CN101594186B - Method and device generating single-channel signal in double-channel signal coding - Google Patents

Abstract

The invention provides a method and a device for generating single-channel signals in double-channel signal coding. The method mainly comprises the following steps: when corresponding delay between current frame channels in the first channel is inconsistent with corresponding delay between previous frame channels, signals with certain length from the end of the previous frame are compressed or expanded so as to obtain signals with specified length; the signals with specified length and the corresponding signals in the second channel are performed with sum operation to generate single-channel signals; and according to corresponding delay between current frame channels, other signals except signals with specified length in the current frame and the corresponding signals in the second channel are performed with sum operation to generate single-channel signals. The invention can generate continuous single-channel signals when the corresponding delays between adjacent two frame channels are inconsistent.

Description

The method and apparatus of generating single-channel signal in double-channel signal coding

Technical field

The present invention relates to the media coding technology, relate in particular to a kind of generation method and apparatus of single-channel signals in double-channel signal coding.

Background technology

In mobile communication and IP communication, along with wideband transmit is more and more universal, various broadband services are also more and more abundanter, need high-quality audio frequency and speech communication in various broadband services.For example, the speech communication in the hand-held visual telephone business, the speech communication of video conferencing system, and high-quality voice and three-dimensional environment in the multi-point communication.

At present, high-quality stereosonic speech communication has obtained than faster development.Stereo voice signal is being carried out in the coding transmission, adopting single channel-stereo embedded extendible configuration, can better recover single channel and stereosonic signal to reach at receiving end.

Existing multi-channel coding technology is divided into roughly two classes: parameter coding technology and nonparametric coding techniques.In the nonparametric coding techniques, different passages are independently encoded.The parameter coding technology utilizes interchannel simple crosscorrelation to go redundant the processing, and stops code rate to be doubled and redoubled with port number.

A kind of structural representation of typical parameter stereo framework as shown in Figure 1.Left and right sides passage is at first by sneaking out down the stronger single channel signal of Cheng Shengcheng and limit signal, sneak out journey under this and need to take full advantage of the interchannel correlativity in the left and right sides, extract to greatest extent the difference on the interchannel amplitude in the left and right sides and the time delay, realize generating maximum single channel signal.The single channel signal and the limit signal that generate are sent in core encoder and the stereophonic encoder, then, the signal of core encoder and stereophonic encoder output are carried out code stream is synthetic to be processed.

The schematic diagram of a kind of lower method of sneaking out journey that realizes stereo framework of the prior art as shown in Figure 2.Concrete processing procedure is:

Carry out interchannel prediction and analyzing and processing and obtain the interchannel Prediction Parameters, this prediction and analyzing and processing need to take full advantage of the correlativity between first passage and second channel, obtain the poor and Amplitude Ratio of delay between first passage and second channel; According to the above-mentioned Prediction Parameters of obtaining, i.e. delay between first passage and second channel is poor obtains the medium range forecast parameter with Amplitude Ratio; Utilize the medium range forecast parameter of above-mentioned acquisition and the prediction signal of the first and second passages to generate single channel signal.In realizing process of the present invention, the inventor finds to have following at least one shortcoming in the above-mentioned prior art: when the interchannel delay of adjacent two frames in front and back is inconsistent, there is discontinuous phenomenon in the single channel signal that generates in interframe, and this discontinuous phenomenon can cause the Efficiency Decreasing of core encoder.

Summary of the invention

The purpose of this invention is to provide a kind of generation method and apparatus of single-channel signals in double-channel signal coding, thereby can solve the problem that there is non-continuous event in single channel signal.

The objective of the invention is to be achieved through the following technical solutions:

A kind of generation method of single-channel signals in double-channel signal coding comprises:

When the interchannel correlation delay of former frame in the interchannel correlation delay of present frame in the first passage and the described first passage is inconsistent, the signal of the partial-length that the ending of former frame from described first passage is begun compresses or expands, obtain the signal of designated length, the value of described partial-length and designated length is more than or equal to the difference between the interchannel correlation delay of the interchannel correlation delay of described former frame and described present frame;

Signal and the signal corresponding to the signal with described designated length in the second channel of the designated length in the described first passage are carried out generating single pass signal with computing, after other signal outside the designated length described in the present frame in the described first passage postponed according to the interchannel correlation delay of present frame, and the respective signal in the second channel carries out generating single pass signal with computing.

A kind of generating apparatus of single-channel signals in double-channel signal coding comprises:

Signal adjusting module, be used for when the interchannel correlation delay of former frame in the interchannel correlation delay of first passage present frame and the described first passage is inconsistent, the signal of the partial-length that the ending of former frame from described first passage is begun compresses or expands, obtain the signal of designated length, the value of described partial-length and designated length is more than or equal to the difference between the interchannel correlation delay of the interchannel correlation delay of described former frame and described present frame;

The signal generation module, be used for signal and the signal corresponding to the signal with described designated length in the second channel of the designated length of described first passage present frame are carried out generating single pass signal with computing, after other signal outside the designated length described in the described present frame is postponed according to the interchannel correlation delay of present frame and the respective signal in the second channel carry out generating single pass signal with computing.

As seen from the above technical solution provided by the invention, the embodiment of the invention postpones when inconsistent by the interchannel correlativity at the front and back frame, by becoming the method for sampling signal is compressed or expands, so that the delay of signal changes smoothly in interframe, thereby guaranteed the continuity of the single channel signal of generation, further improved the code efficiency of core encoder.

Description of drawings

Fig. 1 is the structural representation of a kind of typical parameter stereo framework in the prior art;

Fig. 2 is a kind of lower schematic diagram of sneaking out the method for journey of realizing stereo framework of the prior art;

The processing flow chart of the generation method of the single channel signal that Fig. 3 provides for the embodiment of the invention;

Fig. 4 postpones maximal correlation less than former frame when postponing for what the embodiment of the invention provided at the maximal correlation of present frame, postpones the single channel signal that inconsistent method generates according to the maximal correlation between considered frame not and has discontinuous situation synoptic diagram;

When the maximal correlation at present frame that Fig. 5 provides for the embodiment of the invention postpones less than the maximal correlation delay of former frame, with the continuous single channel signal synoptic diagram that becomes method of sampling generation;

When the maximal correlation at present frame that Fig. 6 provides for the embodiment of the invention postpones greater than the maximal correlation delay of former frame, with the continuous single channel signal synoptic diagram that becomes method of sampling generation;

The structural representation of the generating apparatus of the single-channel signals in double-channel signal coding that Fig. 7 provides for the embodiment of the invention;

Fig. 8 is the application scenarios synoptic diagram of the generating apparatus of the described single-channel signals in double-channel signal coding of the embodiment of the invention.

Embodiment

In embodiments of the present invention, the interchannel related function of present frame is weighted processing by weighting function, obtains the maximal value of the related function after weighting is processed, this maximal value is defined as the interchannel correlation delay of described present frame.Equally, according to above-mentioned processing procedure, obtain the interchannel correlation delay of former frame.

When the interchannel correlation delay of the interchannel correlation delay of present frame in the first passage and former frame was inconsistent, the signal of the partial-length that the ending from described former frame is begun compressed or expand by becoming the method for sampling, the signal of acquisition designated length.The value of described partial-length and designated length is more than or equal to the difference between the interchannel correlation delay of the interchannel correlation delay of described present frame and described former frame.

Then, signal and the respective signal in the second channel of described designated length are carried out generating single pass signal with computing, after other signal outside the designated length described in the described present frame postponed according to the interchannel correlation delay of present frame, and the respective signal in the second channel carries out generating single pass signal with computing.

Describe the embodiment of the invention in detail below in conjunction with accompanying drawing, take the binary channels stereo audio coding as example, the treatment scheme of the generation method of the single-channel signals in double-channel signal coding that the embodiment of the invention provides comprises the steps: as shown in Figure 3

Step 31, the interchannel related function in the left and right sides is weighted processing, obtains the interchannel maximal correlation in the left and right sides and postpone.

By weighting function right passage is weighted processing with respect to the related function of left passage, obtains the maximal value of the related function after weighting is processed, this maximal value is defined as right passage postpones with respect to the maximal correlation of left passage.Equally, according to above-mentioned processing procedure, obtain left passage with respect to the maximal correlation delay of right passage.

Suppose that left-channel signal is L (n), right channel signal is R (n).

For certain Frame, right passage with respect to the related function of left passage is:

$r_{\mathrm{rl}}\left(m\right)=\underset{n=0}{\overset{N-1}{\mathrm{\Σ}}}L\left(n\right)R(n-m),$ Left passage with respect to the related function of right passage is:

$r_{\mathrm{lr}}\left(m\right)=\underset{n=0}{\overset{N-1}{\mathrm{\Σ}}}R\left(n\right)L(n-m).$

Wherein, n is from 0 to N-1, and m is from 0 to M-1, and N is the length of above-mentioned Frame, and M is the maximal value of left and right sides channel delay, and a n is corresponding to a sampled point in above-mentioned certain Frame.

In order to reduce the error of above-mentioned related function, avoid simultaneously the variation of predicted value too fast, the embodiment of the invention is weighted processing by weighting function w (m) to above-mentioned related function, and this weighting treatment step comprises:

r _rlw(m)＝r _rl(m)*w(m)

r _lrw(m)＝r _lr(m)*w(m)

Wherein, weighting function w (m) can be the function of linear decrease, also can be the weighting function of other form.

Ask for the r after the above-mentioned weighting _Rlw(m) maximal value, n corresponding to this maximal value is D _Rm, that is: r _Rl(D _Rm)=max (r _Rlw(m)), this D _RmBe right passage with respect to the maximal correlation delay of left passage.

Ask for the r after the above-mentioned weighting _Lr(D _Lm) maximal value, n corresponding to this maximal value is D _Lm, that is: r _Lr(D _Lm)=max (r _Lrw(m)), this D _LmBe left passage with respect to the maximal correlation delay of right passage.

According to above-mentioned processing procedure, can calculate the right passage of present frame in the right passage with respect to the maximal correlation delay of left passage, this maximal correlation postpones to be the interchannel correlation delay of present frame in the right passage.

Can calculate equally the interchannel correlation delay of former frame in the right passage, and the interchannel correlation delay of present frame and former frame in the left passage.

Step 32, when the interchannel correlation delay that has interframe is inconsistent, come left passage or right passage are expanded and compressed by becoming the method for sampling, generate continuous single channel signal.

The below is with fixing left passage, and right passage is expanded or the boil down to example illustrates the treatment scheme of the described method of the embodiment of the invention.In actual applications, can also fix right passage, left passage is expanded or compressed.

When the interchannel correlation delay of the interchannel correlation delay of present frame in the right passage and former frame was inconsistent, the signal of the partial-length that the ending of former frame from right passage is begun compressed or expands, and obtains the signal of designated length.The value of described partial-length and designated length must be more than or equal to the difference between the interchannel correlation delay of the interchannel correlation delay of described former frame and described present frame, such as, can be the integral multiples such as 3 or 4 of this difference, thereby can guarantee the gap between described former frame and the present frame is filled fully, perhaps, the lap between described former frame and the present frame is replaced fully.

The signal corresponding with the signal of described designated length in the signal of designated length described in the right passage and the left passage carried out generating single pass signal with computing.After other signal outside the designated length described in the present frame of right passage postponed according to the interchannel correlation delay of above-mentioned present frame, and the respective signal in the left passage carries out generating single pass signal with computing.

After having obtained above-mentioned interchannel correlation delay for certain frame, in the inconsistent situation of interchannel correlation delay between considered frame not, take fixing left passage as example, the single channel signal of generation is: M (n)=gl*L (n)+gr*R (n-D _Rm)

Above-mentioned gl and gr are the gain of left and right sides passage, and the below illustrates the embodiment of the invention as an example of gl=gr=1/2 example, and gl and gr can also get other values.

In actual applications, the interchannel correlation delay D of the present frame in the right passage (when fixing right passage, then being left passage) _RmcInterchannel correlation delay D with former frame _RmpOften inconsistent, such as, D _Rmc＜D _Rmp, at this moment, according to the single channel signal of the inconsistent method generation of the above-mentioned not interchannel correlation delay between considered frame, with the discontinuous situation that exists as shown in Figure 4.When the single channel signal that generates is encoded, because the discontinuous meeting of signal causes the decline of code efficiency.

It is a process that changes slowly that the embodiment of the invention is set the interchannel correlativity delay in the left and right sides, works as D _RmcAnd D _RmpWhen inconsistent, think in right passage that it is from D that the interframe of the forward part of present frame postpones relatively _RmpLinear change is to D _Rmc, utilize to become the method for sampling signal of right channel middle minute length is carried out compression/extension, cause the non-continuous event of the single channel signal that generates to reach the sudden change of eliminating inter-frame delay, the above-mentioned partial section in the past end of frame begins to choose.

The signal that the signal of right channel middle minute length carries out the designated length that obtains after compression/extension is processed is

The above-mentioned change method of sampling exists multiple, and the embodiment of the invention adopts the method for Band-limited interpolation, but is not limited to the method for Band-limited interpolation.

Delay D when the front and back frame _Rmp, D _RmcIn the not identical situation, comprise two kinds of situations, D _Rmp＞D _RmcAnd D _Rmp＜D _Rmc, below just respectively both of these case is described:

1, works as D _Rmp＞D _RmcThe time, according to formula M (n)=(L (n)+R (n-D _Rm))/process of 2 single channel signals that calculate to generate in, have the space at the present frame of right passage and the junction of previous frame, the length in space is D _Rmp-D _Rmc, namely there is the situation of lost part signal in right passage.

For solving the problem of above-mentioned dropout, will count from the ending of the upper frame of right passage, length is K* (D _Rmp-D _Rmc) signal by becoming Sampling techniques boil down tos (K-1) * (D _Rmp-D _Rmc) signal, above-mentioned K is predefined numerical value, can be 4 or 3 etc., namely partial-length is K* (D _Rmp-D _Rmc), designated length is (K-1) * (D _Rmp-D _Rmc).Namely realize the part signal in the present frame is filled in the above-mentioned space, thereby guaranteed the continuity of signal in the right passage.

Coming compressed signal by the method for Band-limited interpolation is relatively more classical method, needs to design different coefficients according to performance requirement in application, processes to finish by carrying out up-sampling, filtering and down-sampling.Current maximal correlation in conjunction with right passage postpones, the right channel signal after compression is processed For:

${\hat{R}}_c\left(n\right)=\left\{\begin{array}{cc}\hat{R}e& n<(K-1)*(D_{\mathrm{rmp}}-D_{\mathrm{rmc}})\\ R(n-D_{\mathrm{rmc}})& n\&GreaterEqual;(K-1)*(D_{\mathrm{rmp}}-D_{\mathrm{rmc}})\end{array}\right.$

A sampled point in above-mentioned certain Frame of above-mentioned n representative, (K-1) * (D _Rmp-D _Rmc) the value of designated length after representative compression is processed,

The signal of the designated length after the representative compression is processed.

2, work as D _Rmp＜D _RmcThe time, according to formula M (n)=(L (n)+R (n-D _Rm))/process of 2 single channel signals that calculate to generate in, in the junction of right passage present frame and previous frame overlapping phenomenon is arranged, the length of overlapping interval is: D _Rmc-D _Rmp, namely there is the situation of signal overlap in right passage.

For solving the problem of above-mentioned signal overlap, by counting from the ending of frame on the right passage, length is (K-1) * (D _Rmc-D _Rmp) signal expand to (K) * (D by becoming Sampling techniques _Rmc-D _Rmp) signal, namely partial-length is (K-1) * (D _Rmc-D _Rmp), designated length is K* (D _Rmc-D _Rmp).Realized the part signal in the present frame is filled in the above-mentioned overlapping interval, both guaranteed the continuity of signal in the right passage, eliminated again the overlapping phenomenon of signal in the right passage.

Current maximal correlation in conjunction with right passage postpones the right channel signal after the extension process

For:

${\hat{R}}_c\left(n\right)=\left\{\begin{array}{cc}\hat{R}e& n<K*(D_{\mathrm{rmp}}-D_{\mathrm{rmc}})\\ R(n-D_{\mathrm{rmc}})& n\&GreaterEqual;K*(D_{\mathrm{rmp}}-D_{\mathrm{rmc}})\end{array}\right.$

A sampled point in above-mentioned certain Frame of above-mentioned n representative, (K) * (D _Rmc-D _Rmp) represent the value of the designated length after the extension process,

Represent the signal of the designated length after the extension process.

Right channel signal after above-mentioned compression or the extension process

What become under different delays is relatively level and smooth, according to above-mentioned

The continuous single channel signal that generates is: $M\left(n\right)=(L\left(n\right)+{\hat{R}}_c\left(n\right))/2.$

1, works as D _Rmp＞D _RmcThe time, above-mentioned designated length is (K-1) * (D _Rmp-D _Rmc), and,

${\hat{R}}_c\left(n\right)=\left\{\begin{array}{cc}\hat{R}e& n<(K-1)*(D_{\mathrm{rmp}}-D_{\mathrm{rmc}})\\ R(n-D_{\mathrm{rmc}})& n\&GreaterEqual;(K-1)*(D_{\mathrm{rmp}}-D_{\mathrm{rmc}})\end{array}\right.$

Therefore, the computing formula of above-mentioned M (n) can be converted into:

$M\left(n\right)=(L\left(n\right)+\hat{R}\left(n\right))/2$ 0＜n＜(K-1)*(D _rmp-D _rmc)

Namely in above-mentioned designated length, with the signal of the designated length after the processing of the compression in the right passage Carry out direct addition with the respective signal in the left passage.

M (n)=(L (n)+R (n-D _Mc))/2 (K-1) * (D _RmP-D _Rmc)＜n＜N N is the length of Frame

Namely outside above-mentioned designated length, with the interchannel correlation delay D of the original signal R in the right passage (n) according to present frame _McAfter postponing, and the respective signal in the left passage is carried out addition.

In this case, the continuous single channel signal of generation as shown in Figure 5.

2, work as D _Rmp＜D _RmcThe time, above-mentioned designated length is K* (D _Rmc-D _Rmp), and,

${\hat{R}}_c\left(n\right)=\left\{\begin{array}{cc}\hat{R}e& n<K*(D_{\mathrm{mc}}-D_{\mathrm{rmp}})\\ R(n-D_{\mathrm{rmc}})& n\&GreaterEqual;K*(D_{\mathrm{rmc}}-D_{\mathrm{rmp}})\end{array}\right.$

Therefore, the computing formula of above-mentioned M (n) can be converted into:

$M\left(n\right)=(L\left(n\right)+\hat{R}\left(n\right))/2$ 0＜n＜K*(D _rmc-D _rmp)

Namely in above-mentioned designated length, with the signal of the designated length after the extension process in the right passage

Carry out direct addition with the respective signal in the left passage.

M (n)=(L (n)+R (n-D _Mc))/2 K* (D _Rmc-D _RmP)＜n＜NN is the length of Frame

Namely outside above-mentioned designated length, with the interchannel correlation delay D of the original signal R in the right passage (n) according to present frame _McAfter postponing, and the respective signal in the left passage is carried out addition.

A concrete application example of the described method of the embodiment of the invention is described below.

Signal for the L channel of m frame is L (n), and the signal of R channel is R (n).The maximum length of the association of left and right acoustic channels simple crosscorrelation is 16, asks the related function of the relatively left passage of right passage to be:

$r_{\mathrm{rl}}\left(m\right)=\underset{n=0}{\overset{15}{\mathrm{\&Sigma;}}}L\left(n\right)R(n-m)$

The linear weighting function that successively decreases is: w (n)=(16-n)/16,0≤n＜16, and the related function of the relatively left passage of right passage after weighting is processed is:

r _rlw(m)＝r _rl(m)*w(m)

Ask for the r after the above-mentioned weighting _Rlw(m) maximal value, n corresponding to this maximal value is D _Rm, that is: r _Rl(D _Rm)=max (r _Rlw(m)).This D _RmBe the right passage of present frame with respect to the maximal correlation delay of left passage, be assumed to be 9.

Suppose that former frame is that the delay of m-1 frame is 5, the delay 9 of present frame is greater than the delay 5 of former frame.So, will count from the ending of frame on the right passage, length is the signal of (9-5) * 4 expands to (9-5) * 5 by becoming Sampling techniques signal, and namely partial-length is (9-5) * 4, and designated length is (9-5) * 5.To deceive as shown in Figure 6 the signal extension of solid line part and be the signal of black dotted portion.

In the part of interframe, adopt right-channel signals and the direct addition of left channel signals after expanding to generate single channel signal from 0 to (9-5) * 5 parts; For other parts of a frame, obtain single channel signal in conjunction with the delay of the present frame of R channel, the single channel signal computing formula is as follows:

$M\left(n\right)=(L\left(n\right)+\hat{R}\left(n\right))/2$ 0≤n＜(9-5)*5

M(n)＝(L(n)+(n-9))/2 (9-5)*5≤n＜FrameLen。

The structural representation of the generating apparatus of the single-channel signals in double-channel signal coding that the embodiment of the invention provides comprises as shown in Figure 7 such as lower module:

Interchannel correlation delay acquisition module 71 is used for the interchannel related function of described present frame is weighted processing, obtains the maximal value of the related function after weighting is processed, and this maximal value is defined as the interchannel correlation delay of described present frame; Interchannel related function to described former frame is weighted processing, obtains the maximal value of the related function after weighting is processed, and this maximal value is defined as the interchannel correlation delay of described former frame.

Signal adjusting module 72, be used for when the interchannel correlation delay of former frame in the interchannel correlation delay of first passage present frame and the described first passage is inconsistent, the signal of the partial-length that the ending of former frame from described first passage is begun compresses or expands, obtain the signal of designated length, the value of described partial-length and designated length is more than or equal to the difference between the interchannel correlation delay of the interchannel correlation delay of described former frame and described present frame.Comprise: signal compression module 721 and signal extension module 722.

Signal generation module 73, be used for signal and the signal corresponding to the signal with described designated length in the second channel of described first passage designated length are carried out generating single pass signal with computing, after other signal outside the designated length described in the described present frame is postponed according to the interchannel correlation delay of present frame and the respective signal in the second channel carry out generating single pass signal with computing.

Signal compression module 721 in the above-mentioned signal adjusting module, be used for when the interchannel correlation delay of first passage present frame during less than the interchannel correlation delay of former frame, the signal of the partial-length that the ending from described former frame is begun compresses, obtain the signal of designated length, the value of described partial-length is greater than the value of described designated length;

Signal extension module 722 in the above-mentioned signal adjusting module, be used for when the interchannel correlation delay of first passage present frame during greater than the interchannel correlation delay of former frame, the signal of the partial-length that the ending from described former frame is begun is expanded, obtain the signal of designated length, the value of described partial-length is less than the value of described designated length.

The application scenarios synoptic diagram of the generating apparatus of the described single-channel signals in double-channel signal coding of the invention described above embodiment in stereo communication as shown in Figure 8, this device generates single channel signal according to the signal of the L channel that receives and R channel, with this single-channel transmission to core encoder.After core encoder is encoded to the single channel signal that receives, the signal behind the coding is carried out and computing with left channel signals and right-channel signals respectively, respectively left and right acoustic channels is carried out the simple crosscorrelation prediction.The residual signals of the L channel after the prediction processing and R channel is transferred to quantization modules.

In sum, the described method and apparatus of the embodiment of the invention postpones when inconsistent in the interchannel correlativity of front and back frame, by becoming the method for sampling signal is compressed or expands, so that the delay of signal is level and smooth in the interframe variation, thereby guaranteed the continuity of the single channel signal of generation.

The described method and apparatus of the embodiment of the invention adopts the related function of weighting to come that correlativity postpones between estimating channel, thereby has reduced the error of related function, has avoided the variation of the predicted value that the interchannel correlativity postpones too fast.

The above; only for the better embodiment of the present invention, but protection scope of the present invention is not limited to this, anyly is familiar with those skilled in the art in the technical scope that the present invention discloses; the variation that can expect easily or replacement all should be encompassed within protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion with the protection domain of claim.

Claims (8)

1. the generation method of a single-channel signals in double-channel signal coding is characterized in that, comprising:

Interchannel related function to present frame is weighted processing, obtains the maximal value of the related function after weighting is processed, and this maximal value is defined as the interchannel correlation delay of described present frame; Interchannel related function to former frame is weighted processing, obtains the maximal value of the related function after weighting is processed, and this maximal value is defined as the interchannel correlation delay of described former frame;

When the interchannel correlation delay of former frame in the interchannel correlation delay of present frame in the first passage and the described first passage is inconsistent, the signal of the partial-length that the ending of former frame from described first passage is begun compresses or expands, obtain the signal of designated length, the value of described partial-length and designated length is more than or equal to the difference between the interchannel correlation delay of the interchannel correlation delay of described former frame and described present frame;

After the signal of the designated length in the described first passage present frame and signal corresponding to the signal with described designated length in the second channel carried out postponing according to the interchannel correlation delay of present frame with computing and with other signal outside the designated length described in the present frame in the described first passage and the respective signal in the second channel carry out generating single pass signal with computing.

2. the generation method of single-channel signals in double-channel signal coding according to claim 1 is characterized in that, described weighting is processed according to weighting function and implemented, and described weighting function comprises the function of linear decrease.

3. the generation method of single-channel signals in double-channel signal coding according to claim 1 is characterized in that, compresses or expands by the signal of the change method of sampling to described partial-length.

4. the generation method of single-channel signals in double-channel signal coding according to claim 3 is characterized in that, the described change method of sampling comprises the Band-limited interpolation method.

5. according to claim 1 to the generation method of 4 each described single-channel signals in double-channel signal coding, it is characterized in that, described interchannel correlation delay and the interchannel correlation delay of former frame when inconsistent when present frame in the first passage, the signal of the partial-length that the ending from described former frame is begun compresses or expands, obtain the signal of designated length, specifically comprise:

When the interchannel correlation delay of present frame in the first passage during less than the interchannel correlation delay of former frame, the signal of the partial-length that the ending from described former frame is begun compresses, obtain the signal of designated length, the value of described partial-length is greater than the value of described designated length;

When the interchannel correlation delay of present frame in the first passage during greater than the interchannel correlation delay of former frame, the signal of the partial-length that the ending from described former frame is begun is expanded, obtain the signal of designated length, the value of described partial-length is less than the value of described designated length.

6. according to claim 1 to the generation method of 4 each described single-channel signals in double-channel signal coding, it is characterized in that described dual-channel audio coding comprises the binary channels stereo audio coding.

7. the generating apparatus of a single-channel signals in double-channel signal coding is characterized in that, comprising:

Interchannel correlation delay acquisition module is used for the interchannel related function of present frame is weighted processing, obtains the maximal value of the related function after weighting is processed, and this maximal value is defined as the interchannel correlation delay of described present frame; Interchannel related function to former frame is weighted processing, obtains the maximal value of the related function after weighting is processed, and this maximal value is defined as the interchannel correlation delay of described former frame;

Signal adjusting module, be used for when the interchannel correlation delay of former frame in the interchannel correlation delay of first passage present frame and the described first passage is inconsistent, the signal of the partial-length that the ending of former frame from described first passage is begun compresses or expands, obtain the signal of designated length, the value of described partial-length and designated length is more than or equal to the difference between the interchannel correlation delay of the interchannel correlation delay of described former frame and described present frame;

The signal generation module, be used for signal and the signal corresponding to the signal with described designated length in the second channel of the designated length of described first passage present frame are carried out generating single pass signal with computing, after other signal outside the designated length described in the described present frame is postponed according to the interchannel correlation delay of present frame and the respective signal in the second channel carry out generating single pass signal with computing.

8. the generating apparatus of single-channel signals in double-channel signal coding according to claim 7 is characterized in that, described signal adjusting module comprises:

The signal compression module, be used for when the interchannel correlation delay of first passage present frame during less than the interchannel correlation delay of former frame, the signal of the partial-length that the ending from described former frame is begun compresses, obtain the signal of designated length, the value of described partial-length is greater than the value of described designated length;

The signal extension module, be used for when the interchannel correlation delay of first passage present frame during greater than the interchannel correlation delay of former frame, the signal of the partial-length that the ending from described former frame is begun is expanded, obtain the signal of designated length, the value of described partial-length is less than the value of described designated length.

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