Re: image.m and scaling

[avraham]

On Fri, Jun 03, 2005 at 05:59:28PM -0400, Brian Blais wrote:
> Hello,
> 
> I was wondering what others thought of the following observation.  When
> I do an image command, or an imagesc command, the resulting image is
> increased in size (IMHO, good) and smoothed (IMHO, bad).  Usually when I
> am looking at a small matrix, I am looking at data and would like to see
> an honest representation of those data points, more similar to matlab's
> image command.  If one changes one word in image.m from:
> 
> im_display = sprintf ("display -geometry %f%% \"%s\"", zoom*100, ppm_name);
> 
> to:
> 
> im_display = sprintf ("display -sample %f%% \"%s\"", zoom*100, ppm_name);
> 
> using the -sample option, then you get the same increase in size, which
> is good for visibility, and the image is not smoothed.  Try it with:
> 
> imagesc(rand(20));
> 
> and you'll see the difference.  Is this something that others would
> like, or is the present behavior there for some reason?
> 
> 
>                       thanks,
> 
>                               Brian Blais
> 
> 
> -- 
> -----------------
> 
>             address@hidden
>             http://web.bryant.edu/~bblais
> 
> 
> 
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Good Morning,
Thanks for the note. I never noticed that before, maybe because I
usually work with large arrays and only seldom used the zoom
argument. I fully agree with you: The default should be the
faithful representation of the data. If anyone wishes to smooth
the image, let them do it on their own, in precisely defined
conditions. 
Cheers, Avraham



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