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xiaohongwu / aforge

Automatically exported from code.google.com/p/aforge
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Image statistics reports negative mean value for big images #27

Closed GoogleCodeExporter closed 8 years ago

GoogleCodeExporter commented 8 years ago 
In the case of big images (around 4000x3000) images statistics calculates 
incorrect mean value, which is negative.

Original issue reported on code.google.com by andrew.k...@gmail.com on 12 Sep 2007 at 4:43

GoogleCodeExporter commented 8 years ago

Original comment by andrew.k...@gmail.com on 13 Sep 2007 at 4:22

GoogleCodeExporter commented 8 years ago 
AForge.Math.Statistics.Mean() was fixed to use double for mean calculation 
instead 
of int.

SVN revision - 345, will be released in AForge.NET 1.5.0

Original comment by andrew.k...@gmail.com on 13 Sep 2007 at 4:25

GoogleCodeExporter commented 8 years ago

Original comment by andrew.k...@gmail.com on 13 Sep 2007 at 4:27

GoogleCodeExporter commented 8 years ago

Original comment by andrew.k...@gmail.com on 19 May 2008 at 6:08

GoogleCodeExporter commented 8 years ago 
The mean and standard deviation calculations are still incorrect for larger 
images. It seems to work fine for 1024x1024 or less, but I get incorrect values 
for 1280x1024 grayscale images.

Original comment by carrasm...@gmail.com on 18 Jul 2011 at 5:18

GoogleCodeExporter commented 8 years ago 
Problem confirmed with this image.

Original comment by br...@sistemasmart.com.br on 14 Apr 2014 at 1:29

Attachments:

GoogleCodeExporter commented 8 years ago 
Updated calculation of mean in AForge.Math.Statistics to use double precision 
numbers internally to avoid integers' overflow.

Committed in revision 1730.

Original comment by andrew.k...@gmail.com on 23 Apr 2014 at 7:41