Responds to myself... I've done a quick and naïve implementation of solution 3. You can find it on the branch "uhq_thumbnails" in main repo.
Finally, changes are quite small, and apparently, it seems to work well here, but there's still some questions : - As I don't know the rendering code very well, it's really possible that my little hack cause weird situations... - Changing the prefs doesn't invalidate relevant cache numbers. - My English descriptions for the prefs are awefull, I know it ;) Thanks for testing Aldric Le 15/01/2015 22:21, AlicVB a écrit : > Hi all, > > I have something to discuss with core devs... > > I find thumbnail quality rendering quite bad. This is especially > visible with large rendering, for example full preview, or with 1 > image per row. Althought when you work in dr, image are fine, when you > come back in lt, they are rendered really very "soft" (not sure it's > the right term here) This append whenever you have tweaked the image > or you don't change default settings. I do have > "plugins/lighttable/low_quality_thumbnails" set to FALSE in dtrc... > > I've tried to track down this behaviour, and ended here : > iop/demosaic.c:1485 : > if you add " || (piece->pipe->type == DT_DEV_PIXELPIPE_THUMBNAIL && > qual > 0)" to the if statement, it seems you get the "normal" > rendering. (of course it's not a "fix", it's just to show one possible > source of the pb) > > I understand perfectly that this code path is here to speedup > thumbnail generation and that is good. Some quick test show a speedup > at ~40x for small thumbnails and ~10x for full preview. > > What I would like to propose is : > 1- Enhance this code path (sadly, I've not the skill to do that... but > it's the best solution if it's possible) > 2- Add a config option to always do "super-hight-quality" thumbnails. > I think lot of us have really powerfull hardware these days, and may > prefer to waste some ms and get better thumbnails. > 3- Add a config option to do "super-hight-quality" thumbnails > depending on image size request : something like "use ultra-hight > quality processing for thumbnail larger than ... x ... > 4- Process thumbnails with ultra-hight quality for full preview > (eventually with a config option). But what if 1 image par row (or 2 > for large screens) > > I've to admit than option 3 has my preference, because of the > flexibility it give, one drawback is, as always, that it add some > complexity for "beginners". Once we decide if and which option we > want, I should be able do it (apart from n°1). > > How does that sound ? Is it something we want ? > > Thanks > Aldric ------------------------------------------------------------------------------ New Year. New Location. New Benefits. New Data Center in Ashburn, VA. GigeNET is offering a free month of service with a new server in Ashburn. Choose from 2 high performing configs, both with 100TB of bandwidth. Higher redundancy.Lower latency.Increased capacity.Completely compliant. http://p.sf.net/sfu/gigenet _______________________________________________ darktable-devel mailing list darktable-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/darktable-devel
