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Groups > comp.lang.c > #384376

Re: filling area by color atack safety - worst memory size

From Michael S <already5chosen@yahoo.com>
Newsgroups comp.lang.c
Subject Re: filling area by color atack safety - worst memory size
Date 2024-04-20 21:10 +0300
Organization A noiseless patient Spider
Message-ID <20240420211023.000067cc@yahoo.com> (permalink)
References (12 earlier) <86bk6ez9te.fsf@linuxsc.com> <20240417004609.000010aa@yahoo.com> <86plunyj82.fsf@linuxsc.com> <20240417224126.0000727a@yahoo.com> <86a5lpxbd3.fsf@linuxsc.com>

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On Fri, 19 Apr 2024 14:59:20 -0700
Tim Rentsch <tr.17687@z991.linuxsc.com> wrote:

> Michael S <already5chosen@yahoo.com> writes:
> 
> > On Wed, 17 Apr 2024 10:47:25 -0700
> > Tim Rentsch <tr.17687@z991.linuxsc.com> wrote:
> >  
> >> Michael S <already5chosen@yahoo.com> writes:
> >>
> >> [...]
> >>  
> >>> Finally found the time for speed measurements.  [...]  
> >>
> >> I got these.  Thank you.
> >>
> >> The format used didn't make it easy to do any automated
> >> processing.  I was able to get around that, although it
> >> would have been nicer if that had been easier.
> >>
> >> The results you got are radically different than my own,
> >> to the point where I wonder if there is something else
> >> going on.  
> >
> > What are your absolute result?
> > Are they much faster, much slower or similar to mine?
> > Also it would help if you find out characteristics of your
> > test hardware.  
> 
> I think trying to look at those wouldn't tell me anything
> helpful.  Too many unknowns.  And still no way to test or
> measure any changes to the various algorithms.
>

Frankly, I don't understand.
If you have troubles with testing on shared hardware then you can
always test on the hardware that you own and has full control.
Even if it is a little old, the trends tend to be the same. At least I
clearly see the same trends on my almost 12 y.o. home PC and on
relatively modern EPYC3.

> >> Considering that, since I now have no way of doing any
> >> useful measuring, it seems there is little point in any
> >> further development or investigation on my part.  It's
> >> been fun, even if ultimately inconclusive.  
> >
> > I am still interested in combination of speed that does
> > not suck with O(N) worst-case memory footprint.
> > I already have couple of variants of the former,  
> 
> Did you mean you some algorithms whose worst case memory
> behavior is strictly less than O( total number of pixels )?
> 
> I think it would be helpful to adopt a standard terminology
> where the pixel field is of size M x N, otherwise I'm not
> sure what O(N) refers to.
> 

No, I mean O(max(M,N)) plus possibly some logarithmic component that
loses significance when images grow bigger.
More so, if bounding rectangle of the shape is A x B then I'd like
memory requirements to be O(max(A,B)), but so far it does not appear to
be possible, or at least not possible without significant complications
and further slowdown. So, as an intermediate goal I am willing to
accept that allocation would be O(max(M,N)). but amount of touched
memory is O(max(A,B)).

> > but so
> > far they are all unreasonably slow - ~5 times slower than
> > the best.  
> 
> I'm no longer working on the problem but I'm interested to
> hear what you come up with.

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Thread

Re: filling area by color atack safety Michael S <already5chosen@yahoo.com> - 2024-03-24 19:33 +0300
  Re: filling area by color atack safety Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-03-24 10:24 -0700
    Re: filling area by color atack safety Michael S <already5chosen@yahoo.com> - 2024-03-25 01:04 +0300
    Re: filling area by color atack safety - worst memory size Michael S <already5chosen@yahoo.com> - 2024-04-05 17:30 +0300
      Re: filling area by color atack safety - worst memory size Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-04-10 19:47 -0700
        Re: filling area by color atack safety - worst memory size Michael S <already5chosen@yahoo.com> - 2024-04-11 15:20 +0300
          Re: filling area by color atack safety - worst memory size Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-04-11 21:06 -0700
          Re: filling area by color atack safety - worst memory size Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-04-11 21:55 -0700
          Re: filling area by color atack safety - worst memory size Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-04-11 22:09 -0700
            Re: filling area by color atack safety - worst memory size Michael S <already5chosen@yahoo.com> - 2024-04-12 11:13 +0300
              Re: filling area by color atack safety - worst memory size Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-04-13 08:30 -0700
          Re: filling area by color atack safety - worst memory size Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-04-11 22:38 -0700
          Re: filling area by color atack safety - worst memory size Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-04-11 22:43 -0700
          Re: filling area by color atack safety - worst memory size Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-04-12 11:59 -0700
            Re: filling area by color atack safety - worst memory size Michael S <already5chosen@yahoo.com> - 2024-04-13 20:26 +0300
              Re: filling area by color atack safety - worst memory size Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-04-13 10:54 -0700
                Re: filling area by color atack safety - worst memory size Michael S <already5chosen@yahoo.com> - 2024-04-13 23:11 +0300
            Re: filling area by color atack safety - worst memory size Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-04-17 10:47 -0700
              Re: filling area by color atack safety - worst memory size Michael S <already5chosen@yahoo.com> - 2024-04-17 22:41 +0300
                Re: filling area by color atack safety - worst memory size Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-04-19 14:59 -0700
                Re: filling area by color atack safety - worst memory size Michael S <already5chosen@yahoo.com> - 2024-04-20 21:10 +0300
                Re: filling area by color atack safety - worst memory size Michael S <already5chosen@yahoo.com> - 2024-04-25 17:56 +0300
                Re: filling area by color atack safety - worst memory size Michael S <already5chosen@yahoo.com> - 2024-05-03 18:33 +0300
                Re: filling area by color atack safety - worst memory size Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-05-15 09:57 -0700

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