<html>
  <head>
    <meta content="text/html; charset=UTF-8" http-equiv="Content-Type">
  </head>
  <body text="#000000" bgcolor="#FFFFFF">
    <div class="moz-cite-prefix">Hi David,<br>
      <br>
      I'll try vtkImageResize. Thanks.<br>
      <br>
      Best,<br>
      Weiguang<br>
      <br>
      On 11/09/2015 1:48 PM, David Gobbi wrote:<br>
    </div>
    <blockquote
cite="mid:CANwS1=HWif4Odj0uQdV-E4fT+pZKO1oTfQYxEkcFDVoC9GM_iA@mail.gmail.com"
      type="cite">
      <div dir="ltr">Hi Weiguang,
        <div><br>
        </div>
        <div>You can do the image resizing as a preliminary step with
          vtkImageResize, which does efficient band-limited sinc
          interpolation and can do a good job of shrinking the image
          without introducing aliasing artifacts.</div>
        <div><br>
        </div>
        <div>Hopefully someone else will answer your question about
          vtkVolumeTextureMapper3D (I haven't used it in a while).</div>
        <div><br>
        </div>
        <div> - David<br>
          <div class="gmail_extra"><br>
            <div class="gmail_quote">On Fri, Sep 11, 2015 at 11:22 AM,
              Weiguang guan <span dir="ltr"><<a
                  moz-do-not-send="true"
                  href="mailto:guanw@rhpcs.mcmaster.ca" target="_blank">guanw@rhpcs.mcmaster.ca</a>></span>
              wrote:<br>
              <blockquote class="gmail_quote" style="margin:0 0 0
                .8ex;border-left:1px #ccc solid;padding-left:1ex">
                <div text="#000000" bgcolor="#FFFFFF"> Hello VTK users,
                  <br>
                  <br>
                  We develop a viz system using vtkVolumeTextureMapper3D
                  for volume rendering. Recently, we've moved up from
                  v5.1 to v6.2. After that, we notice our viz system has
                  a significant slow-down in rendering speed (compared
                  on the same computer) when volume size is large, say
                  LxWxH ~= 512<sup><span
                      style="display:inline-block;width:0;min-height:0;overflow:hidden">^</span>3</sup>.
                  It can always render small volumes at interactive
                  rate. <br>
                  <br>
                  I know that vtkVolumeTextureMapper3D needs to resample
                  large volume to fit in 128*256*256 (BTW, our data is
                  regular volume data with a single component). But this
                  down-sampling process is not new in 6.2. Are there
                  other changes that cause the performance issue? Does
                  anyone experience the same issue? Thanks. <br>
                  <br>
                  Best, <br>
                  Weiguang</div>
              </blockquote>
            </div>
            <br>
          </div>
        </div>
      </div>
    </blockquote>
    <br>
  </body>
</html>