On Thu, Oct 19, 2006 at 09:44:21PM -0400, Bob Shell wrote: > > On Oct 19, 2006, at 6:00 PM, J. C. O'Connell wrote: > > > Compressing and uncompressing is SLOWER > > Than using uncompressed files. > > Actually, that used to be a consideration back in the old days of > slow chips. With today's machines the difference is not even > detectable.
Oh, it's detectable - very detectable. Writing to secondary media (such as a CF card) is slow, slow, slow - I/O is the major bottleneck in modern computer systems. You can afford a whole lot of CPU cycles if the payback is reduced I/O time. JCO is just plain wrong on this (not that you'll ever get him to admit it). There's been an interesting thread on this topic on dpreview; a guy there who has written lossless JPEG compression routines estimates that just putting compression in the firmware on the K10D would more than pay for itself in I/O time savings, even using pretty conservative estimates for compression ratios. And if there were a hardware assist in the PRIME chip ... Not to mention the increase in the number of images you could get per GB of memory card, reduced upload time, etc. I'm sure we'll see compressed DNG available on the K10D fairly soon, once the rush to get firmware version 1.0 ready is over. -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net
