JPH0767077A - Video recording and reproducing device - Google Patents

Abstract

PURPOSE:To save the consuming amounts of a recording medium by comparing an input video signal with a video signal from a frame memory, recording one frame of a still picture and the number of the still picture frame data at the time of judging that a picture is the still picture, and stopping the recording of the video signal of the other still picture. CONSTITUTION:A movement detecting circuit compares the video signal from an A/D converter 1 with the video signal after one frame from a frame memory(FM) 2 by a comparing part 3, and judges whether or not the picture is the still picture. When the picture is the still picture, a still picture frame number counter 14 counts the number of the frames, and a sub-code data generating part 13 integrates it into sub-code data. Next, a switch 8 switches the video signal from a shuffling circuit 7, the sub-code data, and a voice signal from a shuffling circuit 23, and supplies it to a modulator 9, and it is recorded in a tape. Thus, it is not necessary to record the same picture data of the still picture over several tracks.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video recording / reproducing apparatus capable of saving the consumption of a recording medium.

[0002]

2. Description of the Related Art FIG. 9 shows a schematic structure of a recording system in a conventional digital video recording / reproducing apparatus. The input video signal is converted into a digital signal by the A / D converter 51 and data compressed by the data compressor 52. Then, an error correction code is added by the error correction encoder 53 and segmented by the shuffling circuit 54. On the other hand, the input video signal is converted into a digital signal by the A / D converter 59, an error correction code is added by the error correction encoder 60, and the data is multiplexed by the shuffling circuit 61 after being segmented. It is multiplexed by 55 with the video signal.

A signal in which a video signal and an audio signal are multiplexed is
The signal is converted by the modulator 56 so as to match the magnetic recording characteristics, amplified by the recording amplifier 57, and then recorded on the magnetic tape driven by the tape running system 58.

By the way, in the above-mentioned conventional video recording / reproducing apparatus, the inputted video signal and audio signal, whether they are still images or moving images, are all recorded on the magnetic tape as continuous signals.

[0005]

However, as described above, when a still image is recorded on a magnetic tape as a continuous signal like a moving image, the same image data is recorded over many tracks. It wastes tape.

In view of the above circumstances, it is an object of the present invention to provide a video recording / reproducing apparatus capable of saving the recording medium consumption by avoiding recording the same image data in a still image on many tracks. To do.

[0007]

In order to solve the above-mentioned problems, a video recording / reproducing apparatus of the present invention comprises a frame memory for storing and holding an input video signal, an input video signal and the frame memory. Motion detection means for determining whether or not the image is a still image by comparing with the video signal of 1., and when it is determined to be a still image, one frame of the still image and a still image indicating how many frames the still image is continuous. Image recording control means for recording image frame number data and stopping recording of a video signal of a frame in another still image, and 1 of the number of still images based on the reproduced still image frame number data.
And a video reproduction control means for repeatedly outputting a still image for a frame.

Further, in the above structure, a memory for storing and holding an audio signal corresponding to a video signal of a still image and an audio signal stored in this memory are recorded on a recording medium when the video signal of the still image is recorded. Audio recording control means for compressing and recording data in the audio signal recording area, and data expansion of the audio signal reproduced at the time of reproducing the video signal of the still image, and the expanded audio signal while repeatedly outputting the still image. An audio reproduction control means for outputting may be provided.

Further, in the above arrangement, a memory for recording and holding an audio signal corresponding to a video signal of a still image and an audio signal stored in this memory are recorded on a recording medium after recording the video signal of the still image. Audio recording control means for recording data in the video signal recording area with or without compression, and a still image is repeatedly output without expanding or expanding the audio signal reproduced after the reproduction of the still image. An audio reproduction control means for outputting the audio signal may be provided in between.

[0010]

According to the above-described first configuration, when it is determined that the image is a still image, one frame of the still image and still image frame number data indicating how many frames the still image is continuous are recorded. Since the recording of the video signal of the frame of another still image is stopped, the same image data is not recorded over many tracks, and the tape consumption amount can be suppressed. Then, based on the reproduced still image frame number data, a still image for one frame of the still image is repeatedly output for that number of times, so that the still image is recorded as a continuous signal on a magnetic tape like a moving image and reproduced. The same image reproduction as in the case of performing is performed.

Further, according to the second structure, the audio signal corresponding to the video signal of the still image is compressed and recorded in the audio signal recording area on the recording medium when recording the video signal of the still image. Even in the above configuration in which only one frame of a still image is recorded, it is possible to record and reproduce all the audio in the still image state.

According to the third configuration, the audio signal corresponding to the video signal of the still image is data-compressed or not compressed in the video signal recording area on the recording medium after recording the video signal of the still image. As described above, all the audio in the still image state can be recorded and reproduced, as described above.

[0013]

(Embodiment 1) The present invention will be described below with reference to the drawings showing an embodiment thereof.

In this embodiment, the image data of the last one frame of the frames of the same data which is a still image is recorded on the recording tape. However, the frame of the same data is, for example, 5 in relation to the compression rate of the audio signal.
This fifth frame is set as the last one frame when the count is made. Then, as shown in FIG. 3, the audio signal corresponding to the still image is data-compressed and recorded in the audio signal recording area of each track assigned to the recording of one frame.

FIG. 1 is a block diagram of a recording system in a digital video recording / reproducing apparatus. As shown in the figure, the input video signal is converted into a digital signal by the A / D converter 1 and input to the frame memory 2 of the motion detection circuit 24.

The motion detection circuit 24 compares the video signal output from the A / D converter 1 with the video signal of one frame after output from the frame memory 2 in the comparison unit 3 to obtain a still image. Determine whether or not. Then, the determination result is output to the still image frame number counter 14 and the control pulse creation unit 15. Note that the determination as to whether or not it is a still image may be made as a still image in addition to when the image data of both frames completely match, or when the data is slightly different due to camera shake or the like. is there. In addition to the frame determination, the field determination may be performed.

The still image frame number counter 14 counts the number of still image frames based on the above judgment result, and outputs the counting result to the sub-code data generating section 13 and the memory control section 25. ing.

The subcode generator 13 incorporates the above counting result into the subcode data and outputs it to the switch 8.

The control pulse generator 15 generates control signals (1), (2) and (3) based on the above judgment result. The control signal (1) is output to the recording amplifier 11, the control signal (2) is output to the tape running system control circuit 17, and the control signal (3) is output to the memory control unit 25. The contents of the control signals (1), (2) and (3) will be described later.

The video signal read from the frame memory 2 is stored again in the frame memory 4. This is because, in the present embodiment, the last one frame of image data of the same data frame that is a still image is recorded on the recording tape.

The video signal read from the frame memory 4 is data-compressed by the data compressor 5, and an error correction code is added by the error correction encoder 6. Then, the shuffling circuit 7 divides it into segments and outputs them to the switch 8.

The switch 8 is an area switching signal creating section 16
The video signal from the shuffling circuit 7, the sub-code data from the sub-code data generation unit 13, and the audio signal to be described later from the shuffling circuit 22. It is to switch which of the audio signals is supplied to the modulator 9.

The modulator 9 is a circuit that converts the signal from the switch 8 into a signal that matches the magnetic recording characteristics.

The output from the modulator 9 is recorded on a magnetic tape driven by a tape running system 12 via a recording amplifier 11 through a recording head (neither is shown). The tape running system 12 is controlled by a tape running system control circuit 17.

Next, the voice processing system will be described. Since the video signal processing system described above is configured to be delayed by two frames, the audio signal corresponding to the video signal delayed by two frames is also supplied to the switch 8 in this audio processing system. Is configured.

In the voice processing system, the input voice signal is
The digital signal is converted by the A / D converter 18.

The switch 21 has two input terminals, and the digitized audio signal is input to one terminal. An audio signal that has been data-compressed by the data compressor 19 and has passed through the memory 20 is supplied to the other terminals. In the present embodiment, the audio signal for a still image for up to 5 frames is recorded in the audio signal recording area for 1 frame, so that the audio signal on the track in which the audio signal for 5 frames is assigned to 1 frame is recorded. The above data compression rate is set so that the data can be recorded in the signal recording area.

The switch 21 is switched on the basis of the control signal (3) from the control pulse generator 15, and if the control signal (3) is Low, it is directly connected to the A / D converter 18. While the control signal (3) is H
If it is high, it is connected to the memory 20 side.

The memory 20 is constructed so that it can store audio signals corresponding to video signals for 5 frames. When the control signal (3) becomes High, the memory control unit 25 reverses the number of still image frames input from the still image frame number counter 14 to read the audio data. Be seen.

The voice signal that has passed through the switch 21 is added with an error correction code by the error correction encoder 22, and is supplied to the switch 8 through the shuffling circuit 23.

Next, the operation of the recording system will be described.

FIG. 2 shows the input video signal and the frame memory 2.
5 is a time chart showing the relationship among the output of the motion detector, the motion determination output, the recording amplifier input signal, the control signal (1), the control signal (2), the compression completion audio data, the recording amplifier input audio signal, and the control signal (3). . In the figure, the numbers attached to the video signals indicate the field numbers, and the shaded portions indicate the fields of the still image.

The motion determination output is output by comparing the input frame image and the image delayed by one frame, and becomes High when a still image is determined. In the example shown in the figure, it is determined by comparison between the field (5, 6) and the field (3, 4) that they match, and the motion determination output becomes High. On the other hand, the field (9,1
In the comparison between 0) and the field (7, 8), it is determined that they do not match, and the motion determination output becomes Low.

When the above motion judgment output becomes High, the recording signal for the field (3), which is the start of the still image, is not yet input to the recording amplifier 11.

Then, the control pulse generator 15 which receives the High signal causes the recording amplifier 11 to stop its operation at the timing when the field (3) signal is input to the recording amplifier 11. And the control signal (1) for stopping the tape running operation to the tape running system control circuit 17.

On the other hand, when the above motion judgment output becomes Low, the recording signal for the field (7) in the last one frame of the still image is still the recording amplifier 11.
It has not been entered in.

Upon receipt of the Low signal, the control pulse creating section 15 causes the recording amplifier 11 to start its operation at the timing when the recording signal of the field (7) is input to the recording amplifier 11. For outputting the control signal (2) for the tape running system control circuit 17
On the other hand, the control signal (1) for starting the tape running operation is output. As a result, the fields (3, 4,
The recording of 5 and 6) is not performed, and the video signals of field (7) and after are recorded on the recording tape.

The control signal (1) is controlled in consideration of the delay of the mechanical starting time in the tape running system.
I try to fall a little faster than.

Next, the recording operation of the audio signal will be described.

When the motion judgment output changes from High to Low, the data compression of the audio signal corresponding to the field (3, 4, 5, 6, 7, 8) is completed. Then, the control signal (3) becomes High in synchronization with the control signal (2) becoming Low in order to start recording the video signal of the field (7, 8), and the switch 21 is switched to the memory 20 side. At the same time, a field (3, 4, 5, 6, 7, 8) is output from the memory 20 based on the still image frame numerical value.
The compressed audio data corresponding to is read out and recorded in the audio recording area of the recording tape through the switch 8 and the like.

When the control signal (3) becomes Low again, the switch 21 is switched to the A / D converter 18 side, and the audio data after the field (9) is output.

As described above, according to the above recording system configuration, when it is determined that the image is a still image, one frame of the still image and still image frame number data indicating how many frames the still image is continuous. Is recorded and the recording of the video signal of the frame in another still image is stopped, the same image data is not recorded over many tracks, and the tape consumption amount can be suppressed.

Further, since the audio signal corresponding to the video signal of the still image is data-compressed and recorded in the audio signal recording area on the recording tape when recording the video signal of the still image, only one frame of the still image is recorded. Also in the above-described configuration of recording, all the sounds in the still image state can be recorded.

Next, the reproducing system will be described.

FIG. 4 is a block diagram of a reproducing system in the digital video recording / reproducing apparatus. As shown in the figure, the signal reproduced from the recording tape of the tape running system 12 is amplified by the preamplifier 31, decoded by the decoding equalization circuit 32, and synchronously detected by the SYNC detection circuit 33. Has become. Then, the video signal taken out by the switch (not shown) is used for the deshuffling 34 and the error correction circuit 3.
5, and the frame memory 37 via the data expansion circuit 35.
It is designed to be written in. Further, the video signal read from the frame memory 37 is processed by the D / A converter 38.
Is converted into an analog signal and output.

The sub-code data separated from the reproduction signal by a separation circuit (not shown) is input to the sub-code decoder 40, decoded by this and input to the control pulse generator 41. The subcode is
As described above, the still image frame number counter information is incorporated.

The control pulse generation unit 41 generates a control signal for reproducing a still image based on the decoded subcode data, and outputs the control signal to the tape running system control circuit 17, the memory control unit 39, the switch 46, and the memory. The data is output to the control unit 49.

Based on the above control signal, the tape running system control circuit 17 stops the running of the tape by the tape running system 12 when reproducing a still image.

Further, the memory control unit 39 controls, based on the above-mentioned control signal, one frame of still image data stored in the frame memory 37 to be repeatedly read out during still image reproduction.

Further, the switch 46 is adapted to switch to the data expansion circuit 45 side when reproducing a still image based on the above control signal.

The audio signal separated by the separation circuit (not shown) is input to the deshuffling circuit 42 and the error correction circuit 43.

The switch 46 has two input terminals, and an error-corrected audio signal is input to one terminal. Then, the other terminals are supplied with a voice signal after data expansion by the data expander 45 via the memory 48. The memory 48 is controlled by the memory controller 49.

As described above, the switch 46 is switched based on the control signal from the control pulse generator 41, and during reproduction of a still image, the audio signal expanded by the data expander 45 is D / A. Input to the converter 47,
It is designed to be output as an analog voice signal.

According to the above reproducing system, the still image for one frame of the still image is repeatedly output that number of times (three times in this embodiment) based on the reproduced still image frame number data. The same image reproduction as in the case where a continuous signal is recorded and reproduced as in the case of a moving image is performed. Further, when the recorded signal for one frame is reproduced, the audio signals (audio signals for fields 3 to 8) corresponding to all still image frames are reproduced in a compressed state, and the still image for one frame is reproduced. Is repeatedly output, the audio signal is read from the memory 48 by the memory control unit 49, the data is expanded, and the audio is output.

In this embodiment, since the audio signal corresponding to the still image is recorded in the audio signal recording area of the area allocated for recording one frame, the audio signal is compressed and recorded. Further, in relation to this, further, when 5 frames of the same data are counted, for example, this 5th frame is the last 1 frame.
Although the number of frames is set to 5 as an example, it is determined in consideration of the degree of deterioration of the audio signal due to compression.

(Embodiment 2) Another embodiment of the present invention will be described below with reference to FIGS.

Explaining in comparison with the first embodiment, the digital video recording / reproducing apparatus of the present embodiment is configured to record the image data of the first one frame of the same data frame which is a still image on the recording tape. . That is, as shown in FIG. 7, fields (3, 4, 5, 5) that are still images
The first field (3, 4) among the fields 6, 7, 8) is recorded, and the fields (5, 6, 7, 8) after the field are not recorded. As shown in FIG. 6, the recording is stopped by the tape running system 1 by the control signals (1) and (2).
2 is stopped and the recording amplifier 11 is stopped. Since the image data of the first frame is recorded in this manner, the frame memory 4 shown in the first embodiment is not provided in the recording system as shown in FIG.

The audio signal corresponding to the still image is recorded in the video signal recording area on the recording tape after data recording of the one frame. That is, the field (3, 4,
Field (5, 6, 7, 8) of 5, 6, 7, 8)
The audio signal corresponding to is compressed, and the compressed audio signal is recorded when the tape running and the operation of the recording amplifier 11 are started. Therefore, it is necessary to store and hold the compressed audio signals corresponding to the above fields (5, 6, 7, 8) until the tape running and the operation of the recording amplifier 11 are started. The error correction encoder 22 holds the data. Further, since the recording signal is input to the recording amplifier 11 with a delay of one track in the one-track memory 10, the recording tape starts to move again from the stopped state so that the timing when recording the video signal of the field (9) is matched. Has become.

Further, since the compressed audio signal is recorded in the video signal recording area as described above, it is necessary to forcibly connect the switch 8 to the audio side. Therefore, the control pulse creation unit 15 outputs the control signal (4) to the area switching signal creation unit 16. When the high level of the control signal (4) is input to the area switching signal creation unit 16, the switch 8
Is forcibly switched to the audio side, and the audio signal is recorded in the image psychological recording area. In addition, immediately before the compressed audio signal is recorded in the video signal recording area, that is,
Information indicating that the image is a still image and data indicating how many frames the still image is continuous are recorded in the subcode area of the track.

The switch 21 is for selecting whether or not to compress the audio signal, and the compressed data is selected while the motion discrimination output is High. Also, DELA
The Y circuit 26 is for delaying for time adjustment with data compression.

Next, the reproducing system will be described. The structure of the reproducing system is shown in FIG. When the sub-code signal determines that the image is a still image, the recording tape is stopped from running and the writing of the video signal to the frame memory 37 is stopped. Then, the same image signal is output from the memory 37 according to the number of frames of the still image recorded in the subcode signal. During this period, the tape is short-rewinded, and when the reading of the final frame of the still image from the memory is completed by about ⅓ to ½, the field (9) is written at a timing such that the information of the field (9) is written to the memory 37. The tape running system and the memory 37 are controlled so as to reproduce the data.

On the other hand, with respect to the audio signal, even when the signal for stopping the tape running is output as described above, the tape slightly runs and during this period the tape is recorded in the video signal recording area of the track by the rotary head. The compressed audio signal will be reproduced. Then, the reproduced voice signal is data-decompressed by the data decompressor 45 and outputted as a voice.

In this embodiment, since the compressed audio signal is recorded when the video signal changes from a still image to a moving image and recording is restarted, the number of still image frames is calculated based on the still image frame count information. It is possible to compress the audio signal by setting the compression rate according to the above.

[0064]

As described above, according to the present invention, it is possible to avoid recording the same image data in a still image over many tracks, so that the tape consumption amount can be saved. .

[Brief description of drawings]

FIG. 1 is a block diagram of a recording system of a video recording / reproducing apparatus of the present invention.

FIG. 2 is a time chart showing the relationship among video signals, audio signals, and control signals of the video recording / reproducing apparatus of the present invention.

FIG. 3 is a schematic diagram showing a tape pattern on a recording tape of the video recording / reproducing apparatus of the present invention.

FIG. 4 is a block diagram of a reproducing system of the video recording / reproducing apparatus of the present invention.

FIG. 5 is a block diagram of a recording system according to another embodiment of the present invention.

FIG. 6 is a time chart showing the relationship among video signals, audio signals, and control signals according to another embodiment of the present invention.

FIG. 7 is a schematic diagram showing a tape pattern on a recording tape according to another embodiment of the present invention.

FIG. 8 is a block diagram of a reproducing system according to another embodiment of the present invention.

FIG. 9 is a block diagram showing a conventional digital video recording / reproducing apparatus.

[Explanation of symbols]

 14 still image frame number counter 15 control pulse generation unit 16 area switching signal generation unit 17 tape running system control circuit 39 memory control unit 41 control pulse generation unit 49 memory control unit

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location H04N 5/7826 5/91 H04N 5/782 C 7734-5C 5/91 R

Claims (3)

[Claims] 1. A frame memory for storing and holding an input video signal, a motion detecting means for comparing the input video signal and the video signal from the frame memory to determine whether or not the image is a still image, and a still image. When it is determined to be an image, one frame of a still image and still image frame number data indicating how many frames the still image is continuous are recorded, and recording of a video signal of a frame in another still image is stopped. A video recording / reproducing apparatus comprising: a video recording control means and a video reproduction control means for repeatedly outputting a still image of one frame of a still image by the number of times based on the reproduced still image frame number data. 2. A memory for storing and holding an audio signal corresponding to a video signal of a still image, and an audio signal stored in the memory in an audio signal recording area on a recording medium when recording a video signal of a still image. Audio recording control means for data compression and recording, and audio reproduction control for expanding the audio signal reproduced in reproducing the video signal of the still image and outputting the expanded audio signal while repeatedly outputting the still image. The video recording / reproducing apparatus according to claim 1, further comprising: 3. A memory for recording and holding an audio signal corresponding to a video signal of a still image, and an audio signal stored in the memory, a video signal recording area on a recording medium after recording the video signal of a still image. Audio recording control means for recording data with or without data compression, and the audio signal while repeatedly outputting a still image without expanding or expanding the audio signal reproduced after the reproduction of the still image. The video recording / reproducing apparatus according to claim 1, further comprising an audio reproduction control means for outputting