T
tinnews
I think we can probably make some fairly good guesses.
E
Edward Kroeze
Eddie said:
With 'compression' I think you mean 'lossy compression'.
"Lossless compression" is perfectly acceptable and used rather a lot.
LZW-compression doesn't loose any data and reduces sizes quite nicely.
For non-TIFF formats, you could take a look at PiNG.
Which gives generally even better compression (YMMV) compared
to LZW-comprssion and is supposed to be an open standard.
Uhm, yes... that seems to be the main aim of compression
anyway (lossless or lossy)
Take care,
E.
E
Eddie
Good points EdwardEdward Kroeze said:With 'compression' I think you mean 'lossy compression'.
"Lossless compression" is perfectly acceptable and used rather a lot.
LZW-compression doesn't loose any data and reduces sizes quite nicely.
For non-TIFF formats, you could take a look at PiNG.
Which gives generally even better compression (YMMV) compared
to LZW-comprssion and is supposed to be an open standard.
Uhm, yes... that seems to be the main aim of compression
anyway (lossless or lossy)
Take care,
E.
Eddie
J
jeremy
Eddie said:
LOSSY compression may be out of the question, but there are NON-LOSSY
compression schemes that do not result in any loss of image information.
Although FOR THE LONG TERM, using any compression may be unwise, as there is
no telling if the compression schemes will be supported a hundred years from
now. Already there are early compressed versions of the TIF format that not
all editing packages can read.
Also, compressed files may be more at risk in the event of a partial media
failure, because the loss of even one sector might make the entire file
unable to be opened. So there are good reasons to avoid compression
especially if the resulting files are meant for long-term archiving.
As for format, just consider that FlashPix (.FPX) format is dead and already
some editors don't support it, including the latest versions of PS. And the
Kodak ImagePac format that was used on Photo CDs has been unused for a
couple of years, making it only a matter of time before editing software
will be stop supporting it.
Get those Photo CD files migrated over to TIF while it is still easy to do
so.
G
Guest
Eddie said:
Why? There's no loss in TIFF compression.
G
Guest
I think we can probably make some fairly good guesses.
[/QUOTE]An anthropolist of the futre may disagree.
R
rafe b
In some cases, there's no point in it, either.
I've seen cases where TIF compression backfires and
makes the "compressed" images larger than the original.
rafe b
www.terrapinphoto.com
K
Ken Weitzel
rafe said:
Hi...
I'd respectfully suggest that if the space saving is
essential, and you just must do it, I'd use only something
like .zip or .rar. And I'd include in a few of the discs
a copy of the dos unzip or unrar, to make sure one of them
survives.
I'd zip or rar individual pictures so that a zip or rar
failure wouldn't eliminate the whole shebang.
I'd also include a cd and a dvd dos boot disk. And on those
disks I'd include some old dos based photo software; something
like an old shareware copy of paint shop pro. Using this, I
(future generations) might be able to find a path (or paths)
from .tiff to whatever is current.
And while I'm here, a heads-up for everyone, with the hope
that it might save someone else a little pain. Have an old laptop
in the country that I use only for storage of pictures to move
back to the city (cards used to be real expensive). Put a dvd
down on the open tray, and the power failed (no battery). Left
it sitting there. Power came back, the drawer closed, and
completely irrevocably destroyed the dvd. Peeled the "shiny"
stuff right off. So - don't leave cd/dvd's sitting improperly
seated.
Take care.
Ken
Take care.
Ken
E
Eddie
Ken, I believe that Zip compression works best on text data, not a greatKen Weitzel said:
deal on Pics, which is why jpg developed their compression format. Though I
suspect that your point is that zip decompresses to original file.
But I still prefer non-compressed file. Tiff will have to do.
Regards
Eddie
J
jeremy
Eddie said:
JPEG 2000 may be the next star image format. It has lossless compression
and is alleged to result in smaller file size than TIF.
K
Ken Weitzel
jeremy said:
Hi..
I doubt it, it's been around for quite a while, and hasn't made
any progress toward popularity at all.
Just for the heck of it, I zipped a few tiff's - started at 40 megs,
zipped to an average of about 27 megs.
But I agree that the way to go is uncompressed, make it as easy and
safe as possible for future generations who may want to see them.
Take care.
Ken
S
Scott W
I would say that you want to archive both tiff and jpeg. Whereas tiffKen said:
might be a file you are comfortable with and understand many people
will not even recognize it as an image file. Film scanned at high
resolution and saved as 16 bit/color tiffs take up a lot of room, more
then your relatives might want to deal with. There are programs that
will convert all your tiffs to jpeg format and resize at the same time
if desired. The point is future generations might be more willing to
deal with your photos is the collection can fit on to a fairly small
part of their hard drive, but not so interested if the collection takes
up boxes of DVD.
This is not to say you delete or destroy the full resolution version,
but that you have the collection in a smaller format for ease of use.
Scott
C
Chris Palmer
Scott said:
I wouldn't want to put a downer on this worthwhile and admirable
exercise [which I'm doing too] but here are a few points to consider:
1 Archiving on optical media is unproven. Be prepared to copy the data
onto fresh media after a few years. Think back only ten years - floppy
discs were contenders for "archival" media! Nowadays many new computers
don't have floppy drives... and I found to my horror that some essays I
wrote and saved on floppies only about seven years ago are now
unreadable. I think that optical media are more hardwearing than
floppies, but there are concerns about the stability of the dyes used
in CDs and DVDs. You can help by keeping them in a dark place, but test
them regularly and be prepared to migrate the files.
2 Keep your eye on developments! Be prapared to copy and convert your
images often. Hopefully, it will be a quick and easy process
[especially if you avoid zip files, though using internal zip
compression in TIFFs ought to be feasible], and future storage media
will have the capacity to store many DVDs! You'll eventually get the
lot onto a chip of some sort, I imagine. None of us are going to be
around forever, so leave clear instructions to this effect for whoever
you want to care for your collection in the future.
3 In around fifteen years, we have moved from the kilobyte era to the
terabyte era. File size will not be an issue in the future. I'm sure
that screens will resolve high definition images at 300dpi one day!
I think that scanning photos and putting the discs in a box to be
forgotten about for 50 years is unrealistic if you really want them to
survive. Repeat the mantra: Care and Maintenance!
Good luck & best wishes.