PanoTools mailing list archive

Mailinglist:PanoTools NG
Sender:Helmut Dersch
Date/Time: 8-Mar-2008 09:41:08 +0100
Subject:Re: Fast Gigapixel Stitching on the Playstation 3

Thread:


--- In #removed#, Jim Watters <jwatters@...> wrote:
>
> As a comparison, what is the time to just read and write all the images 
> without any processing?

I have no good data, but maybe this is useful: The default output
of PTStitcherNG is layered TIFF. To create flat TIFF-files
the data must be reread and merged. This involves little if any
data processing, just disk-IO, and takes appr. 10min on the PS3
for the 1.4 Gigapixel testimage. The default warp&blend process 
takes ~2 read/write cycles, so 22min compared to 2*10min.

Or, from another viewpoint: For large cylindrical panoramas 
PTStitcherNG approaches a processing speed of 1.04 million output-
rgb-pixels/sec. For 3 bytes/pixel (uncompressed) and two read/write
cycles this amounts to 12MByte/s. You cannot get much more average 
IO-speed on the PS3, which has a standard SATA-drive with ~30MByte/s 
peak speed.

We are actually working with compressed data, and the numbers are
slightly different, but the ratio  image IO/(imageIO+warp&blend) 
is similar. 

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/
 

Next message:

Previous message: