PanoTools NG:
Re: New hardware testing on PTgui performance
Helmut Dersch 2008-Jan-02 20:24:29
Hello Bernhard,
>s cropped TIFFs with deflate compression.
> (zip and deflate are possible, no packbits, so there actually will be a
> certain cost of cpu power)
The point of using compressed images is to zero out
the invalid image areas, which packbits does quite well.
It costs considerably less cpu-power than deflate,
which may slow down writes, or at least keeps
the cpu from doing more useful stuff.
> However, from a practical point of view, warping the images and writing
> to temp files is not the most time consuming part of the process.
> (Well, the badly written temp files are a problem in the blending
> step.). You can speed up warping almost linear by adding more CPU power
> and a higher number of cores (with nona and PTGui stitcher).
> But: Most of the time is needed to blend the images. This is certainly
> caused by the assumption of the software authors that the whole
panorama
> image can be accessed without extensive computational cost (in terms of
> harddisk access and memory needs). I am not sure if this is a problem
> inherent to the blending process - however - all blenders (enblend,
> PTGui, smartblend) do scale badly (only one CPU, "random access" in the
> image)...
>
> Just as a number: I have compared 2 methods with PTGui:
> - one is rendering a large panorama as one large image: took 2h 38min,
> warping (and temp file writing) took only 30min,
I am currently only working on the warp-part. Maybe
you could add warp-times to your speed-comparison
chart. If the quoted 30min correspond to your set of posted
test-images: this can be reduced significantly.
I will look into the blender-issue.
Best regards
Helmut Dersch
--
<*> Wiki: http://wiki.panotools.org
<*> User Guidelines: http://wiki.panotools.org/User_Guidelines
<*> Nabble (Web) http://www.nabble.com/PanoToolsNG-f15658.html
<*> NG Member Map http://www.panomaps.com/ng
<*> Moderators/List Admins: #removed#
Yahoo! Groups Links
<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/PanoToolsNG/
<*> Your email settings:
Individual Email | Traditional
<*> To change settings online go to:
http://groups.yahoo.com/group/PanoToolsNG/join
(Yahoo! ID required)
<*> To change settings via email:
mailto:#removed#
mailto:#removed#
<*> To unsubscribe from this group, send an email to:
#removed#
<*> Your use of Yahoo! Groups is subject to:
http://docs.yahoo.com/info/terms/