Hi Naimul, It looks to me that all the intensities from the source imagery are mapping to a large alpha value so little or no alpha blending is taking place.
On the topic of normalization, the transfer function file is 5 fields, I R G B A, where I is the intennity that you wish to map, followed by Red Green Blue Alpha values that are in the range 0.0 to 1.0 for the --tf option. I can't recall off the top of my head whether the input data is renormalized to sit within the 0 to 1 range, but there is certainly option in osgvolume for doing this. osgvolume by default set up a range of shaders to allow you to view the data in different ways. Press the 'v' key to cycle through the standard, light, iso-surface and MIP (maximum internsity projection) rendering. Robert. On Mon, Mar 14, 2011 at 9:19 PM, Naimul Khan <[email protected]> wrote: > Hi Robert, > > Thanks for your quick reply, good to know it can be done with osgVolume. I > will explain the problem I am facing in detail now: > > 1. I have tried to load some dicom images (provided by a doctor here) with > the following command: > > osgvolume --images *.dcm > > The images load without any issues, but the output I get is something like > output_withouttf.jpg attachment. (The opener of this thread got something > similar as I can see). > > 2. Then I tried to play around with the transfer function to generate > something better. I downloaded some sample transfer functions from the > following tutorial (they have a zip file with several sample transfer > functions for bones, brain etc.): > > *link posted in next post* > > Since their example had some parameter like --tf-255 and osgvolume actually > does not have any parameter like this, I converted all the values to be in > between 0 and 1. From this forum I figured out that is how it should be, > please correct me if I am wrong. The color-255.tf and my converted color.tf > both are attached to this post. Then I executed a command as follows: > > osgvolume --images *.dcm --tf color.tf > > And I get an output like the attached output_withtf.jpg. > > I have tried some other color transfer functions too, but all the outputs are > like this. I am guessing it has something to do with the way I am trying to > normalize the transfer function? Please let me know if I am doing anything > wrong. > > ... > > Thank you! > > Cheers, > Naimul > > ------------------ > Read this topic online here: > http://forum.openscenegraph.org/viewtopic.php?p=37610#37610 > > > > > Attachments: > http://forum.openscenegraph.org//files/colortf_205.txt > http://forum.openscenegraph.org//files/color_255tf_364.txt > http://forum.openscenegraph.org//files/output_withtf_110.jpg > http://forum.openscenegraph.org//files/output_withouttf_144.jpg > > > _______________________________________________ > osg-users mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
