KR970005609B1 - Method for regenerating voice and sound - Google Patents

Abstract

The sound field reproducing method is embodied to combine the output signals from four channels of a Dolby pro-logic decoder and the output signals from four channels of a sound filed processor to thereby generate the output signals of five channels. The sound field reproducing method comprises the steps of: combining at least one of the sound signals processed in a digital manner with the sound signals outputted through a sound filed processor; and directly outputting at least one of the sound signals processed in a digital manner to a speaker.

Description

Sound field playback method

1 is a block diagram showing one embodiment of a sound field reproduction method according to the present invention;

FIG. 2 is a detailed block diagram of the sound field processor shown in FIG.

* Explanation of symbols for main parts of the drawings

11: Dolby Pro Logic Decoder 20: sound field processing unit

30: first merge 40: second merge

210: low pass filter 220: early reflection sound generator

230: delay 240: combination

241 ~ 244: Combination filter 250: Filter part

251,252: All Pass Filter 260 ~ 290: Combiner

The present invention relates to a sound field reproduction method, and more particularly, to a sound field reproduction method for combining a four-channel signal output from a Dolby Pro Logic decoder and a four-channel signal output from a sound field processing unit to output a five-channel signal. It is about.

In general, when listening to a sound in a theater or a concert hall, the sound side, the reflected sound, etc., generated due to the inherent characteristics of the place, in addition to the actual sound, is called a sound field. In addition, the sound field is composed of a direct wave arriving from the sound source on the stage directly to the seat of the listener, and a reflected wave arriving later in time as the distance reflected from the wall or ceiling and the floor is greater than the direct wave.

A more detailed classification of the reflected waves is that the first reflected waves (called early reflections, early reflections, or primary reflections) that are reflected through the left and right walls, and then a few reflections, are randomly coming from all directions. It consists of a series of reflected waves (called high-order reflections, sub-sequent reflections, or reverberations).

For example, a movie theater showing 70 mm film is composed of a six-channel multi-track self-tape that synchronizes audio signals to the film. Therefore, since each track has its own uniqueness, that is, the direct wave and each reflected wave are output independently, the sound can be defined and expanded.

Meanwhile, movie sources recorded on video tapes of laser disk players (LDPs) for watching movies at home are widely used. In this case, since voice is composed of two channels, Dolby is used to produce surround software. A six-channel multi track must be recorded in two tracks after processing the surround encoder. In addition, during playback, the left and right signals are output from the Dolby Pro Logic Decoder, and the center and surround signals are restored.

However, the surround sound of a movie is intended to have an effect that surrounds the audience, that is, a feeling of expansion. However, in a home laser disc player or a video tape recorder, there is a problem that it is difficult to obtain sufficient expansion feeling by only two surround speakers installed behind the listener. .

The present invention is to solve the above problems, an object of the present invention is to combine the output signal of the Dolby Pro Logic Decoder and each of the signals processed by the field composed of five channels that can provide a rich sound expansion feeling The present invention provides a sound field reproduction method.

A feature of the sound field reproduction method according to the present invention for achieving the above object is a means for processing the main signal popular in the audio signal processing unit digitally, and the sound signal processed in the digital manner in a plurality of channels A sound field reproducing method comprising: sound field processing means for processing and outputting to a speaker; Combining at least one of the voice signals processed in the digital manner with the voice signals output through the sound field processing means; At least one audio signal processed by the digital method is directly output to the speaker.

Hereinafter, one preferred embodiment of the sound field reproduction method according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram showing an embodiment of a sound field reproduction method according to the present invention.

1, the left (L) and right (R) signal input terminals of the Dolby Pro Logic Decoder 10 are connected to an audio signal processor (not shown), and the left of the Dolby Pro Logic Decoder 10 is shown. The light (R) and surround (S) signal output terminals of the center (C) are connected to the respective signal input terminals of the sound field processor 20.

In addition, among the output terminals of the sound field processor 20, the front let F1 signal output terminal is connected to a speaker (not shown) through the first merge 30, and the front light FR signal output terminal is connected to the second terminal. It is connected to the speaker via the merge 40. Also, the real left RL and real light RR signal output terminals are connected to the speaker.

In addition, the left (L) signal output terminal of the Dolby Pro Logic Decoder 10 is connected to the first merge 30, the write (R) signal output terminal is connected to the second merge 40, the center (C) The signal output terminal is connected to the speaker.

The operation state will be described with reference to the above configuration.

The Dolby Pro Logic Decoder 10 receives a left (L) signal and a light (R) signal applied from an audio signal processor and processes the digital signal in a digital manner, so that the 4-channel signal, that is, the left (L), the light (R), and the center ( The signal is correctly decoded by the C) and surround S signals and output to the sound field processing unit 20 at the end. In the case of a normal stereo sound source, the stereo component of the center (C) signal of the stereo is output as the center (C) signal by the program of the directional emphasis operation, and the difference component of the left (L) and the light (R) is the surround (S) signal. Is output.

The sound field processor 20 performs sound field processing on each of the separated signals to output the front left (FL) signal to the first combiner 30, and outputs the front light (FR) signal to the second combiner 40. The left (RL) and real light (RR) signals are output to the rear speaker. In addition, the center C signal of the Dolby Pro Logic Decoder 10 is applied to the rear speaker.

In other words, a signal correctly decoded into four channels is divided into a center (C) and a light (R) (direct director) channel and a surround (S) (rear) channel of the left L, and the two different sound fields. Process data separately. The center C and the write R signals of the left L are processed into four channels of actual sound field data. Metabolism is best suited for images such as sound stereotypes, depth-of-depth effects, and feelings of spread.

The surround sound field data is processed into four channels for the surround sound signal. The surround (S) signal in the second half is the same sound field as the audience. It creates a three-dimensional sound field between the screen and the rear as well as the feeling of the rear.

On the other hand, the left (L) signal of the output signal of the Dolby Pro Logic Decoder 10 is applied to the first merge 30 is combined with the front left (FL) signal of the output signal of the sound field processing unit 20 and then output to the rear speaker The light R is applied to the second merger 40 and coupled to the front light FR signal among the output signals of the sound field processor 20 and then output to the rear speaker. Merge (30,400) Creates a synthesized sound field by superimposing the actual and surround sound fields processed separately.

As a result, the main signals L, R, and C and the surround signal S are synthesized by separate sound field processing, respectively, so that the left (L) signal and the front light (FR) signal combined with the front left (FL) signal are combined. (R) Signal and Center Signaling It consists of a total of five channels consisting of a real left signal and a real light (RR) signal. Therefore, the main signal side (L, R) is defined as the sound field on the front screen side, so that the effect sound and music are spread out on the screen, and the surround signal side (RL.RR) makes the audience feel as if they are surrounding the listener. Makes you feel the sound field.

Further, in this invention, the Dolby Pro Logic Decoder can be used in place of the directional emphasis means.

The sound field processing unit 20 will be described in detail with reference to FIG. 2.

2 is a detailed block diagram of the sound field processing unit 20 shown in FIG.

2, the signal input terminal is connected to the input terminal of the low pass filter 210 for adjusting the frequency, and the output terminal of the low pass filter 210 of the initial reflection generator 22 for generating the initial reflection sound. It is connected to the input terminal.

In addition, a branch between the signal input terminal and the low pass filter 210 is connected to the input terminal of the delay unit 230 for adjusting the reverberation delay time, and the output terminal of the delay unit 230 has four combination filters 241 to 241. It is connected to the input terminal of the combination unit 240 consisting of 244, the output terminal of each combination filter (241 ~ 244) is connected to the input terminal of the filter unit 250 consisting of two all-pass filters (251, 252) connected directly have. In addition, the output terminal of the filter unit 250 is branched and connected to four couplers 260 to 290 so as to be coupled to the respective output terminals FL, FR, RL and RR of the initial reflection sound generator 220, respectively.

The operation will be described with reference to the above circuit.

The left (L), light (R), center (C), and surround (S) signals input through the signal input terminal are output after the frequency is adjusted according to the property of the wall through the low pass filter 210. The signal output through the low pass filter 210 generates an initial reflection sound through the initial reflection sound generator 220.

In addition, the signal input through the signal input terminal is input to the delay unit 230 to adjust the reverberation delay time of the reflected wave, the adjusted signal is a combination filter (241 ~ 244) and the filter for each combination configured in the combination unit 240 It is input to all-pass filters 251 and 252 configured in the unit 250.

Since the frequency characteristics of the combination unit 240 are not smooth, the filter unit 250 having the smooth frequency characteristics is used to eliminate the loss that occurs when the frequency characteristics are not peaceful, and a finer pattern in the time domain. To create a more vivid sound field. In addition, the output signal of the delay unit 230, the combination unit 240 and the filter unit 250 is coupled to the output signal of the early reflection sound generator 220 through the combiner (260 ~ 290), the initial reflection sound and the reverberation sound Combined front left (FL), front light (FR), real left (RL), real light (RR) signals are generated.

As described above, according to the sound reproducing method according to the present invention, by outputting the sound field processing of the main output signal of the Dolby Pro Logic Decoder, there is an effect that the viewer can feel a rich sound field like a 70mm theater as five speakers. .

Claims (2)

A sound field reproduction method for reproducing a sound field, comprising a digital signal processing means of a main signal applied by an audio signal processing unit, and a sound field processing means for processing the digitally processed voice signal into a plurality of channels and outputting the same to a speaker. To; Combining at least one of the voice signals processed in the digital manner with the voice signals output through the sound field processing means; And at least one of the audio signals processed by the digital method is directly output to the speaker. The sound field reproduction method of claim 1, wherein the left signal and the write signal of the digitally processed voice signals are output in combination with the front left signal and the front light signal processed through at least one combining means.