ippiResizeSqrPixel problem (64-Bit only)

ippiResizeSqrPixel problem (64-Bit only)

jkj-k-s.com's picture
jkj-k-s.com
Tue, 09/15/2009 - 09:19

the parallel usage of ippiResizeSqrPixel works fine in a 32-Bit program, but has gaps when compiled in 64-Bit and running on more then 2 cores.
here is a VS2008 sample to illustrate the effect: www.j-k-s.com/test/ScaleTest.zip (compile in 32 & 64, and see the difference by scaling the window to force redraw).

any idea what's going wrong?

RSS Top
4 posts / 0 new
Last post
For more complete information about compiler optimizations, see our Optimization Notice.
Yuri Tikhomirov (Intel)'s picture
Yuri Tikhomirov (Intel)
Fri, 09/18/2009 - 00:13

Hello,

Some experiments with VS2008 and VS20010 have shown that the compiler works incorrectly with structures. So different threads process the same piece of image.
There is an error in MS compiler :(

We recommend to use (1st or 2nd or 3rd):

  1. Intel compiler. It works right!
  2. Dynamic or threaded static libraries instead external parallelization with statics. They have parallelized version of resize.
  3. Workaround. To write a wrapper in which structure is replaced on separate variables.

Thanks,
Beg

Top
Yuri Tikhomirov (Intel)'s picture
Yuri Tikhomirov (Intel)
Fri, 09/18/2009 - 00:25
1.small correction(ScaleTest.cpp; line.222)

if(id == nt-1) dr.height -=dr.y;
instead
if(id == nt-1) dr.height = droi.height - droi.y;

2. the last slice can be non whole for any image size

dr.height = droi.height % nt
instead
dr.height = droi.height / nt;

Thanks,
Beg

Top
jkj-k-s.com's picture
jkj-k-s.com
Fri, 09/18/2009 - 04:20
Thanks!

(why am i not surprised? :] )

Top

Login to leave a comment.