[Digikam-users] png huge

[Martin Senftleben]

Hi,

with the many replies to my question I still believe I haven't been 
understood properly, even though I am very grateful for the replies 
which helped me to understand things better.

I recall the situation or my question:
from a jpg image file, a png image file is created. The jpg file can 
contain only what is stored in it, right? The compression method is 
lossy, so whatever is stored in there isn't complete already. This is 
also - in my view - proven by the png that results when I transfer the 
jpg file to the png format: they look absolutely alike, the png image 
is in no way better than the "original" jpg image, it's only about 5 
times larger.
The source of the png file is not the original raw image, but the 
lossy compressed jpg file. Is it possible for the png to extract more 
from the jpg file than there is in it? Or is it actually possible to 
revert the compression made by the jpg format to get basically the raw 
image (I doubt that, because then the jpg format wouldn't have lost 
any of the original info)? If that's the case, I would understand, but 
so far I couldn't read that from your replies.

Sorry if I appear a bit dumb on this...

Thanks for all replies

Martin
-- 
E-Mail digital signiert mit Hilfe von GPG - 
http://de.wikipedia.org/wiki/GNU_Privacy_Guard
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 198 bytes
Desc: This is a digitally signed message part.
URL: <http://mail.kde.org/pipermail/digikam-users/attachments/20100119/639dc7fc/attachment.sig>