JP3546431B2 - Disc playback device - Google Patents

Description

【００３５】
ただし、この場合、計算後のデータには誤差が発生し、ＣＤの経過時間等の表示では時間が戻ったりすることもある。このような場合には、計算値が誤差分によって減ることのないようプログラムで対応することにより、不自然な感じを防ぐことができる。
【００３６】
また、アドレス差ΔＡを、数字により、あるいは視覚的な量の表現により、表示部１１に表示することにより、機器の使用者にバッファ用ＲＡＭ６のメモリ残量やメモリ記憶データ量等を知らせることができ、動作状態の確認等に有用である。ここで上記視覚的な量を表現するような表示とは、例えばバッファ用ＲＡＭ６を想起させる容器を表現する固定表示エレメントと、この固定表示エレメントに囲まれる位置に配置されＲＡＭ６に記憶されている再生可能なデータ量を逐一表現する可変表示エレメントとにより実現できる。
【００３７】
次に、各曲毎の先頭位置からの経過時間、いわゆるラップタイムＴ_ＬＡＰ の表示について説明する。このラップタイムＴ_ＬＡＰ については、上記バッファ用ＲＡＭ６での再生可能なデータ量Ｄｍに応じて定まる書込、読出間の時間差（遅延量）Ｔｄを、サブコードＱデータのラップタイムＴ_ＱＬＡＰから引き算して求めることも考えられるが、曲の切り替わりや特殊再生の際等にＴ_ＱＬＡＰとＴ_ＬＡＰ との関係が乱れることを考慮して、サブコードＱデータのラップタイムＴ_ＱＬＡＰは直接使用せずに、サブコードＱデータの絶対時間（アブソリュートタイム）Ｔ_ＱＡＢＳから上記遅延量Ｔｄを減算したものを用いてラップタイムＴ_ＬＡＰ を求めている。
【００３８】
このラップタイムＴ_ＬＡＰ の算出には大別して３種類の計算方法をとっている。すなわち、
（ａ）サブコードＱデータのトラック番号（曲番号）と、バッファ用ＲＡＭ６から読み出して現在再生中の曲（ファイル）のトラック番号が同一の場合。
（ｂ）ノーマル再生中に、曲の切り替わり等により、サブコードＱデータのトラック番号と再生中の曲のトラック番号とが異なる場合。
【００３９】
（ｃ）シャッフルあるいはランダム再生や、プログラム再生、Ａ−Ｂリピート再生等の特殊再生中に、サブコードＱデータのトラック番号と再生中の曲のトラック番号とが異なる場合。
である。
【００４０】
ここで、上記（ａ）〜（ｃ）のいずれの場合にもいえることとして、インデックス番号が「００」のときと「００」以外のときの表示の違いがある。すなわちインデックス番号が「００」とは、曲の先頭位置よりも前の無音部であり、マイナスの数字が表示されて曲の先頭位置で「００：００」（０分０秒）となるように表示数字を変化させることが必要とされる。そして、曲の先頭位置に達するとインデックス番号が「０１」となり、経過時間に応じて増加する数字を表示するわけである。これを図６と共に説明すると、インデックス番号「００」の領域においては、曲の先頭位置ＴＯＰから離れるに従って（図中左方向に向かって）、サブコードＱデータから得られるラップタイムＴ_ＱＬＡＰのフレーム値が「００」から大きくなっており、図示しないが秒の値も０から大きくなっている。従って、再生方向に沿ってインデックス「００」の領域を読み取っている間は、サブコードＱのラップタイムＴ_ＱＬＡＰは０に向かって減っていく値として検出され、曲の先頭位置ＴＯＰに達してインデックス「０１」の領域に入ると、０から増加する値として検出されるようになる。
【００４１】
また、時間情報の内の絶対時間Ｔ_ＱＡＢＳやＴ_ＡＢＳ から曲の先頭位置ＴＯＰからの経過時間であるラップタイムＴ_ＱＬＡＰやＴ_ＬＡＰ を求めるためには、先ず曲の先頭位置ＴＯＰ、すなわちインデックス番号が「０１」でラップタイムＴ_ＱＬＡＰが「００：００．００」（０分０秒０フレーム）の位置での絶対時間である先頭位置時間（以下トップタイムという。）Ｔ_ＴＯＰ を求めることが必要とされる。このトップタイムＴ_ＴＯＰ は、サブコードＱデータから得られる絶対時間Ｔ_ＱＡＢＳ及びラップタイムＴ_ＱＬＡＰによって、
インデックス番号「００」のとき：
Ｔ_ＴＯＰ ＝Ｔ_ＱＡＢＳ＋Ｔ_ＱＬＡＰ＋００：００．０１ ・・・（２）
インデックス番号「００」以外のとき：
Ｔ_ＴＯＰ ＝Ｔ_ＱＡＢＳ−Ｔ_ＱＬＡＰ ・・・（３）
の各式により計算される。上記（２）式中の「００：００．０１」は、図６のインデックス「００」の領域内で、上記先頭位置ＴＯＰの直前フレームが「００」となっていることを考慮したものである。このようなトップタイムＴ_ＴＯＰ を、曲が替わる毎に計算して求めてメモリ等にセーブしておく。
【００４２】
また、上記バッファ用ＲＡＭ６での遅延量（書込、読出の間の時間差）ＴｄとサブコードＱデータの絶対時間Ｔ_ＱＡＢＳとから、再生中のメインデータの絶対時間Ｔ_ＡＢＳ を、
Ｔ_ＡＢＳ ＝Ｔ_ＱＡＢＳ−Ｔｄ ・・・（４）
の式により求める。この現在再生中の絶対時間Ｔ_ＡＢＳ が、上記（２）、（３）式により求められたトップタイムＴ_ＴＯＰ の前か後かを判断する。前であればインデックス番号が「００」、後であればインデックス番号が「００」以外と判別することができる。また、この（４）式から求められた再生中の絶対時間Ｔ_ＡＢＳ と、上記トップタイムＴ_ＴＯＰ 及び後述するエンドタイムＴ_ＥＮＤ とを比較することにより、現在再生中の位置が同一トラック内（同一曲内）か否かを判断している。そして、同一トラック内のとき、すなわち上記（ａ）の場合のとき、現在再生中の位置のインデックス番号に応じて、
インデックス番号「００」以外のとき：
Ｔ_ＬＡＰ ＝Ｔ_ＡＢＳ −Ｔ_ＴＯＰ ・・・（５）
インデックス番号「００」のとき：
Ｔ_ＬＡＰ ＝Ｔ_ＴＯＰ −Ｔ_ＡＢＳ ・・・（６）
により再生中のメインデータのラップタイムＴ_ＬＡＰ を計算し、上記表示部１１に表示させる。
【００４３】
図７は、上記（ａ）の場合の各時間を示す図であり、ディスクから読み取っているデータのサブコードＱのトラック番号（曲番号）Ｎ_ＳＵＢＱと、上記バッファ用ＲＡＭ６から読み出されて現在再生中のメインデータのトラック番号Ｎ_ＰＢとが同一の値「０１」の場合を示している。図８は、上記（ｂ）の場合、すなわちノーマル再生中にサブコードＱデータのトラック番号Ｎ_ＳＵＢＱと再生中の曲のトラック番号Ｎ_ＰＢとが異なる場合を示している。また図９は、上記（ｃ）の場合、すなわち上記特殊再生中にサブコードＱデータのトラック番号Ｎ_ＳＵＢＱと再生中の曲のトラック番号Ｎ_ＰＢとが異なる場合を示している。これらの図においては、説明を簡略化するために、上記遅延量（書込、読出の間の時間差）Ｔｄを一定として図示しているが、実際には高速で間歇的な書込と一定レートでの読出とにより、Ｔｄはダイナミックに変化するものである。
【００４４】
図７に示す上記（ａ）の場合においては、上述した（４）〜（６）式の関係がそのまま当てはまる。この図７において、サブコードＱデータのインデックス番号Ｉ_ＳＵＢＱの「００」と「０１」との境界、すなわち上記曲の先頭位置における絶対時間Ｔ_ＱＡＢＳが上記トップタイムＴ_ＴＯＰ であり、インデックス番号Ｉ_ＳＵＢＱが「００」以外のとき（「０１」、「０２」等のとき）には絶対時間Ｔ_ＱＡＢＳとラップタイムＴ_ＱＬＡＰとの差がこのトップタイムＴ_ＴＯＰ となっている。再生中のメインデータの絶対時間Ｔ_ＡＢＳ は、上記（４）式により、サブコードＱの絶対時間Ｔ_ＱＡＢＳから上記遅延量Ｔｄを減算することで求め、再生中のラップタイムＴ_ＬＡＰ は、上記（５）式により、この再生中の絶対時間Ｔ_ＡＢＳ から上記トップタイムＴ_ＴＯＰ を減算することで求める。このラップタイムＴ_ＬＡＰ を表示する。また、再生中のトラック番号（曲番号）Ｎ_ＰＢやインデックス番号Ｉ_ＰＢが、それぞれ表示用の値（表示トラック番号や表示インデックス番号）とされ、上記図１の表示部１１等に表示される。なお、現在再生中のメインデータのインデックス番号Ｉ_ＰＢが「００」のときには、上記（６）式の計算により、マイナスの値のラップタイムＴ_ＬＡＰ を表示する。
【００４５】
次に、図８に示す上記（ｂ）の場合には、上記（ａ）の場合の表示を行いながら、サブコードＱデータによりトラック番号（曲番号）Ｎ_ＱＳＵＢが切り替わるタイミングを常に監視する。このトラックが切り替わる直前のサブコードＱ絶対時間Ｔ_ＱＳＵＢを、エンドタイムＴ_ＥＮＤ として検出しメモリ等にセーブしておく。そして上記再生中の絶対時間Ｔ_ＡＢＳ がこのエンドタイムＴ_ＥＮＤ に達するまでは、前のトラック番号「０１」のトップタイムＴ_ＴＯＰ１を用いて上記（４）、（５）式の計算を行うことによりラップタイムＴ_ＬＡＰ を求めて表示し、表示トラック番号（再生中のトラック番号Ｎ_ＰＢ）等も前のトラックの数値を保持しておく。再生中の絶対時間Ｔ_ＡＢＳ が上記エンドタイムＴ_ＥＮＤ に達した後には、上記（２）、（３）式により求められたトラック番号「０２」のトップタイムＴ_ＴＯＰ２を用いてラップタイムＴ_ＬＡＰ を計算し、これを表示する。また、このときの再生中のメインデータのトラック番号Ｎ_ＰＢやインデックス番号Ｉ_ＰＢをそれぞれ表示トラック番号や表示インデックス番号として上記表示部１１等に表示する。
【００４６】
次に、図９は上記（ｃ）の場合を示しており、ディスクのアクセス動作のためサブコードＱデータが得られない部分が存在し、サブコードＱの絶対時間Ｔ_ＱＡＢＳは連続していない。このため、アクセス動作中にオンするフラグ（特殊再生フラグ）Ｆ_ＳＰを設け、このフラグＦ_ＳＰを再生中の時間情報等の判断に用いている。この図９では、例えばプログラム再生等において、トラック番号が「０１」のトラックから「０５」のトラックに移動した例を示している。
【００４７】
この図９の場合においては、先ず、上記トラック「０１」での上記エンドタイムＴ_ＥＮＤ を検出してメモリ等にセーブしておく。特殊再生のアクセスでは、目的トラック「０５」のインデックス「０１」の「００：００．００」（０分０秒０フレーム）の位置にアクセスするので、インデックス「００」の領域については再生したり表示したりする必要がない。この場合、上記バッファ用ＲＡＭ６の遅延量（時間差）ＴｄからサブコードＱのラップタイムＴ_ＬＡＰ を減算すれば、現在のトラックの残り時間（以下レストタイムという。）Ｔ_ＲＥＳＴが求められ、このレストタイムＴ_ＲＥＳＴが０となったとき、再生中のメインデータが次の目的トラック「０５」に移ったことになり、上記フラグＦ_ＳＰをオフする。従って、
Ｔ_ＲＥＳＴ＝Ｔｄ−Ｔ_ＱＬＡＰ ・・・（６）
Ｔ_ＡＢＳ ＝Ｔ_ＥＮＤ −Ｔ_ＲＥＳＴ ・・・（７）
Ｔ_ＬＡＰ ＝Ｔ_ＡＢＳ −Ｔ_ＴＯＰ ・・・（８）
の式により、ラップタイムＴ_ＬＡＰ が導き出される。
【００４８】
以上のように絶対時間（アブソリュートタイム）を主に考えているため、いわゆるリメイン表示等も問題なく行える。なお、上記遅延量Ｔｄの値の計算誤差等から、実際の装置において０．２秒程度の誤差が生ずることがあり、上述したような計算により求められたラップタイムＴ_ＬＡＰ 等の値が、その前に求められた値よりも小さくなることがある。そこで、計算されて得られた値を前回の計算値と比較して、大きい方を採用するような工夫を施すことが好ましい。
【００４９】
図１０、図１１は、上述のような３種類の場合におけるラップタイムＴ_ＬＡＰ の計算の手順を説明するためのフローチャートであり、図１０の結合子Ａ、Ｂが、図１１の各結合子Ａ、Ｂと結合される。
これらの図１０、図１１において、最初のステップＳ４１では、上記（１）式による遅延量（時間差）Ｔｄを計算して求める。次にステップＳ４２に進んで、現在特殊再生モード（すなわち例えばシャッフルあるいはランダム再生や、プログラム再生、Ａ−Ｂリピート再生等）であることを示す特殊再生フラグＦ_ＳＰがオンしているか否かを判別する。特殊再生モードでないとき（フラグＦ_ＳＰがオフしているとき）には、上記（ｃ）以外の場合、すなわち上記（ａ）、（ｂ）の場合であり、次のステップＳ４３に進む。
【００５０】
ステップＳ４３では、上記サブコードＱデータから得られた絶対時間Ｔ_ＱＡＢＳから上記遅延量Ｔｄを減算して再生中のメインデータの絶対時間を求めるわけであるが、このときの計算値を直ちにＴ_ＡＢＳ とせず仮の絶対時間Ｔ_ＬＡＢＳとしている。これは、次のステップＳ４４で、前回の計算で求められた絶対時間Ｔ_ＡＢＳ と今回の計算値（上記仮の絶対時間）Ｔ_ＬＡＢＳとを比較して、Ｔ_ＡＢＳ よりＴ_ＬＡＢＳが大きい（Ｔ_ＡＢＳ ＜Ｔ_ＬＡＢＳ）とされたときのみ、次のステップＳ４５でＴ_ＬＡＢＳをＴ_ＡＢＳ とし、それ以外では前回に求められた絶対時間Ｔ_ＡＢＳ をそのまま用いることにより、表示される時間の値が減るような不具合を回避しているものである。すなわち、ステップＳ４４でＹＥＳ（Ｔ_ＡＢＳ ＜Ｔ_ＬＡＢＳ）のときにステップＳ４５で絶対時間Ｔ_ＡＢＳ を更新して次のステップＳ４６に進み、ＮＯのときには直接ステップＳ４６に進んでいる。
【００５１】
ステップＳ４６では、ディスクからのサブコードＱデータのトラック番号（曲番号）Ｎ_ＳＵＢＱが現在再生中のメインデータのトラック番号Ｎ_ＰＢか否かを判別し、ＹＥＳ（同一トラック番号）のときにはステップＳ４７に進む。ステップＳ４７では、再生中のインデックス番号Ｉ_ＰＢが「００」か否かを判別し、ＮＯのときにはステップＳ４８に進む。ステップＳ４８では、サブコードＱのインデックス番号Ｉ_ＳＵＢＱが「００」か否かを判別し、ＮＯのときにはステップＳ４９に進む。ステップＳ４９では、サブコードＱのトラック番号Ｎ_ＳＵＢＱを再生中のトラック番号Ｎ_ＰＢとすると共に、再生中のインデックス番号Ｉ_ＰＢを「０１」としている。これは、インデックス表示を行わない機器の場合に、「０２」以上のインデックス番号もすべて「０１」として取り扱うためである。次のステップＳ５０では、上記（５）式の計算を行って、ラップタイムＴ_ＬＡＰ を求めている。その後、ステップＳ５１に進んで、エンファシスやミュートの制御を行って終了する。
【００５２】
上記ステップＳ４６でＮＯと判別されたとき、すなわちサブコードＱのトラック番号Ｎ_ＳＵＢＱと再生中のトラック番号Ｎ_ＰＢとが異なっているときには、ステップＳ５２に進む。このステップＳ５２では、上記エンドタイムＴ_ＥＮＤ と再生中の絶対時間Ｔ_ＡＢＳ との大小を比較し、エンドタイムＴ_ＥＮＤ がＴ_ＡＢＳ 以上のときには上記ステップＳ５０に進み、エンドタイムＴ_ＥＮＤ がＴ_ＡＢＳ よりも小さいときには、次のステップＳ５３に進んで上記トップタイムＴ_ＴＯＰ の計算を行った後、ステップＳ５４に進む。また、上記ステップＳ４７でＹＥＳ（Ｉ_ＰＢ＝００）とされたときや、上記ステップＳ４８でＹＥＳ（Ｉ_ＳＵＢＱ＝００）とされたときも、ステップＳ５４に進む。このステップＳ５４では、トップタイムＴ_ＴＯＰ が再生中の絶対時間Ｔ_ＡＢＳ 以下か否かの判別を行い、ＹＥＳのときには上記ステップＳ４９に進み、ＮＯのときには次のステップＳ５５に進む。ステップＳ５５では、サブコードＱのトラック番号Ｎ_ＳＵＢＱを再生中のトラック番号Ｎ_ＰＢとすると共に、再生中のインデックス番号Ｉ_ＰＢを「００」としている。次のステップＳ５６では、ラップタイムＴ_ＬＡＰ を計算によって求め、ステップＳ５７に進んで、現在インデックス番号「００」のメインデータを再生中であることを示すフラグＦ_００をオンした後、上記ステップＳ５１に進む。
【００５３】
上記ステップＳ４２においてＹＥＳ（特殊再生フラグＦ_ＳＰがオン）と判別されたときには、図１１のステップＳ６１に進み、上記バッファ用ＲＡＭ６の遅延量ＴｄがサブコードＱデータのラップタイムＴ_ＱＲＡＰ以下か否かを判別する。ＮＯのときには次のステップＳ６２に進み、上記レストタイムＴ_ＲＥＳＴの計算、すなわちＴｄ−Ｔ_ＱＬＡＰの計算を行い、次にステップＳ６３に進んで、上述したステップＳ４３と同様な仮の絶対時間Ｔ_ＬＡＢＳの計算を行う。以下のステップＳ６４、Ｓ６５は、上述したステップＳ４４、Ｓ４５と同様であり、これらのステップＳ６３〜Ｓ６５により、表示される時間の値が減るような不具合を回避している。次のステップＳ６６では、Ｔ_ＡＢＳ −Ｔ_ＴＯＰ の計算によりラップタイムＴ_ＬＡＰ を求め、図１０のステップＳ５１に進む。上記ステップＳ６１でＹＥＳ（Ｔｄ≦Ｔ_ＱＲＡＰ）と判別されたときには、ステップＳ６７に進んで上記特殊再生フラグＦ_ＳＰをオフし、ステップＳ６８にてサブコードＱのトラック番号Ｎ_ＳＵＢＱを再生中のトラック番号Ｎ_ＰＢとすると共に、再生中のインデックス番号Ｉ_ＰＢを「０１」としている。また、次のステップＳ６９で、ラップタイムＴ_ＬＡＰ に「００：００．００」、すなわち０分０秒０フレームを入れた後、図１０の上記ステップＳ５１に進む。
【００５４】
以上の説明からも明らかなように、本実施例によれば、メモリ（バッファ用ＲＡＭ６）にはメインデータを蓄えるだけでよく、メモリ容量が有効に使用でき、なおかつ書込データの情報で読出メインデータをコントロールしたりできる。また、サブコードＱデータによる絶対時間Ｔ_ＱＡＢＳや曲内経過時間（ラップタイム）Ｔ_ＱＬＡＰ等から上記バッファ用ＲＡＭ６での遅延量の時間Ｔｄを減算するだけで、実際に再生されるメインデータに対してタイミングの一致した時間情報（Ｔ_ＡＢＳ やＴ_ＬＡＰ 等）を得ることができ、適切な表示を行わせることができ、バッファ用ＲＡＭ６内の再生可能なデータ量を表示して装置の動作状態を知らせることもできる。また、ディエンファシス切換等の再生データの制御を正しいタイミングで行わせることができる。さらに、曲内の経過時間であるいわゆるラップタイムを表示させる場合に、再生中のトラックがサブコードＱデータのトラックと異なったり、特殊再生モード時であっても、再生中のメインデータの内容に合致したラップタイムを計算で求めることができ、誤差のないラップタイム表示が行える。
【００５５】
なお、本発明は上記実施例のみに限定されるものではなく、例えば、記録媒体としては、光ディスクの他にも、光磁気ディスク、磁気ディスク、磁気テープ等が使用でき、フォーマットもいわゆるＣＤフォーマットに限定されない。また、ＰＣＭオーディオデータ以外に、ビデオデータや、圧縮処理されたデータ等も、上記メインデータとして使用できる。さらに、補助データは上記サブコードデータに限定されず、また誤り訂正処理を行わないようなフォーマットにも適用できる。ハードウェア構成も図示の例に限定されないことは勿論である。
【００５６】
以上の説明からも明らかなように、本発明に係るディスク再生装置によれば、ファイル単位で区切られたメインデータと絶対時間とが記録されたデイスク状記録媒体を再生する再生装置において、上記デイスク状記録媒体から上記メインデータと絶対時間を再生する再生手段と、上記再生手段にて再生された上記メインデータと絶対時間を分離する分離手段と、上記分離手段にて分離されたメインデータを一旦蓄積するバッファ用メモリと、上記バッファ用メモリに上記分離手段にて分離されたメインデータを第１の速度で間欠的に記録し、上記第１の速度より遅い第２の速度で連続的に読み出すメモリ制御手段と、上記バッファ用メモリに書き込まれようとするメインデータの書込アドレスとバッファ用メモリから読み出されようとしている読出アドレスに基づいて遅延量を算出し、上記算出した遅延量と上記分離手段にて分離された絶対時間に基づいて上記バッファ用メモリから読み出されているメインデータの時間情報を算出する算出手段とを備えているため、バッファ用メモリから読み出されたメインデータに対して、正確な対応関係を有する時間情報等を得ることができる。
また、本発明に係るディスク再生装置によれば、ファイル単位で区切られたメインデータと絶対時間と上記ファイル単位の経過時間とが記録されたデイスク状記録媒体を再生する再生装置において、上記デイスク状記録媒体から上記メインデータと絶対時間とファイル単位の経過時間を再生する再生手段と、上記再生手段にて再生された上記メインデータと絶対時間とファイル単位の経過時間を分離する分離手段と、上記分離手段にて分離されたメインデータを一旦蓄積するバッファ用メモリと、上記バッファ用メモリに上記分離手段にて分離されたメインデータを第１の速度で間欠的に記録し、上記第１の速度より遅い第２の速度で連続的に読み出すメモリ制御手段と、上記バッファ用メモリに書き込まれようとするメインデータの書込アドレスとバッファ用メモリから読み出されようとしている読出アドレスに基づいて遅延量を算出し、上記算出した遅延量と上記分離手段にて分離された絶対時間とファイル単位の経過時間とに基づいて上記バッファ用メモリから読み出されているメインデータの時間情報を算出する算出手段とを備えているため、特にファイル毎（曲毎）の経過時間（ラップタイム）を、ファイルの切換時点や特殊再生時等でも正確に求めることができる。
【００５７】
特に、現在再生中のメインデータの絶対時間情報を上記補助データからの絶対時間情報と上記遅延量の時間とに応じて求め、この再生中のメインデータの絶対時間から現在再生中の曲（ファイル）の先頭位置の絶対時間から減算することで、曲内（ファイル内）経過時間、いわゆるラップタイムを容易かる正確に求めることができる。
【００５８】
また、上記記録媒体上の複数のファイルを連続して再生する際に、上記バッファ用メモリから読み出されるメインデータのファイルの境界位置で、旧ファイルの識別情報から新ファイルの識別情報に更新することにより、ファイル識別情報（曲番号）も再生中のメインデータに一致させて表示することができる。
【００５９】
さらに、メインデータに補助データが付加された記録データを記録媒体から読み出して上記メインデータを分離し、バッファ用メモリに対して書込／読出を制御しているため、上記バッファ用メモリにはメインデータのみを蓄えればよく記憶容量の有効利用率を高めることができる。
【図面の簡単な説明】
【図１】本発明に係るディスク再生装置の一実施例の全体の概略構成を示すブロック図である。
【図２】上記実施例中の信号処理部の具体例を示すブロック回路図である。
【図３】上記実施例中のＲＡＭコントローラの具体例及びその周辺を示すブロック回路図である。
【図４】上記実施例中のバッファ用ＲＡＭのメモリ空間上での書込アドレス及び読出アドレスの移動を説明するための図である。
【図５】上記図３中のアドレス生成回路の内部構成の一例を示すブロック図である。
【図６】インデックス番号とフレームとの関係を説明するための図である。
【図７】サブコードＱデータのトラック番号と再生中のトラック番号とが同一の場合の各時間情報を示す図である。
【図８】通常再生時にサブコードＱデータのトラック番号と再生中のトラック番号とが異なる場合の各時間情報を示す図である。
【図９】特殊再生時にサブコードＱデータのトラック番号と再生中のトラック番号とが異なる場合の各時間情報を示す図である。
【図１０】上記実施例の動作を説明するためのフローチャートである。
【図１１】上記実施例の動作を説明するためのフローチャートである。
【符号の説明】
１・・・・・光ディスク
２・・・・・光ピックアップ
４・・・・・信号処理部
５・・・・・ＲＡＭコントローラ
６・・・・・バッファ用ＲＡＭ
９・・・・・サーボ制御回路
１０・・・・・システムコントローラ
１１・・・・・表示部
１２・・・・・キー入力部
２１・・・・・ＥＦＭ復調回路
２３・・・・・ＰＬＬ・タイミング発生回路
２４・・・・・サブコードＱ処理回路
２５・・・・・誤り訂正処理回路
２６・・・・・デコード処理用ＲＡＭ
２７・・・・・読出／書込制御回路
２９・・・・・タイミング発生回路
３１、３３、３５・・・・・レジスタ
３６・・・・・データ比較器[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a disk reproducing apparatus that stores data read from a disk-shaped recording medium in a memory, reads the data from the memory at a constant rate, and reproduces the data.
[0002]
[Prior art]
Generally, in a tape recorder or a disc player for recording and / or reproducing a digital audio signal, a digital video signal, and the like, the recording digital signal includes digital audio data, digital video data, and the like that have been subjected to error correction coding processing and interleaving processing. Many data have main data and auxiliary data such as address information and control information. For example, in the format of a so-called compact disc (CD), stereo left and right two-channel audio signals are each sampled at 44.1 kHz and quantized by 16 bits to obtain an audio PCM signal. Encoding processing is performed as main data. This main data includes auxiliary information including information such as identification information of a song or between songs, a song number (track number), an elapsed time from the beginning of each song (lap time), an absolute time (absolute time), and emphasis control. Data, so-called subcode data, is added to form recording data, and the recording data is modulated by an EFM (8-14 modulation) method to form a recording signal.
[0003]
When a compact disc (CD) having such a format is reproduced by an ordinary reproducing apparatus, a clock component is generally detected (clock reproduced) from a EFM signal read from the disc using a PLL (phase locked loop) configuration. The reproduced clock fetches binary data, and demodulates the EFM signal. The data after the EFM demodulation is usually subjected to decoding (decoding) processing including error correction and deinterleaving based on the CIRC using a RAM for decoding processing to be converted into a digital audio signal (PCM signal). Data is written to the decode processing RAM in synchronization with the reproduction clock of the PLL system, and data is read in synchronization with a clock from a reference oscillator such as a crystal oscillator. The digital audio PCM signal obtained by the decoding process becomes an analog audio signal via a D / A converter and a low-pass filter (LPF).
[0004]
Incidentally, in a data reproducing apparatus, particularly an apparatus having an optical pickup such as the above-mentioned CD player or the like, a servo system such as a focus servo and a tracking servo of the optical pickup comes off due to mechanical disturbance such as shock or vibration to the device. In some cases, normal data reproduction cannot be performed. In this case, it is not possible to cope with the error correction as described above, and the reproduction may be temporarily interrupted.
[0005]
In view of this, the applicant of the present application first described in the specification and drawings of Japanese Patent Application No. 3-25566 that the reproduced data was stored in a relatively large-capacity buffer RAM and read out at a constant rate. By always storing a predetermined amount or more of reproduced data in the buffer RAM, even if normal data cannot be obtained from a medium such as a disk due to a reading error or the like, the data stored in the buffer RAM can be stored. And a system for reading the audio data and compensating for the interruption of the reproduction signal such as a sound interruption.
[0006]
As such a system, for example, in the case of a compact disk reproducing apparatus as described above, data is read out from a disk at high speed in a burst (intermittent) manner and sequentially written into the buffer RAM, and data is continuously read from the RAM. When reading data at a constant rate and writing data to the buffer RAM, it is necessary to control the write address and store adjacent data in the RAM in a continuous state. Specifically, for example, the disk is rotated at a rotation speed of about twice or three times to four times the standard, and the data read from the disk is divided into sub-coding frames (sub-code blocks, 13.3 msec during standard reproduction). (Length) in the buffer RAM.
[0007]
[Problems to be solved by the invention]
By the way, in a data reproducing apparatus using such a buffer RAM, for example, a CD player, between data read from a disk and a signal (music or the like) read from the buffer RAM and currently reproduced. Has a time difference at least corresponding to the data stored in the buffer RAM. The decoded main data (PCM data) itself includes auxiliary information such as the subcode data, that is, information such as a song number (track number), an absolute time, a time in a song (lap time), and de-emphasis. Etc. are not left. Therefore, when the sub-code data read from the disc is used to display the music number and time of the reproduced music or the like, a deviation from the actually reproduced music occurs due to the time difference, which causes an unnatural result. It will be displayed.
[0008]
It is conceivable that not only the main data but also the auxiliary data (subcode data and the like) is stored in the buffer RAM as it is, but the storage capacity of the main data is reduced accordingly, and the writing / reading process and the configuration are complicated. Is not preferred.
[0009]
To solve this problem, it is conceivable to obtain time information corresponding to the content currently being reproduced from the time information of the subcode data read from the disc. Although the elapsed time (lap time) is often displayed, if the song currently being played is different from the song being read from the disc, the current playback is performed using the lap time read from the disc. It is difficult to find the lap time of the middle song. Further, during special reproduction such as random reproduction or AB repeat, even during reproduction, writing to the buffer RAM is interrupted due to access to the disk, etc. If information or the like cannot be read, it is difficult to obtain time information that matches the content of the main data currently being reproduced.
[0010]
SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has been made in consideration of the above problem. In a disk reproducing apparatus that controls writing / reading of main data read and reproduced from a disk-shaped recording medium to / from a buffer memory, a buffer Time information having an accurate correspondence with the main data read out from the memory for recording can be obtained. In particular, the elapsed time (lap time) of each file (each song) can be obtained at the time of file switching or special reproduction. However, an object of the present invention is to provide a disk reproducing apparatus that can be accurately obtained.
[0011]
[Means for Solving the Problems]
A disk reproducing apparatus according to the present invention is a reproducing apparatus for reproducing a disk-shaped recording medium in which main data and an absolute time separated by a file unit are recorded, wherein the main data and the absolute time are reproduced from the disk-shaped recording medium. Reproducing means, a separating means for separating the main data reproduced by the reproducing means from the absolute time, a buffer memory for temporarily storing the main data separated by the separating means, and a buffer memory. Memory control means for intermittently recording main data separated by the separation means at a first speed and continuously reading the data at a second speed lower than the first speed; and writing the data to the buffer memory. The amount of delay is calculated based on the write address of the main data to be read and the read address to be read from the buffer memory. The above-mentioned problem is solved by having calculating means for calculating time information of main data read from the buffer memory based on the calculated delay amount and the absolute time separated by the separating means. I do.
Further, the disk reproducing apparatus according to the present invention is a reproducing apparatus for reproducing a disk-shaped recording medium in which main data divided in file units, an absolute time, and the elapsed time in file units are recorded. Reproducing means for reproducing the main data, the absolute time, and the elapsed time in file units from the main data, separating means for separating the main data, the absolute time, and the elapsed time in file units reproduced by the reproducing means, and the separating means And a buffer memory for temporarily storing the main data separated by, and intermittently recording the main data separated by the separating means in the buffer memory at a first speed, which is slower than the first speed. Memory control means for continuously reading at a second speed, and a write address of main data to be written to the buffer memory A delay amount is calculated based on a read address to be read from the buffer memory, and the buffer amount is calculated based on the calculated delay amount, the absolute time separated by the separating unit, and the elapsed time in file units. The above-described problem is solved by having a calculating unit that calculates time information of the main data read from the memory.
[0012]
That is, the absolute time information of the currently reproduced main data is obtained in accordance with the absolute time information from the auxiliary data and the time of the delay amount, and from the absolute time of the currently reproduced main data, the currently reproduced music (file ) Is subtracted from the absolute time at the head position to obtain the so-called lap time in the music (in the file).
[0013]
Here, the buffer memory has a ring-shaped address memory space, and the delay amount (time difference) is determined according to an address difference from a write address to a read address. The auxiliary data is, for example, subcode Q data in a so-called CD format. The subcode Q data includes absolute time (absolute time) information from the head position of the disc, elapsed time (lap time) information for each song, Time-related information such as number (track number) information and index number information, and control information such as emphasis information are included. The time information and the number information are displayed. Here, the time information such as the absolute time or the elapsed time in the music (lap time) is obtained by subtracting the delay time from the value of each time information obtained from the auxiliary data (subcode Q data). Can be.
[0014]
Further, an absolute time is used as time information obtained from the auxiliary data, an elapsed time in the file is calculated based on the absolute time and the absolute time at the head position of the file, and based on the elapsed time and the delay amount. It is preferable to calculate the elapsed time in the file currently being reproduced.
[0015]
Further, when continuously reproducing a plurality of files on the recording medium, the identification information of the old file is updated to the identification information of the new file at the boundary position of the file of the main data read from the buffer memory. Is preferred.
[0016]
[Action]
Based on the file identification information and the time information, the time information of the main data read from the buffer memory is calculated, and the elapsed time from the head position of the current file is calculated. The elapsed time in the file at the same timing as the main data read from the buffer memory and actually reproduced is obtained.
[0017]
【Example】
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing a schematic configuration of an apparatus in which a data reproducing apparatus according to the present invention is applied to a so-called compact disc (CD) player. That is, on the optical disk 1, so-called CD-format recording data is recorded. The so-called CD format will be briefly described. The upper and lower 8 bits of PCM digital audio data of 16 bits per word are separated into symbols which are error correction coding units, and are referred to as so-called CIRC (cross interleave). (Reed-Solomon code), an error correction parity is added, and an interleave process is performed. The main data of a total of 32 symbols of 24 symbols of the CIRC-encoded audio data and 8 symbols of parity constitutes one recording unit (frame), to which a so-called sub-code, which is 8-bit auxiliary data, is added. The frame is modulated by an 8-14 modulation method and a frame synchronization pattern is added, so that one frame is recorded on the optical disc 1 as an EFM signal of 588 channel bits. The sub-code is one block (sub-coding frame) of 98 frames, and carries auxiliary information for eight channels P to W. The Q channel of this subcode includes auxiliary data such as a song number, an index number, an elapsed time in the song, and an absolute time.
[0018]
In FIG. 1, the optical disk 1 is rotated by a drive motor 18 at a speed higher than a standard speed (linear speed) (for example, twice as fast), and a signal is read out intermittently or burst by an optical pickup 2 to preamplify. The signal is amplified at 3 and sent to the signal processing unit 4 as a so-called RF signal. This RF signal is a signal modulated by the above-described EFM method, and is subjected to processing such as EFM demodulation, deinterleaving, error correction, interpolation, and decoding of a subcode in the signal processing unit 4, and its main data ( The audio PCM data) output is stored in the buffer RAM 6 via the RAM controller 5. The data transfer rate up to this point is higher (eg, twice as high) than the standard reproduction rate in accordance with the high-speed disk rotation drive. However, the reading of data from the optical disk 1 is performed intermittently or in a so-called burst manner, and even if the instantaneous data transfer rate is higher than the standard, the average rate including the read pause period is almost the same as the standard reproduction. Rate. In this way, the data sent and stored intermittently or burstwise to the buffer RAM 6 is continuously read out by the RAM controller 5 at the standard reproduction rate, and the D / A converter 7 and the LPF (low-pass filter) are used. ) 8 to be extracted as an analog audio output signal.
[0019]
The servo control circuit 9 performs control operations such as focus servo, tracking servo, spindle motor servo, and thread (head movement) servo. That is, focus control of the optical system of the optical pickup 2 is performed by the focus servo so that the focus error signal becomes 0, and tracking control of the optical system of the optical pickup 2 is performed by the tracking servo so that the tracking signal becomes 0. Further, the rotation of the drive motor 18 is controlled by the spindle motor servo so that the optical disk 1 is driven to rotate at a predetermined linear velocity (for example, twice the standard linear velocity). Further, the sled servo controls the movement of the optical pickup 2 to a target track position of the optical disk 1 specified by the system controller 10. The servo control circuit 9 that performs such various control operations sends information indicating the operation state of each unit controlled by the servo control circuit 9 to the system controller 10.
[0020]
The system controller 10 includes a CPU (Central Processing Unit) such as a microprocessor for controlling the operation of each unit, a ROM (Read Only Memory) in which a control program executed by the CPU is stored in advance, and various types of data. A so-called microcontroller having a RAM (random access memory) that is read and temporarily stored, and an I / O (input / output) circuit for transmitting and receiving various signals between the CPU and the outside. It is a computer (microcomputer) system. The system controller 10 is connected to a display unit 11 for displaying an operation state of each unit, a key input operation unit 12 for instructing various operations, and the like. As the display unit 11, for example, an LCD (liquid crystal display), an LED (light emitting diode) display, an FL display, a plasma display, or the like is used. The key input operation unit 12 is provided with various operation keys such as a play button, a stop button, and a fast forward button. The system controller 10 sends and receives signals to and from the signal processing unit 4 and the RAM controller 5, and controls the operations of the signal processing unit 4 and the RAM controller 5.
[0021]
Here, for example, when a cause occurs that the servo system is disturbed by disturbance or the like and the reproduction signal is interrupted, that is, specifically, for example,
a) If the focus goes out,
b) When the subcode Q data becomes discontinuous,
c) If the PLL system becomes unstable for a certain period of time,
d) When the interpolation processing is performed (the interpolation flag is set),
For example, the system controller 10 monitors this and interrupts the writing to the buffer RAM 6. Then, after returning the servo system, for example, an address immediately before the interruption of the reproduction signal is accessed, and writing is restarted from the address position. As a result, as long as the data stored in the buffer RAM 6 does not become empty, continuous reproduction output can be obtained. Also, when the data stored in the buffer RAM 6 becomes full, the writing to the RAM 6 is temporarily interrupted, and a pause operation or the like is started.
[0022]
By the way, the RF signal input to the signal processing unit 4 is synchronized with a so-called PLL clock including the rotation unevenness of the optical disc 1, while the main data output to the RAM controller 5 is used as a reference clock. For example, since it is synchronized with a so-called crystal clock, jitter exists between the two. For this reason, if the timing at which the writing to the buffer RAM 6 is started is made dependent on the absolute time obtained by decoding the so-called subcode Q data in the signal processing unit 4, a connection error such as data loss or duplication occurs. I do. For this reason, a data comparison block is provided in the RAM controller 5 so that the data of the last few samples of the data written in the buffer RAM 6 and the data sent from the signal processing unit 4 to the RAM 6 via the RAM controller 5 are stored. And the data from the signal processing unit 4 is written to the buffer RAM 6 when the data match.
[0023]
That is, FIG. 2 shows a specific example of the signal processing unit 4, and FIG. 3 shows a specific example of the RAM controller 5.
2, the RF signal from the preamplifier 3 is sent to an EFM demodulation circuit 21, a synchronization detection circuit 22, and a PLL / timing generation circuit 23, respectively. The EFM demodulation circuit 21 demodulates the RF signal modulated by the EFM method, and sends the main data signal to the data bus DB and the subcode data signal to the subcode Q processing circuit 24. The synchronization detection circuit 22 detects the sub-coding frame synchronization signal and sends it to the PLL / timing generation circuit 23. The PLL / timing generation circuit 23 detects the channel bit clock (EFM clock) component of the RF signal, locks the PLL, and divides the channel bit clock by using the sub-coding frame synchronization signal. , A word clock, a bit clock of data after EFM demodulation, and the like, and send a write clock WCK to the read / write control circuit 27. Further, a sub-coding frame synchronization signal or the like is output from the PLL / timing generation circuit 23 and is used for, for example, a spindle servo. Subcode Q data and the like are serially output from the subcode Q processing circuit 24 and are used as current position information of the optical pickup 2 on the optical disk 1.
[0024]
The main data (audio data and parity data for error detection and correction) sent from the EFM demodulation circuit 21 to the data bus DB is written from the PLL / timing generation circuit 23 including a jitter component due to uneven rotation of the optical disc 1 or the like. The data is written to the decoding RAM 26 by the read / write control circuit 27 in synchronization with the write clock WCK. After that, while the read / write to / from the decoding RAM 26 is controlled by the read / write control circuit 27, error detection / correction processing and deinterleave processing by the error correction processing circuit 25 are performed based on the CIRC. . The decoding RAM 26 has such a capacity that a predetermined margin (for example, ± 24 frames) can be obtained for absorbing the jitter, in addition to the capacity required for the CIRC decoding (for example, about 108 frames). For example, a 32 kbit RAM is used. The decoded main data (PCM data) is read from the decoding RAM 26 by the read / write control circuit 27 in synchronization with a read clock RCK from a timing generation circuit 29 having a reference oscillator such as a crystal oscillator. And sent to the interface circuit 28. The interface circuit 28 outputs the decoded main data and various clocks such as a bit clock BCK, a word clock WDCK, and an LR (for switching between left and right stereo channel words) clock LRCK. The RAM controller 5 and the system controller 10 etc. Here, the write / read operation is performed intermittently at a speed higher than the standard, for example, twice as fast.
[0025]
Next, in FIG. 3, input data from (the interface circuit 28 of) the signal processing circuit 4 is sent to the register 31 and stored as 16-bit PCM data per sample, and the system controller 10 permits data writing. In this case, the data is written to the buffer RAM 6 via the data selector 32 in accordance with the write address output from the address generation circuit 34. At this time, data writing is performed intermittently at a speed higher than the standard. Data is read from the buffer RAM 6 via the data selector 32 into the register 33 in accordance with the read address output from the address generation circuit 34, and is read out at a constant reproduction rate according to the sampling frequency (for example, 44.1 kHz). The signal is continuously output from the D / A converter 33 and sent to the D / A converter 7.
[0026]
Here, when the writing to the buffer RAM 6 as described above is temporarily interrupted and then resumed, that is, when the data connection is performed, the address at the time when the data was last written into the buffer RAM 6 is determined by the address generation circuit 34. The data is output from the buffer RAM 6 to the register 35 via the data selector 32. This data is compared with the data input from the signal processing unit 4 to the register 31 by the data comparator 36, and when they match, a match output is issued to determine the timing of data connection. That is, the input data from the signal processing unit 4 after the coincidence output is obtained may be written into the buffer RAM 6.
[0027]
Next, FIG. 4 schematically shows a write / read operation for the buffer RAM 6 in a memory space, and FIG. 5 shows an example of an internal configuration of the address generation circuit 34. 4 and 5, when the write enable signal W-EN from the system controller 10 of FIG. 1 is sent to the write address counter 13, the write address counter 13 operates and the write address counter 13 becomes higher than the standard. Generate a write address WA which proceeds at a high speed (increments). The data is written to the buffer RAM 6 by the write address WA. Further, the system controller 10 or the like confirms a skip in sound by checking subcode information or the like, and sends a state good signal SOK to the valid write address latch 14 if there is no problem. Effective write address latch 14 latches write address WA from write address counter 13 in response to this signal SOK, and outputs it as effective write address VWA. The stored data up to the address VWA is reproducible data with no sound skip or the like, and can be sent to the D / A converter 7.
[0028]
Further, the read address counter 15 operates in response to the read enable signal R-EN from the system controller 10, generates a read address RA that advances at a standard speed, and sequentially reads the data written in the buffer RAM 6. Since the step speed (write speed) of the write address WA is higher than the speed (read speed) of the step operation (increment) of the read address RA, the address WA becomes the address RA in the loop memory space. In this case, the step operation of the write address WA is stopped, and the writing is resumed when the read address RA advances and the remaining amount of data falls below a predetermined amount (step of the write address WA). Resuming operation). The remaining data amount at this time indicates the amount of data that can be actually reproduced from the effective write address VWA to the read address RA. The subtracter 16 obtains an address difference ΔA obtained by subtracting the address RA from the address VWA.
[0029]
Here, the time between the data read from the buffer RAM 6 and sent to the D / A converter 7 and the time information of the subcode obtained by the subcode Q processing circuit 24 or the like and held by the system controller 10 is stored. The time difference is obtained by adding the delay amount in the decoding RAM 26 and the delay amount in the buffer RAM 6. The delay amount in the decoding RAM 26 is about tens of msec including the jitter correction described above. In the following description, only the amount of delay in the buffer RAM 6 is taken into consideration.
[0030]
Therefore, the time difference Td between the actual reproduced data and the time information of the subcode is obtained by dividing the data amount Dm according to the address difference ΔA (= VWA−RA) by the data read rate Dr. Assuming that the number of bits of a storage unit (word) for one address of the buffer RAM 6 is n bits, the time difference Td is
Td = Dm / Dr = (n × ΔA) / Dr (1)
It becomes.
[0031]
From the above, the system controller 10 delays all the subcode information received from the subcode Q processing circuit 24 or the like of the signal processing unit 4 by the time difference Td, and performs control operations such as actual time display and deemphasis switching. Should be performed. That is, the display unit 11 displays the absolute time T _ABS And the elapsed time (lap time) T in the song _LAP Is displayed, the absolute time T obtained from the subcode Q information is used. _QABS And time T in the song _QLAP The values obtained by subtracting the time differences Td from the above may be displayed. Also, when switching control such as de-emphasis is performed, the contents can be made to match the contents of the reproduced audio signal by switching with a delay of the time differences Td. The same applies to the display of the song number (track number) and the index number.
[0032]
Further, even in a special reproduction state such as a pause (pause) or a re-beat between A and B, by performing control while taking the time difference Td into consideration, an unnaturalness occurs between display of the apparatus, audio output, and key operation. You can avoid giving a feeling.
[0033]
For the address difference ΔA, it is not necessary to obtain all bits of the address bit number (for example, 20 bits), and it may be possible to use several higher-order bits depending on required accuracy. Here, as a specific example of the buffer RAM 6, the bit number n of one word is 4 bits and the bit number of the address is 20 bits (A ₀ ~ A ₁₉ ), A memory having a storage capacity of 4 Mbits is used. ₁₆ ~ A ₁₉ ) Alone, the accuracy can be distinguished in 0.25 Mbit units. When the data read rate Dr is about 1.4 Mbit / sec, a 20-bit address (A ₀ ~ A ₁₉ ) Upper 4 bits (A ₁₆ ~ A ₁₉ ), And the amount of time conversion [sec. Table 1 is shown in Table 1 below.
[0034]
[Table 1]

[0035]
However, in this case, an error occurs in the data after the calculation, and the time may be returned in the display of the elapsed time of the CD or the like. In such a case, an unnatural feeling can be prevented by using a program so that the calculated value is not reduced by the error.
[0036]
In addition, the address difference ΔA is displayed on the display unit 11 by a number or a visual expression so that the user of the device can be notified of the remaining amount of memory in the buffer RAM 6 and the amount of data stored in the memory. It is useful for checking the operation state. Here, the display that expresses the visual amount is, for example, a fixed display element that expresses a container reminiscent of the buffer RAM 6 and a reproduction that is arranged at a position surrounded by the fixed display element and stored in the RAM 6. It can be realized by a variable display element that expresses a possible data amount one by one.
[0037]
Next, the elapsed time from the start position of each song, so-called lap time T _LAP Will be described. This lap time T _LAP The time difference (delay amount) Td between writing and reading determined according to the amount Dm of data reproducible in the buffer RAM 6 is determined by the lap time T of the subcode Q data. _QLAP Can be calculated by subtracting from T _QLAP And T _LAP Wrap time T of the subcode Q data _QLAP Is not used directly, but the absolute time (absolute time) T of the subcode Q data _QABS Lap time T using the value obtained by subtracting the delay amount Td from _LAP Seeking.
[0038]
This lap time T _LAP Is roughly divided into three types of calculation methods. That is,
(A) When the track number (song number) of the subcode Q data and the track number of the song (file) read from the buffer RAM 6 and currently reproduced are the same.
(B) When the track number of the subcode Q data is different from the track number of the music being reproduced due to switching of music during normal reproduction.
[0039]
(C) When the track number of the subcode Q data is different from the track number of the music being reproduced during special reproduction such as shuffle or random reproduction, program reproduction, or AB repeat reproduction.
It is.
[0040]
Here, what can be said in any of the above cases (a) to (c) is a difference in display when the index number is “00” and when the index number is other than “00”. That is, the index number “00” is a silent portion before the beginning of the song, and a minus number is displayed so that “00:00” (0 minute 0 second) is at the beginning of the song. It is necessary to change the displayed numbers. When the song reaches the beginning of the song, the index number becomes "01", and a number that increases according to the elapsed time is displayed. This will be described with reference to FIG. 6. In the area of index number "00", the lap time T obtained from the sub-code Q data increases as the distance from the head position TOP of the music piece increases (to the left in the figure). _QLAP Is larger than “00”, and the value of seconds is also larger than 0 although not shown. Therefore, while reading the area of index “00” along the reproduction direction, the lap time T _QLAP Is detected as a value decreasing toward 0, and when it reaches the head position TOP of the song and enters the area of the index “01”, it is detected as a value increasing from 0.
[0041]
Also, the absolute time T in the time information _QABS And T _ABS Lap time T, which is the elapsed time from the beginning of the song TOP _QLAP And T _LAP In order to determine the lap time T, the top position TOP of the music, that is, the index number is "01" _QLAP Is a top position time (hereinafter referred to as a top time) T which is an absolute time at a position of “00: 00.00” (0 minute, 0 second, 0 frame). _TOP Is required. This top time T _TOP Is the absolute time T obtained from the subcode Q data _QABS And lap time T _QLAP By
For index number "00":
T _TOP = T _QABS + T _QLAP +00: 00.01 (2)
For index numbers other than "00":
T _TOP = T _QABS -T _QLAP ... (3)
Is calculated by the following equations. “00: 00.01” in the above equation (2) takes into account that the frame immediately before the top position TOP is “00” in the area of the index “00” in FIG. . Such a top time T _TOP Is calculated every time a song is changed, and saved in a memory or the like.
[0042]
Further, the delay amount (time difference between writing and reading) Td in the buffer RAM 6 and the absolute time T of the subcode Q data. _QABS From the absolute time T of the main data being reproduced _ABS To
T _ABS = T _QABS −Td (4)
It is calculated by the following equation. This currently playing absolute time T _ABS Is the top time T obtained by the above equations (2) and (3). _TOP Before or after. If it is before, it can be determined that the index number is "00", and if it is after, it can be determined that the index number is other than "00". Further, the absolute time T during reproduction obtained from the equation (4) _ABS And the above top time T _TOP And the end time T described later _END By comparing with the above, it is determined whether or not the currently reproduced position is within the same track (within the same music). Then, when in the same track, that is, in the case of the above (a), according to the index number of the position currently being reproduced,
For index numbers other than "00":
T _LAP = T _ABS -T _TOP ... (5)
For index number "00":
T _LAP = T _TOP -T _ABS ... (6)
Lap time T of the main data being reproduced _LAP Is calculated and displayed on the display unit 11.
[0043]
FIG. 7 is a diagram showing each time in the above case (a). The track number (song number) N of the subcode Q of the data read from the disk is shown in FIG. _SUBQ And the track number N of the main data read from the buffer RAM 6 and currently being reproduced. _PB Have the same value “01”. FIG. 8 shows the case of the above (b), that is, the track number N of the subcode Q data during normal reproduction. _SUBQ And the track number N of the song being played _PB Are different from each other. FIG. 9 shows the case of the above (c), that is, the track number N of the subcode Q data during the special reproduction. _SUBQ And the track number N of the song being played _PB Are different from each other. In these figures, for the sake of simplicity, the delay amount (time difference between writing and reading) Td is shown as being constant. However, in practice, high-speed intermittent writing and constant rate Td is dynamically changed by the reading in the step (d).
[0044]
In the case of the above (a) shown in FIG. 7, the relations of the above-described equations (4) to (6) apply as they are. In FIG. 7, index number I of subcode Q data _SUBQ At the boundary between “00” and “01”, that is, at the absolute time T _QABS Is the top time T _TOP And index number I _SUBQ Is other than "00" (when "01", "02", etc.), the absolute time T _QABS And lap time T _QLAP Is the difference between this top time T _TOP It has become. Absolute time T of main data being reproduced _ABS Is the absolute time T of the subcode Q according to the above equation (4). _QABS From the lap time T during reproduction. _LAP Is the absolute time T during the reproduction according to the above equation (5). _ABS From above top time T _TOP Is obtained by subtracting This lap time T _LAP Is displayed. The track number (song number) N being reproduced _PB And index number I _PB Are display values (display track number and display index number), respectively, and are displayed on the display unit 11 shown in FIG. The index number I of the main data currently being reproduced _PB Is “00”, the lap time T having a negative value is calculated by the above equation (6). _LAP Is displayed.
[0045]
Next, in the case of the above (b) shown in FIG. 8, while performing the display of the above (a), the track number (song number) N _QSUB The switching timing is constantly monitored. Subcode Q absolute time T immediately before this track is switched _QSUB Is the end time T _END And save it in a memory or the like. And the absolute time T during the reproduction _ABS Is this end time T _END Till the top time T of the previous track number "01" _TOP1 Is used to calculate the above equations (4) and (5) to obtain the lap time T. _LAP Is displayed, and the display track number (the track number N being reproduced) is displayed. _PB ) Etc. also hold the numerical value of the previous track. Absolute time T during playback _ABS Is the end time T _END Is reached, the top time T of the track number “02” obtained by the above equations (2) and (3) is reached. _TOP2 Lap time T using _LAP Is calculated and displayed. Also, the track number N of the main data being reproduced at this time. _PB And index number I _PB Are displayed on the display unit 11 or the like as display track numbers or display index numbers, respectively.
[0046]
Next, FIG. 9 shows the case of the above (c). There is a portion where the subcode Q data cannot be obtained due to the disk access operation. _QABS Are not continuous. Therefore, the flag (special reproduction flag) F that is turned on during the access operation _SP And the flag F _SP Is used to determine the time information and the like during reproduction. FIG. 9 shows an example in which a track having a track number of “01” is moved to a track of “05” in program reproduction or the like.
[0047]
In the case of FIG. 9, first, the end time T on the track “01” is set. _END Is detected and saved in a memory or the like. In the special reproduction access, since the position of “00: 00.00” (0 minute, 0 second, 0 frame) of the index “01” of the target track “05” is accessed, the area of the index “00” is reproduced. There is no need to display. In this case, the lap time T of the subcode Q is calculated from the delay amount (time difference) Td of the buffer RAM 6. _LAP Is subtracted, the remaining time of the current track (hereinafter referred to as rest time) T _REST Is required, and this rest time T _REST Becomes 0, it means that the main data being reproduced has moved to the next target track "05", and the flag F _SP Turn off. Therefore,
T _REST = Td-T _QLAP ... (6)
T _ABS = T _END -T _REST ... (7)
T _LAP = T _ABS -T _TOP ... (8)
Lap time T _LAP Is derived.
[0048]
As described above, since the absolute time (absolute time) is mainly considered, so-called remaining display can be performed without any problem. Note that an error of about 0.2 second may occur in an actual device due to a calculation error of the value of the delay amount Td, etc., and the lap time T calculated by the above-described calculation. _LAP May be smaller than the value previously determined. Therefore, it is preferable to compare the value obtained by the calculation with the previous calculated value and to adopt a method of adopting the larger one.
[0049]
FIGS. 10 and 11 show the lap times T in the above three cases. _LAP 11 is a flow chart for explaining the calculation procedure of FIG. 11, in which connectors A and B in FIG. 10 are connected to connectors A and B in FIG.
In FIGS. 10 and 11, in the first step S41, the delay amount (time difference) Td according to the above equation (1) is calculated and obtained. Next, proceeding to step S42, a special reproduction flag F indicating that the current mode is the special reproduction mode (that is, for example, shuffle or random reproduction, program reproduction, AB repeat reproduction, etc.). _SP It is determined whether or not is turned on. When not in the special playback mode (flag F _SP Is off) in cases other than the above (c), that is, in the above cases (a) and (b), and proceeds to the next step S43.
[0050]
In step S43, the absolute time T obtained from the subcode Q data _QABS The absolute time of the main data being reproduced is obtained by subtracting the delay amount Td from the above. _ABS Tentative absolute time T _Labs And This is because in the next step S44, the absolute time T obtained by the previous calculation is calculated. _ABS And the current calculated value (the above tentative absolute time) T _Labs And T _ABS More T _Labs Is large (T _ABS <T _Labs ), T is set in the next step S45. _Labs To T _ABS Otherwise, the absolute time T obtained last time _ABS Is used as it is, thereby avoiding a problem that the value of the displayed time is reduced. That is, YES (T _ABS <T _Labs ), The absolute time T is set in step S45. _ABS Are updated and the process proceeds to the next step S46, and if NO, the process directly proceeds to step S46.
[0051]
In step S46, the track number (song number) N of the subcode Q data from the disk _SUBQ Is the track number N of the main data currently being reproduced. _PB Then, if YES (same track number), the process proceeds to step S47. In step S47, the index number I being reproduced is _PB Is determined to be "00", and if NO, the process proceeds to step S48. In step S48, the index number I of the subcode Q _SUBQ Is "00" or not, and if NO, the process proceeds to step S49. In step S49, the track number N of the subcode Q _SUBQ The track number N currently playing _PB And the index number I being reproduced _PB Is “01”. This is because, in the case of a device that does not perform index display, all index numbers of “02” or more are treated as “01”. In the next step S50, the above equation (5) is calculated, and the lap time T _LAP Seeking. Thereafter, the process proceeds to step S51 to control emphasis and mute, and ends.
[0052]
When NO is determined in the above step S46, that is, when the track number N of the subcode Q is _SUBQ And the currently playing track number N _PB Is different, the process proceeds to step S52. In this step S52, the end time T _END And the absolute time T during playback _ABS And end time T _END Is T _ABS In the above case, the process proceeds to step S50, and the end time T _END Is T _ABS If it is smaller than the above, the process proceeds to the next step S53 and the top time T _TOP After performing the calculation of (1), the process proceeds to step S54. Also, if YES (I _PB = 00) or YES (I _SUBQ = 00) also proceeds to step S54. In this step S54, the top time T _TOP Is the absolute time T during playback _ABS It is determined whether or not it is below. If YES, the process proceeds to step S49, and if NO, the process proceeds to the next step S55. In step S55, the track number N of the subcode Q _SUBQ The track number N currently playing _PB And the index number I being reproduced _PB Is “00”. In the next step S56, the lap time T _LAP The process proceeds to step S57, and a flag F indicating that the main data of the index number “00” is currently being reproduced. ₀₀ Is turned on, the process proceeds to step S51.
[0053]
In the above step S42, YES (the special reproduction flag F _SP Is ON), the process proceeds to step S61 in FIG. 11, and the delay amount Td of the buffer RAM 6 is set to the lap time T of the subcode Q data. _QRAP It is determined whether or not: If NO, the process proceeds to the next step S62, where the rest time T _REST , Ie, Td-T _QLAP Is calculated, and then the process proceeds to step S63, where the tentative absolute time T similar to step S43 described above is calculated. _Labs Is calculated. The following steps S64 and S65 are the same as the above-described steps S44 and S45, and the steps S63 to S65 avoid a problem that the value of the displayed time decreases. In the next step S66, T _ABS -T _TOP Lap time T _LAP And the process proceeds to step S51 in FIG. YES in the above step S61 (Td ≦ T _QRAP ), The routine proceeds to step S67, where the special reproduction flag F _SP Is turned off, and the track number N of the subcode Q is _SUBQ The track number N currently playing _PB And the index number I being reproduced _PB Is “01”. In the next step S69, the lap time T _LAP After that, “00: 00.00”, that is, 0 minutes, 0 seconds, and 0 frames are inserted, the process proceeds to step S51 in FIG.
[0054]
As is clear from the above description, according to the present embodiment, it is only necessary to store the main data in the memory (buffer RAM 6), the memory capacity can be used effectively, and the read main data can be stored using the information of the write data. And control the data. Also, the absolute time T based on the subcode Q data _QABS And elapsed time in the song (lap time) T _QLAP By subtracting the time Td of the amount of delay in the buffer RAM 6 from the above, the time information (T _ABS And T _LAP ) Can be obtained, an appropriate display can be performed, and the amount of reproducible data in the buffer RAM 6 can be displayed to inform the operating state of the apparatus. In addition, it is possible to control reproduction data such as de-emphasis switching at a correct timing. Furthermore, when displaying the so-called lap time, which is the elapsed time in the music, the track being reproduced is different from the track of the subcode Q data, and even when in the special reproduction mode, it matches the content of the main data being reproduced. The calculated lap time can be obtained by calculation, and lap time display without error can be performed.
[0055]
The present invention is not limited to only the above-described embodiment. For example, as a recording medium, in addition to an optical disk, a magneto-optical disk, a magnetic disk, a magnetic tape, or the like can be used. Not limited. In addition to the PCM audio data, video data, compressed data, and the like can also be used as the main data. Further, the auxiliary data is not limited to the above subcode data, and can be applied to a format in which error correction processing is not performed. Of course, the hardware configuration is not limited to the illustrated example.
[0056]
As is apparent from the above description, according to the disk reproducing apparatus of the present invention, in the reproducing apparatus for reproducing the disk-shaped recording medium on which the main data separated in file units and the absolute time are recorded, Reproducing means for reproducing the main data and the absolute time from the shape recording medium; separating means for separating the main data and the absolute time reproduced by the reproducing means; and temporarily separating the main data separated by the separating means. The buffer memory for storing and the main data separated by the separating means in the buffer memory are intermittently recorded at a first speed and continuously read at a second speed lower than the first speed. Memory control means, a write address of main data to be written to the buffer memory, and a read address from the buffer memory; Calculating means for calculating a delay amount based on the read address and calculating time information of main data read from the buffer memory based on the calculated delay amount and the absolute time separated by the separating means; Therefore, it is possible to obtain time information and the like having an accurate correspondence with the main data read from the buffer memory.
Further, according to the disk reproducing apparatus of the present invention, in the reproducing apparatus for reproducing the disk-shaped recording medium in which the main data divided in file units, the absolute time, and the elapsed time in the file unit are recorded, Reproducing means for reproducing the main data, the absolute time, and the elapsed time in file units from a recording medium; separating means for separating the main data, the absolute time, and the elapsed time in file units reproduced by the reproducing means; A buffer memory for temporarily storing the main data separated by the separation means, and intermittently recording the main data separated by the separation means in the buffer memory at a first speed; A memory control means for continuously reading at a lower second speed; and a memory for writing main data to be written to the buffer memory. And a delay amount is calculated based on the read address to be read from the buffer memory, and the delay amount is calculated based on the calculated delay amount, the absolute time separated by the separation means, and the elapsed time in file units. It has a calculating means for calculating time information of main data read from the buffer memory, so that the elapsed time (lap time) of each file (each song) can be calculated especially at the time of file switching, special reproduction, etc. But it can be determined exactly.
[0057]
In particular, the absolute time information of the currently reproduced main data is obtained in accordance with the absolute time information from the auxiliary data and the time of the delay amount, and the currently reproduced music (file ) Can be easily and accurately obtained by subtracting from the absolute time at the start position of the song, that is, the elapsed time in the music (in the file), that is, the lap time.
[0058]
Further, when continuously reproducing a plurality of files on the recording medium, the identification information of the old file is updated to the identification information of the new file at the boundary position of the file of the main data read from the buffer memory. Thereby, the file identification information (song number) can be displayed in accordance with the main data being reproduced.
[0059]
Further, since the main data to which the auxiliary data is added is read from the recording medium to separate the main data, and the writing / reading of the buffer memory is controlled, the main data is not stored in the buffer memory. It is sufficient to store only data, and the effective utilization rate of the storage capacity can be increased.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an overall schematic configuration of an embodiment of a disk reproducing apparatus according to the present invention.
FIG. 2 is a block circuit diagram showing a specific example of a signal processing unit in the embodiment.
FIG. 3 is a block circuit diagram showing a specific example of a RAM controller in the embodiment and its periphery.
FIG. 4 is a diagram for explaining movement of a write address and a read address in a memory space of a buffer RAM in the embodiment.
FIG. 5 is a block diagram showing an example of an internal configuration of an address generation circuit in FIG. 3;
FIG. 6 is a diagram for explaining a relationship between an index number and a frame.
FIG. 7 is a diagram showing time information when the track number of the subcode Q data and the track number being reproduced are the same.
FIG. 8 is a diagram showing time information when a track number of subcode Q data is different from a track number being reproduced during normal reproduction.
FIG. 9 is a diagram illustrating time information when a track number of subcode Q data is different from a track number being reproduced during special reproduction.
FIG. 10 is a flowchart for explaining the operation of the embodiment.
FIG. 11 is a flowchart for explaining the operation of the embodiment.
[Explanation of symbols]
1 ... Optical disk
2 .... optical pickup
4 ... Signal processing unit
5 RAM controller
6 RAM for buffer
9 ... Servo control circuit
10. System controller
11 Display unit
12 ... Key input section
21 ... EFM demodulation circuit
23 PLL PLL / timing generation circuit
24 ... Sub-code Q processing circuit
25 ... Error correction processing circuit
26 ........ RAM for decoding processing
27 ... Read / write control circuit
29 ... Timing generation circuit
31, 33, 35 ... Register
36 ... Data comparator

Claims (5)

In a reproducing apparatus for reproducing a disk-shaped recording medium on which main data and absolute time separated in file units are recorded,
Reproducing means for reproducing the main data and the absolute time from the disk-shaped recording medium;
Separating means for separating absolute time from the main data reproduced by the reproducing means;
A buffer memory for temporarily storing the main data separated by the separating means,
Memory control means for intermittently recording the main data separated by the separation means in the buffer memory at a first speed and continuously reading out the main data at a second speed lower than the first speed;
A delay amount is calculated based on a write address of main data to be written to the buffer memory and a read address to be read from the buffer memory, and is separated from the calculated delay amount by the separation means. And a calculating means for calculating time information of the main data read from the buffer memory based on the absolute time thus obtained. 2. The disc reproducing apparatus according to claim 1, further comprising: display means for displaying time information corresponding to the main data read from said buffer memory calculated by said calculation means. In a reproducing apparatus for reproducing a disk-shaped recording medium in which main data separated in file units, absolute time, and elapsed time in file units are recorded,
Reproducing means for reproducing the main data, the absolute time, and the elapsed time in file units from the disk-shaped recording medium;
Separating means for separating the main data reproduced by the reproducing means, the absolute time, and the elapsed time in file units ;
A buffer memory for temporarily storing the main data separated by the separating means,
Memory control means for intermittently recording the main data separated by the separation means in the buffer memory at a first speed and continuously reading out the main data at a second speed lower than the first speed;
A delay amount is calculated based on a write address of main data to be written to the buffer memory and a read address to be read from the buffer memory, and is separated from the calculated delay amount by the separation means. A disk reproducing apparatus comprising: a calculating unit configured to calculate time information of main data read from the buffer memory based on the absolute time and the elapsed time in file units. 4. The disk reproducing apparatus according to claim 3, further comprising: display means for displaying time information corresponding to the main data read from said buffer memory calculated by said calculation means. 4. The disk reproducing apparatus according to claim 3, wherein the elapsed time in file units is composed of an elapsed time that gradually decreases during a silent period at a file head and an elapsed time that gradually increases during a sound period. .

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