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872b0a0 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 | import tensorflow as tf
import tensorflow.contrib.slim as slim
import numpy as np
from .augment import random_affine, random_photometric
from .flow_util import flow_to_color
from .util import resize_area, resize_bilinear
from .losses import compute_losses, create_border_mask
from .util import downsample
from .image_warp import image_warp
from .flownet import flownet, FLOW_SCALE
# REGISTER ALL POSSIBLE LOSS TERMS
LOSSES = ['occ', 'sym', 'fb', 'grad', 'ternary', 'photo', 'smooth_1st', 'smooth_2nd']
def _track_loss(op, name):
tf.add_to_collection('losses', tf.identity(op, name=name))
def _track_image(op, name):
name = 'train/' + name
tf.add_to_collection('train_images', tf.identity(op, name=name))
def unsupervised_loss(batch, params, normalization=None, augment=True,
return_flow=False):
channel_mean = tf.constant(normalization[0]) / 255.0
im1, im2 = batch
im1 = im1 / 255.0
im2 = im2 / 255.0
im_shape = tf.shape(im1)[1:3]
# -------------------------------------------------------------------------
# Data & mask augmentation
border_mask = create_border_mask(im1, 0.1)
if augment:
im1_geo, im2_geo, border_mask_global = random_affine(
[im1, im2, border_mask],
horizontal_flipping=True,
min_scale=0.9, max_scale=1.1
)
# augment locally
im2_geo, border_mask_local = random_affine(
[im2_geo, border_mask],
min_scale=0.9, max_scale=1.1
)
border_mask = border_mask_local * border_mask_global
im1_photo, im2_photo = random_photometric(
[im1_geo, im2_geo],
noise_stddev=0.04, min_contrast=-0.3, max_contrast=0.3,
brightness_stddev=0.02, min_colour=0.9, max_colour=1.1,
min_gamma=0.7, max_gamma=1.5)
_track_image(im1_photo, 'augmented1')
_track_image(im2_photo, 'augmented2')
else:
im1_geo, im2_geo = im1, im2
im1_photo, im2_photo = im1, im2
# Images for loss comparisons with values in [0, 1] (scale to original using * 255)
im1_norm = im1_geo
im2_norm = im2_geo
# Images for neural network input with mean-zero values in [-1, 1]
im1_photo = im1_photo - channel_mean
im2_photo = im2_photo - channel_mean
flownet_spec = params.get('flownet', 'S')
full_resolution = params.get('full_res')
train_all = params.get('train_all')
flows_fw, flows_bw = flownet(im1_photo, im2_photo,
flownet_spec=flownet_spec,
full_resolution=full_resolution,
backward_flow=True,
train_all=train_all)
flows_fw = flows_fw[-1]
flows_bw = flows_bw[-1]
# -------------------------------------------------------------------------
# Losses
layer_weights = [12.7, 4.35, 3.9, 3.4, 1.1]
layer_patch_distances = [3, 2, 2, 1, 1]
if full_resolution:
layer_weights = [12.7, 5.5, 5.0, 4.35, 3.9, 3.4, 1.1]
layer_patch_distances = [3, 3] + layer_patch_distances
im1_s = im1_norm
im2_s = im2_norm
mask_s = border_mask
final_flow_scale = FLOW_SCALE * 4
final_flow_fw = flows_fw[0] * final_flow_scale
final_flow_bw = flows_bw[0] * final_flow_scale
else:
im1_s = downsample(im1_norm, 4)
im2_s = downsample(im2_norm, 4)
mask_s = downsample(border_mask, 4)
final_flow_scale = FLOW_SCALE
final_flow_fw = tf.image.resize_bilinear(flows_fw[0], im_shape) * final_flow_scale * 4
final_flow_bw = tf.image.resize_bilinear(flows_bw[0], im_shape) * final_flow_scale * 4
combined_losses = dict()
combined_loss = 0.0
for loss in LOSSES:
combined_losses[loss] = 0.0
if params.get('pyramid_loss'):
flow_enum = enumerate(zip(flows_fw, flows_bw))
else:
flow_enum = [(0, (flows_fw[0], flows_bw[0]))]
for i, flow_pair in flow_enum:
layer_name = "loss" + str(i + 2)
flow_scale = final_flow_scale / (2 ** i)
with tf.variable_scope(layer_name):
layer_weight = layer_weights[i]
flow_fw_s, flow_bw_s = flow_pair
mask_occlusion = params.get('mask_occlusion', '')
assert mask_occlusion in ['fb', 'disocc', '']
losses = compute_losses(im1_s, im2_s,
flow_fw_s * flow_scale, flow_bw_s * flow_scale,
border_mask=mask_s if params.get('border_mask') else None,
mask_occlusion=mask_occlusion,
data_max_distance=layer_patch_distances[i])
layer_loss = 0.0
for loss in LOSSES:
weight_name = loss + '_weight'
if params.get(weight_name):
_track_loss(losses[loss], loss)
layer_loss += params[weight_name] * losses[loss]
combined_losses[loss] += layer_weight * losses[loss]
combined_loss += layer_weight * layer_loss
im1_s = downsample(im1_s, 2)
im2_s = downsample(im2_s, 2)
mask_s = downsample(mask_s, 2)
regularization_loss = tf.losses.get_regularization_loss()
final_loss = combined_loss + regularization_loss
_track_loss(final_loss, 'loss/combined')
for loss in LOSSES:
_track_loss(combined_losses[loss], 'loss/' + loss)
weight_name = loss + '_weight'
if params.get(weight_name):
weight = tf.identity(params[weight_name], name='weight/' + loss)
tf.add_to_collection('params', weight)
if not return_flow:
return final_loss
return final_loss, final_flow_fw, final_flow_bw
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