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Author Topic: Is there an audio filter to remove vuvuzelas from footie broadcast audio?  (Read 9261 times)

Offline syhprum

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Vuvuzola,s make the viewing of the world cup football a misery, they broadly peak at 233 and 466Hz are there any freely available software filters that might be used to reduce them.
« Last Edit: 20/06/2010 23:16:30 by chris »


 

Offline RD

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« Last Edit: 19/06/2010 21:27:32 by RD »
 

Offline syhprum

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Thanks RD

If you want to test and adjust your filter the continuous sound of vuvuzelas is available here

http://www.vuvuzela.fm/
 

Offline SeanB

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I am 5km from the stadium, and you can hear them on match days quite easily.

 

Offline RD

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I've just had a look at the vuvuzela spectrum using Audacity



You'd have to notch out the fundamental (236Hz) and then at least next 6 harmonics to remove most of it.

(These are the main peaks on the graph).

If anyone in the crowd has an off-key vuvuzela it would get past such a notch filter.
« Last Edit: 20/06/2010 14:23:40 by RD »
 

Offline syhprum

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Here are Audacity analysis of the transmissions of vuvuzela FM with and without filter.
It it is only simple to include the filter in the sound channel if you have a separate set top box with sound output terminals feeding the TV if you have a modern TV with no external gadgets it becomes more difficult.
One should bear in mind that there are normally stereo outputs from the set top box the best results will be had if these are combined and the derived mono signal fed thru the filter to both channels on the TV.

« Last Edit: 20/06/2010 15:51:24 by syhprum »
 

Offline RD

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You need to use the highest sample "size" possible to see the peaks ...



Here the maximum size of 16384 was selected (and a logarithmic horizontal scale).
« Last Edit: 20/06/2010 15:48:21 by RD »
 

Offline Geezer

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Couldn't you just turn off the sound and play some funereal background music, or a loop of random crowd noises instead?

Is the commentary really that good (isn't it usually a load of piffle anyway?)
 

Offline tommya300

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Real-time anti noise with DSP "digital signal processing" idea.

This is just an example for the idea applied

http://www.cdxetextbook.com/fuelSys/intakeExhaust/exComp/electronicmufflers.html
 

Offline nicephotog

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Most movie players come with graphic equalisers for audio, and can be configured for streaming TV. Unless its part of the broadcast service, why not use one e.g. VLC media player and adjust to vuvuzela tastes?
 

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