我要编程软件降噪实时，同样的道理也发生在耳机与主动降噪。是否有任何公开的算法，或者至少，科学对此文件？谷歌搜索发现，关于唯一的非实时降噪信息。

I want to program software for noise canceling in real time, the same way it happens in earphones with active noise canceling. Are there any open algorithms or, at least, science papers about it? A Google search found info about non-realtime noise reduction only.

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主动降噪耳机之外的所有普通耳机的电路，有一个麦克风和额外的特殊电路。在基础层面上的耳机话筒拿起你周围的环境噪音，并将其转发到专用电路。分的声音和模仿它的特殊的电路除$ P $的逆（对面）的方式。逆声音它产生通过耳机扬声器发出并抵消了周围的环境噪音。的

这一切是基于声波的干扰。当2波相位相反的地干扰的结果是没有任何声音。 （它与光的作品了。）

All this is based on sound waves interference. When 2 waves of opposite phases interfer the result is no sound. (it works with light too.)

您应该看一看在波的干扰的维基百科页面找到你需要合适的阶段生产取消外界噪音

You should have a look at the wikipedia page on waves interference to find the right phase you need to produce to cancel the outside noise

对于正弦系统：

让我们以2波：

和

我们希望前preSS所产生的波为：

We want to express the resulting wave as :

由于A1，使得 A0 = 0

这意味着给PHI1你需要找到PHI2，使得A0 = 0

It means given Phi1 you need to find Phi2 such that A0=0

您可以证明：

和解决A0 = 0，你会得到你需要创建取消噪声波频。 这就是所谓的破坏性的干扰。

And solving A0 = 0 you will get the frequence of the wave you need to create to cancel the noise. It's called destructive interferences.

声波不在1维...所以你只会得到相消干涉的一个方向：

Sound waves are not in 1 dimension... so you will just get the destructive interference in one direction:

现在，你只需要找到声音信号的一些东西......

Now you just need to find some stuff of sound signals...

我会尽量回答您的评论。

I will try to answer your comment.

第一：

一个2D问题是不是更困难的一维。

A 2D problem is not much more difficult that the 1D.

该outsoide噪声可以近似为坐落在无穷的源泉。 您将创建一个破坏性的噪声在耳机的来源，并且你可以假设的幅度是一样的，在源距离相等。

The outsoide noise can be approximate as a source situated at the infinity. You will create a destructive noise with a source in your headphones, and you can assume that the amplitude is the same at equal distance of the source .

您需要把它写下来的斧头，Y轴（也可以是很好用极坐标）

You need to write that down on a x,y axis (it can be good to use polar coordinates)

，你将能够获得的幅度上使用简单三角函数公式像是在计划中的每个点：

and you will be able to get the amplitude on each point on the plan using simple trigonometry formulas like :

：\罪（A + B）= \罪A \ CDOT \ COS B + \余弦A \ CDOT \罪乙

:\sin (A + B) = \sin A \cdot \cos B + \cos A \cdot \sin B

：\ COS（A + B）= \ COS A \ CDOT \ COS乙 - \罪A \ CDOT \罪乙

:\cos (A + B) = \cos A \cdot \cos B - \sin A \cdot \sin B

：\罪（A - B）= \罪A \ CDOT \ COS乙 - \ COS A \ CDOT \罪乙

:\sin (A - B) = \sin A \cdot \cos B - \cos A \cdot \sin B

：\ COS（A - B）= \ COS A \ CDOT \ COS B + \罪A \ CDOT \罪乙

:\cos (A - B) = \cos A \cdot \cos B + \sin A \cdot \sin B

二：

所有的延迟modelised在披你破坏源。可刚适应了计算的披所以需要延迟考虑在内。

All the delays are modelised in the "Phi" of your destructive source. Can just Adapt the Calculated Phi so it takes the delay into account.

您可能需要健全的更具体的信息，因为我的信息是非常对单位理论的任何类型的波。

You may need more specific information on sound since my information is very theoric on any types of waves.