## Re: [Algorithms] Computing row means of a texture

 Re: [Algorithms] Computing row means of a texture From: Anders Nilsson - 2005-05-30 14:29:17 ```Hm could this be faster: Add the right half of the texture to the left half of the texture (so added[0]=3Dpixel[0]+pixel[128] for a pixel with 256 in width). Then recurse for the left 128 pixels. Pretty soon you should have the row-sums in one column (needs to be float or something to not overflow though, but it seems your texture D should overflow with your algorithm as well so I've guess you've got that covered!). For a row-width of 2^k you need k divisions and they are dependant, ie you need to add from what you are creating. They size of the added texture however halfs each time. Just a thought. Anders Nilsson ```

 [Algorithms] Computing row means of a texture From: Chris Haarmeijer - 2005-05-30 11:40:49 ```Hi, I need to compute the row means of a texture A. The resulting texture D is used to demean texture A. I've currently implemented it in a way that is really slow but works: walk over the columns of texture A, add the values of that column with additive blending to destination texture D. Finally, when demeaning texture A, subtract a value from texture A using texture D divided by the number of columns in texture A. Has anybody tried to implement a demeaning algorithm on the GPU before ? Kind regards, Chris --- Keep IT Simple Software P: P.O.Box 548, 7500 AM Enschede, The Netherlands W: http://www.keepitsimple.nl E: mailto:info@... T: +31 53 4356687 ```
 Re: [Algorithms] Computing row means of a texture From: Ville Miettinen - 2005-05-30 13:20:02 ```> > Has anybody tried to implement a demeaning algorithm on the GPU > before ? > I've implemented a number of algorithms on the GPU although none of them have been particularly demeaning :) cheers, -wili -- Ville Miettinen, CTO Hybrid Graphics, Ltd. http://www.hybrid.fi > Kind regards, > > Chris ```
 Re: [Algorithms] Computing row means of a texture From: Anders Nilsson - 2005-05-30 14:29:17 ```Hm could this be faster: Add the right half of the texture to the left half of the texture (so added[0]=3Dpixel[0]+pixel[128] for a pixel with 256 in width). Then recurse for the left 128 pixels. Pretty soon you should have the row-sums in one column (needs to be float or something to not overflow though, but it seems your texture D should overflow with your algorithm as well so I've guess you've got that covered!). For a row-width of 2^k you need k divisions and they are dependant, ie you need to add from what you are creating. They size of the added texture however halfs each time. Just a thought. Anders Nilsson ```