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listening tests help, for an audio codec I developed
legg
post Jun 18 2005, 19:51
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How can I rate how good or bad will the audio codec be on average?

I'm thinking on doing at least 21 ABX trials on each file and if the subject managed to tell a difference and the guess probability is low I'd also take into account a 1-5 point scale to measure the perceived quality.

So far I have analized one subject, he did pretty well on most tests, except one, where the results where these:
15 out of 29, pval = 0.500

AFAIK, p<0.05 is good to be certain that he didn't know by chance, what about the rest?
How do I interpret that?, is the codec transparent for him at that test?
What are the ranges of the guess probabilities and how should I interpret them?

Thanks in advance.

This post has been edited by Luis G: Jun 18 2005, 19:52


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legg
post Jun 20 2005, 01:52
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ff123, currently I'm using 8 samples: castanets, finger snaps, french horns, timpani, triangle, trumpets 1, trumpets 2, violins 1 and violins 2. I'm also planning to put male and female voice samples, perhaps a rock/pop/jazz test would also be included. How many subjects should I use to get a significant result?

guruboolez, is a transform codec (MDCT) with 25 bands corresponding to each Bark. The data rate is variable and is always adjusted according to signal demands to achieve good quality. Expected data rates range from 60 to 340kbps.


Greetings.

This post has been edited by Luis G: Jun 20 2005, 01:52


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