[vtkusers] Fwd: non-square image "cropped" after rotate 90º

[Marcos]

Thank you so much, it worked.

Just one thing: after your change, in a multiframe image, when I rotated
it, it was still cropped on one side. I noticed that, switching to the
next/previous, it was corrected (I could the entire image rotated), so my
solution for now is moving to the next frame and inmediatly going back
again.



2015-09-17 0:36 GMT+02:00 David Gobbi <david.gobbi at gmail.com>:

> Hi Marcos,
>
> Changing to SetResliceAxes is simple.  Just do this:
>
>     reslicer->SetResliceAxes(transform->GetMatrix());
>
> Then remove the call to SetOutputExtent().
>
> The output extent should not be the same as the input extent when
> you rotate a rectangular image.
>
> Also, do not set the Extent with the Bounds.  The Bounds and the Extent
> are not the same thing (here the Bounds is measured in millimetres, but
> the Extent is measured in voxels).  It might have worked for you if your
> voxel size was 1mm x 1mm x 1mm, but in general this is not the case.
>
>  - David
>
>
>
> On Wed, Sep 16, 2015 at 4:24 PM, Marcos <fotosentido at gmail.com> wrote:
>
>>
>> Hi,
>>
>> I tried before woth SetResliceAxes, but I didn't get how to use a
>> vtkMatrix4x4 as I said in another post.
>>
>> It was working with SetResliceTransform, until I saw that.
>>
>>
>> I tried to do this:
>>
>> void ViewerWidget::rotateCalculate(int angle, double axis[])
>>
>> {
>>
>>     double bounds[6];
>>
>>     con->GetOutput()->GetBounds(bounds);
>>
>>     double center[3];
>>
>>     center[0] = (bounds[1] + bounds[0]) / 2.0;
>>
>>     center[1] = (bounds[3] + bounds[2]) / 2.0;
>>
>>     center[2] = (bounds[5] + bounds[4]) / 2.0;
>>
>>     transform->Translate(center[0], center[1], center[2]);
>>
>>     transform->RotateWXYZ(angle, axis);
>>
>>     transform->Translate(-center[0], -center[1], -center[2]);
>>
>>     reslicer->SetResliceTransform(transform);
>>
>>
>>     // added this line,
>>
>>     reslicer->SetOutputExtent(bounds[2], bounds[3], bounds[0], bounds[1],
>>
>>             bounds[4], bounds[5]);
>>
>>
>>     reslicer->Update();
>>
>> }
>>
>>
>> I got an exception : read access violation on
>> vtkImageMapToWindowLevelColors::ThreadedRequestData
>> even with square images.
>>
>> The bound values for a non square-image (multiframe):
>> 299.5, 898.5, 214.5, 643.5, 4.5, 13.5
>>
>> The bound values for the square image (multiframe):
>> 127.5, 382.5, 127.5, 382.5, 521.024, 1563.0749
>>
>>
>> 2015-09-16 22:49 GMT+02:00 David Gobbi <david.gobbi at gmail.com>:
>>
>>> On Wed, Sep 16, 2015 at 1:46 PM, Siavash Khallaghi <siavashk at ece.ubc.ca>
>>> wrote:
>>>
>>>> Hi Marcos,
>>>>
>>>> Can you compare the extent of the output of vtkImageReslice against its
>>>> input? My gut feeling is that they are not equal.
>>>>
>>>
>>> I suggest to use SetResliceAxes() (using transform->GetMatrix()) instead
>>> of
>>> SetResliceTransform.  Here is why:
>>>
>>> When you use SetResliceAxes(), vtkImageReslice will transform the input
>>> sampling (i.e. the extent and spacing) so that the output extent is
>>> rotated as
>>> compared to the input extent.
>>>
>>> Another option is to manually set the output extent, with
>>> reslice->SetOutputExtent().
>>>
>>>
>>>
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