JP3094428B2 - Video signal recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in the following order.

Means F acts G Example G ₁ 8 millimeter video Standard Description G ₂ video camera image for Solving the Problems E issues Summary C ART D invention FIELD B invention on A industry is to Solve Description of recording / reproducing unit G ₃ Description of audio recording / reproducing unit of video camera G ₄ Description of recording / reproducing unit of still image G ₅ Description of modified example H Effect of the invention A Industrial application field The present invention relates to a video signal recording device suitable for application to a color VTR.

B SUMMARY OF THE INVENTION The present invention is, for example, in a video signal recording device suitable for application to a camera-integrated VTR, while continuously recording a video signal continuously obtained by shooting or the like as a moving image,
In parallel with this recording process, a still image signal obtained from a video signal is recorded at an arbitrary timing, so that recording of a moving image and a still image can be performed simultaneously. An ID signal indicating the end portion is recorded in the end portion so that the end portion can be easily searched.

C. Related Art Conventionally, a so-called electronic still camera that records a still image as an electric video signal on a magnetic disk has been developed. According to this electronic still camera, there is an advantage that, unlike a camera using a general silver halide film, processing such as development is not required, and a photographed still image can be immediately viewed simply by connecting to a television receiver.

D Problems to be Solved by the Invention However, still images shot by such an electronic still camera generally have lower resolution than still images shot by using a silver halide film, and an electronic image capable of shooting still images with higher resolution. Development of a still camera was requested. In this case, the size of the magnetic disk as a recording medium is limited, and there is a limit to the improvement in resolution using the magnetic disk.

For this reason, using a semiconductor memory as a recording medium, a video signal of a still image obtained by shooting is converted into a digital signal,
An electronic still camera has been developed in which this digital video signal is stored in a semiconductor memory for recording, and a high-resolution still image can be obtained. Cost was high, and it was used only for business use. On the other hand, video tape recorders (VTRs) have become widespread as consumer video equipment, and it has been demanded that high-resolution images can be recorded using the VTRs.

For this reason, the present applicant has previously disclosed in Japanese Patent Application No. 2-46816 such that a 1-field or 1-frame digital video signal is recorded in a PCM audio data recording section of a VTR in a format called 8 mm video. Suggested what was done. In this case, a digital video signal of one field or one frame is recorded in a PCM audio data recording unit of several tens to several hundred tracks. By recording a digital video signal in this manner, a high-resolution still image can be efficiently recorded.

By the way, if a digital video signal constituting one still image is recorded over a plurality of tracks,
When recording a video signal of another still image on an unrecorded portion of a tape on which a video signal of a still image has already been recorded, the end of the video signal already recorded is detected, and a new end is recorded following this end. It is necessary to record a video signal of a simple still image. Otherwise, a new video signal may be recorded on a track on which a video signal of a still image has already been recorded, and a previously recorded signal may be erroneously erased.

However, if the end portion of the still image signal recorded over several hundred tracks is searched for by normal reproduction, there is a disadvantage that it takes a very long time to detect this end portion.

An object of the present invention is to make it possible to easily detect the end of a still image signal already recorded in a recording apparatus that performs this type of still image recording.

E. Means for Solving the Problems The present invention is directed to a video signal recording apparatus which continuously records video signals obtained continuously as a moving image and records a still image signal obtained from the video signal at an arbitrary timing. In the apparatus, an ID signal indicating an end portion is recorded following the still image signal near the end or end portion of the still image signal recording unit, and a new recording medium on which the still image signal has already been recorded is newly recorded. When a still image signal is recorded, a still image signal is recorded following the ID signal.

F function By doing so, by searching for an ID signal indicating the end point by a search or the like, a moving image and a still image can be efficiently and simultaneously recorded on a recording medium such as a magnetic tape.

G Example Hereinafter, an example of the present invention will be described with reference to the accompanying drawings.

In the description the example of a standard G ₁ 8 mm video, obtained by using a video camera 8 mm video tape recorder called standard, first the 8
The standard of the millimeter video tape recorder will be described.

According to this standard, recording and reproduction are performed using a pair of rotary heads provided at an angular interval of 180 degrees from each other, and the tape is wound around a 221-degree range on the rotating surface of the head. The video signal is recorded / reproduced in the 180 degree section of the 221 degrees, and the digital (PCM) and time axis compressed audio signal is recorded / reproduced in the remaining 36 degree section. It has become.

That is, FIG. 3 shows a format of a recording track on a tape according to the above-described standard. From the right side where the head starts to contact the tape, first, a rush portion (51) corresponding to a rotation angle of the head of 5 degrees is provided at the front end. A clock run-in section (52) that synchronizes with PCM data, which will be described later, is provided during the latter half of the entry section (51) of 2.06 degrees (corresponding to three horizontal periods (H) of the video signal). Following this run-in part (52), the PCM data part (53) of the time-base compressed audio signal is 26.32
Provided in degrees. 2. Following this data section (53)
The 06 ° (3H) period is used as a back margin part (54) for a recording position shift or the like during after recording, followed by a guard part between the 2.62 ° video part and the PCM data part (5).
5) is provided. Following the guard section (55), a video signal section (56) for one field is provided over 180 degrees. After this, the separation part for 5 degrees (57)
Is provided.

Therefore, in this standard, after a video signal of one field is recorded and reproduced by the video signal part (56), an audio signal for 1/60 seconds during this period is converted to PCM and subjected to processing such as error correction. , Is compressed to about 1 / 6.8 on the time axis, and is recorded and reproduced in the PCM data section (53). The recording tracks are sequentially provided diagonally in the longitudinal direction of the tape, and continuous video signals and audio signals are recorded and reproduced.

By the way, in the above standard, the video signal part (56)
Dividing 180 degrees into 5 equals makes each 36 degrees. On the other hand, when the PCM data part (53), the rush part (51), 5 degrees, the subsequent back margin part (54), 2.06 degrees, and the guard part (55), 2.62 degrees, are exactly 36 degrees. Therefore, it has been proposed to form a recording / reproducing device dedicated to an audio signal by using a device of the above-mentioned standard.

FIG. 4 shows an example of a recording track format for that purpose. In the figure, the portion from the entry portion (51) on the side where the head starts to contact to the guard portion (55) is equivalent to the above standard, and this section is the first segment. Next, a rush portion (61), a run-in portion (62), a data portion (63), a margin portion (64), and a guard portion (65) having the same configuration as described above are provided from the start end side of the conventional video signal portion (56). , This section is the second segment. Further, a configuration similar to that of the second segment is repeatedly provided for every 36 degrees of the video signal portion (56), and is set as the third to sixth segments, respectively.
After this, a separation portion (57) for 5 degrees is provided.

Thereby, the first to sixth six segments are provided. Then, for each of these segments, the rotational angle position of the rotary head is detected, and PCM data is output at a time corresponding to a desired segment (section) of 36 degrees from the head end side of the head and recorded. At the same time, by performing the reproduction by gating the time of the reproduction signal, each segment can be recorded and reproduced independently. When re-recording is performed on a tape that has been used once, a so-called flying erase head is used to drive only the time when the head is in contact with a section of a desired segment, so that only that section is selectively performed. And can be re-recorded.

In this way, the PCM audio signal can be recorded and reproduced independently for each section of the tape divided into six in the width direction,
For example, using a tape that can be recorded for 4 hours
It can record and play back PCM audio signals for 24 hours.

G in ₂ video camera The present example of the video recording and reproducing unit of obtained by this third view and 8 mm video tape recorder standard for video camera shown in FIG. 4, constituting as shown in FIG. 1 . In this FIG.
(1) shows a CCD imager as a solid-state image sensor,
This CCD imager (1) is a so-called all-pixel reading type (Japanese Patent Laid-Open No. 1-188179) in which an image signal of an odd-numbered horizontal line and an image signal of an even-numbered horizontal line can be individually read out.
No.). This all-pixel readout type
The CCD imager (1) is, for example, as shown in FIG.
A color filter array comprising 494 (vertical) x 768 (horizontal) color filters of e, green G, cyan Cy, etc. is arranged, and each color filter of this color filter array is a CCD imager (1).
The signal charge based on the color light passing through each color filter is stored in each light receiving element in correspondence with the light receiving element arranged on the front surface of the light receiving element.

Then, the signal charges accumulated in the light receiving elements of the odd horizontal lines and the signal charges accumulated in the light receiving elements of the even horizontal lines are output from the other shift registers (1a) and (1b),
The outputs of the shift registers (1a) and (1b) are supplied to output circuits (2) and (3). Each of the output circuits (2) and (3) performs an output process such as sample hold, and outputs the image signals output from the output circuits (2) and (3) to the analog / digital converters (4) and (5). Supply and convert to digital imaging signal. Then, the digital imaging signals output from the analog-to-digital converters (4) and (5) are supplied to the imaging signal processing circuits (6) and (7), and the imaging signal processing circuits (6) and (7) A luminance component and a color difference component are extracted from the supplied image signal. In this case, when the number of horizontal lines of the image signal is n, the imaging signal processing circuit (6) the luminance component Y _n and color difference components (R-Y) _n, (B-
Y) _n, and the image signal processing circuit (7) extracts the luminance component Y _{n + 263} and the color difference components (RY) _{n + 263} and (BY) _{n + 263.}
And extract In other words, the output of the imaging signal processing circuit (6) and the output of the imaging signal processing circuit (7) are temporally and simultaneously output with signals shifted by 263 horizontal lines corresponding to one field. Therefore, when the image signal processing circuit (6) outputs the luminance component and the color difference component of the video signal of each line in the odd field, the image signal processing circuit (7) outputs the luminance of the video signal of each line in the even field. When the luminance component and the color difference component of the video signal of the even field are output from the imaging signal processing circuit (6), the video signal of the odd field is output from the imaging signal processing circuit (7). Is output.

Then, the output Y _{n of} the video signal processing circuit (6), (R−
Y) _n and (BY) _n are supplied to digital-to-analog converters (8), (9) and (10), respectively, converted into digital signals, and then supplied to a video signal processing circuit (11). The video signal processing circuit (11) converts a video signal supplied as a luminance component and a color difference component into a video signal of a predetermined standard for recording, and converts the video signal via a RF circuit (12) to a rotating head drum. Is supplied to the magnetic head (13) mounted on the video tape (14), and is recorded on the video signal portion (56) of the standard track as shown in FIG. 3 formed on the video tape (14). In this case, a video signal is recorded one field at a time on one track.

The video signal reproduced from the video tape (14) by the magnetic head (13) is supplied to the video signal processing circuit (11) via the RF circuit (12), and the reproduced video signal is transmitted from the video signal processing circuit (11). Supply the signal to the output terminal (15).

In the description and the example of the voice recording and reproducing unit of G ₃ camcorder, an audio signal picked up microphone (not shown) supplied to the terminal (21) is supplied to a noise reduction circuit (22), this After performing noise reduction by the noise reduction circuit (22), the noise reduction circuit (22) supplies the analog signal to the analog-to-digital converter (23). The analog-to-digital converter (23) converts the audio signal into a digital signal. To the first fixed contact (24a). This switch (24) is used to connect the movable contact (24m) to the first fixed contact (24a) during digital audio signal recording / reproduction.
A signal obtained at the movable contact (24m) is supplied to a digital data processing circuit (25), and the digital data processing circuit (25) performs predetermined processing such as addition of an error correction code. After that, the data is supplied to a magnetic head (13) via an RF circuit (12), and is recorded on a PCM data portion (53) of a standard track as shown in FIG. 3 formed on a video tape (14).

The digital audio signal reproduced from the video tape (14) by the magnetic head (13) is supplied to the digital data processing circuit (25) via the RF circuit (12), and the digital data processing circuit (25) After performing correction and the like, it is supplied to a digital / analog converter (26) via a changeover switch (24). And this digital-analog converter (2
After being converted to an analog audio signal in 6), noise reduction is performed in a noise reduction circuit (22), and the processed audio signal is output from an audio signal output terminal (27).
Although not shown, the audio signal is also subjected to frequency multiplexing recording of the FM-modulated signal and the video signal, and the above-described recording of the digital audio signal is provided as an option, and is recorded as necessary.

G ₄ Explanation of still image recording / playback unit In this example, a digital video signal of a still image is recorded instead of a digital audio signal in the PCM data unit (53) where the digital audio signal is recorded in this manner. I can do it. That is, when in the still image recording mode, the luminance component and the color difference component (digital signal) of the video signal output from the imaging signal processing circuits (6) and (7) are supplied to the bit reduction circuit (31). After the data redundancy is reduced to a fraction by the bit reduction circuit (31), the data is supplied to the frame memory (32) and written at a predetermined timing. This writing is performed separately for the luminance component Y and the color difference components (RY) and (BY). In this case, the writing and reading of the frame memory (32) are controlled by the memory controller (33), the writing is performed by operating the still image recording switch (42) of the video camera, and the image signal processing circuit (6) and the imaging signal processing circuit (6). Since a video signal shifted by one field is output from the signal processing circuit (7), the output of the two processing circuits (6) and (7) is combined into a video signal for one frame to generate a frame memory (32). ). In the bit reduction circuit (31), the information amount of the video signal is not changed only by reducing the data redundancy.

Then, the video signal for one frame once stored in the frame memory (32) is read out at a relatively low transmission rate according to the above-described transmission rate of the digital audio signal under the control of the memory controller (33), and is read out serially. The data is supplied to a parallel conversion circuit (34), and is converted into serial data by the serial / parallel conversion circuit (34). Then, the serial data output from the serial / parallel conversion circuit (34) is supplied to the second fixed contact (24b) of the changeover switch (24). Here, when reading from the frame memory (32), the movable contact (24m) of the changeover switch (24) is connected to the second fixed contact (24b), and the serial / parallel conversion circuit (34) The serial data to be output is supplied to a digital data processing circuit (25). Then, the digital data processing circuit (25) performs predetermined processing such as addition of an error correction code in the same manner as when recording a digital audio signal, and supplies the processed data to a magnetic head (13) via an RF circuit (12).
A video signal for one frame is recorded as a still image signal in a PCM data section (53) of a standard track as shown in FIG. 3 formed on a video tape (14).

In this case, the PCM data part of one track (53)
Since the capacity that can be recorded on a single track is small, a video signal for one frame is recorded on a plurality of tracks. For example, when recording a digital audio signal in the PCM data section (53) of one track, it is assumed that recording is performed at a transmission rate of 500 kBPS (that is, recording of 500 kbits per second), and the imaging signal processing circuit (6) and It is assumed that the video signal for one frame output by (7) has 7.6 Mbits in total of luminance and color difference. Then, assuming that 1/4 compression is performed in the bit reduction circuit (31), the frame memory (32) stores 1.9 M bits as a video signal for one frame. 500k of this 1.9M bit signal
When recording at the BPS transmission rate, 1900 ÷ 500 = 3.8, and the video signal for one frame in 3.8 seconds is converted into the PCM data part (5
Recorded in 3). This 3.8 seconds is equivalent to 228 tracks.

Hereinafter, a description will be given assuming that a video signal of one frame is recorded on the 288 tracks.

In this example, an ID signal (hereinafter, referred to as a start point ID) indicating the start point is recorded in the first 20 tracks of the 228 tracks constituting the video signal for one frame, and the last 20 tracks are recorded. An ID signal indicating the end point (hereinafter, referred to as an end point ID) is recorded at the end. That is, as shown in Figure 5, when one frame of video signal is to be recorded by the PCM data of the track t ₁ to the track t ₂₂₈ (53), the first 20 tracks t ₁ ~t
Record the start point ID to _20, the first of 20 track t
₂₀₉ records the end point ID in the ~t _228.

The reason that each ID is recorded on 20 tracks at a time is to enable the ID to be detected at the time of high-speed search (search by fast forward or rewind up to 20 times speed).

In the present embodiment, the video data to be recorded on each track t ₁ ~t _228, adds the track number data as a sub code in order to record the track number data together with digital video signals.

Then, for example, already one frame videotape digital video signal is recorded in the PCM data portion of the track t ₁ ~t ₂₂₈ (53), when recording digital video signal of a newly still image, CCD imager (1 1) imaged
After once it is stored in the frame memory (32) a video signal of a frame, looking for the endpoint ID recorded with a digital video signal to the track t ₂₀₉ ~t ₂₂₈ at a high speed search.

In this case, for example, the head track is scanned during the imaging, it is already tracks the data in the PCM data portion (53) is recorded (i.e. one of t ₁ ~t _228),
An ID is searched by a search by fast-forward. When the track is a track in which data is not recorded in the PCM data section (53) (that is, after _t229 ), an ID is searched by a search by rewind.

Then, based on the detection of the end point ID, the head scans the track _t229 next to the last still image recording track _t228 , and the new track stored in the frame memory (32) from the track _t229 to 228 tracks. One frame of video signal is recorded.

Then, in this way, the PCM data section of each track (5
When reproducing one frame of a video signal as a still image signal recorded in 3), a digital video signal reproduced from a video tape (14) by a magnetic head (13) is transmitted through an RF circuit (12). To the digital data processing circuit (25). After the digital data processing circuit (25) performs error correction and the like, the digital data processing circuit (25) supplies the data to a serial / parallel conversion circuit (34) via a changeover switch (24). Then, the reproduction data is converted into parallel data by the serial / parallel conversion circuit (34), and the parallel data is written into the frame memory (32) under the control of the memory controller (33).

At this time, the video signal for one frame is reproduced from the video tape in the same time (for example, 3.8 seconds) required for recording.

In addition, an ID signal such as a start point ID and an end point ID included in the reproduction data and subcode information such as track number data are supplied from the serial / parallel conversion circuit (34) to the memory controller (33). The controller (33) can perform various controls such as control of a reproduction track based on the subcode information.

When the video signal for one frame is written into the frame memory (32), the video signal is read from the frame memory (32) to the bit reduction circuit (31) under the control of the memory controller (33), and the bit reduction circuit In (31), the digital signal is returned to the original digital signal of the redundancy. At this time, the video signals of two fields constituting the video signal for one frame are alternately read in real time. That is, the video signal for one frame is repeatedly read in a 1/30 second cycle.
Then, the luminance signal Y and the color difference signal (R
-Y) and (BY) are supplied to the digital-to-analog converters (35), (36) and (37), respectively, and the respective digital-to-analog converters (35), (36) and (37) To convert into an analog luminance signal and a color difference signal. Then, the analog luminance signal and the color difference signal are supplied to an encoder (38) to be converted into a composite video signal, and the composite video signal is supplied from an output terminal (39) to a monitor receiver or the like. Further, the analog luminance signal and the color difference signal output from each of the digital / analog converters (35), (36) and (37) are supplied to a matrix circuit (40) and converted into primary color signals R, G and B. These primary color signals R, G, B are supplied from output terminals (41R), (41G), (41B) to a monitor receiver or the like.

By configuring the video camera of this example as described above,
A high-resolution still image converted into a digital signal is recorded. That is, when the recording mode is the still image recording mode, the digital audio signal is not recorded in the PCM data section (53) of each track, and instead, a one-frame video signal digitized at an arbitrary timing is output. Be recorded. In this case, while the continuous liquid analog video signal is being recorded in the video signal portion (56) of each track, the still image recording switch (42) is operated, and the video signal at the moment when this switch is operated is operated. Is also recorded as a digital signal. For example, as shown in FIG. 6, it is assumed that recording of a normal analog video signal, tracks T ₁ , T ₂ , T ₃ } are sequentially formed on a video tape, and the timing of recording of track T ₃ is performed. in assuming that operates the still image recording switch, of the digital video signal of the same video and analog video signals recorded on the video signal portion of the track T ₃ (56) PC
Recording in the M data section (53) is started. However, recording of the digital signal may be delayed by several tracks depending on the processing speed of the circuit. In this case, one frame recorded on the PCM data unit (53), as shown by hatching in FIG. 6 is performed until the track T ₂₃₀ over 228 tracks, any subsequent track T ₂₃₁ At this timing, the recording of the still image converted into a digital signal becomes possible again.

At this time, in this example, the last 20 tracks T _{211 to} T ₂₃₀
When recording only a still image, the first track T ₂₃₁ of the unrecorded track of the still image can be easily searched for.
By recording the next still image from ₂₃₁ , the digital video signal of the still image is continuously recorded on the track formed on the video tape, and is efficiently recorded without waste.

Since the still image recorded in this manner is a one-frame video signal converted into a digital signal, the output of the CCD imager (1) is recorded with almost no deterioration, and each image recorded in the video signal unit (56) is recorded. A still image having a higher resolution can be reproduced as compared with a case where a still image is reproduced based on a field analog video signal or a case where an analog one-field video signal is recorded as in a conventional electronic still camera. By supplying an image reproduction signal to a video printer, a hard copy of a high-resolution still image can be obtained. In this case, in this example, since the digital video signal is recorded by using the configuration for recording the PCM audio signal of the video camera according to the standard of the 8 mm video tape recorder, a slight circuit such as a frame memory is used. You can record digital video signals simply by adding
Since the configuration as a recording / reproducing apparatus can be simplified, and a sub-region of a video tape which is not originally used for recording a video signal is used as a recording medium, efficient recording without waste is performed.

In this example, since the unrecorded track can be easily searched by using the end point ID, the digital video signal of the still image can be continuously recorded without waste, and the efficiency is improved in this respect as well. With the record being made,
A new digital video signal is not mistakenly recorded on a track on which a digital video signal of a still image is already recorded, and post-erasure can be prevented. Also, at the time of reproduction, since the still images are continuously recorded in this manner, by reproducing the tape from the start end side, the recorded still images can be viewed one after another and can be efficiently reproduced. Also, since the redundancy of the digital video signal is compressed by bit reduction by the bit reduction circuit (31) and then recorded on the video tape, the data amount for one field is small, and the recording is efficiently performed in a relatively short time. Can be. Note that this bit reduction may be performed by a frame memory.

In the description noted above embodiment of G ₅ variation has been to record a digital video signal as a continuous recording simultaneously with the still image of the analog video signal as a moving video tape of the video signal portion (56) May record a dummy video signal (for example, a signal of only a synchronization signal having no video information), and may record only a digital video signal as a still image, or an 8 mm video shown in FIG. A multi-segment PCM standard of a tape recorder may be used to record only digital video signals as still images.
In this case, in addition to configuring the first to sixth segments as separate channels and recording still images individually for six channels, the first to sixth segments are used continuously for one channel. Digital video signals for frames may be recorded in a shorter time.

In the above embodiment, the last track is determined from the end point ID. However, the last track may be determined by detecting track number data recorded together with a still image digital video signal on each track. good. However, in the case of a high-speed search, the ID signal can be detected more easily.

Further, in the above-described embodiment, since the CCD imager (1) capable of outputting the imaging signals of all the pixels for one frame in one field period is used as the imaging means of the video camera, the video signal of one frame can be easily obtained. The video signal of one frame is converted into a digital signal and recorded. However, when a device capable of obtaining only one field of the image signal is used as the image capturing means, only the digital video signal of one field is converted to a still image. It may be recorded as a signal. However, in this case, the vertical resolution of the recording video signal is reduced to half that in the case of frame recording.

In the above-described embodiment, the imaging signal of the video camera is recorded as a digital video signal.
A video signal supplied from another video device such as a VTR may be recorded for one frame or one field.

Furthermore, the present invention is not limited to the above-described embodiment, and it goes without saying that various other configurations can be adopted without departing from the gist of the present invention.

H According to the present invention, a video signal as a still image is recorded simultaneously with a video signal as a moving image, and an unrecorded portion of the still image can be easily searched by a search or the like, and the still image signal is recorded on a recording medium. Recording can be performed without waste, and recording of a still image is efficiently performed with a simple configuration.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention, FIG. 2 is an explanatory diagram showing an example of an imager according to one embodiment, FIGS. 3 and 4 are explanatory diagrams showing an 8 mm video standard, FIG. FIG. 5 and FIG. 6 are explanatory diagrams each showing a recording track according to one embodiment. (1) is a CCD imager, (4) and (5) are analog / digital converters, (6) and (7) are imaging signal processing circuits, (31) is a bit reduction circuit, (32) is a frame memory, ( 33) is a memory controller, (34) is a serial / parallel conversion circuit, (35), (36) and (37) are digital / analog converters, and (42) is a still image recording switch.

Claims (1)

(57) [Claims] 1. A video signal recording apparatus which continuously records a video signal obtained continuously as a moving image and records a still image signal obtained from the video signal at an arbitrary timing. An end portion of the signal recording portion or near the end portion indicates an end portion following the still image recording.
When an ID signal is recorded and a new still image signal is recorded on a recording medium on which the still image signal has already been recorded, an end portion is detected by the ID signal, and the still image signal follows the ID signal. A video signal recording device adapted to record video.