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<DIV><FONT face=Arial size=2>Hi,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Your calculus seem good.</FONT></DIV>
<DIV><FONT face=Arial size=2>In your original and final image, what are the
maximum and minimum in the pixel values ?</FONT></DIV>
<DIV><FONT face=Arial size=2>If the ratio between the max and the number of
possible values for the original and final images</FONT></DIV>
<DIV><FONT face=Arial size=2>are same, then your conversion is
correct.</FONT></DIV>
<DIV><FONT face=Arial size=2>In this case, it will only be a lookup table
problem. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Cheers</FONT></DIV>
<DIV><FONT face=Arial size=2>Benoit Regrain</FONT></DIV>
<DIV><FONT face=Arial size=2> </DIV>
<DIV><BR></DIV></FONT>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=olivier.stern@swing.be
href="mailto:olivier.stern@swing.be">olivier.stern@swing.be</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=Dcmlib@creatis.insa-lyon.fr
href="mailto:Dcmlib@creatis.insa-lyon.fr">Dcmlib@creatis.insa-lyon.fr</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Tuesday, August 09, 2005 3:59
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> [Dcmlib] Image conversion</DIV>
<DIV><BR></DIV><BR>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: justify"><SPAN
lang=EN-GB style="mso-ansi-language: EN-GB">Hello,<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: justify"><SPAN
lang=EN-GB style="mso-ansi-language: EN-GB"> <o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: justify"><SPAN
lang=EN-GB style="mso-ansi-language: EN-GB">I have a little trouble converting
images. I got DICOM images with 16 bits allocated, 12 bits stored and 11 as
high bit. I'd like to change them to 8 bits allocated, 8 bits stored and 7 as
high bit.<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: justify"><SPAN
lang=EN-GB style="mso-ansi-language: EN-GB"> <o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: justify"><SPAN
lang=EN-GB style="mso-ansi-language: EN-GB">What I've done first was taking
the highest value of pixels on one image and the lowest, and made a conversion
to value between 0 and 255 (thanks to Jean-Perre Roux). But this conversion
wasn't the same from one image to another because the highest value and the
lowest change. What I need is a constant conversion so what I 've done
is: as the highest theoric value that a file with 12 bits stored can take is
4095 and a file with 8 bits stored is 255, all pixels of the original images
were devised by 16 (4096/256 = 16). But the output image was very
dark, either deleting 0x0028,0x1050 and 0x0028,0x1051. If I devise by 4 I get
a relatively good result but I can't say why. Could anyone explain me if what
I m doing is correct?<BR><BR>Olivier<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-GB
style="mso-ansi-language: EN-GB"><o:p> </o:p></SPAN></P><BR><BR>
<P>
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