JPS5860408A - Signal processing circuit of recording and reproducing device - Google Patents

Abstract

PURPOSE:To eliminate disturbance due to a flaw in and dust on a recording medium by transforming every segment signal, segmented as prescribed, into a frequency domain through prescribed algorithm and then transforming a reproduced signal into a time domain through reverse algorithm. CONSTITUTION:A recording signal processing circuit 12 is supplied with a video signal from a recording signal source 11, adjusts it to an adequate level to perform preemphas is processing, and segments the signal at adequate intervals of time to store segment signals temporarily. The segment length is set much longer than the time when disturbance due to a flaw, dust, etc., is applied during the signal reproduction of a magnetic recording medium 15. An arithmetic device 13 transforms each segment input into a frequency domain by CZT (chirp Z transformation) algorithm, etc., and the output is recorded on the medium 15 through a recording signal preprocessing circuit 14. A signal reproduced from the medium 15 is supplied through a reproduced-signal preprocessing circuit 16 to a reverse CZT17, which transforms the input signal into a time domain by reverse CZT algorithm, etc. Then, the resulting signal is supplied to a reproduced signal processing circuit 18, thus performing the reproduction stable against the disturbance due to a flaw, sticking dust, etc.

Description

【発明の詳細な説明】 本発明は記録再生装置の信号処理回路に関する。[Detailed description of the invention] The present invention relates to a signal processing circuit for a recording/reproducing device.

記録再生装置、たとえばビデオテールレコーダ（以下Ｖ
ＴＲと略称する）において、記録信号（映像信号）は時
間軸に対して１対１でテープに記録されている。従って
、再生時にテープ上に傷があったり、あるいはごみが付
着していると、テープ上のこの部分で再生信号が一時途
切れ、この間は映像情報は全て失なわれてし捷い、雑音
が発生して内生画面が見苦しくなる。Recording and reproducing devices, such as video tail recorders (hereinafter referred to as V
(abbreviated as TR), recording signals (video signals) are recorded on a tape one-to-one with respect to the time axis. Therefore, if there are scratches or dust on the tape during playback, the playback signal will be temporarily interrupted at this part of the tape, and during this time all video information will be lost and noise will occur. The internal screen becomes unsightly.

本発明は上記の事情に鑑みてなされたもので、記録媒体
上に傷、ごみの伺着等の外乱があっても安定した再生信
号を得ることが可能な記録再生装置の信号処理回路を提
供するものである。The present invention has been made in view of the above-mentioned circumstances, and provides a signal processing circuit for a recording/reproducing device that is capable of obtaining a stable reproduction signal even when there are disturbances such as scratches or dirt on the recording medium. It is something to do.

以下、図面を参照して本発明の一実施例を詳細に説明す
る。Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

図において、２２はたとえは映像信号を発生する記録信
号源でおる。１２はこの映ｆ象伯号を適当なレベルに調
整してプリエンファシス処理し、信号を適当な時間間隔
で区切ってそれぞれ一時記憶しておくための記録信号処
理回路である。ここで区切られた信号それぞれをセグメ
ントと称するものとし、このセグメントの長さを後述す
る磁気記録媒体Ｉ５の信号再生時において媒体上の傷、
ごみの付着等にょる外乱が加わる時間（予め判明してい
る）に対して十分長くしておく。Ｉ３け信号入力を時間
ドメインから周波数ドメインに変換する演η器、たとλ
げＣＺＴ　（チャー７’Ｚ）ランスフォーメーション）
であり、各セグメント入力毎にＣＺ’ｌ”ア／ｌ−Ｊ″
′リズム等により周波数ドメインに変換りるものである
。Ｉ４はこのＣＺＴ　７３からの記録信号を前処理する
記録信号前処理回路であり、この回路１４の出力信号が
磁気テープ等の磁気記録媒体Ｉ５に記録されるようにな
っている。ｒｅｌｒＪこの記録媒体Ｉ５から再生される
Ｉｉｊ生信号を前処理する再生信号前処理回路である。In the figure, 22 is a recording signal source that generates a video signal. Reference numeral 12 denotes a recording signal processing circuit for adjusting the video signal to an appropriate level, pre-emphasizing the signal, dividing the signal at appropriate time intervals, and temporarily storing each signal. Each of the signals divided here is called a segment, and the length of this segment is determined by the scratches on the medium during signal reproduction of the magnetic recording medium I5, which will be described later.
The time should be made long enough for the time (known in advance) during which disturbances due to adhesion of dust etc. will be added. A deductor that converts the input signal from the time domain to the frequency domain, and
GeCZT (Char7'Z) Transformation)
, and for each segment input CZ'l"A/l-J"
'It is converted into the frequency domain by rhythm, etc. I4 is a recording signal preprocessing circuit that preprocesses the recording signal from this CZT 73, and the output signal of this circuit 14 is recorded on a magnetic recording medium I5 such as a magnetic tape. relrJ is a reproduction signal preprocessing circuit that preprocesses the Iij raw signal reproduced from this recording medium I5.

７７＆：ｔこの前処理回路Ｚ６からの再生信号を逆ＣＺ
Ｔアルゴリズム等により時間ドメインに変換する逆ＣＺ
’ｌ”である。１Ｂはこの逆ＣＺＴ　７７からの、ｒＩ
ｊ生信号を適当なレベルに調整し、デエンファシス等の
処理を施し再生出力を得る拘止４ｈ号処理回路である。77&:tThe reproduced signal from this preprocessing circuit Z6 is inverted CZ
Inverse CZ converted to time domain using T algorithm etc.
'l'. 1B is rI from this reverse CZT 77
This is a restraint No. 4h processing circuit that adjusts the j raw signal to an appropriate level, performs processing such as de-emphasis, and obtains a reproduced output.

次に、上記構成による動作を計１明する。記録信号源１
１からの映像信号はｌｌｃ’８信号処理回路Ｚ　２　、
　ＣＺＴ　１３　、記録信号前処理回路１４を経て記録
媒体１５に配録される。この際、記録信号は所定の長さ
のセグメントに区切られて周波数ドメインに変換さｆ′
１．でいる。Next, the operation of the above configuration will be explained in detail. Recording signal source 1
The video signal from llc'8 signal processing circuit Z2,
The CZT 13 is distributed to the recording medium 15 via the recording signal pre-processing circuit 14. At this time, the recorded signal is divided into segments of a predetermined length and converted into the frequency domain f′
1. I'm here.

一方５記録媒体１５から再生される信号は再生信号前処
理回路１６．逆ＣＺＴ　７７　、再生信号処理回路Ｉ８
を経て再生される。この際、再生信号は時間ドメインに
変換される。On the other hand, the signal reproduced from the recording medium 15 is processed by the reproduction signal pre-processing circuit 16. Reverse CZT 77, reproduction signal processing circuit I8
It will be played after. At this time, the reproduced signal is converted into the time domain.

而して、再生時に記録媒体Ｉ５上の傷、ごみの付着等に
より再生信号が一時途絶えることがあると、その部分に
相当するセグメントのある周波数成分がなくなり、再生
信号の一部のエネルギが失なわれる。しかし、この失な
われるエネルギは、前記一時途絶える部分に和尚するセ
グメントに分散される。したがって、このような外乱時
に再生信号のエネルギが零になることはなく、失なわれ
た以外の周波数成分のエネルギで再生される。During playback, if the playback signal is temporarily interrupted due to scratches, dust, etc. on the recording medium I5, a certain frequency component of the segment corresponding to that part disappears, and part of the energy of the playback signal is lost. be called. However, this lost energy is distributed to the segments that are connected to the temporary interruption. Therefore, the energy of the reproduced signal does not become zero when such a disturbance occurs, and the reproduced signal is reproduced with the energy of frequency components other than those that were lost.

すなわち、上述したような信号処理回路によれば、再生
時における記録媒体の外乱時に信号エネルギが零になる
ことはなく、従来は信号エネルギが零になっていたこと
に比べて外乱の影響を緩和することができる。このよう
に、信号エネルギが途切れなくなるので、雑音信号の影
響が軽微になり、再生画面の劣化は緩ｆ１１される。In other words, according to the signal processing circuit described above, the signal energy does not become zero when there is a disturbance to the recording medium during playback, and the effect of the disturbance is alleviated compared to the conventional method where the signal energy becomes zero. can do. In this way, since the signal energy is not interrupted, the influence of the noise signal becomes slight, and the deterioration of the reproduced screen is slowed f11.

なお、前記実施例では、磁気記録の場合について説明し
たが５機械ｉピ録（例えばレコード。Incidentally, in the above embodiment, the case of magnetic recording was explained, but 5 machine i-recording (for example, record) was explained.

ディスク）の場合も同様に実施できる。The same method can be used for discs).

本発明は上述したように、記録媒体上に傷５ごみの刺着
等の外乱があっても５安定した再生信号を得ることが可
能な記録内生装置の信号処理回路を提供できる。As described above, the present invention can provide a signal processing circuit for a recording internal reproduction device that is capable of obtaining a stable reproduction signal even if there is a disturbance such as a scratch 5 on the recording medium.

【図面の簡単な説明】[Brief explanation of the drawing]

図面は本発明に係る磁気記録再生装置の信号処理回路の
一実施例を示すブロック図である。 ＩＩ・・・記録信号源、１２・・・記録信号処理回路、
Ｉ３・・・ＣＺＴ、１５・・・磁気記録媒体、１７・・
・逆ＣＺＴ、１８・・・再生信号処理回路、Ｉ４・・・
記録信号前処理回路、１６・・・再生信号前処理回路。 出願人代理人　　弁理士　鈴　江　武　彦　５−The drawing is a block diagram showing an embodiment of a signal processing circuit of a magnetic recording/reproducing apparatus according to the present invention. II...recording signal source, 12...recording signal processing circuit,
I3...CZT, 15...Magnetic recording medium, 17...
・Reverse CZT, 18... Reproduction signal processing circuit, I4...
Recording signal pre-processing circuit, 16... Reproduction signal pre-processing circuit. Applicant's agent Patent attorney Takehiko Suzue 5-

Claims (1)

【特許請求の範囲】[Claims] 記録信号源からの記録信号を所定の時間間隔で区切り、
この区切られた各セグメント信号毎に所定のアルゴリズ
ムにより周波政ドメインに変換したのち記録媒体に記録
する記録信号処理手段と、上記記録媒体から再生された
信号を前記アルゴリズムとは逆のアルゴリズムにより時
間ドメインに変換して再生出力を得る再生信号処理手段
とを具備することを特徴とする記録再生装置の信号処理
回路。Separate the recording signal from the recording signal source at predetermined time intervals,
A recording signal processing means converts each divided segment signal into a frequency domain using a predetermined algorithm and then records it on a recording medium, and converts the signal reproduced from the recording medium into a time domain using an algorithm opposite to the above algorithm. 1. A signal processing circuit for a recording and reproducing apparatus, comprising a reproduced signal processing means for converting the signal into a reproduced signal to obtain a reproduced output.