The DCNPooling class implements deformable ROI pooling (V2), wrapping offset and mask calculations. It requires an input tensor and a tensor of ROIs.
ROI Format:
ROIs should be a tensor of shape (N, 5) where the columns are [batch_index, x, y, x + w, y + h].
Usage Example:
from dcn_v2 import DCNPooling
import torch
input = torch.randn(2, 32, 64, 64).cuda()
# batch_inds, x, y, w, h
batch_inds = torch.randint(2, (20, 1)).cuda().float()
x = torch.randint(256, (20, 1)).cuda().float()
y = torch.randint(256, (20, 1)).cuda().float()
w = torch.randint(64, (20, 1)).cuda().float()
h = torch.randint(64, (20, 1)).cuda().float()
# Concatenate to form ROIs: [batch_idx, x1, y1, x2, y2]
rois = torch.cat((batch_inds, x, y, x + w, y + h), dim=1)
# Initialize DCNPooling
dpooling = DCNPooling(spatial_scale=1.0 / 4,
pooled_size=7,
output_dim=32,
no_trans=False,
group_size=1,
trans_std=0.1).cuda()
dout = dpooling(input, rois)
from dcn_v2 import DCNPooling
input = torch.randn(2, 32, 64, 64).cuda()
batch_inds = torch.randint(2, (20, 1)).cuda().float()
x = torch.randint(256, (20, 1)).cuda().float()
y = torch.randint(256, (20, 1)).cuda().float()
w = torch.randint(64, (20, 1)).cuda().float()
h = torch.randint(64, (20, 1)).cuda().float()
rois = torch.cat((batch_inds, x, y, x + w, y + h), dim=1)
# mdformable pooling (V2)
# wrap all things (offset and mask) in DCNPooling
dpooling = DCNPooling(spatial_scale=1.0 / 4,
pooled_size=7,
output_dim=32,
no_trans=False,
group_size=1,
trans_std=0.1).cuda()
dout = dpooling(input, rois)