Re: Rendering quality (subsampling)

FWIW, my experience is that regrettably, the HW/OS combo is key to the
image rendering quality; I had a servlet app I developed on Mac OS X
that produced SVG images on demand that had to be returned to the Web
client as PNG. On the Mac, the rendering was extremely good, but when
run on a PC/Linux server, it produced unacceptable images. In our
case, this issue was mostly that of poor text rendering at small type
sizes, due to bad anti-aliasing. After a lot of testing, we decided to
get a Mac dedicated to image rendering!   YMMV.
best
Martin

On 14 December 2011 16:01, Steve Maher <[email protected]> wrote:
> Hi,
>
> I'm looking for a high-quality SVG renderer.  Batik's rasterizer seems to be
> the best out of the three I've tried, but I need it to do better.  I've
> tried all the image-rendering, shape-rendering, color-rendering hints
> without much (any?) change.  I've searched the source - mainly to try to
> increase any subsampling quantities - but had no luck.
>
> I'm dealing with small circles that need to be rendered "correctly" for a
> custom projector in our lab at work.
>
> For example, for a circle of radius .5 pixels (no stroke), and centered in
> the middle of a pixel (in other words, a circle touching the edges of a
> pixel), the rendered pixel intensity should be roughly PI/4 times the
> intensity of the circle (because the ratio of circle area to square area is
> PI/4).
>
> Also, if I rotate the circle by 45 degrees (rotation centered on corner of
> pixel), there will be a 4 pixel square used to render the circle, with most
> intensity split between two adjacent pixels and much less intensity split
> between the other two adjacent pixels.
>
> Batik comes close, but the intensity is high in the first case and in the
> second case, the intensity is not symmetric between the adjacent pixels
> (like the rotation wasn't exactly 45 degrees).
>
> One option I am exploring is to artificially enlarge the scene, render by 1
> pixel circle across, oh, 100 pixels, and then shrink the image.  Effectively
> increasing the subsampling of the circle to determine pixel intensity.  I
> was hoping to be able to do that natively in the Batik source - or use some
> other SVG renderer.
>
> Any tips are appreciated -
>
> Regards,
> Steve
>
>



-- 
From my MacBook Pro