On Sun, Jun 9, 2013 at 4:01 PM, Dennis E. Hamilton <dennis.hamil...@acm.org> wrote: > Regina is correct about the only two compressions. As far as I know, there > is no way to control which compression is used. (If you save with Password, > all files are always compressed.) Most of the time DEFLATE is used (although > there are two files that are not usually compressed, apparently to make > metadata mining simpler for non-encrypted packages). > > There is currently no way to control the compression in AOO. (The ODF > specification simply stipulates the compression that must be used when > compression is done, not whether compression is done for parts of unencrypted > packages.) >
Does anyone know whether AOO is smart enough to not waste time trying to compress already compressed files, like PNG images? This could make a big difference in presentations. -Rob > I don't think it is the compression that is responsible for the slow-downs, > it has to do with other work that goes on in order to save a file. > > If you are careful about regularly saving manually while you are working, and > you work into a new copy so the starting version can't be damaged, you can > disable auto-save to avoid being interrupted in the midst of something you > are doing. There may be some glitches that cause the time to increase in > certain situations and those are caught from time to time. Using the latest > version usually includes those improvements. I suspect there are some other > performance issues around Save (and Auto-Save) that are more involved. > > - Dennis > > > -----Original Message----- > From: Regina Henschel [mailto:rb.hensc...@t-online.de] > Sent: Sunday, June 9, 2013 11:41 AM > To: users@openoffice.apache.org > Subject: Re: [DISCUSS] ODF file formats vs Zip > > Hi Johnny, > > Johnny Rosenberg schrieb: >> When working with big files, in my case spreadsheets, but possibly >> other types of office files, saving the file will in some cases take a >> lot of time. This is particularly annoying when auto-saving is >> enabled. As I understand it, an ODF is a couple of files, most of them >> XML files, brought together in a single file, then compressed to the >> zip format. >> >> Does the ODF standard specify the compression ratio? > > There are two methods possible STORED and DEFLATED, see > http://docs.oasis-open.org/office/v1.2/os/OpenDocument-v1.2-os-part3.html, > section 2.2. > > If not, it would >> be convenient if the user could specify that. For example, if I prefer >> saving to be as fast as possible, I could specify no compression at >> all, just bring the files together in a tar-ball (if that's allowed) >> or as an uncompressed zip. >> >> I don't know how much of the required time to save a file is used for >> compression, but I imagine that there is room for speed enhancements >> here. >> >> If this is not the way to go, maybe the extension could change as >> well, indicating this is another file format, although conversion to >> and from ODF should be very straight forward… > > Using another compression is still .zip file format. > > ODF has a flat file format without container too. This is implemented in > LO but not in AOO. But in the flat format all pictures are stored in > base64, because there is no folder to store them in original format. > >> >> Thoughts about this? > > It would need tests to see, whether the method STORED is significant faster. > > Kind regards > Regina > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@openoffice.apache.org > For additional commands, e-mail: users-h...@openoffice.apache.org > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@openoffice.apache.org > For additional commands, e-mail: users-h...@openoffice.apache.org > --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@openoffice.apache.org For additional commands, e-mail: users-h...@openoffice.apache.org
