JPH0685607A - High band component restoring device - Google Patents
High band component restoring deviceInfo
- Publication number
- JPH0685607A JPH0685607A JP23120592A JP23120592A JPH0685607A JP H0685607 A JPH0685607 A JP H0685607A JP 23120592 A JP23120592 A JP 23120592A JP 23120592 A JP23120592 A JP 23120592A JP H0685607 A JPH0685607 A JP H0685607A
- Authority
- JP
- Japan
- Prior art keywords
- audio signal
- original audio
- component
- frequency
- band
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- Signal Processing For Digital Recording And Reproducing (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は高域成分復元装置に係
り、特に原オーディオ信号が帯域制限されているために
欠落した成分を復元することで音質向上を図った高域成
分復元装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high frequency band component restoration device, and more particularly to a high frequency band component restoration device for improving sound quality by restoring a component missing due to band limitation of an original audio signal.
【０００２】[0002]
【従来の技術】コンパクトディスク、ＤＡＴ等のディジ
タルオーディオでは、サンプリング周波数ｆｓに対し、
ｆｓ／２以上の原オーディオ信号成分が存在すると所謂
折り返し雑音が生じるので、原オーディオ信号は帯域が
ｆｓ／２以下に制限されてディジタル記録されている。
コンパクトディスクではｆｓ＝44.1kHz の１種類、ＤＡ
Ｔではｆｓ＝48kHz ，44kHz 等の複数種類となっている
が、いずれにしても、ディジタルオーディオ信号をサン
プリング周波数ｆｓのままＤ／ＡコンバータでＤ／Ａ変
換すると、Ｄ／Ａコンバータ出力がパルス幅を持つこと
から、ｆ特の高域レスポンスが低下したり（アパーチャ
効果）、また、サンプリング周波数ｆｓが低いことで量
子化雑音が目立ったりする。このため、通常は、ディジ
タルオーディオ信号をＤ／Ａ変換する前に、ディジタル
フィルタを通してサンプリング周波数を、４倍、８倍等
のｎ倍に上げるオーバーサンプリングを行い、ｎｆｓの
サンプリング周波数でＤ／Ａ変換し、高域レスポンスの
低下を回避したり、量子化雑音を低減したりする処理が
なされている。2. Description of the Related Art In digital audio such as compact discs and DAT, the sampling frequency fs is
The presence of the original audio signal component of fs / 2 or more causes so-called aliasing noise, so that the band of the original audio signal is digitally recorded with the band limited to fs / 2 or less.
For compact discs, one type of fs = 44.1kHz, DA
In T, there are multiple types such as fs = 48kHz, 44kHz, etc. In any case, if the digital audio signal is D / A converted by the D / A converter with the sampling frequency fs, the D / A converter output has a pulse width. Therefore, the high frequency response of f characteristic is lowered (aperture effect), and the quantization noise is conspicuous due to the low sampling frequency fs. Therefore, normally, before D / A conversion of a digital audio signal, oversampling is performed through a digital filter to raise the sampling frequency to n times such as 4 times or 8 times, and the D / A conversion is performed at a sampling frequency of nfs. However, processing for avoiding a decrease in high-frequency response or reducing quantization noise is performed.
【０００３】[0003]
【発明が解決しようとする課題】ところで、オーディオ
信号は、単一周波数の純音成分だけから成る場合は少な
く、通常は基音と倍音の組み合わせから成る音色成分が
１又は複数含まれている。しかしながら、図４に示す如
く、原ディジタルオーディオ信号の帯域がｆｓ／２以下
に制限されていることにより、基音ｆ1 と倍音ｆ2 〜ｆ
4 の組み合わせから成る音色成分では、ｆｓ／２以上の
倍音ｆ3 ，ｆ4 の成分が欠落しており、ディジタルフィ
ルタでｎ倍オーバーサンプリングしたからといって、欠
落した倍音成分は復元しない。よって、基音と倍音の組
み合わせから成る音色成分については、生の音楽を忠実
に再現した再生ができないという問題があった。以上か
ら、本発明の目的は、原オーディオ信号で欠落している
高域成分を復元できるようにした高域成分復元装置を提
供することである。By the way, an audio signal is rarely composed of a pure tone component of a single frequency, and usually contains one or a plurality of tone color components composed of a combination of a fundamental tone and an overtone. However, as shown in FIG. 4, since the band of the original digital audio signal is limited to fs / 2 or less, the fundamental tone f 1 and the overtones f 2 to f 2
The tonal components comprising a combination of 4, fs / 2 or more harmonic f 3, components f 4 are missing, just because the n-times oversampling digital filter, missing harmonics is not restored. Therefore, there is a problem in that the tone color component composed of the combination of the fundamental tone and the overtone cannot be reproduced faithfully reproducing the live music. From the above, an object of the present invention is to provide a high-frequency component restoration device capable of restoring high-frequency components missing in the original audio signal.
【０００４】[0004]
【課題を解決するための手段】上記課題は本発明におい
ては、原オーディオ信号に対し周波数分析を行う周波数
分析手段と、周波数分析手段での分析結果から原オーデ
ィオ信号帯域中に基音と倍音が組で存在する音色成分を
抽出する抽出手段と、抽出手段で抽出された音色成分を
用いて、原オーディオ信号帯域より高域側の倍音成分を
予測し原オーディオ信号に外挿する外挿手段を備えたこ
とにより達成される。SUMMARY OF THE INVENTION In the present invention, the above-mentioned problem is solved by a frequency analysis means for performing frequency analysis on an original audio signal, and a combination of a fundamental tone and an overtone in the original audio signal band based on the analysis result of the frequency analysis means. And an extrapolation means for extrapolating to the original audio signal by predicting a harmonic component higher than the original audio signal band using the timbre component extracted by the extracting means. Will be achieved.
【０００５】[0005]
【作用】本発明によれば、原オーディオ信号に対し周波
数分析を行い、分析結果から原オーディオ信号帯域中に
基音と倍音が組で存在する音色成分を抽出し、抽出した
音色成分を用いて、原オーディオ信号帯域より高域側の
倍音成分を予測し原オーディオ信号に外挿する。これに
より、原オーディオ信号で欠落した倍音成分を復元し、
生の音楽を忠実に再現した再生が可能となる。According to the present invention, frequency analysis is performed on an original audio signal, a tone color component having a fundamental tone and a harmonic overtone in the original audio signal band is extracted from the analysis result, and the extracted tone color component is used. The overtone component on the high frequency side of the original audio signal band is predicted and extrapolated to the original audio signal. This restores the overtone component that was missing in the original audio signal,
Playback that faithfully reproduces live music becomes possible.
【０００６】[0006]
【実施例】図１は本発明の実施例構成図である。図中、
１０は音楽信号がディジタル記録されたコンパクトディ
スク、１２はコンパクトディスクの記録信号を読み取
り、１６ビット長でサンプリング周波数ｆｓ（＝44.1kH
z ）のディジタルオーディオ信号（原オーディオ信号）
ＤＳ0 を出力するディク読み取り部である。ディジタル
オーディオ信号ＤＳ0 は折り返し歪みの発生を防ぐため
帯域がｆｓ／２以下に制限されている。１４はディスク
読み取り部から出力された原ディジタルオーディオ信号
に対し、ｎ倍のオーバーサンプリングを行い高域レスポ
ンスの改善を行うディジタルフィルタである。ディジタ
ルフィルタは、１６ビット長の高精度でディジタルオー
ディオ信号ＤＳ1 を出力する。1 is a block diagram of an embodiment of the present invention. In the figure,
10 is a compact disc on which a music signal is digitally recorded, 12 is a signal recorded on the compact disc, and the sampling frequency fs is 16 bits (= 44.1 kH).
z) digital audio signal (original audio signal)
This is a disk reader that outputs DS 0 . The band of the digital audio signal DS 0 is limited to fs / 2 or less in order to prevent the occurrence of aliasing distortion. Reference numeral 14 is a digital filter for improving the high frequency response by oversampling the original digital audio signal output from the disc reading section by n times. The digital filter outputs the digital audio signal DS 1 with a high precision of 16 bits.
【０００７】１６はディジタルオーディオ信号ＤＳ0 に
対し周波数分析を行う周波数分析部であり、該周波数分
析部はＦＦＴ処理でディジタルオーディオ信号ＤＳ0 に
対し時間軸−周波数軸変換を行ってリアルタイムに周波
数分析を行う。１８は周波数分析部１６での分析結果よ
り、ディジタルオーディオ信号帯域内（ｆｓ／２以下)
に、基音と倍音の組み合わせから成る音色成分を抽出す
る抽出部、２０は抽出部で抽出された音色成分から所定
の予測関数を用いて、該音色成分が本来ｆｓ／２〜ｎｆ
ｓ／２の帯域で有しているべき倍音を予測し、該予測し
た倍音をｎｆｓのサンプリング周波数による１４ビット
長のディジタルオーディオ信号ＤＳ2 （時間軸上デー
タ）として出力する予測部である。Reference numeral 16 is a frequency analysis section for performing frequency analysis on the digital audio signal DS 0 , and the frequency analysis section performs time-frequency-axis conversion on the digital audio signal DS 0 by FFT processing to analyze the frequency in real time. I do. 18 is within the digital audio signal band (fs / 2 or less) according to the analysis result of the frequency analysis unit 16.
An extraction unit for extracting a tone color component composed of a combination of a fundamental tone and an overtone, and 20 using a predetermined prediction function from the tone color component extracted by the extraction unit so that the tone color component is originally fs / 2 to nf.
This is a prediction unit that predicts a harmonic overtone that should be included in the band of s / 2, and outputs the predicted harmonic overtone as a 14-bit digital audio signal DS 2 (time-axis data) having a sampling frequency of nfs.
【０００８】予測部２０は、抽出部１８で抽出された各
音色成分につき、基音と倍音の周波数関係及びレベル関
係から、予測関数を用いて、ｆｓ／２〜ｎｆｓ／２の帯
域に存在すべき倍音の周波数とレベルを予測計算する。
予測関数は、例えば、抽出部１８で抽出された或る１つ
の音色成分が図２（１）に示す如く、ｆ1 の基音、ｆ2
〜ｆ4 の倍音となっていたとき、ｆｓ／２に近い方の２
つの倍音ｆ3 ，ｆ4 のレベルを結んだ直線を予測関数Ｆ
とし、 ｆi ＝ｆ4 ＋（ｉ−４）・（ｆ4 −ｆ3 ） 但し、ｉ＝５、６、７、・・・・、 ｆｓ／２＜ｆi ＜ｎｆｓ／２ となる各ｆ5 、ｆ6 、・・・を予測倍音の周波数、
ｆ5 、ｆ6 、・・・での直線Ｆ上のレベルを予測倍音の
レベルとする。そして、予測部２０は各予測倍音につ
き、時間軸上での合成波形に係るディジタルオーディオ
信号を出力する。抽出部１８で抽出した音色成分が複数
個存在するときは、各音色成分毎に、倍音の予測を行
い、全て合成した波形に係るディジタルオーディオ信号
を出力する。The predicting unit 20 should exist in the band of fs / 2 to nfs / 2 by using a predictive function for each tone color component extracted by the extracting unit 18 from the frequency relationship and the level relationship between the fundamental tone and the overtone. Predictive calculation of harmonic overtone frequency and level.
Prediction function, for example, one certain tonal components extracted by the extraction unit 18 as shown in FIG. 2 (1), the f 1 fundamental, f 2
~ When it is a harmonic overtone of f 4 , 2 of the closer to fs / 2
Prediction function F is a straight line connecting the levels of the three overtones f 3 and f 4.
And f i = f 4 + (i−4) · (f 4 −f 3 ), where i = 5, 6, 7, ..., Fs / 2 <f i <nfs / 2 5 , f 6 , ... are frequencies of predicted overtones,
The level on the straight line F at f 5 , f 6 , ... Is the predicted overtone level. Then, the prediction unit 20 outputs a digital audio signal related to the synthesized waveform on the time axis for each predicted overtone. When there are a plurality of tone color components extracted by the extraction unit 18, overtone prediction is performed for each tone color component, and a digital audio signal related to all synthesized waveforms is output.
【０００９】なお、或る１つの音色成分について、Ｆの
傾きが例えば、−６dB/octより小さいとき、ｆｓ／２〜
ｎｆｓ／２の範囲の倍音は存在しないとしてもよい。ま
た、図２（２）に示す如く、抽出部１８で抽出された或
る１つの音色成分がｆ1 の基音、ｆ2 の倍音となってい
たとき、基音ｆ1 と倍音ｆ2 のレベルを結んだ直線を予
測関数Ｆとし、 ｆi ＝ｆ2 ＋（ｉ−２）・（ｆ2 −ｆ1 ） 但し、ｉ＝３、４、５、・・・・、 ｆｓ／２＜ｆi ＜ｎｆｓ／２ となる各ｆ3 、ｆ4 、・・・を予測倍音の周波数、
ｆ3 、ｆ4 、・・・での直線Ｆ上のレベルを予測倍音の
レベルとする。For a certain timbre component, if the slope of F is, for example, less than -6 dB / oct, fs / 2 to fs / 2
There may be no overtones in the nfs / 2 range. Further, as shown in FIG. 2 (2), the extraction unit 18 with the extracted one certain tonal components is f 1 fundamental, when it the harmonics f 2, the level of the fundamental tone f 1 and harmonic f 2 a straight line that connects the prediction function F, f i = f 2 + (i-2) · (f 2 -f 1) However, i = 3,4,5, ····, fs / 2 <f i < The frequencies of the predicted overtones are f 3 , f 4 , ...
The level on the straight line F at f 3 , f 4 , ... Is the predicted overtone level.
【００１０】２２はディジタルフィルタから出力された
ディジタルオーディオ信号ＤＳ1 をＤ／Ａ変換する１６
ビット長のＤ／Ａコンバータであり、ディジタルオーデ
ィオ信号ＤＳ1 がｎ倍オーバーサンプリングされている
ことから、ｆｓ／２付近の高域レスポンスが改善され、
量子化雑音の少ないｆｓ／２以下のアナログオーディオ
信号ＡＳ1 を出力する。２４は予測部２０から出力され
たディジタルオーディオ信号ＤＳ2 をＤ／Ａ変換する１
４ビット長のＤ／Ａコンバータであり、ｆｓ／２〜ｎｆ
ｓの帯域に入る倍音のアナログオーディオ信号ＡＳ2 を
出力する。２６は加算器であり、アナログオーディオ信
号ＡＳ1 とＡＳ2 を加算して、アナログオーディオ信号
ＡＳ3 として出力する。２８はカットオフ周波数ｆc が
ｎｆｓ／２のＬＰＦであり、アナログオーディオ信号Ａ
Ｓ3 に含まれるｎｆｓ／２以上の折り返し歪み成分をカ
ットする。予測部２０、Ｄ／Ａコンバータ２２と２４、
加算器２６により、高域倍音成分外挿手段３０が構成さ
れている。なお、周波数分析部１６、抽出部１８、予測
部２０はマイクロコンピュータやＤＳＰ（ディジタルシ
グナルプロセッサ）を用いて実現することができる。Reference numeral 22 denotes a D / A converter for the digital audio signal DS 1 output from the digital filter 16
It is a bit-length D / A converter, and since the digital audio signal DS 1 is oversampled n times, the high frequency response near fs / 2 is improved,
An analog audio signal AS 1 of fs / 2 or less with little quantization noise is output. Reference numeral 24 is a D / A converter for the digital audio signal DS 2 output from the prediction unit 20.
A 4-bit D / A converter, fs / 2 to nf
It outputs an overtone analog audio signal AS 2 in the s band. An adder 26 adds the analog audio signals AS 1 and AS 2 and outputs the result as an analog audio signal AS 3 . 28 is an LPF having a cut-off frequency f c of nfs / 2, and is an analog audio signal A
The aliasing distortion component of nfs / 2 or more contained in S 3 is cut. Predictor 20, D / A converters 22 and 24,
The adder 26 constitutes a high-frequency overtone component extrapolating means 30. The frequency analysis unit 16, the extraction unit 18, and the prediction unit 20 can be realized by using a microcomputer or DSP (digital signal processor).
【００１１】次に上記した実施例の動作を、ｎ＝４とし
た場合について簡単に説明する。ディスク読み取り部１
２でコンパクトディスク１０から読み取られたディジタ
ルオーディオ信号ＤＳ0 は、サンプリング周波数ｆｓ＝
44.1kHz で、帯域がｆｓ／２以下に制限されている。デ
ィジタルオーディオ信号ＤＳ0 はディジタルフィルタ１
４で４倍のオーバーサンプリングがなされ、サンプリン
グ周波数４ｆｓのディジタルオーディオ信号ＤＳ1 に変
換されたのち、Ｄ／Ａコンバータ２２でＤ／Ａ変換され
てアナログオーディオ信号ＡＳ1 として出力される。こ
のアナログオーディオ信号ＡＳ1 は、ｆｓ／２以下の原
オーディオ信号につき、ディジタルフィルタ１４のオー
バーサンプリングにより、アパーチャ効果によるｆｓ／
２近くのレスポンス低下の回避と量子化雑音の低減が図
られたものとなる。Next, the operation of the above-mentioned embodiment will be briefly described when n = 4. Disk reading unit 1
The digital audio signal DS 0 read from the compact disc 10 at 2 has a sampling frequency fs =
At 44.1kHz, the band is limited to fs / 2 or less. Digital audio signal DS 0 is digital filter 1
The signal is oversampled four times at 4, converted into a digital audio signal DS 1 having a sampling frequency of 4fs, and then D / A converted at a D / A converter 22 and output as an analog audio signal AS 1 . This analog audio signal AS 1 is an original audio signal of fs / 2 or less and is fs / due to the aperture effect due to the oversampling of the digital filter 14.
The reduction of the response near 2 and the reduction of the quantization noise are achieved.
【００１２】一方、ディジタルーオーディオ信号ＤＳ0
は、周波数分析部１６で周波数分析されたのち、抽出部
１８でｆｓ／２以下の帯域に存在する基音と１又は複数
の倍音の組み合わせからなる１又は複数の音色成分が抽
出される。そして、抽出部１８で抽出した各音色成分毎
に、予測部２０でｆｓ／２〜２ｆｓの帯域に存在すべき
倍音が予測され、予測した倍音全てが合成された時間軸
上でのディジタルオーディオ信号ＤＳ2 がサンプリング
周波数４ｆｓで出力される。ディジタルオーディオ信号
ＤＳ2 はＤ／Ａコンバータ２４でＤ／Ａ変換されてアナ
ログオーディオ信号ＡＳ2 として出力され、加算器２６
で帯域ｆｓ／２以下のアナログオーディオ信号ＡＳ1 と
合成されてアナログオーディオ信号ＡＳ3 として出力さ
れる。よって、アナログオーディオ信号ＡＳ3 は、図３
に示す如く、ｆｓ／２以下の帯域にアパーチャ効果が改
善され、かつ、量子化歪みが軽減された原オーディオ信
号成分（ＳＡ1 ）を含み、ｆｓ／２〜２ｆｓの帯域に、
本来、存在すべき倍音成分が外挿された信号成分（ＳＡ
2 ）を含むものとなる。アナログオーディオ信号ＡＳ3
はＬＰＦ２８で２ｆｓ以上の折り返し歪み成分が除去さ
れた後、外部出力される。On the other hand, the digital audio signal DS 0
Is subjected to frequency analysis by the frequency analyzing unit 16, and then the extracting unit 18 extracts one or a plurality of timbre components that are a combination of a fundamental tone and one or a plurality of overtones existing in a band of fs / 2 or less. Then, for each timbre component extracted by the extraction unit 18, the prediction unit 20 predicts overtones that should exist in the band of fs / 2 to 2fs, and a digital audio signal on the time axis in which all the predicted overtones are combined. DS 2 is output at a sampling frequency of 4fs. The digital audio signal DS 2 is D / A converted by the D / A converter 24 and output as the analog audio signal AS 2 , and the adder 26
Is combined with an analog audio signal AS 1 having a band of fs / 2 or less and output as an analog audio signal AS 3 . Therefore, the analog audio signal AS 3 is shown in FIG.
As shown in, the original audio signal component (SA 1 ) whose aperture effect is improved and the quantization distortion is reduced is included in the band of fs / 2 or less, and the band of fs / 2 to 2fs is
Originally, a signal component (SA
2 ) is included. Analog audio signal AS 3
After the aliasing distortion component of 2 fs or more is removed by the LPF 28, is output to the outside.
【００１３】この実施例によれば、原オーディオ信号で
はカットされていた高域の倍音成分を復元して、生の音
楽に忠実な音楽再生が可能となる。そして、原オーディ
オ信号に純音（単一周波数のサイン波）として含まれて
いる音色成分については、倍音の外挿はなされないの
で、原オーディオ帯域でのＴＨＤが悪化したり、再生音
に歪みが生じたりすることはない。According to this embodiment, it is possible to reproduce the high-frequency overtone component that was cut in the original audio signal and reproduce the music faithfully to the live music. Since the overtone is not extrapolated with respect to the timbre component contained in the original audio signal as a pure tone (single frequency sine wave), THD in the original audio band is deteriorated and the reproduced sound is distorted. It does not happen.
【００１４】なお、上記した実施例では、アナログ領域
でｆｓ／２以下の原オーディオ信号に対しｆｓ／２〜ｎ
ｆｓの予測倍音を外挿するようにしたが、ディジタル領
域で行うようにしてもよい。また、ｆｓは44.1kHz に限
られず、これ以上又はこれ以下であってもよく、更に、
ｎも２、８、１６等であってもよい。以上、本発明を実
施例、変形例等により説明したが、本発明は請求の範囲
に記載した本発明の主旨に従い種々の変形が可能であ
り、本発明はこれらを排除するものではない。In the above embodiment, fs / 2 to n are applied to the original audio signal of fs / 2 or less in the analog domain.
Although the predicted overtone of fs is extrapolated, it may be performed in the digital domain. Also, fs is not limited to 44.1 kHz, and may be higher or lower than this.
n may also be 2, 8, 16 or the like. Although the present invention has been described above with reference to the embodiments and modifications, the present invention can be modified in various ways according to the gist of the present invention described in the claims, and the present invention does not exclude these.
【００１５】[0015]
【発明の効果】以上本発明によれば、原オーディオ信号
に対し周波数分析を行う周波数分析手段と、周波数分析
手段での分析結果から原オーディオ信号帯域中に基音と
倍音が組で存在する音色成分を抽出する抽出手段と、抽
出手段で抽出された音色成分を用いて、原オーディオ信
号帯域より高域側の倍音成分を原オーディオ信号に外挿
する外挿手段を備え、原オーディオ信号に対し周波数分
析を行い、分析結果から原オーディオ信号帯域中に基音
と倍音が組で存在する音色成分を抽出し、抽出した音色
成分を用いて、原オーディオ信号帯域より高域側の倍音
成分を予測し原オーディオ信号に外挿するように構成し
たから、原オーディオ信号で欠落した倍音成分を復元
し、生の音楽を忠実に再現した再生が可能となる。As described above, according to the present invention, the frequency analysis means for performing frequency analysis on the original audio signal and the timbre component in which the fundamental tone and the overtone exist as a set in the original audio signal band based on the analysis result by the frequency analysis means. And an extrapolation means for extrapolating the overtone component on the high frequency side of the original audio signal band to the original audio signal by using the timbre component extracted by the extracting means. Analysis is performed, and the tonal components in which the fundamental and overtones exist as a set in the original audio signal band are extracted from the analysis results, and the extracted tonal components are used to predict the overtone components in the higher range of the original audio signal band. Since it is configured to be extrapolated to the audio signal, it is possible to reproduce the overtone component that is missing in the original audio signal and faithfully reproduce the live music.
【図１】本発明の実施例構成図である。FIG. 1 is a configuration diagram of an embodiment of the present invention.
【図２】図１中の予測部の動作を示す線図である。FIG. 2 is a diagram showing an operation of a prediction unit in FIG.
【図３】加算器出力のスペクトラムを示す線図である。FIG. 3 is a diagram showing a spectrum of an adder output.
【図４】原オーディオ信号と倍音の関係を示す線図であ
る。FIG. 4 is a diagram showing a relationship between an original audio signal and overtones.
１６ 周波数分析部 １８ 抽出部 ２０ 予測部 ３０ 外挿手段 16 frequency analysis unit 18 extraction unit 20 prediction unit 30 extrapolation means
Claims (1)
う周波数分析手段と、 周波数分析手段での分析結果から原オーディオ信号帯域
中に基音と倍音が組で存在する音色成分を抽出する抽出
手段と、 抽出手段で抽出された音色成分を用いて、原オーディオ
信号帯域より高域側の倍音成分を予測し原オーディオ信
号に外挿する外挿手段と、 を備えたことを特徴とする高域成分復元装置。1. A frequency analysis means for performing a frequency analysis on an original audio signal, and an extraction means for extracting a timbre component in which a fundamental tone and a harmonic overtone exist as a set in the original audio signal band from an analysis result of the frequency analysis means, A high-frequency component restoration characterized by including extrapolation means for predicting a harmonic component on the higher frequency side of the original audio signal band by using the timbre component extracted by the extraction means and extrapolating to the original audio signal. apparatus.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23120592A JPH0685607A (en) | 1992-08-31 | 1992-08-31 | High band component restoring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23120592A JPH0685607A (en) | 1992-08-31 | 1992-08-31 | High band component restoring device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0685607A true JPH0685607A (en) | 1994-03-25 |
Family
ID=16919990
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23120592A Withdrawn JPH0685607A (en) | 1992-08-31 | 1992-08-31 | High band component restoring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0685607A (en) |
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