"Removing" the background

[AlfredoT]

Hello.

I apologize for my English.
I cannot find how to "remove" the background from a picture.
For instance, this very picture http://it.wikipedia.org/wiki/File:Genova-Stemma.png.
I saved it in jpg, then pasted on a colored background.
My problem is to turn the white background into transparen, I guess.
Can anybody help, please?

Thank you!

[Antonio]

JPEG don't support transparency !!!

Only PNG or GIF support transparency

[AlfredoT]

OIC! did not know that

1. HOW can I use transparency on a png? I do not know the steps!
2. can I use transparency on a PNG and, after, convert it into jpg maintaining transparency?

Grazie Antonio

[AlfredoT]

Anybody can help, please?

[Antonio]

can I use transparency on a PNG and, after, convert it into jpg maintaining transparency?
==> some confusion because i tell you that jpeg don't maintain transparency.

Perhaps you can try to find some sites in the web talking about transparency image format to understand better

I can not explain you correctelly because i don't speak english very well

[AlfredoT]

No. Using the term "maintain" I understood!
I thought in could not be done on it!

Thank you!