JP3364986B2 - Attached information detection device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is, for example, a so-called 8 mm.
The present invention relates to an attached information detecting device suitable for use in a reproducing system such as a video tape recorder device or an 8 mm video camera device.

[0002]

2. Description of the Related Art Today, a so-called 8 m recording medium is used because it is small and lightweight and does not occupy a storage area.
m videotapes have become widely used.

On this 8 mm video tape, a recording signal (video signal and audio signal) of one field is obliquely recorded on one track by a so-called rotary head as shown in FIG. 7, for example.

In FIG. 7, the track on which the recording signal of one field is recorded has a predetermined pulse modulation (P
CM: PULSE CODE MODULATION) A PCM audio signal recording area for recording an audio signal, a video recording area for recording a video signal, and a PCM audio signal recording area formed between the PCM audio signal recording area and the video recording area. And an attached information recording area.

As shown in FIG. 8A, the attached information recording area is 3H (H is about 64 μse in one horizontal scanning line period).
c. ) PCM postamble and 3.8H video guard (VP guard), which is used for recording various additional information as described below.

First, so-called auxiliary information for indexing (hereinafter referred to as 0 index) is recorded in the auxiliary information recording area. This 0 index is the above PC
It is designed to be recorded in the PCM postamble attached to the M audio signal, and as shown in FIG. 8A, the latter half 1 of the PCM postamble in which all "1" data has been recorded until then. It is recorded by rewriting the portion of .5H to "0" as shown in FIG.

The 0 index is recorded by rewriting the PCM postamble for, for example, about 10 seconds, and it is possible to find a desired image or the like even during a high speed search.

However, the above-mentioned 0 index can only be used for a mere cueing function because only "0" and "1" data is recorded. Therefore, the instrument coding index was developed to record the time code indicating the absolute elapsed time on the tape corresponding to the video together with the auxiliary information for cueing.

The instrument coding index is attached to the PCM audio signal as shown in FIG. 9 and recorded in the latter half 1.5H of the PCM postamble. It is composed of a total of 6 data blocks including blocks 0 to 5 in which data is recorded, and an end block in which an end mark indicating the end of recording of the data is recorded.

The above-mentioned one block includes a 3-bit synchronizing signal, a total of 5 words of 8-bit word 0 to word 4, and 8-bit error correction code (CRCC: Cycl).
ic Redundancy Check Code).

The synchronization signal recorded at the beginning of each word is 1.5T + 1.5 with 1-bit period T (for example, 1 / T = 2.9 MHz) as shown in FIG.
The signal has T as one cycle, and the 8 mm video tape recorder, for example, reproduces the data of each word by using the synchronization signal as a trigger. In addition, the above end mark is 1.5T + 1.5T 1
More than 12 sets of signals (1.5T of 24 sets in total) are recorded.

By recording this instrument coding index, it is possible to perform the above-mentioned cueing, and it is possible to display the absolute elapsed time and the like on the tape corresponding to the video together with the video.

However, since both the 0 index and the instrument coding index are recorded by being attached to the PCM audio signal, only a model capable of PCM recording the audio signal can support it.

Therefore, a video marker has been developed as a cueing system which can be realized even if the model is not compatible with the PCM voice.

The video marker is recorded over approximately 1.5H, for example, in a substantially intermediate portion between the PCM audio signal recording area and the video recording area, as shown by hatching in FIG. This video marker has a search mark recorded for cueing, and 0.24H after the search mark.
It is composed of one block of data such as a time code recorded over the entire length. The above search mark is
When there is an index, "0" is recorded over 1.26H, and when there is no index, "1" is recorded over 1.26H.

The 1-block data of the video marker is recorded with a 3-bit synchronizing signal, a total of 5 words of 8-bit words 0 to 4, an 8-bit error correction code, and an end mark. It consists of an end block.

Since the video marker is recorded independently of the PCM audio signal and the video signal, the video marker can be detected and reproduced even if the model does not support the PCM audio, and the cue can be performed. The absolute elapsed time on the tape corresponding to the video can be displayed together with the video.

Here, since it can be said that the attached information such as the data code is useful information only when many 8 mm video devices can be recorded / reproduced in the same manner, the common format is supported by the makers of the 8 mm video devices. 5 block video subcodes and 1 block video subcodes have been developed.

The above 5-block video subcode is shown in FIG.
The erase code is recorded in the auxiliary information recording area as indicated by the diagonal lines in 2, and the data of "1" is recorded from a position spaced 0.1H from the PCM audio signal recording area, and a head over 1.0H. It consists of a search mark recorded for output and data recorded over 0.8H. The search mark is recorded with "0" when there is an index, and is recorded with "1" when there is no index.

The above data is divided into 5 blocks, each of which is a 51-bit block 0 to a block 4, and is recorded. In the latter part of the block 4, 1.5T + 1.5.
An end mark composed of a total of 12 sets of signals with T as one set is recorded.

The above-mentioned one block is composed of a 3-bit synchronizing signal, a total of five words of word 0 to word 4 of 8 bits, and an error correction code of 8 bits.

Next, the 1-block video subcode is recorded over the 2.24H in the auxiliary information recording area as shown by the hatching in FIG. The 1-block video sub-code is composed of an erase code in which "1" data is recorded for 1.0H, a search mark recorded for 1.0H, and 1 block of data recorded for 0.8H. ing. The search mark is recorded with "0" when there is an index, and is recorded with "1" when there is no index.

Data corresponding to the block 4 of the 5-block video subcode is recorded as the data, and a 3-bit synchronization signal and 8-bit words 0 to 4 are used for a total of five data. It consists of a word, an 8-bit error correction code, and an end mark.

Since the 5-block video subcode has a wide data recording area, it is possible to record various additional information such as channel information when recording a television broadcast and photographing information when photographing with a camera. can do.

[0025]

However, as described above, the attached information includes 0 index, instrument coding index, video marker, 5 block video subcode, 1 block video subcode, and the like.
In addition to different recording positions, the length of the search mark (the length of "0" that is continuously recorded) and the number of data blocks also differ.

Therefore, the conventional accessory information detecting device for detecting the accessory information cannot accurately detect all of the plurality of accessory information.

Specifically, the above-mentioned conventional auxiliary information detecting device starts reading data when a synchronizing signal is detected, and once starting reading data, does not accept the synchronizing signal for 0.24H. ing.

Therefore, as shown in FIG.
When the video marker or 1-block video subcode having a data block of 14H and an end block of 0.10H is recorded, the data of the data block is recorded because the end block exists between 0.24H. When it is readable and the above-mentioned 5 block video subcode shown in FIG. 7B is recorded, the end block exists between 0.24H and the data in the block 5 can be read. However, when the instrument coding index shown in FIG. 7C is recorded, the data of any block could not be read because the end block does not exist between 0.24H. .

Further, for example, the instrument coding index is recorded in the latter half of the PCM postamble, but the video marker is recorded after the instrument coding index so as not to erode the PCM audio signal. It

For this reason, in the conventional attached information detecting device for detecting the attached information, even if a video marker is newly recorded on the tape on which the instrument coding index is recorded, it is recorded before the above. Instrumental
Since the coding index is detected first, only the instrument coding index can be read.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an attached information detecting apparatus capable of accurately detecting all attached information existing in plural.

[0032]

An accessory information detecting apparatus according to the present invention is an accessory information detecting apparatus for detecting accessory information recorded together with record information on a recording medium, wherein the accessory information is recorded at the head portion of the accessory information. Signal detecting means for detecting the synchronized signal being detected, and additional information recorded after the synchronizing signal until re-triggered by the detection output from the synchronizing signal detecting means until the next detection output is supplied. Additional information reproducing means for reproducing the data, window pulse forming means for forming a window pulse for detecting an end mark indicating the recording end position of the additional information based on the detection output from the synchronizing signal detecting means, and the window. End mark detection for outputting end mark detection output when the above end mark is detected in the window pulse from the pulse forming means Stage, and when the end mark detection output is supplied from the end mark detecting means, an accessory for controlling the accessory information reproducing means to stop the accessory information reproducing operation until the synchronization signal is detected next time. The above problem is solved by having an information reproduction control means.

The accessory information detecting device according to the present invention is
The first 0 data for detecting the length of 0 data continuously recorded in the first half of the attached information and outputting the attached information when the length of the 0 data is a predetermined length. When detecting means and a window pulse for detecting an end mark indicating the recording end position of the attached information are formed, and the end mark detection output from the end mark detecting means is detected in this window pulse, the 0 data detection is performed. The above-mentioned problem is solved by having an attached information detecting means for outputting attached information from the means.

The accessory information detecting device according to the present invention is
It is characterized in that it has second 0-data detecting means for detecting attached information having 0-data longer than 0-data detected by the 0-data detecting means and for outputting the attached information when this is detected. Solve the problem of.

[0035]

In the accessory information detecting apparatus according to the present invention, when the sync signal detecting means detects the sync signal recorded at the head portion of the accessory information, this detection output is supplied to the accessory information reproducing means. The attached information reproduction means is retriggered by the detection output from the synchronization signal detection means, and reproduces the attached information recorded after the synchronization signal until the next detection output is supplied.

On the other hand, the window pulse forming means forms a window pulse for detecting an end mark indicating the recording end position of the attached information based on the detection output from the synchronizing signal detecting means, and detects the end mark. Supply to the means. The end mark detecting means supplies an end mark detection output to the attached information reproduction control means when the end mark is detected in the window pulse from the window pulse forming means. When the end mark detection output is supplied from the end mark detection means, the attached information reproduction control means reproduces the attached information so as to stop the reproduction operation of the attached information until the next synchronization signal is detected. Control means.

With this, reproduction can be performed for each data block in which a time code or the like is recorded, and additional information having the data block, that is, a video marker, an instrument coding index, a one-block video subcode and Ancillary information such as a 5-block video subcode can be read.

Further, the attached information detecting apparatus according to the present invention is
The first 0 data detecting means detects the length of 0 data continuously recorded in the first half portion of the attached information, and when the length of the 0 data is a predetermined length, the attached data is attached. Information is supplied to the auxiliary information detecting means. The attached information detecting means forms a window pulse for detecting an end mark indicating the recording end position of the attached information, and when the end mark detection output from the end mark detecting means is detected in this window pulse, The auxiliary information from the 0 data detecting means is output.

This makes it possible to read, for example, 0 data of a predetermined length, that is, attached information such as a video marker having a search mark, a 1 block video subcode, a 5 block video subcode, and the like.

The accessory information detecting device according to the present invention is
The second 0-data detecting means detects attached information having 0-data longer than the 0-data detected by the 0-data detecting means, and outputs the attached information when this is detected.

As a result, there is 0 data longer than the search mark, and there is no end mark, for example, 0 data.
The index can be detected.

[0042]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an attached information detecting device according to the present invention will be described below with reference to the drawings.

The attached information detecting apparatus according to the present embodiment has the above-mentioned 0 index, instrument coding index, video marker, 5 block video subcode, 1
It is an accessory information detection device that detects accessory information that is a block video subcode, and as shown in FIG. 1, it performs NRZ (Non Return to Zero) conversion of accessory information such as 0 indexes and video markers reproduced from an 8 mm video tape. N
From the RZ conversion circuit 1 and the attached information above, 1.5T (T is 1
A signal (hereinafter, simply referred to as 1.
It is called 5T pulse. 1.) 1.5T pulse detection circuit 2 for detecting 1) and a window pulse for forming a detection area of a signal having a pulse width of 1.5T.
A 5T pulse detection area generator (hereinafter, simply referred to as a generator) 3, a first 0 detection circuit 4 for detecting a 0 index from the attached data from the NRZ conversion circuit 1, and attached data from the NRZ conversion circuit 1. And a second 0 detection circuit 5 for detecting a search mark.

Further, the attached information detecting device forms a window pulse for detecting an end mark of a video marker, an instrument coding index, a 1-block video subcode and a 5-block video subcode, which will be described below. Second end mark detection circuit 11
The detection signal from the first end mark detection circuit 6 for detecting the 5 block video sub-code, 1 block video sub-code and video marker based on the OK pulse from First gated by window pulse from generator 3
AND gate 20, a sync detection circuit 7 for detecting the sync signal from the gate output from the first AND gate 20, and an error detection control signal described later based on the detection signal from the sync detection circuit 7. (CRCC control signal), a write control pulse, and a timing generator 8 for forming and outputting a window pulse for forming an area for detecting an end mark.

The attached information detecting device further includes a second AND gate 10 which gates the gate output from the first AND gate in response to the window pulse from the timing generator 8 and the second AND gate. 1
The end mark is detected by detecting whether or not a predetermined number of the 1.5T pulses are present in the gate output from 0, and when the predetermined number of the 1.5T pulses is present, the generator 3 is reset. In addition, when the first end mark detection circuit 6 outputs an OK pulse for detecting the end mark of the 5-block video subcode and the 1-block video subcode, and the predetermined number of 1.5T pulses does not exist. Has a second end mark detection circuit 11 that outputs an NG pulse.

Further, the attached information detecting device detects an error in the attached data from the NRZ conversion circuit 1 by the CRCC control signal from the timing generator 8 and indicates when the attached data has an error. NG
An error detection circuit 9 that outputs a pulse, an OR gate 12 that forms and outputs a clear signal when NG pulses are supplied from the error detection circuit 9 and the second end mark detection circuit 11, respectively, and the clear signal. The stored contents are cleared by the writing control signal from the timing generator 8 to control the writing of the attached data from the NRZ conversion circuit 1, and the reading control signal from the system controller described later controls the reading of the attached data. And a buffer memory 13 to be operated.

The attached information detecting apparatus according to this embodiment having such a structure can be applied to a so-called 8 mm video tape recorder apparatus as shown in FIG. 2, for example. In FIG. 2, the attached information detecting device functions as the subcode decoder 41. Further, the 8 mm video tape recorder device records a video subcode (1 block video subcode or 5 block video subcode) as the additional information at the time of recording, but at the time of reproduction, the 0 index and instrument coding index are recorded. , Video marker, 5-block video subcode, and 1-block video subcode can be detected.

First, in the case of recording a recording signal (video signal, audio signal and auxiliary information) in the 8 mm video tape recorder shown in FIG. 2, the video signal is subjected to a predetermined modulation processing by the video signal processing circuit 30. And is supplied to the amplifier circuit 32.

Further, the audio signal is subjected to PCM processing by the PCM audio signal processing circuit 31 and supplied to the selected terminal 33b of the changeover switch 33.

On the other hand, a 5-block video subcode (or 1-block video subcode) indicating the index, time code, recording date, etc. corresponding to the above video signal and audio signal is formed by the system controller 39.
It is supplied to the subcode encoder 40. The sub-code encoder 40 performs an encoding process on the 5-block video sub-code and outputs the encoded process to the changeover switch 33.
To the selected terminal 33c.

When the rotary head 34 traces the PCM audio signal recording area shown in FIG. 7, the changeover switch 33 selects the selected terminal 33b by the selection control pulse from the timing generator 42. When the rotary head 34 traces the attached information recording area shown in FIG. 7, the selected terminal 33a is used to select the selected terminal 33c.
Is controlled to be selected.

As a result, the rotary head 34 moves to the P
When tracing the CM audio signal recording area, the PC
The PCM audio signal from the M audio signal processing circuit 31 is supplied to the amplifying circuit 32 through the changeover switch 33, and when the rotary head 34 traces the attached information recording area, 5 from the subcode encoder 40 is used. The block video subcode is supplied to the amplifier circuit 32 via the changeover switch 33.

The amplifier circuit 32 is provided with the video signal, PC
The M audio signal and the 5-block video subcode are respectively amplified with a predetermined gain and supplied to the rotary head 34.

As a result, as shown in FIG. 7, the video signal for one field, the 5-block video subcode, and the PCM audio signal are one track and are recorded on an 8 mm video tape (hereinafter, simply referred to as a magnetic tape) 35. Will be recorded.

Next, the recording signal thus recorded on the magnetic tape 35 is reproduced by the rotary head 34.

The rotation speed of the rotary head 34 is detected by the pulse generator 36. The pulse generator 36 supplies a PG pulse indicating the rotation speed of the rotary head 34 to the switching pulse generator 37.
The rotary head 34 has, for example, a so-called two-head configuration having heads at opposite positions,
The switching pulse generator 37 is provided in the amplifier circuit 32, the timing generator 42, and the PCM audio signal processing circuit 31 so that the signal processing corresponding to the head tracing the track among the two heads is performed. Supply switching pulses.

As a result, the video signal reproduced by the rotary head 34 is amplified by the amplifier circuit 32 based on the switching pulse, and the video signal processing circuit 3 is amplified.
Supplied to zero. The video signal processing circuit 30 performs a predetermined demodulation process on the video signal and supplies the demodulated signal to a monitor device or the like (not shown). As a result, an image corresponding to the video signal is displayed on the display screen of the monitor device.

Further, the PCM audio signal and the 5-block video subcode are amplified by the amplifier circuit 32 based on the switching pulse, and the PLL (phase
(Locked loop) circuit 38.

The PLL circuit 38 outputs the PCM audio signal and the PLL clock to the PCM audio signal processing circuit 31.
And the 5 block video subcode together with the PLL clock to the subcode decoder 41.

The PCM audio signal processing circuit 31 demodulates the PCM audio signal and supplies it to the speaker device or the like in the monitor device. As a result, the speaker device produces sound according to the PCM audio signal.

The timing generator 42 supplies the switching pulse from the switching pulse generator 37 to the subcode decoder 41.

The sub-code decoder 41 uses the PL
The 5-block video subcode is decoded based on the L clock and the switching pulse and is supplied to the system controller 39. The system controller 39 supplies auxiliary information such as recording date and time code indicated by the 5-block video subcode to the monitor device and the like. As a result, the recording date of the image is displayed on the display screen of the monitor device together with the image corresponding to the video signal.

Next, the sub information decoder 41, which is the sub-code decoder 41 according to the present embodiment, has a 0 index,
It is possible to detect all instrumental information such as instrument coding index, video marker, 5-block video subcode, and 1-block video subcode.

That is, in FIG. 1, the auxiliary information from the PLL circuit 38 is supplied to the NRZ conversion circuit 1 and the 1.5T pulse detection circuit 2 via the input terminal 14. Further, the switching pulse from the switching pulse generator 37 is supplied to the generator 3 via the input terminal 15.

The accessory information detecting device shown in FIG. 1 has the PLL circuit 3 supplied through the input terminal 22.
It operates based on the PLL clock from 8.

The NRZ conversion circuit 1 performs an NRZ conversion process on the attached information and supplies it to the first 0 detection circuit 4, the second 0 detection circuit 5, the error detection circuit 9 and the buffer memory 13.

The 1.5T pulse detection circuit 2 is shown in FIG.
As shown in (1), the sync signal recorded at the beginning of the data of the ancillary information, which is a repetitive pulse of 1.5T + 1.5T, and the signal having one set of 1.5T + 1.5T as one set
An end mark recorded at the end of each piece of data of the above-mentioned attached information, which is formed by recording two sets (total 24 shots of 1.5T), is detected, and this detection signal is supplied to the first AND gate 20.

Further, the generator 3 is reset by an OK pulse from the second end mark detection circuit 11 which will be described later, and a window pulse for detecting the sync signal and the end mark based on the switching pulse. It is formed and is supplied to the first AND gate 20.

When the sync signal and the end mark are detected in the window indicated by the window pulse, the first AND gate 20 supplies them to the sync detection circuit 7 and the second AND gate 10. .

The synchronization detection circuit 7 detects the number of 1.5T pulses that are continuously supplied. When the number of pulses is less than 24 (end mark), the timing generator 8 is retriggered immediately after counting the 24 pulses, assuming that the synchronization signal is supplied. The number of 1.5T pulses that are continuously supplied and detected by the synchronization detection circuit 7 may be set to 24 or less, such as 18 (9 sets).

When the timing generator 8 is retriggered, it supplies a CRCC control signal to the error detection circuit 9, a write control signal to the buffer memory 13, and a sync signal and a sync signal to the second AND gate 10. A window pulse for detecting the end mark is supplied.

The auxiliary data supplied from the NRZ conversion circuit 1 is written in the buffer memory 13 based on the write control signal.

Further, the error detection circuit 9 uses the CRC
When the C control signal is supplied, error detection of the attached data supplied from the NRZ conversion circuit 1 is performed. The NG pulse is turned on only when an error in the attached data is detected.
Supply to the R gate 12.

When the second AND gate 10 detects the sync signal and the end mark in the window pulse, they supply them to the second end mark detection circuit 11.

The second end mark detecting circuit 11 is
The number of consecutive 1.5T pulses is counted, and when 24 or more consecutive pulses are detected, an OK pulse is assumed to be supplied as an end mark, and an OK pulse will be described later. Supply to the generator 3.

The generator 3 is reset when the OK pulse is supplied, and the first AND gate 2
The window pulse supply to 0 is stopped. When the supply of the window pulse is stopped, the first AND gate 20 gates the sync signal and the end mark from the 1.5T pulse detection circuit. Then, when the switching pulse supplied via the input terminal 15 changes (the switching pulse changes when switching from one head provided at the opposite position to the other head), again. The window pulse is supplied to the first AND gate 20. As a result, the detection of the sync signal and the end mark is restarted.

On the other hand, the second end mark detection circuit 1
1 outputs an NG pulse when the OK pulse is not output, that is, when reading data in which the end mark is not detected, and supplies this to the OR gate 12.

In the OR gate 12, in addition to the NG pulse from the second end mark detection circuit 11 as described above, in the error detection circuit 9, an error in the attached data from the NRZ conversion circuit 1 is detected. If detected, an NG pulse is delivered. When the NG pulse is supplied from each of the error detection circuit 9 and the second end mark detection circuit 11, the OR gate 12 forms a clear pulse as if erroneous auxiliary data was supplied during data reading, This is supplied to the buffer memory 13.

The attached data written in the buffer memory 13 is read by a read control signal supplied from the system controller 39 shown in FIG. 1 via the input terminal 19 and via the attached data output terminal 18. When supplied to the system controller 39, the buffer memory 13 clears the attached data stored in the memory when the clear pulse is supplied. As a result, it is possible to prevent the incorrect output of the attached data.

The system controller 39 is
The accessory data supplied via the accessory data output terminal 18 is supplied to the monitor device or the like. As a result, the recording date, time code, etc. are displayed on the display screen of the monitor device together with the image corresponding to the video signal.

In this way, by retriggering the timing generator 8 at the timing when the sync signal is supplied by the sync detection circuit 7, the 1 block video subcode, the video marker, the 5 block video subcode and the instrument coding You can read the data in the index.

Specifically, as shown in FIG. 3A, the 1-block video subcode and the video marker are 0.
One data block recorded over 14H,
This data block is composed of an end mark recorded over 0.1H in the subsequent stage.

As described above, the timing generator 8 is retriggered at the timing when the sync signal recorded at the head portion of the data block is detected. The timing generator 8 clears the count value when the retrigger is performed, and counts 0.14H (data block) from here. And the above 0.14
After counting H, a window pulse of 0.1H (end mark) is formed and supplied to the second AND gate.

As a result, the data of one block and the end mark can be accurately detected, and the one-block video subcode and the video marker can be accurately read.

Next, as shown in FIG. 3B, the 5-block video subcode has five data blocks (block 0 to block 4) recorded over 0.14H, and the data block is provided in the subsequent stage. It consists of an end mark recorded over 0.1H.

As described above, the timing generator 8 is retriggered at the timing when the sync signal recorded at the head portion of the data block is detected.
The timing generator 8 clears the count value when the retrigger is performed, and counts 0.14H (data block) from here. Therefore, the count value of the timing generator 8 is cleared for each of the data blocks, and after counting 0.14H in the fifth data block (block 4), the count value of 0.
A window pulse of 1H (end mark) can be formed and supplied to the second AND gate.

As a result, it is possible to accurately detect the data and end mark of the above five blocks, and
The block video subcode can be read accurately.

Next, as shown in FIG. 3C, the instrument coding indexes are each 0.14.
It consists of 6 data blocks (block 0 to block 5) recorded over H and end marks recorded in the subsequent stage of this data block.

As described above, the timing generator 8 is retriggered at the timing when the sync signal recorded at the head portion of the data block is detected.
The timing generator 8 clears the count value when the retrigger is performed, and counts 0.14H (data block) from here. Therefore, the count value of the timing generator 8 is cleared for each of the data blocks, and after counting 0.14H in the sixth data block (block 5), 0.
A window pulse of 1H (end mark) can be formed and supplied to the second AND gate.

As a result, the data and end marks of the above six blocks can be detected accurately, and the instrument coding index can be detected accurately.

Next, the attached information detecting apparatus according to the present embodiment accurately corrects only the newly recorded attached information even if there is previously attached attached information and newly attached attached information. Can be detected.

For example, when a new 1-block video subcode is recorded at a place where a 5-block video subcode is recorded as shown in FIG.
The end mark of the block video subcode is erased by the one block video subcode. For this reason, since the end mark does not exist even if the 5-block video subcode is first read, the NG pulse is output from the second end mark detection circuit 11 shown in FIG. 1 and the stored contents of the buffer memory 13 are cleared. Will be done. Therefore, only the 1-block video subcode newly stored and having the end mark can be accurately detected.

Further, as shown in FIG. 4 (b), a new 1
If the block video sub-code is recorded and both end marks remain, the newly recorded 1-block video sub-code is correctly detected because of the end mark, and the second end shown in FIG. 1 is detected. An OK pulse is supplied from the mark detection circuit 11 to the generator 3. The generator 3 is reset by the OK pulse and stops the supply of the window pulse to the first AND gate 20, so that the data of the one-block video subcode recorded before is stored in the first AND gate 20.
It will be gated at and will not be detected. Therefore, even if both the previously recorded accessory data and the newly recorded accessory data have end marks, only the newly recorded accessory data can be accurately detected.

Next, the second 0 detection circuit 5 shown in FIG.
Continuously recorded "0" forming a search mark
The video marker, the 1-block video subcode, and the 5-block video subcode are detected by detecting the length of the.

That is, the search mark of the video marker is "0" over 1.26H as shown in FIG.
Is recorded, and the search marks of the above 5 block video subcode and 1 block video subcode are shown in FIG.
2, "0" is recorded over 1.0H as shown in FIG.

The second 0-detection circuit 5 detects 1.0H to 10% from the attached data supplied from the NRZ conversion circuit 1.
When continuous "0" detection up to 1.26H is performed and ancillary data satisfying this condition is supplied, it is detected as a video marker, 5 block video subcode or 1 block video subcode, and the first end mark is detected. Supply to the circuit 6.

Here, as shown in FIG. 5 (a), for example, when a new 1-block video subcode is recorded on the previously recorded 5-block video subcode, the length of 1.0H is set. The search mark may remain and may be erroneously detected.

For this reason, the first end mark detection circuit 6 detects the 0. 0 mark for detecting the end mark of the video marker, the 1 block video subcode and the 5 block video subcode as shown in FIG. Form an 8H window pulse. Only when the OK pulse output when the second end mark detection circuit 11 detects the end mark of the attached data is detected within the window pulse, the attached data currently supplied is the video marker. Output terminal 1 as 5 block video subcode or 1 block video subcode
7 to the system controller 39.

As a result, as shown in FIG.
Even if the search mark with a length of 0H is left as it is, there is no end mark, so the 1-block video subcode with the end mark can be accurately detected without detecting the 5 block video subcode recorded before. Can be detected.

Further, as shown in FIG. 5B, both the search mark and the end mark of the previously recorded 1-block video subcode and the newly recorded 1-block video subcode remain, and When the recorded 1-block video subcode is recorded before the preceding 1-block video subcode, the second end of the second end of the first end mark detection circuit 6 within the 0.8H window pulse is recorded. OK from the end mark detection circuit 11
When the pulse is detected, the OK pulse is supplied to the generator 3, so that the supply of the window pulse to the first AND gate 20 is stopped. Therefore, the sync detection circuit 7 does not detect the sync signal, and the previously recorded 1-block video subcode is not detected. Therefore, even in this case, only the newly recorded 1-block video subcode can be accurately detected.

As described above, in the accessory information detection device according to the present embodiment, the second 0 detection circuit 5 detects 1.0H to 1.2 from the accessory data supplied from the NRZ conversion circuit 1.
The continuous "0" detection up to 6H is performed, and the first end mark detection circuit 6 forms a window pulse for detecting the end mark of the video marker, the 1 block video subcode and the 5 block video subcode. , Only when the OK pulse from the second end mark detection circuit 11 is detected in this window pulse,
Since the auxiliary data is output from the second 0 detection circuit 5, the video marker, the 5-block video subcode or the 1-block video subcode can be accurately detected.

Next, the first 0 detection circuit 4 shown in FIG.
Of the attached data from the NRZ conversion circuit 1, 1.2
Continuous detection of "0" longer than 6H is performed. That is, the 1-block video subcode and the 5-block video subcode have "0" recorded continuously for 1.0H, and the video marker has "0" recorded continuously for 1.26H. Further, as shown in FIG. 6, as the 0 index, “0” is continuously recorded in the PCM postamble for 1.5H.

Therefore, the first 0 detection circuit 4 can detect the 0 index by detecting continuous "0" longer than 1.26H.

It should be noted that the first 0 detection circuit 4 is connected to the 0
When the index is detected, it is supplied to the system controller shown in FIG. 2 via the output terminal 16.

As is apparent from the above description, the attached information detecting apparatus according to the present embodiment has a plurality of attached information, that is, 0 index, instrument coding index, video marker, 1 block video subcode and 5 blocks. Each video subcode can be detected accurately. Therefore, since any attached data can be detected, compatibility between devices that handle 8 mm video tapes can be improved, which can contribute to the spread of devices that handle the 8 mm video tapes.

In the description of the above embodiment, specific numerical values such as the length of the search mark being 1.0H have been described, but this is an example, and the NTSC system and the PAL system. Of course, it can be changed according to the video system such as.

[0107]

The attached information detecting apparatus according to the present invention can accurately detect a plurality of attached information. For this reason,
Since any attached information can be detected, compatibility between devices that handle the attached information can be improved. In addition, it is possible to contribute to the spread of devices that handle the attached information.

[Brief description of drawings]

FIG. 1 is a block diagram of an attached information detection device according to an embodiment of the present invention.

FIG. 2 is a block diagram when the attached information detection device according to the above embodiment is applied to an 8 mm video tape recorder device.

FIG. 3 is a schematic diagram for explaining a detection operation of a 1-block video subcode, a video marker, a 5-block video subcode, and an instrument coding index of the attached information detection device according to the above embodiment.

FIG. 4 is a schematic diagram for explaining an operation of detecting attached information relating to old and new recordings of the attached information detecting apparatus according to the embodiment.

FIG. 5 is a schematic diagram for explaining an operation of detecting attached information relating to old and new recordings of the attached information detecting apparatus according to the embodiment.

FIG. 6 is a schematic diagram for explaining a 0-index detection operation of the attached information detection device according to the embodiment.

FIG. 7 is a schematic diagram showing record information of one track recorded on an 8 mm video tape.

FIG. 8 is a diagram showing a recording format of 0 index.

FIG. 9 is a diagram showing a recording format of an instrument coding index.

FIG. 10 is a diagram for explaining a synchronization signal recorded at the beginning of data of attached information.

FIG. 11 is a diagram showing a recording format of a video marker.

FIG. 12 is a diagram showing a recording format of a 5-block video subcode.

FIG. 13 is a diagram showing a recording format of a 1-block video subcode.

FIG. 14 is a schematic diagram for explaining the operation of detecting the attached information of the conventional attached information detecting device.

[Explanation of symbols]

1 ... NRZ conversion circuit 2 ... 1.5T pulse detection circuit 3 ...・ 1.5T detection area generator 4 ・ ・ ・ ・ ・ ・ ・ ・ First 0 detection circuit 5 ・ ・ ・ ・ ・ ・ ・ ・ Second 0 detection circuit 6 ・ ・・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ First end mark detection circuit 7 ・ ・ ・ ・ ・ ・ ・ ・ Synchronization detection circuit 8 ・ ・ ・ ・ ・ ・ ・ ・Generator 9: Error detection circuit 10: Second AND gate 11 :: 2 end mark detection circuit 12 ... OR gate 13 ... buffer memory 20 ... AND gate 30 of 1 ... ··· Video signal processing circuit 31 ······ PCM audio signal processing circuit 32 ····· Amplifying circuit 33 ···・ ・ ・ ・ Changeover switch 34 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Rotating head 35 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 8mm video tape 36 ・ ・ ・ ・ ・ ・Pulse generator 37 ... Switching pulse generator 38 ... PLL circuit 39 ... System controller 40 ...・ ・ ・ ・ ・ ・ ・ Subcode encoder 41 ・ ・ ・ ・ ・ ・ ・ Subcode decoder 42 ・ ・ ・ ・ ・ ・ ・ Timing generator

Claims (3)

(57) [Claims] 1. An accessory information detection device for detecting accessory information recorded together with record information on a recording medium, comprising: a sync signal detecting means for detecting a sync signal recorded at a head portion of the accessory information; Attached information reproducing means for reproducing attached information recorded after the synchronizing signal until retriggered by the detected output from the synchronizing signal detecting means and then supplying the detected output, and the synchronizing signal detecting means. Window pulse forming means for forming an end mark indicating the recording end position of the additional information based on the detection output from the window pulse forming means, and the end mark detected in the window pulse from the window pulse forming means. The end mark detection means for outputting an end mark detection output when the When the mark detection output is supplied, the auxiliary information reproduction control means for controlling the additional information reproduction means to stop the reproduction operation of the additional information until the next synchronization signal is detected. Attached information detection device. 2. The length of 0 data continuously recorded in the first half of the attached information is detected, and the attached information is output when the length of the 0 data is a predetermined length. When a window pulse for detecting the end mark indicating the recording end position of the additional information is formed and the end mark detection output from the end mark detecting means is detected within this window pulse. The adjunct information detecting device according to claim 1, further comprising: adjunct information detecting means for outputting adjunct information from the 0 data detecting means. 3. A second 0, which detects attached information having 0 data longer than the 0 data detected by the 0 data detection means, and outputs this attached information when detected.
The attached information detection device according to claim 1 or 2, further comprising data detection means.