Re: zigzag scan: Image processing function

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Hi Muthiah!

I took the liberty of writing my own quicker version of zigzag.  I've
also added support for mxn matrices (where m!=3Dn).

Code is attached.

Cheers
Fredrik B=FClow

On 10/5/06, Muthiah Annamalai <[email protected]> wrote:
>
>  Hello there,
>  I have a function zigzag() which walks-off a (square)matrix and reads it=
s
> elements in a zigzag fashion. It is useful for image processing.
>
>  Example:
>  octave  --eval
> "x=3D[1:4]'*[1:4];eval('x');tic;printf('%d\n',zigzagscan(x));toc()"
> -q
>  x =3D
>
>      1    2    3    4
>      2    4    6    8
>      3    6    9   12
>      4    8   12   16
>
>  1
>  2
>  2
>  3
>  4
>  3
>  4
>  6
>  6
>  4
>  8
>  9
>  8
>  12
>  12
>  16
>  Elapsed time is 0.177223 seconds.
>
>
>  However I dont know where I should commit it to in Octave-forge.
>  Someone please suggest the right place.
>
>  Code is attached.
>
>  Cheers
>  Muthu
>
>
> _______________________________________________
> Octave-sources mailing list
> [email protected]
> https://www.cae.wisc.edu/mailman/listinfo/octave-sources
>
>
>
>

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