<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> <!--Converted with LaTeX2HTML 2002-2-1 (1.71) original version by: Nikos Drakos, CBLU, University of Leeds * revised and updated by: Marcus Hennecke, Ross Moore, Herb Swan * with significant contributions from: Jens Lippmann, Marek Rouchal, Martin Wilck and others --> <HTML> <HEAD> <TITLE>B.2.2.2 Pixel registration</TITLE> <META NAME="description" CONTENT="B.2.2.2 Pixel registration"> <META NAME="keywords" CONTENT="GMT_Docs"> <META NAME="resource-type" CONTENT="document"> <META NAME="distribution" CONTENT="global"> <META NAME="Generator" CONTENT="LaTeX2HTML v2002-2-1"> <META HTTP-EQUIV="Content-Style-Type" CONTENT="text/css"> <LINK REL="STYLESHEET" HREF="GMT_Docs.css"> <LINK REL="previous" HREF="node183.html"> <LINK REL="up" HREF="node182.html"> <LINK REL="next" HREF="node185.html"> </HEAD> <BODY bgcolor="#ffffff"> <!--Navigation Panel--> <A NAME="tex2html5267" HREF="node185.html"> <IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next.png"></A> <A NAME="tex2html5261" HREF="node182.html"> <IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up.png"></A> <A NAME="tex2html5257" HREF="node183.html"> <IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="prev.png"></A> <A NAME="tex2html5263" HREF="node1.html"> <IMG WIDTH="65" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="contents" SRC="contents.png"></A> <A NAME="tex2html5265" HREF="node256.html"> <IMG WIDTH="43" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="index" SRC="index.png"></A> <BR> <B> Next:</B> <A NAME="tex2html5268" HREF="node185.html">B.2.3 Boundary Conditions for</A> <B> Up:</B> <A NAME="tex2html5262" HREF="node182.html">B.2.2 Gridline and Pixel</A> <B> Previous:</B> <A NAME="tex2html5258" HREF="node183.html">B.2.2.1 Gridline registration</A> <B> <A NAME="tex2html5264" HREF="node1.html">Contents</A></B> <B> <A NAME="tex2html5266" HREF="node256.html">Index</A></B> <BR> <BR> <!--End of Navigation Panel--> <H3><A NAME="SECTION001922200000000000000"></A> <A NAME="29339"></A> <BR> B.2.2.2 Pixel registration </H3> <P> Here, the nodes are centered in the grid cells, i.e., the areas between grid lines, and the data points represent the average values within each cell (Figure <A HREF="#fig:GMT_App_B_2">B.2</A>. In the case of pixel registration the number of nodes are related to region and grid spacing by <BR> <P> <BR><P></P> <DIV ALIGN="CENTER"> <!-- MATH \begin{displaymath} \begin{array}{ccl} nx & = & (x_{max} - x_{min}) / x_{inc} \\ ny & = & (y_{max} - y_{min}) / y_{inc} \end{array} \end{displaymath} --> <IMG WIDTH="171" HEIGHT="45" BORDER="0" SRC="img223.png" ALT="\begin{displaymath}\begin{array}{ccl} nx & = & (x_{max} - x_{min}) / x_{inc} \\ ny & = & (y_{max} - y_{min}) / y_{inc} \end{array} \end{displaymath}"> </DIV> <BR CLEAR="ALL"> <P></P> <P> Thus, given the same region (<B>-R</B>), the pixel node registered grids have one less column and one less row than the grid line registered grids; here we find <IMG WIDTH="81" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" SRC="img224.png" ALT="$nx = ny = 3$">. <P> <DIV ALIGN="CENTER"><A NAME="fig:GMT_App_B_2"></A><A NAME="29682"></A> <TABLE> <CAPTION ALIGN="BOTTOM"><STRONG>Figure B.2:</STRONG> Pixel registration of data nodes.</CAPTION> <TR><TD> <DIV ALIGN="CENTER"><IMG WIDTH="306" HEIGHT="162" ALIGN="BOTTOM" BORDER="0" SRC="img225.png" ALT="\includegraphics{scripts/GMT_App_B_2}"></DIV></TD></TR> </TABLE> </DIV> <P> <A NAME="29353"></A> <A NAME="29354"></A> <P> <HR> <!--Navigation Panel--> <A NAME="tex2html5267" HREF="node185.html"> <IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next.png"></A> <A NAME="tex2html5261" HREF="node182.html"> <IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up.png"></A> <A NAME="tex2html5257" HREF="node183.html"> <IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="prev.png"></A> <A NAME="tex2html5263" HREF="node1.html"> <IMG WIDTH="65" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="contents" SRC="contents.png"></A> <A NAME="tex2html5265" HREF="node256.html"> <IMG WIDTH="43" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="index" SRC="index.png"></A> <BR> <B> Next:</B> <A NAME="tex2html5268" HREF="node185.html">B.2.3 Boundary Conditions for</A> <B> Up:</B> <A NAME="tex2html5262" HREF="node182.html">B.2.2 Gridline and Pixel</A> <B> Previous:</B> <A NAME="tex2html5258" HREF="node183.html">B.2.2.1 Gridline registration</A> <B> <A NAME="tex2html5264" HREF="node1.html">Contents</A></B> <B> <A NAME="tex2html5266" HREF="node256.html">Index</A></B> <!--End of Navigation Panel--> <ADDRESS> Paul Wessel 2010-07-14 </ADDRESS> </BODY> </HTML>