JP2630409B2 - Image recording and playback device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a digital video tape recorder (hereinafter referred to as "digital VT") for inputting and recording and reproducing digital image data or image data obtained by digitizing a video signal.
R "), which can record moving images and still images in the same recording medium, and distinguishes moving images and still images during playback, and stores data corresponding to each image. The present invention relates to an image recording / reproducing apparatus capable of reproducing each image by performing processing.

[Conventional technology]

In recent years, with the advance of digital technology, among image recording / reproducing apparatuses, development of a digital VTR for digitizing a video signal of a television and recording / reproducing on a magnetic tape with high image quality has been advanced. And such digital VT
R1 is, as shown in FIG. 6, an A / D converter 2 for digitizing a video signal input from another image device or the like, and this A / D converter 2.
A coding circuit 3 for inputting digital image data from the / D converter 2 and adding an error correction code for correcting a code error at the time of recording at the time of reproduction, and an error correction code added by the coding circuit 3 A recording / reproducing unit 4 for inputting digital data and recording / reproducing the data on / from a recording medium such as a magnetic tape; and a decoding circuit 5 for correcting a code error of the digital data read from the recording / reproducing unit 4 by the error correction code and outputting the same. And a D / A converter 6 for converting the digital data corrected in code error by the decoding circuit 5 into a video signal and outputting the video signal. Such digital VTR1 is
Since the standard television signal is digitally recorded in real time, the recording rate is as high as 80 to 100 Mbit / sec, and high-density recording is performed. Therefore, the encoding circuit 3 is used to correct a bit error caused by dropout of a magnetic tape or the like. And a decoding circuit 5. However, since the recording density is high, the error rate is 10
^-8 it is about (can not be corrected 1 ratio of bit Ide errors 10 ⁸ bits). At this time, in the case of a moving image in which the image content appears to move, it is considered that there is no visual problem if the error rate is 10 ⁻⁸ or less.

On the other hand, it has been considered to record a still image in which the image content appears to be stationary by utilizing the large capacity of the digital VTR 1. In this case, the data content of each still image is completely different from that of a still image, unlike a moving image. Therefore, if the error rate is 10 ⁻⁸ , the reliability is low. In this regard, in the case of a still image recording device using an optical disk or a magnetic disk as a recording medium, the error rate is 10 ^-12 or less, and the reliability is improved by four digits as compared with the digital VTR 1, and the problem is that Absent.

Therefore, in order to record a still image using a digital VTR, conventionally, as shown in FIG. 7, an image memory 7 is provided between the A / D converter 2 and the encoding circuit 3 and a decoding circuit 5 is provided. A majority decision circuit 8 is provided between the A / D converter 6 and the digital image data output from the A / D converter 2. The digital image data is temporarily stored in an image memory 7, and the same image data is stored in the image memory 7. For example, three consecutive readings are performed, and the same still image is recorded on a recording medium through the recording / reproducing unit 4, for example, three times. At the time of reproducing, the three recorded same still images are read out. Of the same bit for the same still image. As a result, the error rate was improved to about 10 ^-15 .

[Problems to be solved by the invention]

In such a conventional image recording / reproducing apparatus, the sixth
A digital VTR 1 for moving images as shown in the figure and a digital VTR 1 'for still images as shown in FIG. 7 are required, and moving images and still images are separated on separate magnetic tapes or the like using the respective devices. I was recording. Therefore, dedicated devices are required for moving images and still images, respectively, requiring space and increasing costs, and it is impossible to record moving images and still images together on the same magnetic tape. At the time of reproduction, the digital VTR 1 for moving images and the digital VTR 1 'for still images must be used separately, and the magnetic tape on which moving images are recorded and the magnetic tape on which still images are recorded are distinguished from each other. Had to be loaded, which made the operation complicated.
Furthermore, even if a moving image and a still image are recorded on the same magnetic tape, it is difficult to distinguish between the moving image and the still image because of the different data processing during reproduction.

Therefore, an object of the present invention is to provide an image recording / reproducing apparatus which can solve such a problem.

[Means for solving the problem]

Means for solving the above-mentioned problems are as follows: a coding circuit for inputting digital image data or image data obtained by digitizing a video signal and adding an error correction code for correcting a code error at the time of recording at the time of reproduction; A recording / reproducing unit for inputting digital data to which an error correction code has been added by the encoding circuit and recording and reproducing the data on and from a recording medium; and correcting the code error of the digital data read from the recording / reproduction unit by the error correction code. An image recording / reproducing apparatus having a decoding circuit for outputting the digital image data between the input section of the digital image data and the encoding circuit, and storing the input digital image data as a moving image or a still image. The image data is output only once in the case of a moving image, and the same image data is output multiple times in the case of a still image according to the discrimination information indicating whether there is any And an identification memory for recording the discrimination information in a part of an image or a blanking portion or a sound or a control track, and a digital signal from the decoding circuit is provided between the decoding circuit and the output portion of digital image data. A majority circuit is provided for inputting data and deciding the same image data recorded a plurality of times during still image recording, and discriminating information read from a recording medium is inputted to determine whether reproduced image data is a moving image or a still image. This is performed by an image recording / reproducing apparatus provided with a control circuit for controlling the execution or non-execution of majority by the majority circuit.

(Operation)

When recording image data on a recording medium, the image recording / reproducing apparatus configured as described above temporarily stores input digital image data in an image memory and checks whether the image data is a moving image or a still image. In the case of a moving image, the image data is output only once, and in the case of a still image, the same image data is output multiple times. Thus, the image data of the moving image and the still image are mixedly recorded on the recording medium of the recording / reproducing unit, and in the case of a moving image, the discrimination information corresponding to the moving image is recorded on a part of the recording medium. In the case of, discrimination information corresponding to the still image is recorded. When reproducing the moving image and still image data which are mixedly recorded on the same recording medium in this way, the discrimination information is read together with the image data from the recording medium, and the decoding circuit corrects the code error. I do. Then, the control circuit determines whether the read image data is a moving image or a still image based on the input determination information. next,
Under the control of the control circuit, when the image data is a moving image, the majority circuit outputs the data as it is without executing a majority decision on the data, and executes a majority decision on the same image data recorded a plurality of times when the image data is a still image. Output. Thereby, the moving image and the still image recorded mixedly on the same recording medium are discriminated and reproduced.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram showing an embodiment of an image recording / reproducing apparatus according to the present invention. This image recording / reproducing apparatus 10 is for inputting and recording / reproducing digital image data or image data obtained by digitizing a video signal from an image apparatus or the like (not shown), and is, for example, a digital VTR, as shown in FIG. As described above, it has the A / D converter 2, the encoding circuit 3, the recording / reproducing unit 4, the decoding circuit 5, and the D / A converter 6.

The A / D converter 2, and outputs the image data by digitizing the video signals V ₁ to be input from the unillustrated television system or the like. The encoding circuit 3 includes the A / D converter 2
It is intended for adding an error correction code for correcting code errors in recording the time of reproduction to the digital image data D ₁ of the input from the digital data or not shown digital system output from. The recording / reproducing unit 4 inputs the digital data to which the error correction code has been added by the encoding circuit 3 and records and reproduces the data on a recording medium such as a magnetic tape. The decoding circuit 5 corrects a code error of the digital data read from the recording / reproducing unit 4 by the error correction code added by the coding circuit 3. Further, D / A converter 6 is intended to be sent to an unillustrated television system or the like and converts the digital data corrected the code error in the decoder circuit 5 to the video signal V _2.
Note that digital data correcting code error in the decoding circuit 5 without passing through the D / A converter 6, may be sent directly to an unillustrated digital system as the image data D ₂ of the digital.

Here, in the present invention, an image memory 7 is provided between the A / D converter 2 and the encoding circuit 3 and a selection circuit 11 is provided, and the decoding circuit 5 and the D / A converter 6 Between them, a distribution circuit 12 is provided, a majority decision circuit 8 is provided, and a control circuit 13 is provided.

The image memory 7 stores the digital image data D ₁ of the input from the digital image data or not shown digital system of the A / D converter 2, it is transferred from a digital system outside illustrated, and the input Discrimination information indicating whether the image data is a moving image or a still image
The D _3, in the case of video in the case of a still image is output once the same image data and outputs the same image data a plurality of times, for example three times. Note that the image data identification information D ₃ in the case of still image, also has order information of the image in a plurality of times the output.

Selection circuit 11 is for selecting and outputting one of the image data and the discrimination information D ₃ output from the image memory 7 to the code circuit 3, as shown in FIG. 2, the selector 14 And a controller 15. Selector 14 is used to input the identification information D ₃ from the digital system of the image data and not shown from the image memory 7, and selects and outputs either. Further, the controller 15, the selector 14 is for switching the selector 14 to select either the image data or discrimination information D _3.
Next, the operation of the selection circuit 11 will be described with reference to FIG. 3 showing a data area on a magnetic tape 16 as a recording medium. First, the controller 15 determines the discrimination information area which is a part of the video track 17 on the magnetic tape 16.
18 switches the selector 14 so that identification information D ₃ is recorded, and outputs the determination information D ₃ to the code circuit 3. And meantime, the image data may be held in the image memory 7, the ends were recorded in the determination information D ₃ discrimination information area 18, the controller 15 switches the selector 14 to the image data side. Next, the image data held in the image memory 7 is output to the encoding circuit 3.

Distribution circuit 12 is for distributing the digital data output from the read decoding circuit 5 from the recording medium of the recording and reproducing unit 4 to the image data D ₄ and discrimination information D _3, as shown in Figure 4, the distribution It comprises a vessel 19 and a controller 20. The distributor 19 includes, among the digital data whose code errors have been corrected by the decoding circuit 5, image data D ₄ to be transferred to a majority circuit 8 described later and discrimination information D ₃ to be transferred to a control circuit 13 described later.
And is distributed to. The controller 20, when the image data D ₄ outputs the data to the majority circuit 8, when the discrimination information D ₃ is intended to switch the distributor 19 to output the data to the control circuit 13.

The majority circuit 8 is for a majority of the same image data a plurality of times recorded in the still image recorded on a recording medium of the image data D ₄ enter the recording and reproducing unit 4 from the distribution circuit 12, in this embodiment the three It is assumed that a majority of the images are decided, and as shown in FIG. 5, it is composed of a first image memory 21, a second image memory 22, and a majority decision unit 23. First image memory 21
Is for storing the first image data d ₁ of the three pieces of image data output from the distribution circuit 12. Second image memory 22 is for storing the second image data d ₂ of the three pieces of image data output from the distribution circuit 12. The third image data d ₃ from the distribution circuit 12
Is directly input to the majority decision unit 23 described later. Then, the third image data d ₃ of the input at the same time, so reading the first and second, respectively from the image memory 21, 22 of the first image data d ₁ and the second image data d ₂ I have. Also, majority portion 23, the first and second and third image data d ₁ of, d _2, d ₃ and enter the image data d ₁ to d ₃ of the three
The majority of the data of the same bit is determined at the same address, and the result is output to the D / A converter 6 shown in FIG. 1 or a digital system (not shown). On the other hand, at the time of moving image recording, the same image data is output only once to the recording medium of the recording / reproducing unit 4 and only one image is recorded. Therefore, the image data d ₄ output from the distribution circuit 12 at the time of reproduction is The data is not directly taken into the second image memories 21 and 22, but is directly transferred to the majority decision unit 23 to pass through and output without executing the majority decision.

Further, the control circuit 13 inputs the determination information D ₃ output from the distribution circuit 12, execution of the majority of the image data D ₄ that is reproduced to determine whether the moving image or a still image the majority circuit 8 , Non-execution. Then, when it is determined that the still image, the order information of the image that combines the above determination information D _3, namely of whether image data read out from the recording and reproducing unit 4 strikes the ordinal number of the three pieces of image data information by, controls the first and second image memories 21 and 22 of the majority circuit 8, three sheets majority circuit to run where the image data are aligned with three majority decision of the image data d ₁ to d ₃ of 8 is controlled. Further, when it is determined that the moving image, the first and second image memories 21 and 22 of the majority circuit 8 is not taken into the image data, the image data d ₄ from the distribution circuit 12 are majority decision unit
At 23, control is made so as to pass without executing a majority decision. By such a control circuit 13, execution of majority by the majority circuit 8 in accordance with a moving image or a still image,
Non-execution can be controlled.

Next, the operation of the thus configured image recording / reproducing apparatus will be described. First, in FIG. 1, in order to record image data on a recording medium such as a magnetic tape of the recording / reproducing unit 4, a video signal input from a television system or the like (not shown) is used.
Image data obtained by digitizing V ₁ by the A / D converter 2 or digital image data D ₁ input from a digital system (not shown) is temporarily stored in the image memory 7. At this time, from a digital system (not shown), discrimination information D ₃ indicating whether the input image data is a moving image or a still image.
Is transferred. Then, this identification information D _3, when image data the input of video outputs only once the same image data from the image memory 7, the selecting circuit 11
In while selecting switching between the image data and the discrimination information D _3, as shown in FIG. 3, corresponds to the image data of the moving image data and its video in a predetermined area of the video track 17 on the magnetic tape 16 a discrimination information D ₃ to be recorded. When the input image data is a still image, the same image data is output from the image memory 7 three times, for example.
Via a selection circuit 11, as shown in FIG.
In a predetermined area of the video track 17 on 16 and three sheets of image data of a still image discrimination information D ₃ corresponding to the still picture in each of the three pieces of image data are recorded. Thus, moving images and still images can be mixedly recorded on the same magnetic tape 16.

Next, in order to reproduce a mixture of moving images and still images recorded on the same recording medium (magnetic tape 16) of the recording / reproducing unit 4 as described above, the discrimination information is sent together with the image data from the recording medium. read, correct the decoding error in the decoding circuit 5, to distribute the digital data from the decoding circuit 5 to the image data D ₄ and identification information D ₃ in distribution circuit 12. Then, enter the determination information D ₃ to the control circuit 13, the image data which the control circuit 13 is inputted from the distribution circuit 12 to the majority decision circuit 8
If D ₄ is determined to be a still image, controls to the majority in the majority circuit 8. That is, the majority decision circuit 8
Is the order information of the image that combines the above determination information D _3, as shown in FIG. 5, the first and second of the three sheets image data d ₁ to d ₃ of which is sequentially input from the distribution circuit 12 of Image data d ₁ and d ₂ are stored in first and second image memories 21 and 22, respectively.
Fetches, the above three image data d ₁ in a third majority portion 23 reads out simultaneously with the input of the image data d ₃
Respectively majority of data of the same bit in the same address to d _3. The result is output as a still image video signal V ₂ to a television system or the like (not shown) via a D / A converter 6 shown in FIG. 1 or as digital image data D ₂ of a still image to a digital system (not shown). I do. The image data D ₄ input to the voting circuit 8 when determined that a moving image is controlled so as not to perform the majority vote in the majority circuit 8. That is, as shown in FIG. 5, the majority decision circuit 8 outputs one image data d inputted from the distribution circuit 12.
₄ is not taken into the first and second image memories 21 and 22,
The data is directly transferred to the majority decision unit 23 and output as it is without executing the majority decision. D / A converter video to unillustrated television system or the like via the 6 video signal V ₂ indicative of the output signal in Figure 1
As also output to an unillustrated digital system as a digital image data D ₂ of the video. Thus, it is possible to discriminate between a moving image and a still image recorded mixedly on the same recording medium, perform data processing on each of them, and reproduce each image.

In the third diagram, the discrimination information D ₃ for discriminating between moving and still images, video track on the magnetic tape 16
Although the recording is performed in the discrimination information area 18 set as a part of the image in the image 17, the present invention is not limited to this, and the recording may be performed in a sound other than the video track 17, a control track or a blanking unit. Is also good. In this case, the selection circuit 11 and the distribution circuit 12 shown in FIG. 1 may be omitted.

〔The invention's effect〕

Since the present invention is configured as described above, the recording / reproducing unit 4
By recording the discrimination information D ₃ indicating which moving image or a still image together with the image data on a recording medium, moving image and with a still image can be recorded mixedly on the same recording medium, the moving image in reproduction still Each image can be reproduced by discriminating the image and performing data processing corresponding to each image data. Therefore, only one device can be used for both moving images and still images, which can save space and cost. Also, at the time of recording and reproduction, it is not necessary to separately load a recording medium for a moving image or a still image in a dedicated device as in the related art, and the same recording is performed for one device. It is only necessary to load a medium, handling is simplified, and operability can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of an image recording / reproducing apparatus according to the present invention, FIG. 2 is a block diagram showing an internal configuration of a selection circuit, and FIG. 3 is a description showing a data area on a magnetic tape as a recording medium. FIG. 4, FIG. 4 is a block diagram showing the internal configuration of the distribution circuit, FIG. 5 is a block diagram showing the internal configuration of the majority circuit, FIG. 6 is a block diagram showing a conventional digital VTR for moving images, and FIG. Conventional digital VTR for still images
FIG. 2 A / D converter, 3 Code circuit, 4 Recording / reproducing unit, 5 Decoding circuit, 6 D / A converter, 7 Image memory, 8 Majority decision circuit, 10 ...... Image recording / reproducing device, 11
…… Selection circuit, 12… Distribution circuit, 13 …… Control circuit, 16…
… Magnetic tape, D ₃ …… Discrimination information.

Claims (2)

(57) [Claims] An encoding circuit for inputting digital image data or image data obtained by digitizing a video signal and adding an error correction code for correcting a code error at the time of recording at the time of reproduction, and an error correction circuit using the code circuit. A recording / reproducing unit that inputs digital data to which a code is added and records and reproduces the data on a recording medium, and a decoding circuit that corrects a code error of the digital data read from the recording / reproducing unit by the error correction code and outputs the result. In the image recording / reproducing apparatus having the digital image data, the input digital image data is stored between the input section of the digital image data and the encoding circuit, and the moving image is determined based on discrimination information indicating whether the image data is a moving image or a still image. In the case of, there is provided an image memory for outputting the image data only once, and for a still image, outputting the same image data a plurality of times. In both cases, the discrimination information is recorded in a part of an image or in a blanking portion or a sound or a control track, and digital data from the decoding circuit is input between the decoding circuit and a digital image data output portion to output a still image. A majority circuit is provided to determine the majority of the same image data recorded a plurality of times during recording, and discriminating information read from the recording medium is input to determine whether the reproduced image data is a moving image or a still image. An image recording / reproducing apparatus provided with a control circuit for controlling the execution and non-execution of the operation. 2. The image processing apparatus according to claim 1, wherein when the discrimination information is recorded as part of an image, image data output from the image memory and the discrimination information are selected between the image memory and the coding circuit. And a distributing circuit for distributing digital data from the decoding circuit to image data and discrimination information is provided between the decoding circuit and the majority decision circuit. 2. The image recording / reproducing apparatus according to claim 1.