vtk TIFF support (Was Re: [vtkusers] How can I open a TIFF file?)

[warozzi at imation.com]

Beware,

As of the nightly version of 2 April, it appears that there is a blend of
both the original TIFF code and new support for the libtiff library.  If
a particular image's TIFF structure is supported by the old code, that
code is used to read the data.  Otherwise, the libtiff code is used, and
in particular the libtiff RGBA interface.  This means that no matter what
the
color space or bit depth of your image is, you'll get out 8-bit RGBA data
For many applications this may be acceptable, but 1-bit images will
consume 32 times the amount of memory necessary.  In my application
with TIFF files in the hundreds of megabites, this is a showstopper.
(This fails even if I try to do an ExtractComponents right after the TIFF
Reader so that there's only an 8x memory expansion, as the failure
occurs in the vtkTIFFReader object.)

I haven't had time to check whether this code blend has changed;
would someone please post a note if the situation has improved?

Regards,
     Bill




                                                                                                                                        
                          Andy Cedilnik                                                                                                 
                          <andy.cedilnik at kit      To: Rocío Sánchez Fernández <rsanfer at neptuno.lpi.tel.uva.es>                          
                          ware.com>               cc: vtkusers at public.kitware.com                                                       
                          Sent by:                Subject:  Re: [vtkusers] How can I open a TIFF file?                                  
                          vtkusers-admin at pub                                                                                            
                          lic.kitware.com                                                                                               
                                                                                                                                        
                                                                                                                                        
                          06/04/2002 07:11                                                                                              
                          AM                                                                                                            
                                                                                                                                        
                                                                                                                                        




If I remember correctly, VTK 3.2 had the old TIFF reader inside
(vtkTIFFReader). It is however limited to only a hand full of TIFF
formats. If you want to be able to open arbitrary TIFF format, I suggest
switching to VTK 4.*.

vtkTIFFReader r
r SetFileName "file.tif"
r Update

                                     Andy

On Tue, 2002-06-04 at 05:53, Rocío Sánchez Fernández wrote:
> Is there any way to open a TIFF file and to get a pointer of the
> luminance of the pixels independently of the NumberOfScalarsComponents? I
> only work with gray-level images, but I have images with 1 and 4
> ScalarComponents...
> I work with VTK 3.2 and tcl/tk on workstation Linux.


_______________________________________________
This is the private VTK discussion list.
Please keep messages on-topic. Check the FAQ at: <
http://public.kitware.com/cgi-bin/vtkfaq>
Follow this link to subscribe/unsubscribe:
http://public.kitware.com/mailman/listinfo/vtkusers