CN103686544A - A synthetic method for audio signals - Google Patents

Abstract

The invention provides a synthetic method for audio signals. The method specifically comprises the following steps: present positional information of audio frequency points in a simulation audio frequency field are obtained according to a predetermined frequency; parameters of audio signals in each sound channel of stereophonic sounds are determined according to the present positional information of the audio frequency points; audio signals in a time period corresponding to the preset frequency are extracted, and the extracted audio signals are distributed to each sound channel of the stereophonic sounds according to the parameters, so that the extracted audio signals are converted into the stereophonic sounds. According to the invention, users are enabled to adjust sound effects of the stereophonic sounds according to their own demands, so that the experience of the users is improved.

Description

A kind of synthetic method of audio signal

Technical field

The present invention relates to the synthetic method in audio signal processing technique field, particularly a kind of audio signal.

Background technology

Monophony is more original sound reproduction form, is that after the audio signal from different azimuth is mixed, unification is recorded it by recording equipment, then is reset by an audio amplifier.Stereo reality is assigned to a plurality of different sound channels by audio signal, and the direction of each sound source in original signal is reproduced, and makes appreciator have a kind of sensation of being surrounded by the sound from different directions.

At present, 5.1 channel stereo have been widely used in all kinds of traditional cinema and home theater.5.1 channel stereo are to there being 6 sound channels, 3 preposition sound channels: L channel (L), R channel (R) and center channels (C), 2 rearmounted stereo channels: leftstereophonic channel (SL) and right stereo channel (SR), finally also have a mega bass sound channel (SW), be conventionally also referred to as 0.1 sound channel.In 5.1 channel stereo audio amplifier groups, each sound channel is to be mutually independent, and can send respectively different sound, and finally the central authorities 5 full range range sound channels form a perfect stereophonic field.7.1 up-to-date channel stereo than more than 5.1 two side stereo channels, representing of sound is more perfect.

Stereo to there being the audio signal of a plurality of sound channels, take 5.1 channel stereo as example, when compound stereoscopic sound, for 6 sound channels, collect 6 different monaural audio signals, by 6 sound channels, play respectively, or a monaural audio signal is sent to respectively to 6 sound channels play.

Above problems of the prior art are: if with 6 different monaural audio signal compound stereoscopic sound, need to go to collect different monaural audio signals, comparatively bother; If directly play 6 sound channels with same monophonic audio signal, because the sound of each sound channel is the same, integral sound effect is unsatisfactory.

Summary of the invention

For this reason, the present invention proposes a kind of synthetic method of audio signal, can eliminate fully one or more problems that restriction and defect due to prior art cause.

Additional advantages of the present invention, object and characteristic, a part will be elucidated in the following description, and another part will be significantly or be acquired from enforcement of the present invention by the investigation of the explanation to below for those of ordinary skill in the art.By the structure of pointing out especially in the specification at word and claims and accompanying drawing, can realize and obtain the object of the invention and advantage.

The synthetic method that the invention provides a kind of audio signal, is characterized in that, described method specifically comprises the following steps:

According to preset frequency, obtain the current location information of analogue audio frequency field middle pitch frequency;

According to the current location information of described audio frequency point, determine that audio signal is in the parameter of stereo each sound channel;

Extract the audio signal in the time cycle that described predeterminated frequency is corresponding, and according to described parameter, the audio signal of extraction is distributed to stereosonic each sound channel, thereby the audio signal of extraction is converted into stereo.

Preferably, described stereo be 5.1 channel stereo or 7.1 channel stereo.

Preferably, when described audio signal is monophonic audio signal, according to following formula, monaural audio signal is distributed to 5.1 stereosonic each sound channels:

$\left[\begin{array}{c}L\\ R\\ C\\ \mathrm{LS}\\ \mathrm{RS}\end{array}\right]=\left[\begin{array}{c}A11\\ A22\\ A33\\ A44\\ A55\end{array}\right]*I.$

Preferably, when described audio signal is monophonic audio signal, according to following formula, monaural audio signal is distributed to 7.1 stereosonic each sound channels:

$\left[\begin{array}{c}L\\ R\\ C\\ \mathrm{LSR}\\ \mathrm{RSR}\\ \mathrm{LSS}\\ \mathrm{RSS}\end{array}\right]=\left[\begin{array}{c}A11\\ A22\\ A33\\ A44\\ A55\\ A66\\ A77\end{array}\right]*].$

Preferably, the described step of the audio signal of extraction being distributed to stereosonic each sound channel according to described parameter comprises:

In the audio signal receiving, extract the audio signal of preset ratio and distribute to stereosonic low frequency audio sound channel;

To distribute to remaining audio signal after low frequency audio sound channel, according to described allocation of parameters, distribute to stereosonic all the other sound channels.

Preferably, described audio signal comprises one or more, and described audio signal comprises when a plurality of, by each audio signal be converted into stereo after, described method also comprises:

For each audio signal, transform obtain stereo, use audio mix equipment respectively the audio signal of same sound channel to be mixed, one of corresponding generation is stereo.

Preferably, when described audio signal is while being stereo, described audio frequency point has two, to having two positional informations and two groups of allocation of parameters.

Preferably, described stereo audio output apparatus or the VU volume indicator of sending to.

User of the present invention can adjust sound image point position in simulated sound image field, according to the position of current acoustic image point, can determine the allocation of parameters of monophonic audio signal in stereo each sound channel, according to allocation of parameters, just monophonic audio signal can be distributed to stereosonic each sound channel, also just form stereo.Without user, collect 6 different monaural audio signals on the one hand, on the other hand, due to the adjustment of sound image point position, the allocation of parameters of monophonic audio signal can be adjusted thereupon, thereby makes user adjust stereosonic audio by the demand of oneself.

Accompanying drawing explanation

Fig. 1 is according to the flow chart of the synthetic method embodiment of the present invention, audio signal.

Embodiment

Below in conjunction with accompanying drawing, embodiment of the present invention is described further.

As shown in Figure 1, the synthetic method of described audio signal specifically comprises the following steps:

Step 101, according to preset frequency, obtain the current location information of analogue audio frequency field middle pitch frequency.

In the application, described stereo can be 5.1 channel stereo or 7.1 channel stereo.In 5.1 sound channel systems, adopt the sound channel output sound of L channel (L), middle sound channel (C), R channel (R), left back sound channel (LS), five directions of right back sound channel (RS), five sound channels are separate, are distributed in user's surrounding.Wherein, " .1 " sound channel (LFE sound channel) is a custom-designed subwoofer sound channel.7.1 stereosonic sound channels have been arranged than 5.1 more than being exactly two side stereo channel LSS and RSS.

The audio that the application provides an analogue audio frequency field to simulate stereo, for example, the analogue audio frequency field of 7.1 channel stereo, three some correspondences of the top be the putting position of L, C, these three corresponding audio amplifiers of sound channel of R, two middle some correspondences be the putting position of LSS and these two corresponding audio amplifiers of sound channel of RSS, two some correspondences of below is the putting position of LSR and these two corresponding audio amplifiers of sound channel of RSR, and the position of middle audio frequency point has represented the sound intensity of each sound channel of hearing.For example, these three audio amplifiers of current audio frequency point position and L, C and LSS are nearest, and distance is identical, and slightly far away with R, LRS and these three audio amplifier distances of RSS, distance R SR farthest.

In the application, describedly stereoly can send to audio output apparatus (for example audio amplifier) or VU volume indicator, whether the audio that user can play according to audio output apparatus meets the needs of oneself, or the Output rusults of observation VU volume indicator, decides positional information how to adjust audio frequency point.

More specifically, user can pass through to adjust the position of analogue audio frequency field middle pitch frequency, or adjusts the position coordinates of analogue audio frequency field middle pitch frequency, changes the positional information of described audio frequency point.

Audio signal in the application can comprise monophonic audio signal or stereo, stereoly can comprise 2 monaural audio signals, is respectively L channel (L) and R channel (R).

When described audio signal is while being stereo, corresponding can have two analogue audio frequency fields, has accordingly two audio frequency points, respectively corresponding L channel and R channel.When two audio frequency points are adjusted, can to two mirror points, adjust respectively, the pass that two audio frequency points also can be set is interlock adjustment, when one of them audio frequency point is adjusted, another audio frequency point can carry out same adjustment or mirror image adjustment automatically, when one of them audio frequency point is adjusted, another audio frequency point can carry out the reverse adjustment in left and right automatically, and for example, when by an audio frequency point, below is adjusted left, another audio frequency point can corresponding adjusting to lower right.

The current location information of step 102, the described audio frequency point of foundation, determines that audio signal is in the parameter of stereo each sound channel.

What each summit in audio field was corresponding is stereosonic each sound channel, when audio frequency point distance A summit is nearer than B summit, the intensity that represents the audio signal in sound channel corresponding to A summit that user hears can be larger than B summit, so, audio signal also can be greater than B summit accordingly in the allocation of parameters of sound channel corresponding to A summit.

Particularly, can be according to the ratio of the distance of audio frequency point and each sound channel, determine that audio signal is in the allocation proportion of each sound channel, when user changes the position of audio frequency point, also just there is change in the allocation of parameters of stereo each sound channel in corresponding audio signal, user can adjust stereosonic audio by the demand of oneself.

Audio frequency point distance L SR and RSR are far away, can think that voice signal is absorbed by LSS and RSS sound channel, and audio signal is that 0, R sound channel is in like manner stopped by C sound channel in the allocation of parameters of LSR and RSR sound channel, and audio signal is 0 in the allocation of parameters of C sound channel.

Suppose that LFE has distributed 20% audio signal, for remaining 4 sound channels, the audio signal of L and C sound channel is added up, equate with the audio signal sum of LSS and RSS sound channel, the allocation of parameters sum of L and C sound channel is (1-20%) * 0.5=0.4, and the allocation of parameters sum of LSS and RSS sound channel is (1-20%) * 0.5=0.4.Meanwhile, because L and C sound channel equate with the distance of audio frequency point, therefore, it is 0.4 * 0.5=0.2 that the allocation of parameters of L and C sound channel is; The horizontal range ratio of LSS and RSS sound channel and audio frequency point is 1: 3, and allocation of parameters ratio should be 3: 1 mutually, and therefore, it is 0.4 * 3/4=0.3 that the allocation of parameters of LSS is, and the allocation of parameters of RSS sound channel is for being 0.4 * 1/4=0.1

When described audio signal is while being stereo, two audio frequency points are to there being two positional informations, and two groups of allocation of parameters.

Step 103, according to described parameter, audio signal is distributed to stereosonic each sound channel.

According to described allocation of parameters, audio signal is distributed to stereosonic each sound channel, that is to say the audio signal of extracting in the time cycle that described predeterminated frequency is corresponding, and according to described allocation of parameters, the audio signal of extraction is converted into stereo.For example, according to the frequency of 40ms, go to obtain the positional information of current audio frequency point, corresponding, extract current time backward the audio signal in 40ms process.

In embodiments of the present invention, described step 103 can comprise:

Sub-step S11, in the audio signal receiving, extract the audio signal of preset ratio and distribute to stereosonic low frequency audio sound channel;

Sub-step S12, will distribute to remaining audio signal after low frequency audio sound channel, according to described allocation of parameters, distribute to stereosonic all the other sound channels.

Stereoly comprise a subwoofer sound channel, it is LFE sound channel, a plurality of sound channels in audio field do not comprise LFE sound channel, therefore, the application is before distributing audio signal according to allocation of parameters, can will first distribute the part of preset ratio to low frequency audio sound channel, when LFE sound channel is play the audio signal being assigned to, can carry out filtering by software, retain the low frequency signal that is less than predeterminated frequency, or by Super Bass Loudspeaker Enclosure, audio signal is carried out to low frequency filtration, only play low frequency signal, generally can using frequency lower than 120HZ audio signal as low frequency signal.

The audio signal of preset ratio is distributed to after LFE sound channel, can remaining audio signal be assigned to stereosonic each sound channel according to allocation of parameters.

When described audio signal is monophonic audio signal, monaural audio signal is distributed to 5.1 stereosonic each sound channels, can be with reference to formula below:

$\left[\begin{array}{c}L\\ R\\ C\\ \mathrm{LS}\\ \mathrm{RS}\end{array}\right]=\left[\begin{array}{c}A11\\ A22\\ A33\\ A44\\ A55\end{array}\right]*I.$

Wherein, I is the remaining audio signal of distributing to after LFE sound channel, A11-A55..... be that according to the positional information calculation of audio frequency point out, in the allocation of parameters of remaining five sound channels, what L, R, C, LS and RS were corresponding is the allocation result of 5.1 stereosonic five sound channels.

When described audio signal is monophonic audio signal, monaural audio signal is distributed to 7.1 stereosonic each sound channels, can be with reference to formula below:

$\left[\begin{array}{c}L\\ R\\ C\\ \mathrm{LSR}\\ \mathrm{RSR}\\ \mathrm{LSS}\\ \mathrm{RSS}\end{array}\right]=\left[\begin{array}{c}A11\\ A22\\ A33\\ A44\\ A55\\ A66\\ A77\end{array}\right]*]$

Wherein, I is the remaining audio signal of distributing to after LFE sound channel, A11-A77..... be that according to the positional information calculation of audio frequency point out, in the allocation of parameters of remaining five sound channels, what L, R, C, LSR, RSR, LSS and RSS were corresponding is the allocation result of 7.1 stereosonic seven sound channels.

When described audio signal is while being stereo, by stereo 5.1 stereosonic each sound channels of distributing to, can be with reference to formula below:

$\left[\begin{array}{c}L\\ R\\ C\\ \mathrm{LS}\\ \mathrm{RS}\end{array}\right]=\left[\begin{array}{c}A11A12A13A14A15\\ A21A22A23A24A25\end{array}\right]*\left[\begin{array}{c}L\\ R\end{array}\right]$

Wherein, $\left[\begin{array}{c}L\\ R\end{array}\right]$ For distributing to the remaining audio signal after LFE sound channel, A11-A25..... is that according to the positional information calculation of two audio frequency points out, in the allocation of parameters of all the other five sound channels, what L, R, C, LS and RS were corresponding is the allocation result of 5.1 stereosonic five sound channels.

When described audio signal is while being stereo, by stereo 7.1 stereosonic each sound channels of distributing to, can be with reference to formula below:

$\left[\begin{array}{c}L\\ R\\ C\\ \mathrm{LSR}\\ \mathrm{RSR}\\ \mathrm{LSS}\\ \mathrm{LSS}\end{array}\right]=\left[\begin{array}{c}A11A12A13A14A15A16A17\\ A21A22A23A24A25A26A27\end{array}\right]*\left[\begin{array}{c}L\\ R\end{array}\right]$

$\left[\begin{array}{c}L\\ R\end{array}\right]$ For distributing to the remaining audio signal after LFE sound channel, A11-A27..... be according to the positional information calculation of two audio frequency points out, in the allocation of parameters of all the other seven sound channels, what L, R, C, LSR, RSR, LSS and RSS were corresponding is the allocation result of 5.1 stereosonic seven sound channels.

Further, described audio signal includes one or more, and described audio signal comprises when a plurality of, by each audio signal be converted into stereo after, described method also comprises:

For each audio signal, transform obtain stereo, use audio mix equipment respectively the audio signal of same sound channel to be mixed, one of corresponding generation is stereo.

Audio signal comprises when a plurality of, for each audio signal can obtain one corresponding stereo, audio mix equipment (for example, AudioMixer) by the sound of each stereosonic same sound channel is mixed, just a plurality of stereo mix can be become one stereo.

In sum, according to the application, user can adjust audio frequency point position in analogue audio frequency field, according to the position of current audio frequency point, can determine the allocation of parameters of monophonic audio signal in stereo each sound channel, according to allocation of parameters, just monophonic audio signal can be distributed to stereosonic each sound channel, also just form stereo.Without user, collect 6 different monaural audio signals on the one hand, on the other hand, due to the adjustment of audio frequency point position, the allocation of parameters of monophonic audio signal can be adjusted thereupon, thereby makes user adjust stereosonic audio by the demand of oneself.

And the application is dividing timing according to allocation of parameters to audio signal, the part that first filters out low frequency can be distributed to low frequency audio sound channel, avoid low frequency signal to affect each sound channel.

The application's method equally can be for by the stereo compound stereoscopic sound of a plurality of sound channels, and by a plurality of monophonic audio signals or the situation of a plurality of stereo compound stereoscopic sound.

For embodiment of the method, for simple description, therefore it is all expressed as to a series of combination of actions, but those skilled in the art should know, the application is not subject to the restriction of described sequence of movement, because according to the application, some step can adopt other orders or carry out simultaneously.Secondly, those skilled in the art also should know, the embodiment described in specification all belongs to preferred embodiment, and related action and module might not be that the application is necessary.

The application can be used in numerous general or special purpose computingasystem environment or configuration.For example: personal computer, server computer, handheld device or portable set, plate equipment, multicomputer system, the system based on microprocessor, set top box, programmable consumer-elcetronics devices, network PC, minicom, mainframe computer, comprise distributed computing environment (DCE) of above any system or equipment etc.

The application can describe in the general context of the computer executable instructions of being carried out by computer, for example program module.Usually, program module comprises the routine carrying out particular task or realize particular abstract data type, program, object, assembly, data structure etc.Also can in distributed computing environment (DCE), put into practice the application, in these distributed computing environment (DCE), by the teleprocessing equipment being connected by communication network, be executed the task.In distributed computing environment (DCE), program module can be arranged in the local and remote computer-readable storage medium that comprises memory device.

Above content is only preferred embodiment of the present invention, for those of ordinary skill in the art, according to thought of the present invention, all will change in specific embodiments and applications, and this description should not be construed as limitation of the present invention.

Claims (8)

1. a synthetic method for audio signal, is characterized in that, described method specifically comprises the following steps:

According to preset frequency, obtain the current location information of analogue audio frequency field middle pitch frequency;

According to the current location information of described audio frequency point, determine that audio signal is in the parameter of stereo each sound channel;

Extract the audio signal in the time cycle that described predeterminated frequency is corresponding, and according to described parameter, the audio signal of extraction is distributed to stereosonic each sound channel, thereby the audio signal of extraction is converted into stereo.

2. the synthetic method of audio signal according to claim 1, is characterized in that, described stereo be 5.1 channel stereo or 7.1 channel stereo.

3. the synthetic method of audio signal according to claim 2, is characterized in that, when described audio signal is monophonic audio signal, according to following formula, monaural audio signal is distributed to 5.1 stereosonic each sound channels:

$\left[\begin{array}{c}L\\ R\\ C\\ \mathrm{LS}\\ \mathrm{RS}\end{array}\right]=\left[\begin{array}{c}A11\\ A22\\ A33\\ A44\\ A55\end{array}\right]*I.$

4. the synthetic method of audio signal according to claim 2, is characterized in that, when described audio signal is monophonic audio signal, according to following formula, monaural audio signal is distributed to 7.1 stereosonic each sound channels:

$\left[\begin{array}{c}L\\ R\\ C\\ \mathrm{LSR}\\ \mathrm{RSR}\\ \mathrm{LSS}\\ \mathrm{RSS}\end{array}\right]=\left[\begin{array}{c}A11\\ A22\\ A33\\ A44\\ A55\\ A66\\ A77\end{array}\right]*I.$

5. the synthetic method of audio signal according to claim 1, is characterized in that, the described step of the audio signal of extraction being distributed to stereosonic each sound channel according to described parameter comprises:

In the audio signal receiving, extract the audio signal of preset ratio and distribute to stereosonic low frequency audio sound channel;

To distribute to remaining audio signal after low frequency audio sound channel, according to described allocation of parameters, distribute to stereosonic all the other sound channels.

6. the synthetic method of audio signal according to claim 1, is characterized in that, described audio signal comprises one or more, and described audio signal comprises when a plurality of, by each audio signal be converted into stereo after, described method also comprises:

For each audio signal, transform obtain stereo, use audio mix equipment respectively the audio signal of same sound channel to be mixed, one of corresponding generation is stereo.

7. the synthetic method of audio signal according to claim 2, is characterized in that, when described audio signal is while being stereo, described audio frequency point has two, to having two positional informations and two groups of allocation of parameters.

8. the synthetic method of audio signal according to claim 2, is characterized in that, described stereo audio output apparatus or the VU volume indicator of sending to.

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