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Re: inverse gradient [message #64059 is a reply to message #63980]

Fri, 28 November 2008 08:31

pgrigis
Messages: 436
Registered: September 2007

Senior Member

Jeremy Bailin wrote:
> On Nov 27, 3:27�am, erano <eran.o...@gmail.com> wrote:
>>> "inverse" meaning what for a vector-field?
>>
>>> Paolo
>>
>> "inverse" is the opposite operation for gradient.
>> The inputs are 2D gradient images (dX and dY), where high values are
>> large changes in the "inverse gradient" image, and zeros are stable
>> (no changes) in the "inverse gradient".
>>
>> Eran
>
> I would never use this in production code, but here's a hack that will
> give you something to look at:
>
> scalarfield = total(dX, /cumulative, 1) + total(dY, /cumulative, 2)

From the standpoint of discrete operations, that's perfectly fine.
As an approximation for the real potential, that depends on
how the gradient was measured I gues...

Paolo

>
> The real solution is to replace those totals with actual integrals.
>
> -Jeremy.

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[Message index]

		inverse gradient By: erano on Wed, 26 November 2008 02:10
		Re: inverse gradient By: pgrigis on Tue, 02 December 2008 10:59
		Re: inverse gradient By: erano on Tue, 02 December 2008 11:42
		Re: inverse gradient By: erano on Tue, 02 December 2008 10:50
		Re: inverse gradient By: pgrigis on Tue, 02 December 2008 09:20
		Re: inverse gradient By: erano on Tue, 02 December 2008 09:04
		Re: inverse gradient By: pgrigis on Tue, 02 December 2008 07:45
		Re: inverse gradient By: erano on Tue, 02 December 2008 07:12
		Re: inverse gradient By: pgrigis on Tue, 02 December 2008 06:45
		Re: inverse gradient By: erano on Tue, 02 December 2008 01:27
		Re: inverse gradient By: pgrigis on Fri, 28 November 2008 08:31
		Re: inverse gradient By: pgrigis on Fri, 28 November 2008 08:18
		Re: inverse gradient By: pgrigis on Fri, 28 November 2008 08:14
		Re: inverse gradient By: pgrigis on Fri, 28 November 2008 08:10
		Re: inverse gradient By: Jeremy Bailin on Fri, 28 November 2008 05:27
		Re: inverse gradient By: erano on Fri, 28 November 2008 01:31
		Re: inverse gradient By: Jeremy Bailin on Thu, 27 November 2008 06:24
		Re: inverse gradient By: pgrigis on Tue, 02 December 2008 14:44
		Re: inverse gradient By: erano on Tue, 09 December 2008 00:36
		Re: inverse gradient By: erano on Wed, 24 December 2008 01:55

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