import torch
import torch.nn as nn
import torch.nn.functional as F
from .submodules import UpSampleBN, UpSampleGN, norm_normalize, sample_points
class Decoder(nn.Module):
def __init__(self, args):
super(Decoder, self).__init__()
# hyper-parameter for sampling
self.sampling_ratio = args.sampling_ratio
self.importance_ratio = args.importance_ratio
# feature-map
self.conv2 = nn.Conv2d(2048, 2048, kernel_size=1, stride=1, padding=0)
if args.architecture == 'BN':
self.up1 = UpSampleBN(skip_input=2048 + 176, output_features=1024)
self.up2 = UpSampleBN(skip_input=1024 + 64, output_features=512)
self.up3 = UpSampleBN(skip_input=512 + 40, output_features=256)
self.up4 = UpSampleBN(skip_input=256 + 24, output_features=128)
elif args.architecture == 'GN':
self.up1 = UpSampleGN(skip_input=2048 + 176, output_features=1024)
self.up2 = UpSampleGN(skip_input=1024 + 64, output_features=512)
self.up3 = UpSampleGN(skip_input=512 + 40, output_features=256)
self.up4 = UpSampleGN(skip_input=256 + 24, output_features=128)
else:
raise Exception('invalid architecture')
# produces 1/8 res output
self.out_conv_res8 = nn.Conv2d(512, 4, kernel_size=3, stride=1, padding=1)
# produces 1/4 res output
self.out_conv_res4 = nn.Sequential(
nn.Conv1d(512 + 4, 128, kernel_size=1), nn.ReLU(),
nn.Conv1d(128, 128, kernel_size=1), nn.ReLU(),
nn.Conv1d(128, 128, kernel_size=1), nn.ReLU(),
nn.Conv1d(128, 4, kernel_size=1),
)
# produces 1/2 res output
self.out_conv_res2 = nn.Sequential(
nn.Conv1d(256 + 4, 128, kernel_size=1), nn.ReLU(),
nn.Conv1d(128, 128, kernel_size=1), nn.ReLU(),
nn.Conv1d(128, 128, kernel_size=1), nn.ReLU(),
nn.Conv1d(128, 4, kernel_size=1),
)
# produces 1/1 res output
self.out_conv_res1 = nn.Sequential(
nn.Conv1d(128 + 4, 128, kernel_size=1), nn.ReLU(),
nn.Conv1d(128, 128, kernel_size=1), nn.ReLU(),
nn.Conv1d(128, 128, kernel_size=1), nn.ReLU(),
nn.Conv1d(128, 4, kernel_size=1),
)
def forward(self, features, gt_norm_mask=None, mode='test'):
x_block0, x_block1, x_block2, x_block3, x_block4 = features[4], features[5], features[6], features[8], features[11]
# generate feature-map
x_d0 = self.conv2(x_block4) # x_d0 : [2, 2048, 15, 20] 1/32 res
x_d1 = self.up1(x_d0, x_block3) # x_d1 : [2, 1024, 30, 40] 1/16 res
x_d2 = self.up2(x_d1, x_block2) # x_d2 : [2, 512, 60, 80] 1/8 res
x_d3 = self.up3(x_d2, x_block1) # x_d3: [2, 256, 120, 160] 1/4 res
x_d4 = self.up4(x_d3, x_block0) # x_d4: [2, 128, 240, 320] 1/2 res
# 1/8 res output
out_res8 = self.out_conv_res8(x_d2) # out_res8: [2, 4, 60, 80] 1/8 res output
out_res8 = norm_normalize(out_res8) # out_res8: [2, 4, 60, 80] 1/8 res output
################################################################################################################
# out_res4
################################################################################################################
if mode == 'train':
# upsampling ... out_res8: [2, 4, 60, 80] -> out_res8_res4: [2, 4, 120, 160]
out_res8_res4 = F.interpolate(out_res8, scale_factor=2, mode='bilinear', align_corners=True)
B, _, H, W = out_res8_res4.shape
# samples: [B, 1, N, 2]
point_coords_res4, rows_int, cols_int = sample_points(out_res8_res4.detach(), gt_norm_mask,
sampling_ratio=self.sampling_ratio,
beta=self.importance_ratio)
# output (needed for evaluation / visualization)
out_res4 = out_res8_res4
# grid_sample feature-map
feat_res4 = F.grid_sample(x_d2, point_coords_res4, mode='bilinear', align_corners=True) # (B, 512, 1, N)
init_pred = F.grid_sample(out_res8, point_coords_res4, mode='bilinear', align_corners=True) # (B, 4, 1, N)
feat_res4 = torch.cat([feat_res4, init_pred], dim=1) # (B, 512+4, 1, N)
# prediction (needed to compute loss)
samples_pred_res4 = self.out_conv_res4(feat_res4[:, :, 0, :]) # (B, 4, N)
samples_pred_res4 = norm_normalize(samples_pred_res4) # (B, 4, N) - normalized
for i in range(B):
out_res4[i, :, rows_int[i, :], cols_int[i, :]] = samples_pred_res4[i, :, :]
else:
# grid_sample feature-map
feat_map = F.interpolate(x_d2, scale_factor=2, mode='bilinear', align_corners=True)
init_pred = F.interpolate(out_res8, scale_factor=2, mode='bilinear', align_corners=True)
feat_map = torch.cat([feat_map, init_pred], dim=1) # (B, 512+4, H, W)
B, _, H, W = feat_map.shape
# try all pixels
out_res4 = self.out_conv_res4(feat_map.view(B, 512 + 4, -1)) # (B, 4, N)
out_res4 = norm_normalize(out_res4) # (B, 4, N) - normalized
out_res4 = out_res4.view(B, 4, H, W)
samples_pred_res4 = point_coords_res4 = None
################################################################################################################
# out_res2
################################################################################################################
if mode == 'train':
# upsampling ... out_res4: [2, 4, 120, 160] -> out_res4_res2: [2, 4, 240, 320]
out_res4_res2 = F.interpolate(out_res4, scale_factor=2, mode='bilinear', align_corners=True)
B, _, H, W = out_res4_res2.shape
# samples: [B, 1, N, 2]
point_coords_res2, rows_int, cols_int = sample_points(out_res4_res2.detach(), gt_norm_mask,
sampling_ratio=self.sampling_ratio,
beta=self.importance_ratio)
# output (needed for evaluation / visualization)
out_res2 = out_res4_res2
# grid_sample feature-map
feat_res2 = F.grid_sample(x_d3, point_coords_res2, mode='bilinear', align_corners=True) # (B, 256, 1, N)
init_pred = F.grid_sample(out_res4, point_coords_res2, mode='bilinear', align_corners=True) # (B, 4, 1, N)
feat_res2 = torch.cat([feat_res2, init_pred], dim=1) # (B, 256+4, 1, N)
# prediction (needed to compute loss)
samples_pred_res2 = self.out_conv_res2(feat_res2[:, :, 0, :]) # (B, 4, N)
samples_pred_res2 = norm_normalize(samples_pred_res2) # (B, 4, N) - normalized
for i in range(B):
out_res2[i, :, rows_int[i, :], cols_int[i, :]] = samples_pred_res2[i, :, :]
else:
# grid_sample feature-map
feat_map = F.interpolate(x_d3, scale_factor=2, mode='bilinear', align_corners=True)
init_pred = F.interpolate(out_res4, scale_factor=2, mode='bilinear', align_corners=True)
feat_map = torch.cat([feat_map, init_pred], dim=1) # (B, 512+4, H, W)
B, _, H, W = feat_map.shape
out_res2 = self.out_conv_res2(feat_map.view(B, 256 + 4, -1)) # (B, 4, N)
out_res2 = norm_normalize(out_res2) # (B, 4, N) - normalized
out_res2 = out_res2.view(B, 4, H, W)
samples_pred_res2 = point_coords_res2 = None
################################################################################################################
# out_res1
################################################################################################################
if mode == 'train':
# upsampling ... out_res4: [2, 4, 120, 160] -> out_res4_res2: [2, 4, 240, 320]
out_res2_res1 = F.interpolate(out_res2, scale_factor=2, mode='bilinear', align_corners=True)
B, _, H, W = out_res2_res1.shape
# samples: [B, 1, N, 2]
point_coords_res1, rows_int, cols_int = sample_points(out_res2_res1.detach(), gt_norm_mask,
sampling_ratio=self.sampling_ratio,
beta=self.importance_ratio)
# output (needed for evaluation / visualization)
out_res1 = out_res2_res1
# grid_sample feature-map
feat_res1 = F.grid_sample(x_d4, point_coords_res1, mode='bilinear', align_corners=True) # (B, 128, 1, N)
init_pred = F.grid_sample(out_res2, point_coords_res1, mode='bilinear', align_corners=True) # (B, 4, 1, N)
feat_res1 = torch.cat([feat_res1, init_pred], dim=1) # (B, 128+4, 1, N)
# prediction (needed to compute loss)
samples_pred_res1 = self.out_conv_res1(feat_res1[:, :, 0, :]) # (B, 4, N)
samples_pred_res1 = norm_normalize(samples_pred_res1) # (B, 4, N) - normalized
for i in range(B):
out_res1[i, :, rows_int[i, :], cols_int[i, :]] = samples_pred_res1[i, :, :]
else:
# grid_sample feature-map
feat_map = F.interpolate(x_d4, scale_factor=2, mode='bilinear', align_corners=True)
init_pred = F.interpolate(out_res2, scale_factor=2, mode='bilinear', align_corners=True)
feat_map = torch.cat([feat_map, init_pred], dim=1) # (B, 512+4, H, W)
B, _, H, W = feat_map.shape
out_res1 = self.out_conv_res1(feat_map.view(B, 128 + 4, -1)) # (B, 4, N)
out_res1 = norm_normalize(out_res1) # (B, 4, N) - normalized
out_res1 = out_res1.view(B, 4, H, W)
samples_pred_res1 = point_coords_res1 = None
return [out_res8, out_res4, out_res2, out_res1], \
[out_res8, samples_pred_res4, samples_pred_res2, samples_pred_res1], \
[None, point_coords_res4, point_coords_res2, point_coords_res1]