lossless compression of still images - recommendations?

[Robert Heller]

At Sat, 18 Feb 2017 18:36:49 -0800 "Ubuntu user technical support,  not for general discussions" <ubuntu-users at lists.ubuntu.com> wrote:

> 
> On Sat, 18 Feb 2017 21:33:44 -0500 (EST)
> Robert Heller <heller at deepsoft.com> wrote:
> 
> > At Sat, 18 Feb 2017 21:11:59 +0000 "Ubuntu user technical support,
> > not for general discussions" <ubuntu-users at lists.ubuntu.com> wrote:
> > 
> > > 
> > > On 17 February 2017 at 21:11, Robert Heller <heller at deepsoft.com>
> > > wrote:  
> > > > Use tar+bzip2.  
> > > 
> > > I thought that the OP meant that he wanted to compress the series of
> > > images, making use of the fact that they are little changed from one
> > > image to the next. Much like video is stored.  
> > 
> > That is what tar+bzip2 will do. Bzip2 will see that two "adjacent"
> > images are 90% (or whatever) the same. It will store a token for the
> > each of the "same" parts of the images -- that is, storing the "same"
> > parts once. That is how the *zip programs work. The OP can collect
> > some number of images (maybe a day's worth) and the tar/zip them on a
> > regular basis (daily).
> 
> yes, something like that is what I'll try, a;though perhaps with a
> somewhat smaller dataset. I'll experiment and let you know. Thanks very
> much.

Right, there is some time/space tradeoff that needs to be determined, probably 
experimentally.

> 
> D
> 
> > 
> > > 
> > > Colin
> > >   
> > > >
> > > >
> > > > At Fri, 17 Feb 2017 10:48:16 -0800 "Ubuntu user technical
> > > > support,  not for general discussions"
> > > > <ubuntu-users at lists.ubuntu.com> wrote: 
> > > >>
> > > >> I'm making a long series of exposures of a landscape where there
> > > >> will be only very small (but potentially significant) changes
> > > >> from frame to frame. Basically I'll take a 5MP image every 5
> > > >> seconds for a year, I'll want to timestamp the images and keep
> > > >> them all for later post-processing, as well as being able to
> > > >> retrieve the image closest in time to a specified time and date
> > > >> of interest (which I can't predict.)
> > > >>
> > > >> I want the retrieved image to be faithful to the original, so
> > > >> I'd like to minimize storage needs by compressing the mostly
> > > >> unchanging parts (the landscape won't be moving much.)
> > > >>
> > > >> Does anyone have a recommendation for a program to do this?
> > > >>
> > > >> Dave
> > > >>
> > > >>  
> > > >
> > > > --
> > > > Robert Heller             -- 978-544-6933
> > > > Deepwoods Software        -- Custom Software Services
> > > > http://www.deepsoft.com/  -- Linux Administration Services
> > > > heller at deepsoft.com       -- Webhosting Services
> > > >
> > > >
> > > > --
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> > 
> 
> 
> 

-- 
Robert Heller             -- 978-544-6933
Deepwoods Software        -- Custom Software Services
http://www.deepsoft.com/  -- Linux Administration Services
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