[vtkusers] Extract a slice and save it as jpg/png

[Chris Turner]

Hi David & Bill,

thanks for your patience and your help I appreciate it a lot!  So this
is the code with David's suggestion:

import os
import vtk
import sys


reader=vtk.vtkImageReader()
reader.SetFileName("/tmp/lungROI.vtk")
reader.Update()

lut=vtk.vtkLookupTable()
lut.SetRange(-1024, +4095)

map=vtk.vtkImageMapToColors()
map.SetInput(reader.GetOutput())
map.SetLookupTable(lut)


voi=vtk.vtkExtractVOI()
voi.SetInput(map.GetOutput())
voi.SetVOI(0,0,0,79,146,1)
voi.Update()

writerp=vtk.vtkPNGWriter()
writerp.SetInput(voi.GetOutput())
writerp.SetFileName("/tmp/out.png")
writerp.Write()

print "done"


.... but still no output nor an error message. You can take a look at
the Image here:

http://www.load.to/t8MWurwasf/lungROI.vtk (~10mb)

Thanks Again,
Chris


On Tue, Jul 13, 2010 at 4:38 PM, David Gobbi <david.gobbi at gmail.com> wrote:
> Hi Chris,
>
> This could be an instance of trying to write 16-bit data to a JPEG
> file.  Try adding vtkImageMapToColors with a suitable vtkLookupTable.
>  The Range of the lookup table will have to be set to something
> reasonable for the image, a range of (-1024, +4095) is a good place to
> start and then you can increase or decrease the range in order to get
> the contrast right.
>
>   David
>
>
> On Tue, Jul 13, 2010 at 2:15 PM, Bill Lorensen <bill.lorensen at gmail.com> wrote:
>> Post you entire example. And, if you can post a link to your data...
>>
>> On Tue, Jul 13, 2010 at 3:57 PM, Chris Turner
>> <cturnercomplex at googlemail.com> wrote:
>>> Hi Bill,
>>>
>>> thanks for your answer! But didn't do the trick.
>>> So strange I thought this was a standard question and procedure. And
>>> that there has to be a easy way to do that.
>>>
>>> And why don't I even get a error message or something. Even when I
>>> turn on the debug mode there is nothing suspicious.
>>>
>>> Anybody has another approach?
>>>
>>> Thanks
>>> Chris
>>>
>>> On Mon, Jul 12, 2010 at 10:16 AM, Bill Lorensen <bill.lorensen at gmail.com> wrote:
>>>> Try,
>>>> voi.SetVOI(0,0,0,511,511,0)
>>>>
>>>> On Mon, Jul 12, 2010 at 10:07 AM, Chris Turner
>>>> <cturnercomplex at googlemail.com> wrote:
>>>>> Really? Am I the only one with that problem?
>>>>>
>>>>> On Fri, Jul 9, 2010 at 5:02 PM, Chris Turner
>>>>> <cturnercomplex at googlemail.com> wrote:
>>>>>> Hi Everyone!
>>>>>>
>>>>>> I'm trying to extract a slice from a vtkImageData object and save it as picture.
>>>>>>
>>>>>> That's how I do it:
>>>>>>
>>>>>> voi=vtkExtractVOI()
>>>>>> voi.SetInput(imageData)
>>>>>> voi.SetVOI(0,0,0,512,512,1)
>>>>>> voi.Update()
>>>>>>
>>>>>> writer=vtkJPEGWriter()
>>>>>> writer.SetInput(voi.GetOutput())
>>>>>> writer.SetFileName("slice.jpg")
>>>>>> writer.Write()
>>>>>>
>>>>>> ImageData is 512x512x40 spacing 1,1,1
>>>>>>
>>>>>> The strange thing is I don't get an output nor an error message. So I
>>>>>> think I'm missing something here.... but it can't figure out what.
>>>>>>
>>>>>> So does anybody have an idea or a better solution?
>>>>>>
>>>>>> Thanks
>>>>>> Chris
>>>>>>
>>>>> _______________________________________________
>>>>> 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
>>>>>
>>>>
>>>
>> _______________________________________________
>> 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
>>
>