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Re: Floating Preview: some more candy?

Posted: 12 Nov 2015 18:54
by nerdweed
Thanks Don and Qwerty. Works nicely :tup:

Re: Floating Preview: some more candy?

Posted: 16 Nov 2015 01:11
by FluxTorpedoe
admin wrote:Good move but I'm not even sure it would bring so much speed. The shrinking seems to be the bottleneck (unless your disk is slow). But, I will make some tests if I find the time...
The preloading would be too much work. The current architecture is not made for this. Maybe later when I have more time.
Oh ok, no problem ! :)

Now, well, the least I can do since I asked and you invested quite some time recently in FP, is to try and help by investigating the whole image performance behavior (and not only the potential role of preloading for future reference).

So I used XYplorer and Faststone Viewer (Color Management disabled), with FastPictureViewer Codec Pack (under Windows 7 SP1 x64, crappy integrated GPU IntelHD, basic 5200rpm HDD).
It goes w/o saying that my goal isn’t to compare softs, but to help determine what may happen behind the scenes.

TL;DR! :arrow: Conclusion:
   Regardless of HDD reads:
   — The preloading seems to have an impact (though let’s forget it for now, no problem!)
   — But mainly, the caching seems to play a huge part in browsing between pics, so do you think this one would be easier to implement?
   — TIFs would greatly benefit from using their embedded preview (as may be done, presumably, in highspeed thumbnails generation)

   Details below if/when you feel like it. ;)

Hoping this might help,


[» Assumptions written in green]

• Files:
   — 15Mpixels "obscure" RAWs (recent X3F) only displayed thanks to FPV [~50MB each]
   — The same converted to TIF 16bit/channel with ProPhotoRGB profile [~80MB]
   — The same in JPG sRGB 98% quality [9MB]

• Results
   — First opening of JPG or X3F: ~2sec in XY, slightly but notably faster than ~2.5sec in FS
   — First opening of TIF: ~6sec in XY, sloooooowwwweeeerrr than ~1sec in FS
   — Subsequent opening of a same image: very fast with <1sec for XY whatever the format! while no gain of speed with ~2sec for FS whatever the format [» XY caching]
   Browsing between two pics after a first opening (to discount HDD loading): [» FS caching]
   — Back and forth between JPG: 1sec in XY, instantaneous (literally) in FS
   — Back and forth between X3F: ~<2sec in XY, slightly slower than ~>1sec in FS
   — Back and forth between TIF: still ~6sec in XY, while <1sec in FS
   — Back and forth alternating JGP and X3F: no difference than while browsing between same format
• Side test with a series of 2Mpixels JPGs:
   — Browsing normally: ~0.5sec in XY, instantaneous in FS [» FS preloading]
   — Browsing back or forth very fast, the first time: ~0.5sec in XY, nearly instantaneous in FS [» No caching, no time to preload]
   — Browsing back then forth very fast (or subsequent passes): ~0.5sec in XY, instantaneous in FS [» FS caching]
• Side test with a 300MB DNG:
   — Both XY and FS: same as above for the JPG behaviour

   — XY manages the reading part much better than FS in general, but especially for subsequent openings — by caching the first read (?)
   — FS manages the browsing part much faster, 1. by preloading, and 2. by caching the already opened pics (at least ~10 I would say)
   — TIF specific: XY reads the real image while FS uses its same-size embedded preview
      Corroborated by 1. there are some (rare) TIFs for which FS displays only garbage whereas XY displays all, and 2. FS has the exact same behaviour with the TIFs as with the DNG, and XY and FS have the same behaviour for the DNG: they only use its embedded 150Kpixels preview instead of the overly huge real pic. Extra note: The slowness was the same for XY thumbnails before the highspeed option.

Re: Floating Preview: some more candy?

Posted: 16 Nov 2015 09:59
by admin
Wow, thanks for the facts, and I agree with all your assumptions (and where they concern what XY does internally they are correct).

1) In the meantime I think I found a solution to the preload task. It's planned for 16.10. :)

2) Embedded thumbnail. I don't use this in FP because I want to have the highest quality, a fast MDBU, and fast zooming. Let's first see what the preloading brings before we talk about using the embedded thumbnail.

Re: Floating Preview: some more candy?

Posted: 25 Dec 2015 01:26
by FluxTorpedoe
(Belated) Thanks for the feedback!
And I just see that a lot of love is coming to FP… :biggrin:

Re: Floating Preview: some more candy?

Posted: 25 Dec 2015 13:35
by admin
Yes, the preload stuff will come, but a little later, 16.20 or 16.30.