PulseFocusPlatform/ppdet/modeling/tests/test_yolov3_loss.py

415 lines
15 KiB
Python

# Copyright (c) 2018 PaddlePaddle Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from __future__ import division
import unittest
import paddle
from paddle import fluid
# add python path of PadleDetection to sys.path
import os
import sys
parent_path = os.path.abspath(os.path.join(__file__, *(['..'] * 4)))
if parent_path not in sys.path:
sys.path.append(parent_path)
from ppdet.modeling.losses import YOLOv3Loss
from ppdet.data.transform.op_helper import jaccard_overlap
import numpy as np
def _split_ioup(output, an_num, num_classes):
"""
Split output feature map to output, predicted iou
along channel dimension
"""
ioup = fluid.layers.slice(output, axes=[1], starts=[0], ends=[an_num])
ioup = fluid.layers.sigmoid(ioup)
oriout = fluid.layers.slice(
output, axes=[1], starts=[an_num], ends=[an_num * (num_classes + 6)])
return (ioup, oriout)
def _split_output(output, an_num, num_classes):
"""
Split output feature map to x, y, w, h, objectness, classification
along channel dimension
"""
x = fluid.layers.strided_slice(
output,
axes=[1],
starts=[0],
ends=[output.shape[1]],
strides=[5 + num_classes])
y = fluid.layers.strided_slice(
output,
axes=[1],
starts=[1],
ends=[output.shape[1]],
strides=[5 + num_classes])
w = fluid.layers.strided_slice(
output,
axes=[1],
starts=[2],
ends=[output.shape[1]],
strides=[5 + num_classes])
h = fluid.layers.strided_slice(
output,
axes=[1],
starts=[3],
ends=[output.shape[1]],
strides=[5 + num_classes])
obj = fluid.layers.strided_slice(
output,
axes=[1],
starts=[4],
ends=[output.shape[1]],
strides=[5 + num_classes])
clss = []
stride = output.shape[1] // an_num
for m in range(an_num):
clss.append(
fluid.layers.slice(
output,
axes=[1],
starts=[stride * m + 5],
ends=[stride * m + 5 + num_classes]))
cls = fluid.layers.transpose(
fluid.layers.stack(
clss, axis=1), perm=[0, 1, 3, 4, 2])
return (x, y, w, h, obj, cls)
def _split_target(target):
"""
split target to x, y, w, h, objectness, classification
along dimension 2
target is in shape [N, an_num, 6 + class_num, H, W]
"""
tx = target[:, :, 0, :, :]
ty = target[:, :, 1, :, :]
tw = target[:, :, 2, :, :]
th = target[:, :, 3, :, :]
tscale = target[:, :, 4, :, :]
tobj = target[:, :, 5, :, :]
tcls = fluid.layers.transpose(target[:, :, 6:, :, :], perm=[0, 1, 3, 4, 2])
tcls.stop_gradient = True
return (tx, ty, tw, th, tscale, tobj, tcls)
def _calc_obj_loss(output, obj, tobj, gt_box, batch_size, anchors, num_classes,
downsample, ignore_thresh, scale_x_y):
# A prediction bbox overlap any gt_bbox over ignore_thresh,
# objectness loss will be ignored, process as follows:
# 1. get pred bbox, which is same with YOLOv3 infer mode, use yolo_box here
# NOTE: img_size is set as 1.0 to get noramlized pred bbox
bbox, prob = fluid.layers.yolo_box(
x=output,
img_size=fluid.layers.ones(
shape=[batch_size, 2], dtype="int32"),
anchors=anchors,
class_num=num_classes,
conf_thresh=0.,
downsample_ratio=downsample,
clip_bbox=False,
scale_x_y=scale_x_y)
# 2. split pred bbox and gt bbox by sample, calculate IoU between pred bbox
# and gt bbox in each sample
if batch_size > 1:
preds = fluid.layers.split(bbox, batch_size, dim=0)
gts = fluid.layers.split(gt_box, batch_size, dim=0)
else:
preds = [bbox]
gts = [gt_box]
probs = [prob]
ious = []
for pred, gt in zip(preds, gts):
def box_xywh2xyxy(box):
x = box[:, 0]
y = box[:, 1]
w = box[:, 2]
h = box[:, 3]
return fluid.layers.stack(
[
x - w / 2.,
y - h / 2.,
x + w / 2.,
y + h / 2.,
], axis=1)
pred = fluid.layers.squeeze(pred, axes=[0])
gt = box_xywh2xyxy(fluid.layers.squeeze(gt, axes=[0]))
ious.append(fluid.layers.iou_similarity(pred, gt))
iou = fluid.layers.stack(ious, axis=0)
# 3. Get iou_mask by IoU between gt bbox and prediction bbox,
# Get obj_mask by tobj(holds gt_score), calculate objectness loss
max_iou = fluid.layers.reduce_max(iou, dim=-1)
iou_mask = fluid.layers.cast(max_iou <= ignore_thresh, dtype="float32")
output_shape = fluid.layers.shape(output)
an_num = len(anchors) // 2
iou_mask = fluid.layers.reshape(iou_mask, (-1, an_num, output_shape[2],
output_shape[3]))
iou_mask.stop_gradient = True
# NOTE: tobj holds gt_score, obj_mask holds object existence mask
obj_mask = fluid.layers.cast(tobj > 0., dtype="float32")
obj_mask.stop_gradient = True
# For positive objectness grids, objectness loss should be calculated
# For negative objectness grids, objectness loss is calculated only iou_mask == 1.0
loss_obj = fluid.layers.sigmoid_cross_entropy_with_logits(obj, obj_mask)
loss_obj_pos = fluid.layers.reduce_sum(loss_obj * tobj, dim=[1, 2, 3])
loss_obj_neg = fluid.layers.reduce_sum(
loss_obj * (1.0 - obj_mask) * iou_mask, dim=[1, 2, 3])
return loss_obj_pos, loss_obj_neg
def fine_grained_loss(output,
target,
gt_box,
batch_size,
num_classes,
anchors,
ignore_thresh,
downsample,
scale_x_y=1.,
eps=1e-10):
an_num = len(anchors) // 2
x, y, w, h, obj, cls = _split_output(output, an_num, num_classes)
tx, ty, tw, th, tscale, tobj, tcls = _split_target(target)
tscale_tobj = tscale * tobj
scale_x_y = scale_x_y
if (abs(scale_x_y - 1.0) < eps):
loss_x = fluid.layers.sigmoid_cross_entropy_with_logits(
x, tx) * tscale_tobj
loss_x = fluid.layers.reduce_sum(loss_x, dim=[1, 2, 3])
loss_y = fluid.layers.sigmoid_cross_entropy_with_logits(
y, ty) * tscale_tobj
loss_y = fluid.layers.reduce_sum(loss_y, dim=[1, 2, 3])
else:
dx = scale_x_y * fluid.layers.sigmoid(x) - 0.5 * (scale_x_y - 1.0)
dy = scale_x_y * fluid.layers.sigmoid(y) - 0.5 * (scale_x_y - 1.0)
loss_x = fluid.layers.abs(dx - tx) * tscale_tobj
loss_x = fluid.layers.reduce_sum(loss_x, dim=[1, 2, 3])
loss_y = fluid.layers.abs(dy - ty) * tscale_tobj
loss_y = fluid.layers.reduce_sum(loss_y, dim=[1, 2, 3])
# NOTE: we refined loss function of (w, h) as L1Loss
loss_w = fluid.layers.abs(w - tw) * tscale_tobj
loss_w = fluid.layers.reduce_sum(loss_w, dim=[1, 2, 3])
loss_h = fluid.layers.abs(h - th) * tscale_tobj
loss_h = fluid.layers.reduce_sum(loss_h, dim=[1, 2, 3])
loss_obj_pos, loss_obj_neg = _calc_obj_loss(
output, obj, tobj, gt_box, batch_size, anchors, num_classes, downsample,
ignore_thresh, scale_x_y)
loss_cls = fluid.layers.sigmoid_cross_entropy_with_logits(cls, tcls)
loss_cls = fluid.layers.elementwise_mul(loss_cls, tobj, axis=0)
loss_cls = fluid.layers.reduce_sum(loss_cls, dim=[1, 2, 3, 4])
loss_xys = fluid.layers.reduce_mean(loss_x + loss_y)
loss_whs = fluid.layers.reduce_mean(loss_w + loss_h)
loss_objs = fluid.layers.reduce_mean(loss_obj_pos + loss_obj_neg)
loss_clss = fluid.layers.reduce_mean(loss_cls)
losses_all = {
"loss_xy": fluid.layers.sum(loss_xys),
"loss_wh": fluid.layers.sum(loss_whs),
"loss_loc": fluid.layers.sum(loss_xys) + fluid.layers.sum(loss_whs),
"loss_obj": fluid.layers.sum(loss_objs),
"loss_cls": fluid.layers.sum(loss_clss),
}
return losses_all, x, y, tx, ty
def gt2yolotarget(gt_bbox, gt_class, gt_score, anchors, mask, num_classes, size,
stride):
grid_h, grid_w = size
h, w = grid_h * stride, grid_w * stride
an_hw = np.array(anchors) / np.array([[w, h]])
target = np.zeros(
(len(mask), 6 + num_classes, grid_h, grid_w), dtype=np.float32)
for b in range(gt_bbox.shape[0]):
gx, gy, gw, gh = gt_bbox[b, :]
cls = gt_class[b]
score = gt_score[b]
if gw <= 0. or gh <= 0. or score <= 0.:
continue
# find best match anchor index
best_iou = 0.
best_idx = -1
for an_idx in range(an_hw.shape[0]):
iou = jaccard_overlap([0., 0., gw, gh],
[0., 0., an_hw[an_idx, 0], an_hw[an_idx, 1]])
if iou > best_iou:
best_iou = iou
best_idx = an_idx
gi = int(gx * grid_w)
gj = int(gy * grid_h)
# gtbox should be regresed in this layes if best match
# anchor index in anchor mask of this layer
if best_idx in mask:
best_n = mask.index(best_idx)
# x, y, w, h, scale
target[best_n, 0, gj, gi] = gx * grid_w - gi
target[best_n, 1, gj, gi] = gy * grid_h - gj
target[best_n, 2, gj, gi] = np.log(gw * w / anchors[best_idx][0])
target[best_n, 3, gj, gi] = np.log(gh * h / anchors[best_idx][1])
target[best_n, 4, gj, gi] = 2.0 - gw * gh
# objectness record gt_score
# if target[best_n, 5, gj, gi] > 0:
# print('find 1 duplicate')
target[best_n, 5, gj, gi] = score
# classification
target[best_n, 6 + cls, gj, gi] = 1.
return target
class TestYolov3LossOp(unittest.TestCase):
def setUp(self):
self.initTestCase()
x = np.random.uniform(0, 1, self.x_shape).astype('float64')
gtbox = np.random.random(size=self.gtbox_shape).astype('float64')
gtlabel = np.random.randint(0, self.class_num, self.gtbox_shape[:2])
gtmask = np.random.randint(0, 2, self.gtbox_shape[:2])
gtbox = gtbox * gtmask[:, :, np.newaxis]
gtlabel = gtlabel * gtmask
gtscore = np.ones(self.gtbox_shape[:2]).astype('float64')
if self.gtscore:
gtscore = np.random.random(self.gtbox_shape[:2]).astype('float64')
target = []
for box, label, score in zip(gtbox, gtlabel, gtscore):
target.append(
gt2yolotarget(box, label, score, self.anchors, self.anchor_mask,
self.class_num, (self.h, self.w
), self.downsample_ratio))
self.target = np.array(target).astype('float64')
self.mask_anchors = []
for i in self.anchor_mask:
self.mask_anchors.extend(self.anchors[i])
self.x = x
self.gtbox = gtbox
self.gtlabel = gtlabel
self.gtscore = gtscore
def initTestCase(self):
self.b = 8
self.h = 19
self.w = 19
self.anchors = [[10, 13], [16, 30], [33, 23], [30, 61], [62, 45],
[59, 119], [116, 90], [156, 198], [373, 326]]
self.anchor_mask = [6, 7, 8]
self.na = len(self.anchor_mask)
self.class_num = 80
self.ignore_thresh = 0.7
self.downsample_ratio = 32
self.x_shape = (self.b, len(self.anchor_mask) * (5 + self.class_num),
self.h, self.w)
self.gtbox_shape = (self.b, 40, 4)
self.gtscore = True
self.use_label_smooth = False
self.scale_x_y = 1.
def test_loss(self):
x, gtbox, gtlabel, gtscore, target = self.x, self.gtbox, self.gtlabel, self.gtscore, self.target
yolo_loss = YOLOv3Loss(
ignore_thresh=self.ignore_thresh,
label_smooth=self.use_label_smooth,
num_classes=self.class_num,
downsample=self.downsample_ratio,
scale_x_y=self.scale_x_y)
x = paddle.to_tensor(x.astype(np.float32))
gtbox = paddle.to_tensor(gtbox.astype(np.float32))
gtlabel = paddle.to_tensor(gtlabel.astype(np.float32))
gtscore = paddle.to_tensor(gtscore.astype(np.float32))
t = paddle.to_tensor(target.astype(np.float32))
anchor = [self.anchors[i] for i in self.anchor_mask]
(yolo_loss1, px, py, tx, ty) = fine_grained_loss(
output=x,
target=t,
gt_box=gtbox,
batch_size=self.b,
num_classes=self.class_num,
anchors=self.mask_anchors,
ignore_thresh=self.ignore_thresh,
downsample=self.downsample_ratio,
scale_x_y=self.scale_x_y)
yolo_loss2 = yolo_loss.yolov3_loss(
x, t, gtbox, anchor, self.downsample_ratio, self.scale_x_y)
for k in yolo_loss2:
self.assertAlmostEqual(
yolo_loss1[k].numpy()[0],
yolo_loss2[k].numpy()[0],
delta=1e-2,
msg=k)
class TestYolov3LossNoGTScore(TestYolov3LossOp):
def initTestCase(self):
self.b = 1
self.h = 76
self.w = 76
self.anchors = [[10, 13], [16, 30], [33, 23], [30, 61], [62, 45],
[59, 119], [116, 90], [156, 198], [373, 326]]
self.anchor_mask = [0, 1, 2]
self.na = len(self.anchor_mask)
self.class_num = 80
self.ignore_thresh = 0.7
self.downsample_ratio = 8
self.x_shape = (self.b, len(self.anchor_mask) * (5 + self.class_num),
self.h, self.w)
self.gtbox_shape = (self.b, 40, 4)
self.gtscore = False
self.use_label_smooth = False
self.scale_x_y = 1.
class TestYolov3LossWithScaleXY(TestYolov3LossOp):
def initTestCase(self):
self.b = 5
self.h = 38
self.w = 38
self.anchors = [[10, 13], [16, 30], [33, 23], [30, 61], [62, 45],
[59, 119], [116, 90], [156, 198], [373, 326]]
self.anchor_mask = [3, 4, 5]
self.na = len(self.anchor_mask)
self.class_num = 80
self.ignore_thresh = 0.7
self.downsample_ratio = 16
self.x_shape = (self.b, len(self.anchor_mask) * (5 + self.class_num),
self.h, self.w)
self.gtbox_shape = (self.b, 40, 4)
self.gtscore = True
self.use_label_smooth = False
self.scale_x_y = 1.2
if __name__ == "__main__":
unittest.main()