transparant color

[Stijn Goris]

hi all,

Is to determine a transparant color in a gif (or ther format). I know gif is
handling a tranparency of 100% but is it also possible to make a pixel let's
say 50% transparant?

I want to make a picture with curly edges and therefore need some
anti-aliasing. I want the background color to change on some events. Giving
me this sort of control over the transparency would alow me to only make on
picture and spare me the work of creating one for each background.

kind regards
Stijn

 

[brucie]

Is to determine a transparant color in a gif (or ther format). I know gif is
handling a tranparency of 100% but is it also possible to make a pixel let's
say 50% transparant?

no. png images have that ability. IE sucks.

test page:
http://www.libpng.org/pub/png/pngsuite.html

 

[Spartanicus]

Is to determine a transparant color in a gif (or ther format). I know gif is
handling a tranparency of 100% but is it also possible to make a pixel let's
say 50% transparant?

With the gif format you can designate one colour out of a palette of max
256 colours to be rendered transparent.

What you'd need is alpha transparency, png files support that, but note
that IE (any version) does not support png alpha transparency.

 

[badstyle]

hi all,

Is to determine a transparant color in a gif (or ther format). I know gif is
handling a tranparency of 100% but is it also possible to make a pixel let's
say 50% transparant?

I want to make a picture with curly edges and therefore need some
anti-aliasing. I want the background color to change on some events. Giving
me this sort of control over the transparency would alow me to only make on
picture and spare me the work of creating one for each background.

kind regards
Stijn

because of IE being really bad - you can account for this but your bg
colour/image has to be a solid colour or a very subtle gradient.

in photoshop [dunno about any other app] when outputting a GIF set the matte
to be a colour nearest to your sites BG colour. It then accounts for that
colour in the aliasing within the image and gives a solid on/off
transparency.


...b..

 

[Toby A Inkster]

What you'd need is alpha transparency, png files support that, but note
that IE (any version) does not support png alpha transparency.

Not strictly true. IE5/Mac supports alpha transparency on PNG files unless
they are used as a background. And there are various ActiveX hacks to
persuade IE5.5+/Win to do alpha transparency with PNG.

 

[Nick Howes]

Not strictly true. IE5/Mac supports alpha transparency on PNG files unless
they are used as a background. And there are various ActiveX hacks to
persuade IE5.5+/Win to do alpha transparency with PNG.

http://www.mijnkopthee.nl has PNG logos with alpha transparency, which works
in IE6/Win. I haven't looked at his source very hard but it seems to just be
stuck in there without faffery. Does this render OK in any older IE's?
Incidentally if you're looking for a good PHP weblog, the author of the
website wrote Pivot (pivotlog.net). I don't get commission, it's just a good
program!

 

[kchayka]

http://www.mijnkopthee.nl has PNG logos with alpha transparency, which works
in IE6/Win.

Not on my box, it doesn't (IE6/W2K). The masthead images are random. I
reloaded the page several times and none of the transparent backgrounds
"worked" at all in IE6.

 

[brucie]

Not on my box, it doesn't (IE6/W2K).

same XP. the images are way too huge anyway.

 

[Marc Nadeau]

Toby A Inkster a écrit:

Not strictly true. IE5/Mac supports alpha transparency on PNG files unless
they are used as a background. And there are various ActiveX hacks to
persuade IE5.5+/Win to do alpha transparency with PNG.

Maybe...

But when i design a website, i want it to be seen correctly in most (if not
all) browsers.

Not only in browsers hacked to work properly.

Most people do not do that.

IE sucks.

Marc Nadeau
http://www.pagerie.com

 

[Toby A Inkster]

Toby A Inkster a écrit:


But when i design a website, i want it to be seen correctly in most (if
not all) browsers. Not only in browsers hacked to work properly. Most
people do not do that.

Most people don't *need* to do that! The *author* adds the ActiveX hacks
to the page: not the visitor.

This means that (with the ActiveX stuff on your page) your translucent PNG
can be seen by anyone using:

Opera 5+ for Windows [1]
Opera 6+ for other platforms [1]
Mozilla for any platform
Netscape 6+ for any platform
Internet Explorer 5+ for Mac
Internet Explorer 5.5+ for Windows
Safari
Konqueror 2+ for any platform [2]
and maybe some other browsers too

That should cover about 90% to 95% of visitors for most sites.

[1] I'm pretty sure that Opera 5 for Linux didn't support alpha on PNGs,
but on Windows it did. Don't have the patience to test my theory though.

[2] Perhaps earlier too. I don't know -- never been a Konq fan.