LISTSERV mailing list manager LISTSERV 16.5

Help for CODE4LIB Archives


CODE4LIB Archives

CODE4LIB Archives


CODE4LIB@LISTS.CLIR.ORG


View:

Message:

[

First

|

Previous

|

Next

|

Last

]

By Topic:

[

First

|

Previous

|

Next

|

Last

]

By Author:

[

First

|

Previous

|

Next

|

Last

]

Font:

Proportional Font

LISTSERV Archives

LISTSERV Archives

CODE4LIB Home

CODE4LIB Home

CODE4LIB  April 2013

CODE4LIB April 2013

Subject:

Re: tiff2pdf, then back to pdf?

From:

Kyle Banerjee <[log in to unmask]>

Reply-To:

Code for Libraries <[log in to unmask]>

Date:

Sun, 28 Apr 2013 16:37:12 -0700

Content-Type:

text/plain

Parts/Attachments:

Parts/Attachments

text/plain (81 lines)

Sure, but these are especially small photos -- are these born digital?

Lossless scans of pretty small photos are frequently well over 100MB, and
it takes hardly anything to get a 1GB scan. It costs a fortunate to treat a
thesis (i.e. what's really being preserved is readable text rather than the
artifact itself) as if it were a historical document where texture of the
paper and the like is actually relevant.

The problem we encounter is that people want to scan a tiny photo and blow
it up to poster or wall size. But the source material and the equipment are
typically far more limiting factors than the format unless you're doing
something that's totally nuts. You want maximum flexibility for
unanticipated future needs, but value judgments need to be made up front or
you wind up painting yourself into a corner.

kyle


On Sun, Apr 28, 2013 at 12:40 PM, Simon Spero <[log in to unmask]> wrote:

> On Sun, Apr 28, 2013 at 2:43 AM, Kyle Banerjee <[log in to unmask]
> >wrote:
>
> Every choice people make is about loss. Equipment, optics, lighting,
> > you name it. But for some reason, the instant we're talking about bits of
> > data
> > on a disk, people plan as though capacity were unlimited when most
> > archives are severely underresourced.
> >
>
>  Strictly speaking, it is not correct to say that every choice is about
> loss (or cost), and for once I'm saying this in a case where the difference
> is actually significant. [Someone help edsu to the fainting couch.]
>
> If a particular set of choices are below the Production Possibility
> Frontier<
> http://en.wikipedia.org/wiki/Production%E2%80%93possibility_frontier>,
> then those choices are strictly inferior to those that are on the Frontier.
>  Why is this relevant?  Because, for the situation where lossless image
> storage has a very value,  TIFF is not the most space efficient way of
> storing the data.
>
> A month or so ago I did a few measurements, using a (not necessarily
> representative) color photograph (TIFF extracted from a Canon EOS-10D raw).
>
>
> For lossless conversion, I used uncompressed TIFF, compressed TIFF, PNG,
> and JP2 (100% quality).   Measurements using the ImageMagick "compare"
> utility  confirmed zero signal loss:
>
> -rw-r--r--@ 1 ses  staff    18M Mar 19 14:52
> CRW_4237_tiff_8_uncompressed.tif
> -rw-r--r--@ 1 ses  staff   9.4M Mar 19 14:53
> CRW_4237_tiff_8_compressed.tif
> -rw-r--r--  1 ses  staff   8.2M Mar 19 14:29 CRW_4237-0.png
> -rw-r--r--@ 1 ses  staff   6.1M Mar 19 14:03 CRW_4237_quality_100-0.jp2
>
> For lossy compression, using RMSE as the metric, we can see that JPEG at
> 90% quality is showing measurable signal degradation, with a compression
> ratio of 4.7:1  relative to the JP2 file (vs. 14:1 relative to uncompressed
> tiff, and 7.2:1 for compressed).
>
> $compare  ... CRW_4237_jpg_90.jpg =        459.806 (0.00701619) [1.3M]
> (4.7:1)
>
> JP2 at quality 75 showed slightly less signal loss by RMSE, with a
> compression ratio of 5.5 : 1
>
> $compare  ... CRW_4237_quality_75.jp2 =    457.959 (0.006988)   [1.1M]
> (5.5:1)
>
> Note that the image type was a color photograph; other image types may get
>  better lossless compression using PNG or TIFF.  Also, some people have
> expressed concern over the use of JP2 for archival purposes due to a
> relatively small number of open-source libraries.  On the other hand, JP2
> has some potentially useful properties for distributed replicated
> preservation (layers with fine levels of detail could be split off and
>  stored on fewer replicas).
>
> Simon
>

Top of Message | Previous Page | Permalink

Advanced Options


Options

Log In

Log In

Get Password

Get Password


Search Archives

Search Archives


Subscribe or Unsubscribe

Subscribe or Unsubscribe


Archives

March 2024
February 2024
January 2024
December 2023
November 2023
October 2023
September 2023
August 2023
July 2023
June 2023
May 2023
April 2023
March 2023
February 2023
January 2023
December 2022
November 2022
October 2022
September 2022
August 2022
July 2022
June 2022
May 2022
April 2022
March 2022
February 2022
January 2022
December 2021
November 2021
October 2021
September 2021
August 2021
July 2021
June 2021
May 2021
April 2021
March 2021
February 2021
January 2021
December 2020
November 2020
October 2020
September 2020
August 2020
July 2020
June 2020
May 2020
April 2020
March 2020
February 2020
January 2020
December 2019
November 2019
October 2019
September 2019
August 2019
July 2019
June 2019
May 2019
April 2019
March 2019
February 2019
January 2019
December 2018
November 2018
October 2018
September 2018
August 2018
July 2018
June 2018
May 2018
April 2018
March 2018
February 2018
January 2018
December 2017
November 2017
October 2017
September 2017
August 2017
July 2017
June 2017
May 2017
April 2017
March 2017
February 2017
January 2017
December 2016
November 2016
October 2016
September 2016
August 2016
July 2016
June 2016
May 2016
April 2016
March 2016
February 2016
January 2016
December 2015
November 2015
October 2015
September 2015
August 2015
July 2015
June 2015
May 2015
April 2015
March 2015
February 2015
January 2015
December 2014
November 2014
October 2014
September 2014
August 2014
July 2014
June 2014
May 2014
April 2014
March 2014
February 2014
January 2014
December 2013
November 2013
October 2013
September 2013
August 2013
July 2013
June 2013
May 2013
April 2013
March 2013
February 2013
January 2013
December 2012
November 2012
October 2012
September 2012
August 2012
July 2012
June 2012
May 2012
April 2012
March 2012
February 2012
January 2012
December 2011
November 2011
October 2011
September 2011
August 2011
July 2011
June 2011
May 2011
April 2011
March 2011
February 2011
January 2011
December 2010
November 2010
October 2010
September 2010
August 2010
July 2010
June 2010
May 2010
April 2010
March 2010
February 2010
January 2010
December 2009
November 2009
October 2009
September 2009
August 2009
July 2009
June 2009
May 2009
April 2009
March 2009
February 2009
January 2009
December 2008
November 2008
October 2008
September 2008
August 2008
July 2008
June 2008
May 2008
April 2008
March 2008
February 2008
January 2008
December 2007
November 2007
October 2007
September 2007
August 2007
July 2007
June 2007
May 2007
April 2007
March 2007
February 2007
January 2007
December 2006
November 2006
October 2006
September 2006
August 2006
July 2006
June 2006
May 2006
April 2006
March 2006
February 2006
January 2006
December 2005
November 2005
October 2005
September 2005
August 2005
July 2005
June 2005
May 2005
April 2005
March 2005
February 2005
January 2005
December 2004
November 2004
October 2004
September 2004
August 2004
July 2004
June 2004
May 2004
April 2004
March 2004
February 2004
January 2004
December 2003
November 2003

ATOM RSS1 RSS2



LISTS.CLIR.ORG

CataList Email List Search Powered by the LISTSERV Email List Manager