why arepairs of damaged audio restricted to 128 samples max?

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jerome42
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why arepairs of damaged audio restricted to 128 samples max?

Post by jerome42 » Sat Jan 12, 2013 11:56 am

In repair.cpp -> EffectRepair::Process() the repairLen is restricted to a maximum of 128 samples.

The applied Least Squares AutoRegressive Interpolation method imposes no theoretical maximum.

So does anybody know where else this maximum stems from and why a power of 2?

Thanks, jerome42

Gale Andrews
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Re: why arepairs of damaged audio restricted to 128 samples

Post by Gale Andrews » Sat Jan 12, 2013 2:19 pm

jerome42 wrote:In repair.cpp -> EffectRepair::Process() the repairLen is restricted to a maximum of 128 samples.
Change it to for example 512 samples and see how long Repair takes then.


Gale
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jerome42
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Re: why arepairs of damaged audio restricted to 128 samples

Post by jerome42 » Sat Jan 12, 2013 8:09 pm

Gale Andrews wrote:
jerome42 wrote:In repair.cpp -> EffectRepair::Process() the repairLen is restricted to a maximum of 128 samples.
Change it to for example 512 samples and see how long Repair takes then.


Gale
OK, Gale, so there is an almost cubic relation between repairlen and processing time, due to the use of matrices.
However there is no need to restrict the repairlen to a value being a power of 2: e.g. 200 would do also!

Jerome42

steve
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Re: why arepairs of damaged audio restricted to 128 samples

Post by steve » Mon Jan 14, 2013 4:44 am

jerome42 wrote: OK, Gale, so there is an almost cubic relation between repairlen and processing time, due to the use of matrices.
However there is no need to restrict the repairlen to a value being a power of 2: e.g. 200 would do also!
If the relationship is cubic, then increasing the number of samples from 128 to 200 would be what? About 4 times longer processing time?
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Robert J. H.
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Re: why arepairs of damaged audio restricted to 128 samples

Post by Robert J. H. » Mon Jan 14, 2013 7:41 am

Very good guess, It is 3.8147, if it is really cubic.

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