[vtkusers] vtkImageColorViewer and slice orientation

Mon Nov 30 17:37:01 EST 2009

It hardly makes any difference.  If you use one reslice, then it has
to output several slices.  If you use multiple reslices, then each one
only produces a single slice.  Overall, the amount of data in memory
is the same.

    David

On Mon, Nov 30, 2009 at 3:30 PM, Lic. José M. Rodriguez Bacallao
<jmrbcu at gmail.com> wrote:
> last question for today, how memory hungry is that setup (one anything
> per slice)?
>
> On 11/30/09, David Gobbi <david.gobbi at gmail.com> wrote:
>> On Mon, Nov 30, 2009 at 2:49 PM, Lic. José M. Rodriguez Bacallao
>> <jmrbcu at gmail.com> wrote:
>>> reader.GetOutput().Update() is not the same that reader.Update()?
>>
>> When VTK 5.0 was released, data.Update() did a little bit extra that
>> algorithm.Update() did not do, i.e. in VTK 5.0 the pipeline was newly
>> designed and had some bugs.  Now the pipeline bugs are fixed, but I
>> still always call update on data out of habit.
>>
>>
>>> if U have a renderer per slice, why to have a reslice for every render
>>> and not just one?
>>
>> Because I find that the easiest way to use vtkImageReslice is to make
>> it output just one slice.  It is just my preference, in other words.
>>
>>
>>> How do I achieve that if I change the window/level in a renderer, all
>>> images in the 4x4 configuration get updated with the same
>>> window/level?
>>
>> Easy.  Use the same vtkLookupTable for all images.  In your data
>> pipeline, use vtkImageMapToColors() to color the data.  I cannot help
>> you with vtkImageColorViewer because I never use that class.
>>
>>     David
>>
>>
>>> On 11/30/09, David Gobbi <david.gobbi at gmail.com> wrote:
>>>> Usually I use a separate renderer for each slice.  This also means a
>>>> separate reslice, image actor, etc.
>>>>
>>>> For this to work efficiently, you must force the reader to read all
>>>> the whole dicom series, like this:
>>>>
>>>> reader.GetOutput().Update()
>>>>
>>>> If you don't do this, then the reader will only read one slice at a
>>>> time, so if you are displaying 4x4 then it will go to the disk 16
>>>> times on every render.  By calling update on the the reader, you force
>>>> the whole series into memory.
>>>>
>>>>     David
>>>>
>>>>
>>>> On Mon, Nov 30, 2009 at 1:58 PM, Lic. José M. Rodriguez Bacallao
>>>> <jmrbcu at gmail.com> wrote:
>>>>> thanks, and another question:
>>>>>
>>>>> I need to display the images in a dicom serie in several
>>>>> configurations: just one image, 2 images side by side, 2x2 images and
>>>>> so on. Which is the recommended way to display those configurations in
>>>>> a render window, with several renderers or with several image actors?
>>>>>
>>>>> On 11/30/09, David Gobbi <david.gobbi at gmail.com> wrote:
>>>>>> On Mon, Nov 30, 2009 at 1:11 PM, Lic. José M. Rodriguez Bacallao
>>>>>> <jmrbcu at gmail.com> wrote:
>>>>>>> yes, thanks, in fact this is my pattern example but, in this example
>>>>>>> the sagital view is flipped, why is that?
>>>>>>
>>>>>> You are complaining because the head is facing right instead of facing
>>>>>> left??  It is still sagittal.
>>>>>>
>>>>>>> PS: So, to use ImageReslice for an dicom image viewer is not a
>>>>>>> problem?
>>>>>>
>>>>>> No problem at all.  Plenty of people use it for dicom.  The only
>>>>>> restrictions are the following:
>>>>>>
>>>>>> 1) the spacing must be constant
>>>>>>
>>>>>> 2) the gantry must not be tilted
>>>>>>
>>>>>> These restrictions are true for all vtkImageData.  Fortunately, CT and
>>>>>> MRI almost always use constant slice spacing, so that is never a
>>>>>> problem.  CT gantry tilt can be fairly common, though, so any dicom
>>>>>> image viewer should check for it.  MR images never have gantry tilt.
>>>>>>
>>>>>>     David
>>>>>>
>>>>>>
>>>>>>>
>>>>>>> On 11/30/09, David Gobbi <david.gobbi at gmail.com> wrote:
>>>>>>>> I didn't give the full path for the example in my last email.  Here
>>>>>>>> it
>>>>>>>> is:
>>>>>>>>
>>>>>>>> VTK/Examples/ImageProcessing/Python/ImageSlicing.py
>>>>>>>>
>>>>>>>>    David
>>>>>>>>
>>>>>>>>
>>>>>>>> On Mon, Nov 30, 2009 at 12:25 PM, David Gobbi <david.gobbi at gmail.com>
>>>>>>>> wrote:
>>>>>>>>> Because no-one has contributed a reslicng image viewer to VTK yet.
>>>>>>>>>  I
>>>>>>>>> would like to do so myself, but I don't know when I will have the
>>>>>>>>> time.
>>>>>>>>>
>>>>>>>>> I did submit a python reslicing example to VTK that you might find
>>>>>>>>> useful:
>>>>>>>>>
>>>>>>>>> VTK/Examples/Python/ImageSlicing.py
>>>>>>>>>
>>>>>>>>>   David
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> On Mon, Nov 30, 2009 at 11:45 AM, Lic. José M. Rodriguez Bacallao
>>>>>>>>> <jmrbcu at gmail.com> wrote:
>>>>>>>>>> why is that?
>>>>>>>>>>
>>>>>>>>>> On 11/30/09, David Gobbi <david.gobbi at gmail.com> wrote:
>>>>>>>>>>> The only class that uses vtkImageReslice for image viewing is
>>>>>>>>>>> vtkImagePlaneWidget, you can try it to see if it is suitable for
>>>>>>>>>>> your
>>>>>>>>>>> application.  That is the closest thing to a generic reslicing
>>>>>>>>>>> image
>>>>>>>>>>> viewer that VTK has.
>>>>>>>>>>>
>>>>>>>>>>>    David
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> On Mon, Nov 30, 2009 at 9:20 AM, Lic. José M. Rodriguez Bacallao
>>>>>>>>>>> <jmrbcu at gmail.com> wrote:
>>>>>>>>>>>> why vtkImageColorViewer(I think that vtkImageViewer2 too) doesn't
>>>>>>>>>>>> use
>>>>>>>>>>>> vtkImageReslice for changing the slice orientation (axial,
>>>>>>>>>>>> sagital
>>>>>>>>>>>> and
>>>>>>>>>>>> coronal)? I am just curious!!!
>>>>>>>>>>>>
>>>>>>>>>>>> --
>>>>>>>>>>>> Lic. José M. Rodriguez Bacallao
>>>>>>>>>>>> Centro de Biofisica Medica
>>>>>>>>>>>> -----------------------------------------------------------------
>>>>>>>>>>>> Todos somos muy ignorantes, lo que ocurre es que no todos
>>>>>>>>>>>> ignoramos
>>>>>>>>>>>> lo
>>>>>>>>>>>> mismo.
>>>>>>>>>>>>
>>>>>>>>>>>> Recuerda: El arca de Noe fue construida por aficionados, el
>>>>>>>>>>>> titanic
>>>>>>>>>>>> por profesionales
>>>>>>>>>>>> -----------------------------------------------------------------
>>>>>>>>>>>> _______________________________________________
>>>>>>>>>>>> Powered by www.kitware.com
>>>>>>>>>>>>
>>>>>>>>>>>> Visit other Kitware open-source projects at
>>>>>>>>>>>> http://www.kitware.com/opensource/opensource.html
>>>>>>>>>>>>
>>>>>>>>>>>> Please keep messages on-topic and check the VTK FAQ at:
>>>>>>>>>>>> http://www.vtk.org/Wiki/VTK_FAQ
>>>>>>>>>>>>
>>>>>>>>>>>> Follow this link to subscribe/unsubscribe:
>>>>>>>>>>>> http://www.vtk.org/mailman/listinfo/vtkusers
>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> --
>>>>>>>>>> Lic. José M. Rodriguez Bacallao
>>>>>>>>>> Centro de Biofisica Medica
>>>>>>>>>> -----------------------------------------------------------------
>>>>>>>>>> Todos somos muy ignorantes, lo que ocurre es que no todos ignoramos
>>>>>>>>>> lo
>>>>>>>>>> mismo.
>>>>>>>>>>
>>>>>>>>>> Recuerda: El arca de Noe fue construida por aficionados, el titanic
>>>>>>>>>> por profesionales
>>>>>>>>>> -----------------------------------------------------------------
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> --
>>>>>>> Lic. José M. Rodriguez Bacallao
>>>>>>> Centro de Biofisica Medica
>>>>>>> -----------------------------------------------------------------
>>>>>>> Todos somos muy ignorantes, lo que ocurre es que no todos ignoramos lo
>>>>>>> mismo.
>>>>>>>
>>>>>>> Recuerda: El arca de Noe fue construida por aficionados, el titanic
>>>>>>> por profesionales
>>>>>>> -----------------------------------------------------------------
>>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Lic. José M. Rodriguez Bacallao
>>>>> Centro de Biofisica Medica
>>>>> -----------------------------------------------------------------
>>>>> Todos somos muy ignorantes, lo que ocurre es que no todos ignoramos lo
>>>>> mismo.
>>>>>
>>>>> Recuerda: El arca de Noe fue construida por aficionados, el titanic
>>>>> por profesionales
>>>>> -----------------------------------------------------------------
>>>>>
>>>>
>>>
>>>
>>> --
>>> Lic. José M. Rodriguez Bacallao
>>> Centro de Biofisica Medica
>>> -----------------------------------------------------------------
>>> Todos somos muy ignorantes, lo que ocurre es que no todos ignoramos lo
>>> mismo.
>>>
>>> Recuerda: El arca de Noe fue construida por aficionados, el titanic
>>> por profesionales
>>> -----------------------------------------------------------------
>>>
>>
>
>
> --
> Lic. José M. Rodriguez Bacallao
> Centro de Biofisica Medica
> -----------------------------------------------------------------
> Todos somos muy ignorantes, lo que ocurre es que no todos ignoramos lo mismo.
>
> Recuerda: El arca de Noe fue construida por aficionados, el titanic
> por profesionales
> -----------------------------------------------------------------
>