Bizarre anti-aliasing problem

[thrybergh]

Hello.

I have a series of images (sized 100x100 pixels). They are all logos and have a standard shading effect applied to the left hand side of them which makes them appear to "fade" them into the distance. The effect is created by having every other line be a "graded-in" white solid line e.g.

xxxxxxxxxxxxxxxxxxxx
       x xx xxxxxxxx
xxxxxxxxxxxxxxxxxxxx
       x xx xxxxxxxx
xxxxxxxxxxxxxxxxxxxx
       x xx xxxxxxxx
xxxxxxxxxxxxxxxxxxxx
       x xx xxxxxxxx
xxxxxxxxxxxxxxxxxxxx
       x xx xxxxxxxx
xxxxxxxxxxxxxxxxxxxx

I'm using IE 5.0 and when I create a static HTML page my images (scaled down to 50x50) are rendered and the fading from the white lines is effectively "lost" due to the scaling. The logos appear to be made of solid colour. I understand why this is, as if the line of detail is 1 pixel, then it can't be scaled down. This is not a problem.

However things get a little strange when I create the same page via a Java servlet and XSL stylesheet. The anti-aliasing algorithm seems to lose the non-white lines and my logos look like they are only half there! It's not a serious problem but I'd like to know if anyone else has had a similar encounter!

I just don't understand why there are inconsistencies in the anti-aliasing.

 

[theocraticmind]

>>However things get a little strange when I create the same page via a Java servlet and XSL stylesheet.

Maybe another forum?

 

[ChrisHunt]

Hmmm... can't see why this would happen if the generated HTML is the same. Where is the XSL running - on the server or on the browser? Don't know enough about java servelets to offer an opinion.

However, you're taking a risk by assuming that browsers will scale your images in a particular way - if IE5.0 is a bit quirky, imagine what the panoply of other browsers, graphics set-ups and hardware platforms are going to do! If you NEED a 50x50 version of your graphics, better to MAKE a 50x50 version with a graphics program that to leave it to the browser. That way you can be sure they'll look how you want them to, and download quicker too!

-- Chris Hunt
Extra Connections Ltd

http://www.extracon.com

 

[thrybergh]

Thanks for the tips. I think it will be worth making a half-size version of each logo, even though there are 92 of them to do.

That's a valid point about different browsers and platforms. I tend to only cater for IE, through laziness.

 

[TheConeHead]

are these gifs? gifs do not resize well... if you save them as jpgs, you may have better luck and not need two copies

 

[ChrisHirst]

If you want a tool to do batch resizing take a look at IrfanView

http://www.irfanview.com/

Chris.


Indifference will be the downfall of mankind, but who cares?

 

[thrybergh]

I used Fireworks which had a batch converter facility. I'd never seen that before, but it was useful. I made 100% quality JPGs and the page is looking a lot better now thanks.