BUG: Fix GDCM buffer size when written pixel type is different.

Previous value was twice its correct value in itkGDCMSeriesReadImageWriterTest
where the written pixel type is short and the pre-rescaled pixel type is char.

Change-Id: I16537fac89c5937f9c7ec2017c091fba8a896b56
COMP: Disable array above bounds warnings in FixedArray for GCC 4.9.

False positives.

Change-Id: I9ba0a323c628f1ccdf665935fd19212f2bb2b1dc
BUG: Fix out of bounds access for image region size

This patch was detected by the following warning:
/.../SimpleITK-build/ITK-prefix/include/ITK-4.6/itkSize.h: In member
function 'void itk::LabelVotingImageFilter<TInputImage,
TOutputImage>::ThreadedGenerateData(const typename
itk::ImageToImageFilter<TInputImage,
TOutputImage>::OutputImageRegionType&, itk::ThreadIdType) [with
TInputImage = itk::Image<long unsigned int, 3u>, TOutputImage =
itk::Image<long unsigned int, 3u>]':
 /.../SimpleITK-build/ITK-prefix/include/ITK-4.6/itkSize.h:159:
 warning: array subscript is above array bounds

Change-Id: I474492d0654ed91844fac9851877907b41be534a
BUG: Increased OtsuThreshold computation precision

While debugging differences in the Debian 32-bits platform with SSE disable it
was found that the intermediate computations of the variance difference were
getting truncated in some platforms from 80bits floats used in internal FPU
registers, to 64bits ones used in memory. This truncation resulted in
inconsistent results across platforms.

In order to achieve cross-platform consistency, this patch introduces the use
of the "volatile" modifier in the declaration of intermediate computations of
inter-class variance differences. The "volatile" modifier instructs the
compiler not to keep values in the FPU registers, and instead store them in
memory, where they are actually fitted to the IEEE float/double representation.
This change ensures consistency of computation across platforms.

Change-Id: I2aa8833c06bba1bb9a06ef2a00ef4b2512bd6f46
Merge topic 'GCC49AboveBounds1'

07c38084 COMP: Disable array above bounds warnings in FixedArray for GCC 4.9.
BUG: Set output type to unsigned char when writing uchar in GDCMIO test.

In itkGDCMSeriesReadImageWriteTest, the GDCMImageIO is re-used on a writer
that is writing a unsigned char image.  However the ImageIO was originally
used to read an unsigned short image, and writing unsigned char data to an
unsigned short DICOM file is not supported by DICOM.

Use SetInternalComponentType to set the correct internal component type when
writing the unsigned char file.

Change-Id: I5410afc22678990a173e3bcfe578cfc984e16763
Merge topic 'debian32'

b3ca416b BUG: Increased OtsuThreshold computation precision
Merge topic 'GDCMRescalePixelTypes2'

1edae060 BUG: Set output type to unsigned char when writing uchar in GDCMIO test.
ce503c43 BUG: Fix GDCM buffer size when written pixel type is different.
BUG: Add export specification to DCMTKFileReader and utilities

Change-Id: I1ccd7d9a95cf8005abbc0b725bb4daabe891822e
Merge topic 'AddDCMTKFileReaderExportSpecification'

d34bfa4f BUG: Add export specification to DCMTKFileReader and utilities
Merge topic 'FixArrayBoundsForLabelVoting'

4030325b BUG: Fix out of bounds access for image region size