Spatial Region of Interest (ROI) pooling function.
This function acts similarly to :class:`~functions.MaxPooling2D`, but
it computes the maximum of input spatial patch for each channel
with the region of interest.
Args:
x (~chainer.Variable): Input variable.
rois (~chainer.Variable): Input roi variable.
outh (int): Height of output image after pooled.
outw (int): Width of output image after pooled.
spatial_scale (float): Scale of the roi is resized.
Returns:
~chainer.Variable: Ouptut variable.
See the original paper proposing ROIPooling:
`Fast R-CNN <http://arxiv.org/abs/1504.08083>`_.
Definition at line 313 of file roi_pooling_2d.py.