JP2001086531A - Image video recording system and image reproduction system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image video recording system that records image information photographed by a high pixel density color camera on a videotape in compliance with the NTSC(national television system committee) system (or PAL system) without degrading the image quality and to provide an image reproduction system. SOLUTION: The video recording system that records an image photographed by a color camera 1 employing a single board color CCD onto a videotape 5 in compliance with the NTSC system, is provided with a multi-plane division section 2 that divides image information of one plane photographed by the color camera 1 and consisting of a plurality of sets of color information into image information sets by each color, a scan convert section 3 that converts the image information by each color that is multi-plane-divided into a signal in compliance with the NTSC system, and an identification information provision section 4 that adds identification information to the image information by each color converted by the scan convert section 3. The image information by each color to which the identification information is added is recorded on the videotape 5 in compliance with the NTSC system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single color CCD.
Images taken by a color camera using NTSC
The present invention relates to an image recording system and an image reproduction system for recording on a video of a (National Television System Committee) system or PAL (Phase Alternation by Line).

[0002]

2. Description of the Related Art In recent years, a color camera using a color single-chip CCD has been increased in the number of pixels, and for example, the number of pixels in the class of one million pixels is becoming common. An image captured by such a high-pixel-capable color camera is recorded on NTSC or PAL video (hereinafter sometimes referred to as NTSC video), which is versatile and cost-effective. In the NTSC or PAL format, recording using high pixels cannot be performed, and even an image taken in a state of a high pixel can be recorded only in a state where the image quality is reduced.

[0003]

In order to take advantage of the high pixel performance of a color camera, there is a method of recording on a commercial video tape used in a broadcasting station, but the cost is high. I will. There is also a method of digitizing and recording image information. However, since the amount of information becomes enormous with digitization, a moving image compression technique such as MPEG must be involved. In that case, even if a high-quality image is taken, if the recording / reproduction is performed using the compression technique, the image quality will be degraded.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to record image information captured by a high-resolution color camera on NTSC or PAL video without deteriorating image quality. An image recording system and an image reproducing system are provided.

[0005]

According to the present invention, there is provided an image recording system for recording an image photographed by a color camera using a color single-chip CCD into an NTSC or PAL video. A multi-plane division unit for multi-plane division of one-plane image information, which is captured by the color camera and includes a plurality of pieces of color information, into color-specific image information;
A scan conversion unit that converts the signal into a signal of the TSC system or the PAL system; and an identification information addition unit that adds identification information to the image information of each color converted by the scan conversion unit, wherein the identification information is added. It is characterized in that image information for each color can be recorded in NTSC or PAL video.

The operation of this configuration will be described in the NTSC system as follows. (1) An image is taken by a color camera using a single color CCD. A single color CCD has a mosaic color filter (for example, R, G, B) on the surface of the CCD pixel.
Is provided. One example of this is shown in FIG.

(2) The obtained image information includes a plurality (R,
G, B), which is divided into color-specific image information. In the above example, the image is divided into R-only image information, G-only image information, and B-only image information.
Here, in the above example, G information is obtained twice as much as R and B information, so G is divided into G1 and G2 (see FIG. 2). Therefore, in the above example, image information of one surface (which may be considered to correspond to one frame) is divided into four pieces of image information of each color.

(3) CCD for easy explanation
It is assumed that the number of pixels is 1.3 million (1280 × 960).
When this is divided into the above four planes, the number of pixels on the plane divided for each color is (640 × 480). The vertical scanning frequency (vertical transfer rate) of a general 1.3 million pixel class CCD is 7.5 Hz. Therefore, when divided into four planes as described above, the vertical scanning frequency for an image for each color is 30.
Hz (7.5 × 4 = 30). When the image information for each color is further halved in the vertical direction, the number of pixels is (640 × 240), and the vertical scanning frequency is also 60 Hz, which coincides with the field frequency of the NTSC system. In the NTSC system, one frame is divided into an odd field and an even field and interlaced scanning is performed. However, the number of effective scanning lines in each field is about 240, and the number of pixels in the vertical direction (resolution ) Almost matches. Therefore, by dividing one surface as described above, it is possible to match the format of the NTSC system.

(4) As described above, the image information of one plane is divided into multiple pieces of image information for each color, and the divided multi-plane image information is converted into an NTSC signal. As described above, since the image is converted in a state of being divided into multiple faces, the image quality does not deteriorate.

(5) Next, identification information is added to the image information for each color. This identification information is added to identify which color (R, G, B) the divided image information relates to. (6) Image information for each color to which identification information is added is NTSC
Record on video. That is, image information captured by a high-pixel CCD can be converted to NTS image data without deterioration in image quality.
It was possible to provide an image recording system for recording on a C type video.

As an embodiment of the present invention, the identification information is preferably added during a flyback period, whereby the identification information can be added without affecting the image information.

An image reproducing system for reproducing an image recorded by the image recording system according to the present invention, wherein the scan for A / D-converting the multi-plane divided image information reproduced by the NTSC video according to the color. The image processing apparatus further includes a converting unit and a one-plane combining unit that combines the image information in the A / D converted and multi-plane divided state into one-plane image information.

(7) To reproduce the image recorded by the above (1) to (6), (7) Since the image information reproduced from the video and divided into multiple planes for each color is an analog signal according to the NTSC system. , And A / D-convert it to a digital signal. (8) The multi-plane divided image information converted into a digital signal is combined with one-plane image information. This synthesized image information is equivalent to the image information output from the high pixel color camera, and there is no deterioration in image quality. By sending the synthesized image information to the color decoding unit and generating R, G, B signals, a high quality image can be displayed on a monitor or the like.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of an image recording system and an image reproducing system according to the present invention will be described with reference to the drawings. <Image Recording System> FIG. 3 is a schematic diagram showing a configuration of an image recording system according to the present invention. This image recording system is a high-pixel CCD using a single color CCD.
A camera 1 (hereinafter, simply referred to as a camera), a four-plane division unit 2 (corresponding to a multi-plane division unit) that divides image information captured by the camera 1 from one plane to four planes, and a four-plane division unit A scan conversion unit 3 for converting the converted image information into a signal of the NTSC system by a scanning line, an identification information addition unit 4 for adding identification information to the image information converted by the scan conversion unit 3, NTSC video 5 for recording the obtained image information.

Color single-plate CC used in camera 1
One example of D is conceptually shown in FIG. A color filter array is provided on the surface of the CCD pixel.
A (red) filter, a G (green) filter, and a B (blue) filter are arranged in a mosaic pattern. Where CCD
Is about 1.3 million pixels (1280 × 960). In order to record on the NTSC video 5 while utilizing the high pixel image information captured by the camera 1, the screen is divided in the four-plane division unit 2.

<Screen division> FIG.
4 conceptually shows a method of dividing the image into surface image information. In the color filter array, the number of G filters is twice as large as the number of R and B filters.
Consider _two filters, _one filter and G2 filter.
As shown in FIG. 2, divided 1 side image information of the (mosaic image) image information of R only, the image information of B only, the image information of only G _1, the image information of the four sides of the image information of only G ₂ I do. This dividing process is performed by the four-plane dividing unit 2.
In the division processing, image information is handled as digital data.

Here, the vertical scanning frequency of the CCD having 1.3 million pixels is 7.5 Hz to 15 Hz, but 7.5 Hz is generally used. When image information having 1.3 million pixels on one surface as shown in FIG. 4A is divided into four by color as described above, the divided image information has a resolution of 640 × 480, and as shown in FIG. The vertical scanning frequency for the divided surface is 30
Hz.

The NTSC signal has a field frequency of 5
At 9.94 Hz (≒ 60 Hz), the frame frequency = 1 /
2.times.field frequency (@ 30 Hz). An image of one frame (one surface) is formed by performing an interlaced scan of an image of one frame between an odd field and an even field.

Therefore, as shown in FIG. 4C, when the image information is further divided in half in the vertical direction, the number of pixels of the divided image information becomes 640 × 240, the vertical scanning frequency becomes 60 Hz, and the NTSC system Field frequency. In the figure, the subscript o indicates an odd field (Od
d), and the subscript e indicates an even field (Even). Although the field frequency of the NTSC system does not exactly match the vertical scanning frequency,
General NTSC equipment is designed to absorb the difference between 59.94 Hz and 60 Hz, and there is no problem. To explain this point in detail, in order to output at 59.94 Hz to the output side with respect to the input side speed of 60 Hz, the input image is output at a ratio of one image to the least common multiple of these values. It would be good to thin out.

In the NTSC signal, the number of effective scanning lines in each of the odd and even fields (the number of scanning lines useful for scanning the actual screen) is about 240. Therefore, the NTSC signal should be divided as shown in FIG. It can be said that the resolution matches the resolution in the NTSC system. As described above, 1
It has been clarified that the image information of the surface can be converted into an NTSC signal without deteriorating the image quality by dividing the image information of the surface into four pieces of image information of each color.

Next, a case where the vertical scanning frequency of the CCD of the camera 1 is 15 Hz will be described with reference to FIG. In this case, when the screen is divided as in FIG. 4, the frequency of one field is 120 Hz (the number of pixels is 640 × 240) as shown in FIG.
That is, since the speed on the input side is high and the speed on the output side is low, N
It can be matched to the TSC system. That is, (c)
As shown in (1), each field frequency is 60 Hz. Therefore, as shown in FIG. 5A, it is sufficient to thin out image information that is input in the order of # 1, # 2, # 3,... (# 2 is thinned out in FIG. 5). . This thinning is performed in the time axis direction and does not lower the resolution of the image information of one surface.

Returning to FIG. 3, the image information divided by the four-plane division unit 2 is D / A converted in the scan conversion unit 3, and is also converted into NTSC signals by scanning lines. N
The image information converted into the TSC signal is transmitted to the identification information adding unit 4.
To the NTSC video 5 with the identification information of R, B, G ₁ and G ₂ added thereto and recorded. The identification information is added to the vertical flyback period. Thus, NTSC
An image is recorded on the video 5 in a state of being divided into image information for each color. In addition, it is possible to record while maintaining the high resolution of the camera 1 using an inexpensive NTSC video tape.

<Image Reproduction System> Next, FIG. 5 shows a conceptual diagram of a system for reproducing an image recorded by the image recording system shown in FIG. The image reproduced by the NTSC video 5 is subjected to scan line conversion and A / D conversion in the scan converter 3. That is, the reproduced image information for each color is converted into digital information. This digital information is combined on one surface by the one-surface combining unit 6. That is, the image information divided into four surfaces in the image recording system of FIG. 3 becomes the image information of one surface again. The combination is performed based on the identification information added by the identification information adding unit 4. When combined on one surface, the color decoding unit 7 creates regular R, G, B signals and uses them for monitor display. In the color decoding section 7, an interpolation process of the image information is performed. The interpolation process will be briefly described. As shown in FIG. 2, the same type of color filters are arranged at intervals with respect to CCD pixels. Therefore, the image information about the portion where the color filter of that color does not exist is interpolated by predicting it from the surrounding image information.

The color decoding section 7 may be provided on the camera 1 side so far.
When a large number of cameras are used for surveillance, the same number of color decoding units as the number of cameras 1 existed. However, as shown in FIG. In the case of a large number of monitors, the cost of the camera head can be reduced.

<Surveillance System> In a surveillance system using a plurality of cameras for surveillance, a technique of sequentially switching and displaying the images of each camera on a monitor every few seconds is used. FIG. 7 shows an example of this configuration (prior art). In FIG. 7, three cameras A, B, and C are connected to the frame switcher 10. From camera A, images A1, A2, A3..., From camera B, images B1, B2, B3.
It is assumed that images C1, C2, C3,... Have been output. The frame switcher 10 switches images (frames) from the cameras A, B, and C every 1/60 second, for example, and rearranges the images as A1, B2, C3, A4, B5, C6,. Output to the time lapse video 11 at the subsequent stage.

The time lapse video 11 is for recording images while thinning out the transmitted images, thereby enabling long-time recording. For example, A1, B2, C
3, A4, B5, C6, A7, B8, C9, A10, B
When an image is sent as in 11, C12, A13, B14, C15,...
When recording in the order of 1, B2, C3, A10, B11, C12,..., The time that can be recorded on one video tape is tripled.

FIG. 8 shows an example in which the four-plane dividing unit 2, the scan converting unit 3, and the identification information adding unit 4 described in FIG. The cameras B and C are the same as before. Since the image information output from the camera A is divided into four planes, (A11, A12, A1
3, A14), (A21, A22, A23, A24)
... Also, from camera B, images B1, B
2, B3... Are output, and the camera C outputs an image C
1, C2, C3... Are output. Since the image output from the camera A is one set on four sides, the frame switcher 10 includes A11, A12, A13, A
14, B5, C6, B7, C8 (the above is for one set)
.., Etc. A function that can be switched is provided. As for the camera A, the number of frames to be thinned out in the time axis direction is larger than those of the other cameras B and C. However, since the pixels are not thinned out within the range of the image information of one surface, the image information maintains the high-resolution image quality obtained from the camera 1. Even if such thinning is performed, there is no problem in using the camera 1 for monitoring or measurement.

The image information output from the frame switcher 10 can be recorded for a long time by the time lapse video 11 (NTSC system). Of course, instead of the time-lapse video 11, it may be recorded in a normal NTSC video.

<Another Embodiment> When the number of pixels of the camera 1 becomes higher, the number of divisions of image information of one surface may be further increased. In this case, the number of frames to be thinned out in the time axis direction may be increased. That is, the number of divisions is not particularly limited in the present invention.

In the present embodiment, the description has been made of the NTSC system. However, the same configuration can be applied to the case of the PAL system.

[Brief description of the drawings]

FIG. 1 is a diagram conceptually showing a color single-chip CCD.

FIG. 2 is a diagram showing the concept of screen division.

FIG. 3 is a schematic diagram showing a configuration of an image recording system according to the present invention.

FIG. 4 is a diagram showing an example of scan conversion (part 1).

FIG. 5 shows an example of scan conversion (part 2).

FIG. 6 is a schematic diagram showing a configuration of an image reproduction system according to the present invention.

FIG. 7 is a configuration example in a monitoring system.

FIG. 8 is a configuration example of a monitoring system using the image recording system according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Camera 2 4-side division | segmentation part 3 Scan conversion part 4 Identification information addition part 5 NTSC video 6 Single-side synthesis part 7 Color decoding part

Continued on the front page F term (reference) 5C057 AA01 AA06 AA07 BA02 BA03 BB01 CC04 EA01 GF01 GF02 GF07 GJ01 GM01 GM08 5C063 AA02 AA03 AB01 AB07 BA03 CA01 CA09 CA14 CA16 CA38 DA07 5C065 AA01 BB30 CC17 GG30 GG30 GG30 GG30 GG49 HH01

Claims (3)

[Claims] 1. A recording system for recording an image photographed by a color camera using a color single-chip CCD into a video of an NTSC system or a PAL system, wherein the system is photographed by the color camera and comprises a plurality of color information. A multi-segment splitting unit for multi-segmenting the image information of the surface into image information for each color, and an NTSC or PA
A scan conversion unit that converts the signal into an L-type signal; and an identification information addition unit that adds identification information to the image information for each color converted by the scan conversion unit. NTS image information
An image recording system characterized in that recording can be performed on C-type or PAL-type video. 2. The image recording system according to claim 1, wherein the identification information is added during a blanking period. 3. An image reproduction system for reproducing an image recorded by the image recording system according to claim 1, wherein the image is divided into multiple planes for each color reproduced by the NTSC or PAL video. The scan conversion unit for A / D converting the image information; and
An image reproduction system, comprising: a one-plane synthesis unit that synthesizes image information of a plane.