<html>
  <head>
    <meta content="text/html; charset=UTF-8" http-equiv="Content-Type">
  </head>
  <body bgcolor="#FFFFFF" text="#000000">
    <div class="moz-cite-prefix">A similar term to 'reversible'  is
      'lossless', contrasted with 'lossy'.  <br>
      <br>
      Translations across natural languages (between humans) are
      inherently lossy, and for other than the simplest texts,
      irreversible.  <br>
      <br>
      Image transformation processes are often characterized as either
      lossy (and probably irreversible) or lossless.  An example of
      lossy transformation is image digitization, for example where a
      scanner converts an analog image to a pixel stream.  A lossless
      image transformation is only possible with images 'born digital',
      where the full content, including annotations and metadata, of the
      original image is preserved and can be exploited to create an
      exact copy of the original.<br>
      <br>
      Terry<br>
      <br>
      On 11/20/2016 2:19 AM, John Garrett wrote:<br>
    </div>
    <blockquote cite="mid:3b7301d242fe$69c8a810$3d59f830$@his.com"
      type="cite">
      <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
      <meta name="Generator" content="Microsoft Word 15 (filtered
        medium)">
      <!--[if !mso]><style>v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style><![endif]-->
      <style><!--
/* Font Definitions */
@font-face
        {font-family:"Cambria Math";
        panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
        {font-family:Calibri;
        panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
        {margin:0in;
        margin-bottom:.0001pt;
        font-size:11.0pt;
        font-family:"Calibri",sans-serif;}
a:link, span.MsoHyperlink
        {mso-style-priority:99;
        color:blue;
        text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
        {mso-style-priority:99;
        color:purple;
        text-decoration:underline;}
span.EmailStyle17
        {mso-style-type:personal;
        font-family:"Calibri",sans-serif;
        color:windowtext;}
span.EmailStyle18
        {mso-style-type:personal;
        font-family:"Calibri",sans-serif;
        color:#1F497D;}
span.EmailStyle19
        {mso-style-type:personal-reply;
        font-family:"Calibri",sans-serif;
        color:#1F497D;}
.MsoChpDefault
        {mso-style-type:export-only;
        font-size:10.0pt;}
@page WordSection1
        {size:8.5in 11.0in;
        margin:70.85pt 70.85pt 70.85pt 70.85pt;}
div.WordSection1
        {page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1027" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
      <div class="WordSection1">
        <p class="MsoNormal"><span style="color:#1F497D">Sorry.  Forgot
            to say that one to one mapping being discussed is between
            the entities in the new representation and the equivalent
            entities in the original representation.<o:p></o:p></span></p>
        <p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span style="color:#1F497D">For example,
            the ‘A’ character in Unicode has a one to one mapping back
            to the ‘A’ character in ASCII.<o:p></o:p></span></p>
        <p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span style="color:#1F497D">Wishing you
            prosperity and peace,<o:p></o:p></span></p>
        <p class="MsoNormal"><span style="color:#1F497D">-JOhn <o:p></o:p></span></p>
        <p class="MsoNormal"><a moz-do-not-send="true"
            name="_MailEndCompose"><span style="color:#1F497D"><o:p> </o:p></span></a></p>
        <div>
          <div style="border:none;border-top:solid #E1E1E1
            1.0pt;padding:3.0pt 0in 0in 0in">
            <p class="MsoNormal"><b>From:</b> John Garrett
              [<a class="moz-txt-link-freetext" href="mailto:garrett@his.com">mailto:garrett@his.com</a>] <br>
              <b>Sent:</b> Sunday, November 20, 2016 2:15 AM<br>
              <b>To:</b> 'MOIMS-Data Archive Ingestion'
              <a class="moz-txt-link-rfc2396E" href="mailto:moims-dai@mailman.ccsds.org"><moims-dai@mailman.ccsds.org></a><br>
              <b>Subject:</b> RE: [Moims-dai] Question about Reversible
              Transformation<o:p></o:p></p>
          </div>
        </div>
        <p class="MsoNormal"><o:p> </o:p></p>
        <p class="MsoNormal"><span style="color:#1F497D">Hi,<o:p></o:p></span></p>
        <p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span style="color:#1F497D">I think the
            explanation of Reversible Transformation with examples later
            in the document is helpful in understanding what is meant.<o:p></o:p></span></p>
        <p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span style="color:#1F497D">It might help
            to replace ‘entity’ with ‘component’ or ‘item’ or ‘thing’ or
            ‘object’.<o:p></o:p></span></p>
        <p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span style="color:#1F497D">For version 3
            that we are working on now.  I think I might drop the second
            ‘resulting’ and ‘base’ in an updated definition.  Would that
            change anyone’s understanding the term?<o:p></o:p></span></p>
        <p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span style="color:#1F497D">Wishing you
            prosperity and peace,<o:p></o:p></span></p>
        <p class="MsoNormal"><span style="color:#1F497D">-JOhn<o:p></o:p></span></p>
        <p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
        <div>
          <div style="border:none;border-top:solid #E1E1E1
            1.0pt;padding:3.0pt 0in 0in 0in">
            <p class="MsoNormal"><b>From:</b> MOIMS-DAI [<a
                moz-do-not-send="true"
                href="mailto:moims-dai-bounces@mailman.ccsds.org"><a class="moz-txt-link-freetext" href="mailto:moims-dai-bounces@mailman.ccsds.org">mailto:moims-dai-bounces@mailman.ccsds.org</a></a>]
              <b>On Behalf Of </b>Caillet Claire<br>
              <b>Sent:</b> Thursday, November 17, 2016 4:17 AM<br>
              <b>To:</b> MOIMS-Data Archive Ingestion <<a
                moz-do-not-send="true"
                href="mailto:moims-dai@mailman.ccsds.org"><a class="moz-txt-link-abbreviated" href="mailto:moims-dai@mailman.ccsds.org">moims-dai@mailman.ccsds.org</a></a>><br>
              <b>Subject:</b> [Moims-dai] Question about Reversible
              Transformation<o:p></o:p></p>
          </div>
        </div>
        <p class="MsoNormal"><o:p> </o:p></p>
        <p class="MsoNormal">Dear all,<o:p></o:p></p>
        <p class="MsoNormal"><o:p> </o:p></p>
        <p class="MsoNormal">Once again, in the translation work of the
          OAIS, we have some questions. It is about the definition of
          the <b>Reversible Transformation</b> (A Transformation in
          which the new representation defines a set (or a subset) of
          resulting entities that are equivalent to the resulting
          entities defined by the original representation.  This means
          that there is a one-to-one mapping back to the original
          representation and its set of base entities.).<o:p></o:p></p>
        <p class="MsoNormal"><o:p> </o:p></p>
        <p class="MsoNormal">What is meant by “resulting entities” and
          “base entities” ? Is the one-to-one mapping between the
          original representation and its base entities or between the
          new and the original representation base entities ?<o:p></o:p></p>
        <p class="MsoNormal" style="text-autospace:none"><span
            style="color:black;mso-fareast-language:FR"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span style="mso-fareast-language:FR">Thanks
            for you help.<o:p></o:p></span></p>
        <p class="MsoNormal"
          style="mso-margin-top-alt:auto;margin-bottom:6.0pt"><span
style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:FR"
            lang="FR">_______________________________________________________________________</span><span
            style="mso-fareast-language:FR" lang="FR"><o:p></o:p></span></p>
        <p class="MsoNormal"><!--[if gte vml 1]><v:shapetype id="_x0000_t75" coordsize="21600,21600" o:spt="75" o:preferrelative="t" path="m@4@5l@4@11@9@11@9@5xe" filled="f" stroked="f">
<v:stroke joinstyle="miter" />
<v:formulas>
<v:f eqn="if lineDrawn pixelLineWidth 0" />
<v:f eqn="sum @0 1 0" />
<v:f eqn="sum 0 0 @1" />
<v:f eqn="prod @2 1 2" />
<v:f eqn="prod @3 21600 pixelWidth" />
<v:f eqn="prod @3 21600 pixelHeight" />
<v:f eqn="sum @0 0 1" />
<v:f eqn="prod @6 1 2" />
<v:f eqn="prod @7 21600 pixelWidth" />
<v:f eqn="sum @8 21600 0" />
<v:f eqn="prod @7 21600 pixelHeight" />
<v:f eqn="sum @10 21600 0" />
</v:formulas>
<v:path o:extrusionok="f" gradientshapeok="t" o:connecttype="rect" />
<o:lock v:ext="edit" aspectratio="t" />
</v:shapetype><v:shape id="Image_x0020_1" o:spid="_x0000_s1026" type="#_x0000_t75" style='position:absolute;margin-left:0;margin-top:4.05pt;width:31.5pt;height:34.1pt;z-index:251659264;visibility:visible;mso-wrap-style:square;mso-width-percent:0;mso-height-percent:0;mso-wrap-distance-left:9pt;mso-wrap-distance-top:0;mso-wrap-distance-right:9pt;mso-wrap-distance-bottom:0;mso-position-horizontal:left;mso-position-horizontal-relative:text;mso-position-vertical:absolute;mso-position-vertical-relative:text;mso-width-percent:0;mso-height-percent:0;mso-width-relative:page;mso-height-relative:page'>
<v:imagedata src="imap://terry%2Elongstreth@imap.comcast.net:993/fetch%3EUID%3E/Processed/MOIMS%3E1125657?header=quotebody&part=1.1.2&filename=image001.jpg" o:title="" />
<w:wrap type="square"/>
</v:shape><![endif]--><!--[if !vml]--><img
            src="cid:part4.07030102.09020500@comcast.net"
            v:shapes="Image_x0020_1" align="left" height="46"
            hspace="12" width="42"><!--[endif]--><b><span
style="font-size:10.0pt;font-family:"Arial",sans-serif;mso-fareast-language:FR"
              lang="FR">Claire Caillet<o:p></o:p></span></b></p>
        <p class="MsoNormal"><b><span
style="font-size:8.0pt;font-family:"Arial",sans-serif;mso-fareast-language:FR"
              lang="FR">CNES</span></b><span
            style="font-size:8.0pt;mso-fareast-language:FR" lang="FR"><o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:FR"
            lang="FR">DCT/PS/TVI</span><span
            style="mso-fareast-language:FR" lang="FR"><o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:FR"
            lang="FR"> </span><span style="mso-fareast-language:FR"
            lang="FR"><o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:FR"
            lang="FR">Centre Spatial de Toulouse</span><span
            style="mso-fareast-language:FR" lang="FR"><o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:FR"
            lang="FR">Tel.: +33 5 61 28 14 38<o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:FR"
            lang="IT">e-mail : <a moz-do-not-send="true"
              href="mailto:claire.caillet@cnes.fr">claire.caillet@cnes.fr</a><o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:FR"
            lang="IT"> </span><span style="mso-fareast-language:FR"
            lang="IT"><o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:FR"
            lang="FR">18 Avenue Edouard Belin </span><span
            style="mso-fareast-language:FR" lang="FR"><o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:FR"
            lang="FR">31 401 Toulouse Cedex 4<o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:FR"
            lang="FR">FRANCE<o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:FR"
            lang="FR">_______________________________________________________________________</span><span
            style="mso-fareast-language:FR" lang="FR"><o:p></o:p></span></p>
        <p class="MsoNormal"><span lang="FR"><o:p> </o:p></span></p>
      </div>
      <br>
      <fieldset class="mimeAttachmentHeader"></fieldset>
      <br>
      <pre wrap="">_______________________________________________
MOIMS-DAI mailing list
<a class="moz-txt-link-abbreviated" href="mailto:MOIMS-DAI@mailman.ccsds.org">MOIMS-DAI@mailman.ccsds.org</a>
<a class="moz-txt-link-freetext" href="https://mailman.ccsds.org/cgi-bin/mailman/listinfo/moims-dai">https://mailman.ccsds.org/cgi-bin/mailman/listinfo/moims-dai</a>
</pre>
    </blockquote>
    <br>
    <br>
    <div class="moz-signature">-- <br>
      <img src="cid:part6.00090006.06050006@comcast.net" border="0"></div>
  </body>
</html>