[IPOL discuss] computing and displaying contours

[Juan Cardelino]

On Wed, Mar 16, 2011 at 4:30 AM, Nicolas Limare
<nicolas.limare at cmla.ens-cachan.fr> wrote:
>> In the first place, I would rather use svg as intermediate format, I'm
>> not sure if I'm being a fashion victim here, but SVG seems the way to
>> go.
>
> Then we would be two fashion victims!
> Seriously, SVG has real advantages over EPS: more drawing primitives,
> the support of "filters" (blurring, convolutions, ...) and direct
> inclusion in (X)HTML documents. Maybe PostScipt is more exciting for
> programmers because it's a stack-oriented programming language... but
> these considerations are not relevant for IPOL :)
>
> Rafael chose eps because of the bad visual quality of svg-png
> conversion. I think it's worth a benchmark, vith visual comparisons.
>
>> The second doubt is a particular problem of this case. The 2d kernel
>> to display is sampled on a very coarse grid, which could be around
>> 17x17. this mean that displaying the raster PNG would be rather ugly,
>> however it think we could upsample with interpolation and show a
>> bigger image (like 170x170) image which hopefully will be smooth
>> enough.
>
> I don't understand. If you want to display a vector kernel as a raster
> image, can't you set the rasterization resolution large enough to see
> all the details? How is this 17x17 svg->png conversion different from
> directly including the SVG in the page?
>

I mean, the contour sampled at that resolution, but nothing refrains
me from upsampling and interpolation. In svg I would approximate the
countour with something smooth and represent it as an svg file.


> Best,
>
> --
> Nicolas LIMARE - CMLA - ENS Cachan    http://www.cmla.ens-cachan.fr/~limare/
> IPOL - image processing on line                          http://www.ipol.im/
>
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