There is a script for very fast interactive image resizing using isotropic nearest neighbor sampling.
http://www.jsoftware.com/jwiki/Scripts/Zoom_View > From: David Vincent-Jones <[EMAIL PROTECTED]> > > Yes ... I want to sample every 10th. pixel, not a full resolution sample > block. > > David > > On Wed, 2008-09-10 at 22:19 +1200, Sherlock, Ric wrote: > > ---David Vincent-Jones wrote: > > > Digital images are getting to be very large today so some specialized > > > processes become very lengthy. Sometimes I need to test > > > several sets of > > > parameters and at full resolution it can be very tedious. > > > > > > Can somebody suggest a way to subset working something like this: > > > > > > $ bigimage > > > 5000 4000 3 > > > sub10=: 10 subset bigimage > > > > > > $ subimage > > > 500 400 3 > > > > Can you confirm that you want to sample every 10th pixel rather than take a > 500 by 400 pixel region from the original? > > > > If so then this might work? > > > > subset=: 3 : 0 > > 10 subset y > > : > > idx=. x&[EMAIL PROTECTED] x %~ 2{.$y > > ( > > ) > > > > tst=: i. 50 40 3 > > > > $10 subset tst > > 5 4 3 > > > > 10 subset tst > > 0 1 2 > > 30 31 32 > > 60 61 62 > > 90 91 92 > > > > 1200 1201 1202 > > 1230 1231 1232 > > 1260 1261 1262 > > 1290 1291 1292 > > > > 2400 2401 2402 > > 2430 2431 2432 > > 2460 2461 2462 > > 2490 2491 2492 > > > > 3600 3601 3602 > > 3630 3631 3632 > > 3660 3661 3662 > > 3690 3691 3692 > > > > 4800 4801 4802 > > 4830 4831 4832 > > 4860 4861 4862 > > 4890 4891 4892 > > ---------------------------------------------------------------------- > > For information about J forums see http://www.jsoftware.com/forums.htm > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
