noise cancellation..

[richnabua]

Hello po! pwede po ba magtanong...

how does noise cancellation using DSP works?
what are the limitations of DSP?

[rdpzycho]

galing sa blog ni sir zerowing.

http://geekzone.freehostia.com/noise-cancelling-dsp-algorithm-using-scilab/

paanong limitations? nung hardware? nung algorithm?

[richnabua]

salamat po sa link... nabasa ko na po kaso di ko masyadong naiintindihan...
di po kasi ako engr. student eh
feasibility study po kasi ang sa amin..

pwede po ba paki explain kung paano na wo-work ang noise canceller? yung madali lang maiintindihan ng mga katulad ko na BS Accounting student

 

[rdpzycho]

halimbawa, meron kang ini-interview pero merong mga sasakyan na dumadaan. ang ginagawa ng noise cancellation e kinukuha 'yung sound nung background ('yung mga dumadaan) at isu-subtract doon sa sound. mawawala ngayon 'yung background na sound.

[richnabua]

may nabasa po me about noise cancelling headphones...

totoo po ba na di nito ma cancel out completely ang noise signal? ma reduce lang po dba?

yung noise cancelling headphones pwede po ba yan iconnect sa mobile phones para ma reduce ang noise signal when making a call in a noisy environment? 

[rdpzycho]

hindi mo siya magagamit exactly as is. sa headphone kasi 2 ang independent sound source mo, isa 'yung player, isa 'yung background noise. kaya kukuha lang ng background noise tapos ipla-play lang siya inverted added sa sounds ng player.

yup, 'di talaga completely maca-cancel ang noise.

kung gagamitin sa cellphone, isa lang ang sound source mo, 'yung speaker + noise, nasa iisang microphone. kaya kailangan pag-hiwalayin sa program.

[richnabua]

sir pwede humingi ng image ng:

a.) noise signal  w/o noise canceling DSP

b.) noise signal w/ noise canceling DSP

OR

c.) schematic diagram on how noise reduction using DSP works

[zer0w1ng]

Noise cancelling with a reference noise signal is easier to process than the single microphone.
This could just be processed on time-domain using adaptive filters such as LMS (least mean squares) or better RLS (Recursive least squares).
http://en.wikipedia.org/wiki/Adaptive_filter

I will try to discuss this also in my DSP tutorial in the future.

[richnabua]

sir zer0w1ng help po.. pwede humingi ng image ng:

a.) noise signal  w/o noise canceling DSP

b.) noise signal w/ noise canceling DSP

pls help po para sa feasibility study namin

[zer0w1ng]

Image? Pictures lang?
Try http://images.google.com then type "noise cancellation" on the search box.