JPH10228751A - Information signal recording/reproducing device, recording/reproducing method and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly delete a part of a recorded area for effectively using a recording medium during recording a signal. SOLUTION: Additional information is detected from an inputted video audio signal, and the detected additional information and additional information from an input terminal 11 are supplied to a holding time decision processing circuit 13. The holding decision processing circuit 13 obtains holding time information from a reference information part 15 corresponding to the respective additional information and supplies erasable time to a recording/reproducing signal processing circuit 5. In the recording/reproducing signal processing circuit 5, the erasable time is optimally processed for recording and recorded in an additional information recording medium 8. A video audio signal is recorded in a recording medium 7. When there is no space in the recording medium 7, the erasable time is read from the additional information medium 8, an area after the passage of the erasable time is detected and the video audio signal is recorded in this area.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information signal recording / reproducing apparatus and a recording / reproducing apparatus which make effective use of a recording medium when recording main signals such as video and audio signals on the recording medium. The present invention relates to a method and a recording medium.

[0002]

2. Description of the Related Art When analog data or digital data is recorded on a recording medium such as a magnetic tape, a magnetic disk, or an optical disk, there is a case where there is no free area necessary for newly recording data on the recording medium. In that case, a new recording medium such as a blank disk may be used, but the amount of the recording medium is increased without limit.

In order to avoid this problem, it is conceivable to delete unnecessary signals from already recorded signals. For example, an automatic recording apparatus such as a monitoring video camera having a VTR uses an endless tape, and when recording is performed up to the end of the tape, it returns to the beginning of the tape and newly records an image signal. It is also conceivable to use a ring buffer instead of the endless tape and record digital data in the same manner. Furthermore, it has been proposed to record new and old information together with image data on the optical disk when recording image data on the optical disk, and to erase the oldest data when the remaining recording capacity of the optical disk becomes zero. . Furthermore, there has been proposed a method of erasing data after a certain time has elapsed from the recording time.

[0004]

However, it is not appropriate to determine whether or not the data already recorded on the recording medium is unnecessary based only on the new or old data. This is because the length of the period to be stored is affected by the content of the recorded signal. As an example,
Taking a VTR that records a television broadcast program as an example,
Among programs, programs requiring immediacy such as news and weather forecast may have a short storage period, while movie programs are required to be stored for a longer period. Also,
Some users may want to set the storage period based on broadcast channels, program titles, and the like.

Accordingly, it is an object of the present invention to provide an information signal recording / reproducing apparatus, a recording / reproducing method, and a recording medium capable of setting an appropriate storage period according to the content of a main signal to be recorded. .

[0006]

According to a first aspect of the present invention, there is provided an information signal recording / reproducing apparatus in which an arbitrary area of a recording medium is selected and recorded / reproduced. Is composed of a main signal and erasable time information associated with each recorded content of the main signal. The erasable time is stored in the reference information holding means in association with the main signal to be recorded. Means for generating information; detecting the presence or absence of a free area; if a free area exists, a main signal and erasable time information are recorded in the free area; The erasable time information is reproduced, and whether or not the recorded area is erasable is determined from the reproduced erasable time information and the current time information, and a main signal is transmitted to the recorded area determined to be erasable. Preliminary erasable time information is information signal recording and reproducing apparatus comprising a control means for performing processing for recording.

According to an eighth aspect of the present invention, in the information signal recording / reproducing method in which an arbitrary area of the recording medium is selected and recorded / reproduced, the information signal recorded on the recording medium includes a main signal and a main signal. It consists of erasable time information associated with each recorded content of the main signal, generates erasable time information using storage period information related to the main signal to be recorded, and detects the presence or absence of an empty area. If an empty area exists, the main signal and the erasable time information are recorded in the empty area, and if there is no empty area, the erasable time information of the recorded area is reproduced, and the reproduced erasable time is reproduced. Determining whether the recorded area is erasable from the information and the current time information, and recording a main signal and erasable time information in the recorded area determined to be erasable; The information signal recording and reproducing method of.

According to a ninth aspect of the present invention, there is provided a recording section for recording an information signal, wherein the information signal comprises a main signal and erasable time information associated with each recorded content of the main signal. It is a recording medium characterized by the above-mentioned.

When recording a video / audio signal, an erasable time, that is, time information indicating when the erasure can be started, can be set as information on how long the video / audio signal should be stored, and can be recorded together with the video / audio signal. The erasable time is determined based on information such as the type of the video / audio signal to be recorded.
An operation is performed according to a preset calculation formula, and the result is encoded and recorded. In addition, when performing a new recording, the recording circuit detects the recording area after the erasable time by reading and referring to the erasable time of the contents of the already recorded area, and utilizes the recording area. Make a new record.
In the case where the contents of a recorded area are stored indefinitely, the erasure time is set to be indefinite, so that the erasure of the recorded area is prohibited.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of an embodiment of a recording / reproducing apparatus to which the present invention is applied. A video / audio signal is input from an input terminal 1, and the input video / audio signal is supplied to an input signal processing circuit 2. In the input signal processing circuit 2, the supplied video / audio signal is adjusted to an optimal signal level. The adjusted video / audio signal is supplied from the input signal processing circuit 2 to the additional information detection processing circuit 3. The additional information detection processing circuit 3 detects additional information necessary for setting the erasable time superimposed on the video / audio signal, and separates the additional information from the video / audio signal. The video / audio signal is supplied from the additional information detection processing circuit 3 to the video / audio signal processing circuit 4, and the separated additional information is supplied to the storage period determination processing circuit 13.

The video / audio signal processing circuit 4 converts the video signal into a signal suitable for recording. At the time of recording, processing to separate video signal into luminance signal and chrominance signal, conversion corresponding to recording method of audio signal, band limitation by filter, analog to digital conversion, separation of synchronization signal to generate timing required for processing, Processing such as compression of the information amount of the recording signal is performed in the video / audio signal processing circuit 4.
The video and audio signals subjected to these processes are supplied to the recording / reproducing signal processing circuit 5. On the other hand, at the time of reproduction, the video / audio signal processing circuit 4 performs the reverse of these processes. A signal output during reproduction from the video / audio signal processing circuit 4 is supplied to an output signal processing circuit 9, subjected to a process such as amplification, and output as a reproduction signal.

The output signal processing circuit 9 performs signal processing such as amplification so that it can be output as a video / audio signal.
The video / audio signal on which the signal processing has been performed is output from the output terminal 10.

A signal output from the video / audio signal processing circuit 4 during recording is supplied to a recording / reproducing signal processing circuit 5. A signal output at the time of reproduction from the recording / reproduction signal processing circuit 5 is supplied to the video / audio signal processing circuit 4. The recording / reproducing signal processing circuit 5 converts the video / audio signal and information added to the video / audio signal into a signal form that can be recorded on a recording medium.

The processing of the recording / reproducing signal processing circuit 5 includes the recording / reproducing method (analog recording or digital recording, etc.) and the type of recording medium (magnetic tape, magnetic disk, optical disk,
Semiconductor memory). More specifically, FM modulation / demodulation in the case of analog recording, generation of recording units (frames, blocks, etc.) / Decomposition of recording units in digital recording, mixing / separation of additional information, generation of parity of error correction code / Error correction, processing of recording information, and the like are performed in the recording / reproducing signal processing circuit 5. In one embodiment of the present invention, the recording / reproducing signal processing circuit 5 supplies control signals necessary for these processes to the controller 14.
From the storage period determination processing circuit 1
Supplied from 3. At the time of reproduction, the erasable time at which reproduction has been performed is transmitted from the recording / reproduction signal processing circuit 5 to the controller 1.
4 is supplied.

Further, additional information is input from an input terminal 11, and the input additional information is input to an additional information signal processing circuit 12.
Supplied to This additional information is a signal by the second input means different from the video / audio signal input from the input terminal 1, and is information on the video / audio signal. The additional information signal processing circuit 12 extracts additional information necessary for setting the erasable time. The extracted additional information is supplied to the storage period determination processing circuit 13. In the storage period determination processing circuit 13, the additional information from the additional information detection processing circuit 3 and the additional information from the additional information signal processing circuit 12 are supplied to the controller 14.

In the controller 14, each additional information is supplied to the reference information holding unit 15. In the reference information holding unit 15, determination conditions, calculation formulas, and the like for determining the erasable time from each additional information are set. These determination conditions and formulas are calculated by the controller 14, and the erasable time obtained thereby is supplied to the storage time determination processing circuit 13. As described above, the storage period determination processing circuit 13 sets the erasable time of the input video / audio signal from the supplied additional information. The erasable time is supplied from the storage time determination processing circuit 13 to the recording / reproduction signal processing circuit 5.

An output signal during recording of the recording / reproducing signal processing circuit 5 is supplied to a recording / reproducing circuit 6. At the time of reproduction, a signal from the recording / reproducing circuit 6 is supplied to the recording / reproducing signal processing circuit 5.

The recording / reproducing circuit 6 performs a process for recording the signal converted by the recording / reproducing signal processing circuit 5 on the recording medium 7. The recording medium 7 is a medium that can record and reproduce video and audio signals. Additional information associated with recording and playback of video and audio signals,
That is, the additional information recording medium 8 is provided for recording and reproducing the erasable time. A part of the recording area of the recording medium 7 may be used as the additional information recording medium 8, or a separate recording medium may be used. The additional information is encoded data (digital data), and expresses characters, numerals, and symbols using a BCD code, a standardized character code (for example, an ASCII code), or the like.

The controller 14 is constituted by a microcomputer. With this controller 14,
The recording / reproducing signal processing circuit 5 and the recording / reproducing circuit 6 are controlled. The reference information holding unit 15 is associated with the controller 14.
And an operation input signal processing circuit 17. An operation input generated based on a user's operation of a key or the like is supplied to the operation input signal processing circuit 17 through the input terminal 16. In the operation input signal processing circuit 17, the signal is converted so that the conditions and the like of the reference information holding unit 15 can be set or changed based on the operation input. The converted signal is supplied to the reference information holding unit 15 through the controller 14.
As a result, the reference information holding unit 15 appropriately sets in advance the determination conditions and calculation formulas necessary for determining the erasable time for each content and genre of the video / audio signal.

Additional information is inserted as digital data in a part of the vertical blanking period of the input video / audio signal. Additional information can be inserted using a known format of a known teletext broadcast. In addition, it is possible to decode the character information inserted by the teletext decoder and to input the additional information in parallel with the video / audio signal.

The erasable time is the time when it is determined that the recorded main signal may be erased. The erasable time is calculated each time a video / audio signal to be recorded is input. In this calculation, if there is additional information from the input video / audio signal and / or additional information input by another means, these are calculated and processed in accordance with the determination conditions set in the reference information holding unit 15. It is decided by that.

An example of the determination method is as follows:
In this method, a storage period set to 5 is used. In this case, the sum of the current time (time information) at the time of recording and the storage period is set as the erasable time and recorded. The current time used at this time uses the one calculated by the controller 14, but it can also be realized by adding a processing circuit having a clock function and reading it from the circuit.

Generally, the storage period differs depending on the genre of the recorded main signal. For example, the genre of news and weather forecast needs immediateness,
The importance decreases over time. Therefore, the storage period is set to be shorter than other genres. On the other hand, it is desired that the erasable time of a movie is long. Therefore, the reference information holding unit 15 holds the information of the storage period set corresponding to the genre of the recorded content.

Further, as a method of setting the storage period of the reference information holding section 15, for example, the storage period may be set using the broadcast time zone of the recorded content as additional information. This is because the program content is uneven depending on the broadcast time zone and the importance may differ.For example, the recording area where the program of the broadcast time zone considered to be less important is recorded in another broadcast time zone Set a shorter retention period. Further, the content information as a condition for setting such a storage period can be applied in a complex manner, and the priority order and combination method of each additional information are set. For example, by combining the genre information and the broadcast time zone information described above, the setting of the storage period can be set more finely.

Furthermore, if information such as the title of a program is used, even if a continuous program that is repeatedly broadcast in a certain period is recorded, its recording area is not erased until the next program is recorded. You can set the retention period. Further, the storage period of the recording area set under another condition may be changed according to information on whether or not the program is a rebroadcast program. As described above, all the additional information corresponding to the video and audio signals can be used for setting the storage period.

The setting or change of the storage period may be performed by an external operation input. As a result, it is possible to cope with a difference in the situation, a change in the situation, and the like, and more effective settings can be made. In this case, the reference information holding unit 15 may have a plurality of pieces of storage period information, and may select the storage period information to be actually used by an operation input. Note that the reference information may be recorded on the recording medium 7 or the additional information recording medium 8, and the appropriate reference information may be read into the reference information holding unit 15 when the recording medium 7 or the additional information recording medium 8 is replaced.

The erasable time is automatically determined at the time of recording, and can be changed later by an operation input. This changes the erasable time recorded on the additional information recording medium 8 by the controller 14 based on the signal detected by the operation input signal processing circuit 17. Since the erasable time is prepared corresponding to the recording area of the recording medium 7, the erasable time corresponding to an arbitrary recording area can be changed, and the recording area corresponding to the recording content to be changed can be erased. This can be realized by rewriting the time.

Next, an example of a method of recording the erasable time on the additional information recording medium 8 will be described. The recording medium 7 for video and audio signals is divided into a plurality of recording areas. At the time of recording, recording is performed in units of recording areas, and areas corresponding to the recording areas of the video and audio signals are also secured in the additional information recording medium 8. Then, the video / audio signal is recorded in each recording area of the recording medium 7 and at the same time, the erasable time is encoded and recorded in the corresponding recording area of the additional information recording medium 8. When reproducing the video / audio signal from the recording medium 7, the erasable time is reproduced from the corresponding recording area of the additional information recording medium 8. The additional information recording medium 8 can also be realized by using a partial recording area of the recording medium 7.

When the time or capacity information for each series of recording of a program or the like can be used, the additional information recording medium 8 can be realized using the time or capacity. That is, an area for each series of recordings identified by time or capacity is provided in the additional information recording medium 8, and the additional information of the series of recordings is recorded therein. When a series of recording uses a recording area (sector or the like) which is the minimum unit of recording / reproduction on the recording medium, information (sector number or the like) of the recording area to be used is also recorded. Thereby, even when recording is performed using a plurality of recording areas, the additional information can be made common to the plurality of recording areas, and the search processing performed when selecting an erasable recording area is easy and quick. And can be.

Further, as another method, when recording a video / audio signal on the recording medium 7, the erasable time is compositely encoded with the video / audio signal and recorded for each divided recording area of the recording medium. You may do it. For example, when recording a video / audio signal as a digital signal, an erasable time can be recorded as an ID signal, sub data, or the like in the format of the recording data.

Next, the use of the erasable time will be described. If there is no empty area where nothing is recorded on the recording medium 7 when recording the video / audio signal, the content of the already recorded recording area is erased and new recording is performed in that area. . At this time, the erasable time information is used to determine which recording area is to be erased. Here, all the recording areas recorded on the recording medium 7 have erasable time information set at the time of recording or after that.

An example of a process for recording a video / audio signal using the erasable time is shown in the flowchart of FIG.
This flowchart is started from step S1. In step S1, the current time at which the video / audio signal is recorded is obtained. In step S2, the content of the video / audio signal to be recorded is obtained, and a classification is selected according to the content.
In step S3, the storage period of the video / audio signal is determined based on the information in the reference information holding unit 15. Step S4
In, the erasable time is determined according to the determined storage period.

When a video / audio signal to be recorded is input,
First, the controller 14 checks whether or not the recording medium 7 has a free area. (Step S5) The free area is
An area in which nothing is recorded, including an area in which recorded contents have been erased in advance by an operation input.

As a method for detecting the free area, the erasable time of the additional signal recording medium 8 is prepared corresponding to the recording area, so that a signal indicating that the area is a free area is recorded instead of the erasable time. In this case, it can be determined whether or not each recording area is a free area only by reading out this signal. This is possible because the erasable time is not required for the empty area. In addition, by setting a past time to the erasable time corresponding to a free area, the area can be made a free area, and therefore, such a method can also be realized.
Of course, a dedicated recording area may be prepared separately from the erasable time.

In step S5, if it is determined that there is a free area, control is transferred to step S6, and if it is determined that there is no free area, control is transferred to step S9. In step S6, the free area of the recording medium is set as the recording area of the video / audio signal. In step S7, recording of the video / audio signal is started, and at the same time, the erasable time of the video / audio signal is also recorded. In step S8, it is determined whether or not there is a video and audio signal to be recorded. If it is determined that there is still a video and audio signal to be recorded, the control proceeds to step S5. As described above, in step S5, even when there is a video / audio signal to be further recorded, as long as there is a free area, recording is performed using this free area. If it is determined in step S8 that all of the video and audio signals to be recorded have been recorded, this flowchart ends.

In step S9, since there is no free area for recording the video and audio signals on the recording medium, a search is performed for each recorded area. Then, in step S10, the erasable time is read for each recorded area on the recording medium. That is, in steps S9 and S10, if there is no free space or if there is a shortage, the controller 14
Controls the recording / reproducing circuit 6 to store the erasable time corresponding to each recording area on the recording medium 7 in the additional information recording medium 8.
, And decodes the erasable time encoded by the recording / reproducing signal processing circuit 5.

In step S11, it is determined whether or not the recorded area can be erased by comparing the read erasable time with the current time.
If it is determined in step S11 that the recorded area can be erased, the control shifts to step S7, and if it is determined that the area cannot be erased, the control shifts to step S9. That is, the control of steps S9, S10, S11 is repeated until a recording area for recording the video / audio signal is found.

That is, the controller 14 compares the erasable time read from the additional information recording medium 8 with the current time, determines whether the erasable time has passed the current time, and erases the corresponding recording area. It is determined whether or not to do. If the erasable time has passed, since the content recorded in the corresponding recording area is erasable, this area is set as a new recording area (empty area), and the operation proceeds to the recording processing operation. At this time, the erasable time determined based on the additional information of the new recording is encoded and recorded in the corresponding area of the additional information recording medium 8.

As a method of selecting a recording area for this new recording, reading of the erasable time is performed for all the recording areas, and the erasable time is read from the erasable time in the recording area after the erasable time. It is also possible to select a recording area with a large elapsed time. Further, it is also possible to realize that the detection of the empty area and the detection of the recording area whose erasable time has passed have been performed in advance at the time of the recording, and the information is stored in another area. In this case, the erasable time is updated each time it is rewritten.

To set an erasure prohibition area for an already recorded area, it is possible to set an erasable time indefinitely. To set an empty area, set the erasable time to a past time. It becomes possible by doing.

[0041]

According to the present invention, when a video signal and an audio signal are recorded, if there is no free area, the recording area is determined by referring to the erasable time and recording is performed. Erasing insignificant recorded contents enables effective use of the recording capacity of the recording medium. In addition, even if the recording content has passed the erasable time, the recording capacity is saved until the capacity of the free area becomes insufficient for new recording, so that the recording capacity can be used effectively.

[Brief description of the drawings]

FIG. 1 is a block diagram of one embodiment of the present invention.

FIG. 2 is a flowchart used for describing the present invention.

[Explanation of symbols]

2 ... input signal processing circuit, 3 ... additional information detection processing circuit, 4 ... video / audio signal processing circuit, 5 ... recording / reproduction signal processing circuit, 6 ... recording / reproduction circuit, 7 ... · Recording medium, 8 ... additional information recording medium, 9 ... output signal processing circuit, 12 ... additional information signal processing circuit, 13 ...
Storage period determination processing circuit, 14 ... controller, 15
... Reference information holding unit, 17 ... Operation input signal processing circuit

Claims (9)

[Claims] 1. An information signal recording / reproducing apparatus in which an arbitrary area of a recording medium is selected and recorded / reproduced, wherein an information signal recorded on the recording medium is a main signal and a main signal. Means for generating erasable time information using the storage period information of the reference information holding means in association with the main signal to be recorded, comprising erasable time information associated with the recorded contents; The presence / absence is detected, and if the free area exists, the main signal and the erasable time information are recorded in the free area. If the free area does not exist, the erasable time information of the already recorded area is recorded. Then, it is determined from the reproduced erasable time information and the current time information whether or not the recorded area is erasable. The main area is determined for the recorded area determined to be erasable. Signal and the information signal recording and reproducing apparatus comprising a control means for performing a process for recording the erasable time information. 2. The information signal recording / reproducing apparatus according to claim 1, wherein said reference information holding means includes additional information detected from said main signal and / or additional information corresponding to said main signal supplied from outside. An information signal recording / reproducing apparatus characterized in that the storage period information is output from the apparatus. 3. An information signal recording / reproducing apparatus according to claim 1, wherein said main signal and said erasable time information are recorded on a common recording medium. 4. The information signal recording / reproducing apparatus according to claim 1, wherein said main signal and said erasable time information are recorded on separate recording media. 5. The information signal recording / reproducing apparatus according to claim 1, wherein said reference information holding means is capable of selecting or changing a condition setting based on an external input. apparatus. 6. The information signal recording / reproducing apparatus according to claim 1, wherein erasure prohibition is set by making the storage period information indefinite. 7. The information signal recording / reproducing apparatus according to claim 1, wherein an empty area is set by setting the storage period information to a past time. 8. An information signal recording / reproducing method in which an arbitrary area of a recording medium is selected and recorded / reproduced, wherein the information signal recorded on the recording medium is a main signal and a main signal. The erasable time information is composed of erasable time information associated with the recorded contents, the erasable time information is generated by using the storage period information related to the main signal to be recorded, and the presence or absence of a free area is detected. If there is, the main signal and the erasable time information are recorded in the vacant area. If the vacant area does not exist, the erasable time information of the recorded area is reproduced. From the erasable time information and the current time information, it is determined whether or not the recorded area is erasable. The main signal and the erasable information are recorded for the recorded area determined to be erasable. Information signal recording and reproducing method characterized by recording the time information. 9. A recording unit for recording an information signal, wherein the information signal comprises a main signal and erasable time information associated with each recorded content of the main signal. recoding media.