Ian Clarke - [EMAIL PROTECTED] wrote: > On 19 May 2006, at 10:17, Matthew Toseland wrote: > >>> On Fri, May 19, 2006 at 10:10:03AM -0700, Ian Clarke wrote: >>> >>>> -----BEGIN PGP SIGNED MESSAGE----- >>>> Hash: SHA1 >>>> >>>> Note that compressing anything that has already been compressed, such >>>> as most image, audio, or video formats, is pointless. >>> >>> >>> True, but packing them may be far from pointless. Also, gzip usually >>> manages to squeeze a percent or two out of big video files. > > > That is surprising as any compression algorithm worth its salt should > result in uncompressible files, but I will take your word for it.
Not really surprising. If you had a video compression algorithm, and you found you could make the files smaller by running gzip on them, you *could* add a gzip run as a step in your compression algorithm. But would that be worth the added complexity of the algorithm and time it would take to compress something? Probably not. Also, media file formats are usually made in such a way that the data comes sequentially. If you cut a jpeg in half, you can still view half the jpeg. In general, this is a good feature for media files. Zip-style compression algorithms break that feature. Freenet isn't the general case, however, because it has FEC. _______________________________________________ Devl mailing list Devl@freenetproject.org http://emu.freenetproject.org/cgi-bin/mailman/listinfo/devl
