chainer.functions.roi_average_pooling_2d

chainer.functions.roi_average_pooling_2d(x, rois, roi_indices, outsize, spatial_scale)[source]

Spatial Region of Interest (ROI) average pooling function.

This function acts similarly to average_pooling_2d(), but it computes the average of input spatial patch for each channel with the region of interest.

Parameters
  • x (Variable) – Input variable. The shape is expected to be 4 dimensional: (n: batch, c: channel, h, height, w: width).

  • rois (Variable) – Input roi variable. The shape is expected to be (n: data size, 4), and each datum is set as below: (y_min, x_min, y_max, x_max).

  • roi_indices (Variable) – Input roi variable. The shape is expected to be (n: data size, ).

  • outsize ((int, int) or int) – Expected output size after pooled (height, width). outsize=o and outsize=(o, o) are equivalent.

  • spatial_scale (float) – Scale of the roi is resized.

Returns

Output variable.

Return type

Variable

See the original paper proposing ROIPooling: Fast R-CNN.