commonly used in the matrix circuit 44. The supplied luminance signal (Y signal) and two kinds of color difference signals RY and BY are converted and output based on a predetermined matrix arithmetic expression. The black level correction circuits 41R, 41G, and 41B, the gamma correction circuits 42R, 42G, and 42B, and the knee correction circuits 43R, 43G, and 43B perform a correction operation based on a control signal from the CPU 20.
[0030]
Returning to FIG. 2 again, the video signal (Y signal, RY signal, and BY signal in the example of FIG. 5) extracted from the process circuit 16 of the first system, and the second system The video signals extracted from the process circuit 17 (Y signal, RY signal, and BY signal in the example of FIG. 5) are HDTV video signals having the same resolution as that of the HDTV image, and are sent to the interface circuits 18, 19, respectively. After being supplied and converted into a predetermined signal form, it is output to the outside in synchronization with each other. Here, the signal form includes an SDI (serial digital interface) signal, a parallel digital signal, an analog signal, and the like depending on the configuration of the interface circuits 18 and 19.
[0031]
In this manner, the two video signals (digital data) output from the camera head 1, each having 1920 pixels in the horizontal direction and 1080 pixels in the vertical direction, are subjected to pixel interpolation by the pixel interpolation device 5 in FIG. Thus, the high-definition video signal is converted into 3840 (= 1920 × 2) pixels in the horizontal direction and 2160 (= 1080 × 2) pixels in the vertical direction.
[0032]
The pixel interpolation operation by the pixel interpolation device 5 will be described in more detail with reference to FIG. In FIG. 6, AN and AN + 1 are the Nth and N + 1th lines of the first field of the first HDTV video signal (digital data) A output from the interface circuit 18 in the camera head 1 in 2: 1 interlace scanning. BN, BN + 1, and BN + 2 are N lines in the second field of the second HDTV video signal (digital data) B output from the interface circuit 19 in the camera head 1 in 2: 1 interlace scanning, N + 1. The first and N + 2th scanning lines, and FIG. 6 shows the state of pixel interpolation during the first field scanning.
[0033]
6, black circles an, 1, an, 2,... On the scanning line of the first field in FIG. 6 indicate pixels of the image sensor 14b on the scanning line AN, and black circles an + 1, 1, an + 1, 2, ... Represent pixels of the image sensor 14b on the scanning line AN + 1. Similarly, hatched circles bn, 1, bn, 2,... On the scanning line of the second field in FIG. 6 indicate pixels of the image sensor 15b on the scanning line BN, and circles bn + 1,1. , Bn + 1,2,... Indicate pixels of the image sensor 15b on the scanning line BN + 1, and circles bn + 2,1, bn + 2,2,. Indicates a pixel.
[0034]
As described above, the pixels of the image pickup device 14b and the pixels of the image pickup device 15b are arranged so as to be shifted from each other by ½ diagonal pixels shifted by ½ pixel pitch (2.5 μm) in the vertical direction and the horizontal direction. As shown in FIG. 6, the pixel position on the scanning line of the first field and the pixel position on the scanning line of the second field are arranged with a shift of ½ pixel in both the horizontal direction and the vertical direction.
[0035]
Among these input HDTV video signals A and B, the pixel interpolator 5 performs two adjacent pixels in the horizontal direction on the same first scanning line of the HDTV video signal A (for example, an, 1 and an, 2) and two pixels (for example, bn, 1 and bn + 1,1) adjacent in the vertical direction on the two scanning lines of the HDTV video signal B adjacent to the first scanning line. The average value of the signal values of a total of four pixels is generated as an interpolated pixel on the first scanning line (cn, 1 in the above example).
[0036]
Similarly to the above, during the second field scanning, two pixels adjacent to the horizontal direction on the same second scanning line of the HDTV video signal B and 2 of the HDTV video signal A adjacent to the second scanning line are also obtained. An average value of signal values of a total of four pixels of two pixels adjacent in the vertical direction on one scanning line is generated as an interpolation pixel on the second scanning line.
[0037]
In this way, by performing real-time pixel interpolation that generates one interpolated pixel from four pixels adjacent in the horizontal and vertical directions by the pixel interpolator 5 using the two systems of HDTV video signals A and B, respectively. Thus, a high-definition image signal equivalent to 3840 pixels in the horizontal direction and 2160 pixels in the vertical direction, which is twice the horizontal and vertical pixels of the HDTV image, can be obtained.
[0038]
As described above, according to the present embodiment, the high-definition image signal equivalent to 3840 pixels × 2160 pixels obtained by interpolation by the pixel interpolating device 5 has the same resolution for all the R, G, and B primary color signals. Since it is the generated image signal, the high-definition projector 6 can display on the screen a high-definition image that sufficiently exhibits the performance of the projector.
[0039]
In addition, according to the present embodiment, the two video signals transmitted on the coaxial cable or the optical cables 7 and 8 by bypassing the pixel interpolation device 5 are standard HDTV video signals. It is possible to transmit using two systems of device and transmission channel.
[0040]
In the present embodiment, the HDTV video signal can be recorded by using the two video recording / reproducing devices 9 and 10 that perform the synchronous operation by the recording / reproducing device controller 11, and in the case of reproduction, the synchronous operation is performed. The output HDTV video signals of the two video recording / reproducing devices 9 and 10 are subjected to pixel interpolation in addition to the pixel interpolating device 5 in the same manner as the video signals from the camera head 1, so that the resolution is twice as high as that of the HDTV image. Video signals can be output.
[0041]
Furthermore, in the present embodiment, the video signal of one system recorded in the recording / reproducing devices 9 and 10 is a normal HDTV video signal, so that it can be edited with editing equipment for HDTV. Then, by editing the HDTV video signal of the other system based on the editing point information determined in the editing process at this time, editing of the high-definition video signal can be performed using the editing equipment for HDTV as it is. Become. Moreover, since the HDTV video signal program can be obtained by using either one of the HDTV video signals as they are, a high-definition video signal and an HDTV video signal can be obtained simultaneously.
[0042]
The present invention is not limited to the above embodiment. For example, the camera head 1, the camera control device 2, the pixel interpolation device 5, the recording / reproducing devices 9 and 10, the recording / reproducing device control device 11 and the like are individually provided. Even if it is not provided, it is possible to appropriately change the configuration, such as combining these devices or integrating them into several devices. In the above embodiment, the pixel interpolation is described as interpolating from the four surrounding pixels. However, the present invention is not limited to this, and other known interpolation methods such as taking an average value of the surrounding eight pixels are used. Application is also possible.
[0043]
【The invention's effect】
As described above, according to the present invention, the first and second pixels having the same number of pixels as the HDTV system and the pixel positions relatively shifted by ½ pixel pitch in both the horizontal and vertical directions are arranged. A subject optical image divided into two parts is separately incident on the second image sensor to obtain first and second image signals, which are converted into first and second divided video signals through signal processing means, and then pixel interpolation Since the video signal is synthesized and output to output a higher definition video signal than the HDTV system image, the conventional HDTV camera process circuit and synchronization signal circuit can be used as they are. Development is unnecessary, the development period can be shortened, and high-definition video signals can be easily obtained.
[0044]
Further, according to the present invention, the high-definition video signal obtained by pixel interpolation is an image signal in which all the three primary color signals are generated with the same resolution. Therefore, the high-definition projector sufficiently exhibits the performance of the projector. Images can be displayed on the screen.
[0045]
Furthermore, according to the present invention, the first and second reproduced from the inexpensive first and second recording / reproducing apparatuses for the HDTV system for recording and reproducing the first and second divided imaging signals having the same resolution as the HDTV system. Since the two divided imaging signals are interpolated and synthesized to output a high-definition video signal, transmission using two channels of an HDTV transmission system that has been proven sufficiently reliable can be easily performed. Low-cost and highly reliable recording / reproduction can be realized.
[Brief description of the drawings]
FIG. 1 is a block diagram of an embodiment of the present invention.
FIG. 2 is a block diagram of an embodiment of the camera head in FIG.
3 is a configuration diagram of an example of a parallel arrangement relay lens optical system in FIG. 2; FIG.
4 is a configuration diagram of an example of a first system, a second system prism optical system, and an image sensor in FIG. 2;
5 is a block diagram of an example of a process circuit in FIG. 2. FIG.
6 is an explanatory diagram of a pixel interpolation operation by the pixel interpolation device in FIG. 1. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Camera head 2 Camera control apparatus 5 Pixel interpolation apparatus 6 High-definition projector 9, 10 Recording / reproducing apparatus 11 Recording / reproducing apparatus control apparatus 13 Parallel arrangement relay lens optical system 14a First system prism optical system 14b, 15b Image sensor 15a Second system Prism optical system 16, 17 Process circuit 18, 19 Interface circuit 20 Central processing unit (CPU)
36R Solid-state image sensor for red light 36G Solid-state image sensor for green light 36B Solid-state image sensor for blue light

Claims (1)

Dividing means for dividing the incident subject optical image into two parts;
First and second color separation optical means for separating the subject optical image divided into two by the division means into three primary color lights independently of each other;
A first imaging device having the same number of pixels as the HDTV system, which images the first three primary color lights from the first color separation optical means and outputs a first imaging signal;
The number of pixels is the same as that of the first image sensor, and the pixel position is relatively shifted with respect to the pixels of the first image sensor by a ½ pixel pitch in both the horizontal and vertical directions. A second image sensor that images the second primary color light from the second color separation optical means and outputs a second imaging signal;
The first and second imaging signals output from the first and second imaging elements are subjected to predetermined signal processing independently of each other to output first and second divided video signals. First and second signal processing means;
Pixel interpolation means for performing pixel interpolation on the input first and second divided video signals and combining them to output a video signal having a higher resolution than the HDTV image ;
A first recording / reproducing apparatus for recording / reproducing the first divided video signal;
A second recording / reproducing apparatus for recording / reproducing the second divided video signal;
The first and second recording / reproducing devices are operated synchronously, and the first and second divided video signals recorded from the first and second recording / reproducing devices are synchronously reproduced and the pixel interpolation is performed. A control device to supply the means;
A video recording / reproducing system comprising:

Images