How can i find the centroid of the wavelet coefficients from each frame of the audio signal?

Question

maxina dialin 2012-10-8

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/50149-how-can-i-find-the-centroid-of-the-wavelet-coefficients-from-each-frame-of-the-audio-signal

Hi,i have to find the centroid of the wavelet coefficients for each frame of the audio signal.,i've applied wavedec to decompose the audio into 5 levels CA5,CD1,CD2,CD3,CD4,CD5 from that i have to find the energy and centroid of the wavelet coefficients.Is there anybody know about this?

4 个评论
显示 2更早的评论隐藏 2更早的评论

Walter Roberson 2012-10-8

?? What image is it that you are decomposing ??

maxina dialin 2012-10-9

that is not a image.,actually it is a audio signal.,sry i mentioned that is a image. i applied wavedec for an audio signal.,after that i have to calculate energy and centroid of the wavelet coefficients(approximation and detail)for all frames of the audio signal.,i dnt know how to do.,can u pls help me?

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Wayne King 2012-10-8

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/50149-how-can-i-find-the-centroid-of-the-wavelet-coefficients-from-each-frame-of-the-audio-signal#answer_61278

编辑：Wayne King 2012-10-8

在 MATLAB Online 中打开

You can use wenergy() to find the energy in the output of wavedec()

   load noisdopp;
   [C,L] = wavedec(noisdopp,5,'sym4');
   [Ea,Ed] = wenergy(C,L);

What do you mean by centroid? The mean? You can do that with detcoef() although the mean of the detail coefficients will be close to zero at each level I would suspect.

     details = detcoef(C,L,'cells');
     centroids = cellfun(@mean,details);

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

maxina dialin 2012-10-9

no.,actually i have to find one centroid value for all coefficients., if i use the function what you suggested above means i get 5 values.(since decomposition level is 5) but i want a single centroid value for coefficients including app. and detail coefficients.(ca5,cd1...cd5) how can i do that? the formula which i have to use is sum(i*(x(i)^2))/sum(x(i))^2 where x(i) is the ith wavelet coefficient.i=1,2..6(since we have 6 coefficients ca5,cd1...cd5) do u have any idea about this?

请先登录，再进行评论。