kaycee said:
Does anyone know how to change a picture back to its original size once its
been comressed? Or how to enlarge it back to original quality so that it can
be printed clearly? THanks!!!
I think you are using wrong terminology here. Pictures are made up of
dots (called pixels). In general, the more dots the better the quality,
but, since dots take up file space, more dots mean bigger picture files.
There are only two ways of reducing the file size of a picture: you can
compress it or reduce the number of dots (pixels) it contains. To reduce
the number of pixels you must throw some away. The programs that do this
are very selective about the pixels they discard and choose those that
will have the least effect on the appearance of the picture, but once
they have been thrown away they are gone forever - you can never get
them back again.
Compression is a software function that reduces a picture's file size
without noticeably affecting its appearance. Pictures with a filetype
(or extension) of JPG are compressed pictures (there are others).
Uncompressed pictures usually have a filetype of BMP (again there are
others). If you compress a BMP into a JPG and then uncompress it back to
a BMP you get very nearly the same picture you started with. Each time
you do this to the same picture, the quality gets a little worse. Do it
once and its not very noticeable, but do it several times and it becomes
very obvious. (There are compression methods that don't degrade the
picture, but they are not used as much as JPG compression).
So, if its really compressed you can uncompress it and get pretty close
to your original picture again, but if you reduced the resolution then
you are stuffed.
