Help in Mini Project related to Signal Processing

Hi. I am planning to do a mini project on digital signal processing.
currently doing my 3rd year b-tech.
(I have finished a course on DSP and Image processing also)
any ideas are welcome.
Thanks

Simulate the cochlea by creating a filterbank.

Thank you for your reply.
May i know how to start it, and what exactly am i supposed to do in this?

Hi venkatsr,
You can write a code in matlab to decode Mp3 files. It will give you nice exposure in algorthim and programming skills

vinoth8051 said:

Hi venkatsr,
You can write a code in matlab to decode Mp3 files. It will give you nice exposure in algorthim and programming skills

Click to expand...

sorry once again, but pls give a way to start proceedings, i actually didn't get you as to what you mean by decoding of mp3 files.
can you briefly explain as to what exactly to do.

Well apparently, the operation of the cochlea closely resembles that of a filterbank. So all you really have to do is code an analysis filterbank and a synthesis filterbank for an arbitrary audio signal. It would be a trivial project if you use the SP Matlab toolbox, but if you code it by hand from basic operations I think it could be challenging and educational, depending on your knowledge level. This was one of many projects I had for homework in one of my fourth year DSP courses.

How difficult of a project are you looking for?

Hi
Sugestion is to Develop a programme in Matlab (or the language you wish to develop skill C, VB, LabVIEW etc) which will do the following things..
1) Get the MP3 file from user
2) Decode the MP3 file
3) Drive the speaker

For decoding MP3 file, Strong understanding of file format is needed

MPEG-1 or MPEG-2 Audio Layer 3 (or III), more commonly referred to as MP3, is a patented digital audio encoding format using a form of lossy data compression. It is a common audio format for consumer audio storage, as well as a de facto standard of digital audio compression for the transfer and playback of music on digital audio players.

Two standards are governing the MP3 standards
MPEG Version 2 (ISO/IEC 13818-3)
MPEG Version 1 (ISO/IEC 11172-3)
This link MP3 - Wikipedia, the free encyclopedia has some basic information to understanding about file structure, you may wish to refer this also MP3 File Structure [HowTo]

coming to the programming part refer official website for mp3 MP3'Tech - www.mp3-tech.org (check "programmer's section" )

codes are available in Mathworks (Matlab's official website). Temptation will be there to check. But my suggestion will be to "try to develop your own code and compare with the codes available there)

once MP3 file has been decoded you may wisht to do
1) Zero crossing rate
2) Average energy
3) Auto correlation
4) power spectrum analysis
5) Fourier transform

Hope this helps you...

Thank you, both. for your suggestions
now that i know what exactly it is, i guess i 'll start with them, one at a time.

Did you know the mp3 technology exploits the psychoacoustic property known as masking? Interesting stuff.
The idea is that a quite noise will go unnoticed if a louder noise occurs at the same time, in the same frequency band. Mp3 utilizes this by cramming noise underneath the signal. When the spectrum of the signal changes, the noise follows it and hides right underneath it.

here is a good code for audio compression in MATLAB using DCT
Technology World: AUDIO COMPRESSION IN MATLAB