A-weighting filter to lookup table
조회 수: 5 (최근 30일)
이전 댓글 표시
hello,
i'm working at an embedded SPL meter, it has to filter out the audio using A-weighting.
I've build a script to test A-weighting filters, but here comes the problem.
My idea is to build a lookup table, that contains the weight value for a specific frequency, then use this table to weighting the signal using fft.
I'm investigating three filters, one build upong the fdesign function, one two using filter coefficients based functions.
I've two question and one problem:
1) is my method correct?
2) what filter table i've to use? if i test it seems that the two coef based filters differs from an offset.
download sample code here: https://www.dropbox.com/s/62ueiv3rmc8l3tc/test.zip
thank you!
댓글 수: 1
Daniel Shub
2014년 1월 8일
It is not clear what you are doing, what you are getting, and what you expect. Without this information, it is hard to answer your question.
답변 (4개)
Wayne King
2014년 1월 2일
How about using
fdesign.audioweighting
if you have the DSP System Toolbox? That will give you A-weighting.
댓글 수: 0
Al Hasan
2014년 1월 2일
Hey Davide,
Was your method correct ?
I have attached an image is that A weighted filtering
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/174164/image.png)
By any chance do you know what they are doing to the above image to get the below image in my attachment, I have data to make the above image dunno how to make the below one from the above
Thanks, Hasan
댓글 수: 0
Davide
2014년 1월 11일
댓글 수: 1
Daniel Shub
2014년 1월 16일
Okay, and what happens when you run the code? What are you expecting to happen? What would you like to happen? Ideally you should strip the code down to be as minimal as possible. Right now it looks like it should plot 3 figures. If those figures are not related to the problem, don't post that part of the code. You right to an xls file, presumably this isn't the problem. The simpiler the code, the more easily we can help you.
참고 항목
카테고리
Help Center 및 File Exchange에서 Filter Analysis에 대해 자세히 알아보기
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!