mindspore/example/ssd_coco2017/dataset.py

376 lines
14 KiB
Python

# Copyright 2020 Huawei Technologies Co., Ltd
#
# 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.
# ============================================================================
"""SSD dataset"""
from __future__ import division
import os
import math
import itertools as it
import numpy as np
import cv2
import mindspore.dataset as de
import mindspore.dataset.transforms.vision.c_transforms as C
from mindspore.mindrecord import FileWriter
from config import ConfigSSD
config = ConfigSSD()
class GeneratDefaultBoxes():
"""
Generate Default boxes for SSD, follows the order of (W, H, archor_sizes).
`self.default_boxes` has a shape of [archor_sizes, H, W, 4], the last dimension is [x, y, w, h].
`self.default_boxes_ltrb` has a shape as `self.default_boxes`, the last dimension is [x1, y1, x2, y2].
"""
def __init__(self):
fk = config.IMG_SHAPE[0] / np.array(config.STEPS)
self.default_boxes = []
for idex, feature_size in enumerate(config.FEATURE_SIZE):
sk1 = config.SCALES[idex] / config.IMG_SHAPE[0]
sk2 = config.SCALES[idex + 1] / config.IMG_SHAPE[0]
sk3 = math.sqrt(sk1 * sk2)
if config.NUM_DEFAULT[idex] == 3:
all_sizes = [(0.5, 1.0), (1.0, 1.0), (1.0, 0.5)]
else:
all_sizes = [(sk1, sk1), (sk3, sk3)]
for aspect_ratio in config.ASPECT_RATIOS[idex]:
w, h = sk1 * math.sqrt(aspect_ratio), sk1 / math.sqrt(aspect_ratio)
all_sizes.append((w, h))
all_sizes.append((h, w))
assert len(all_sizes) == config.NUM_DEFAULT[idex]
for i, j in it.product(range(feature_size), repeat=2):
for w, h in all_sizes:
cx, cy = (j + 0.5) / fk[idex], (i + 0.5) / fk[idex]
box = [np.clip(k, 0, 1) for k in (cx, cy, w, h)]
self.default_boxes.append(box)
def to_ltrb(cx, cy, w, h):
return cx - w / 2, cy - h / 2, cx + w / 2, cy + h / 2
# For IoU calculation
self.default_boxes_ltrb = np.array(tuple(to_ltrb(*i) for i in self.default_boxes), dtype='float32')
self.default_boxes = np.array(self.default_boxes, dtype='float32')
default_boxes_ltrb = GeneratDefaultBoxes().default_boxes_ltrb
default_boxes = GeneratDefaultBoxes().default_boxes
x1, y1, x2, y2 = np.split(default_boxes_ltrb[:, :4], 4, axis=-1)
vol_anchors = (x2 - x1) * (y2 - y1)
matching_threshold = config.MATCH_THRESHOLD
def ssd_bboxes_encode(boxes):
"""
Labels anchors with ground truth inputs.
Args:
boxex: ground truth with shape [N, 5], for each row, it stores [x, y, w, h, cls].
Returns:
gt_loc: location ground truth with shape [num_anchors, 4].
gt_label: class ground truth with shape [num_anchors, 1].
num_matched_boxes: number of positives in an image.
"""
def jaccard_with_anchors(bbox):
"""Compute jaccard score a box and the anchors."""
# Intersection bbox and volume.
xmin = np.maximum(x1, bbox[0])
ymin = np.maximum(y1, bbox[1])
xmax = np.minimum(x2, bbox[2])
ymax = np.minimum(y2, bbox[3])
w = np.maximum(xmax - xmin, 0.)
h = np.maximum(ymax - ymin, 0.)
# Volumes.
inter_vol = h * w
union_vol = vol_anchors + (bbox[2] - bbox[0]) * (bbox[3] - bbox[1]) - inter_vol
jaccard = inter_vol / union_vol
return np.squeeze(jaccard)
pre_scores = np.zeros((config.NUM_SSD_BOXES), dtype=np.float32)
t_boxes = np.zeros((config.NUM_SSD_BOXES, 4), dtype=np.float32)
t_label = np.zeros((config.NUM_SSD_BOXES), dtype=np.int64)
for bbox in boxes:
label = int(bbox[4])
scores = jaccard_with_anchors(bbox)
mask = (scores > matching_threshold)
if not np.any(mask):
mask[np.argmax(scores)] = True
mask = mask & (scores > pre_scores)
pre_scores = np.maximum(pre_scores, scores)
t_label = mask * label + (1 - mask) * t_label
for i in range(4):
t_boxes[:, i] = mask * bbox[i] + (1 - mask) * t_boxes[:, i]
index = np.nonzero(t_label)
# Transform to ltrb.
bboxes = np.zeros((config.NUM_SSD_BOXES, 4), dtype=np.float32)
bboxes[:, [0, 1]] = (t_boxes[:, [0, 1]] + t_boxes[:, [2, 3]]) / 2
bboxes[:, [2, 3]] = t_boxes[:, [2, 3]] - t_boxes[:, [0, 1]]
# Encode features.
bboxes_t = bboxes[index]
default_boxes_t = default_boxes[index]
bboxes_t[:, :2] = (bboxes_t[:, :2] - default_boxes_t[:, :2]) / (default_boxes_t[:, 2:] * config.PRIOR_SCALING[0])
bboxes_t[:, 2:4] = np.log(bboxes_t[:, 2:4] / default_boxes_t[:, 2:4]) / config.PRIOR_SCALING[1]
bboxes[index] = bboxes_t
num_match_num = np.array([len(np.nonzero(t_label)[0])], dtype=np.int32)
return bboxes, t_label.astype(np.int32), num_match_num
def ssd_bboxes_decode(boxes, index):
"""Decode predict boxes to [x, y, w, h]"""
boxes_t = boxes[index]
default_boxes_t = default_boxes[index]
boxes_t[:, :2] = boxes_t[:, :2] * config.PRIOR_SCALING[0] * default_boxes_t[:, 2:] + default_boxes_t[:, :2]
boxes_t[:, 2:4] = np.exp(boxes_t[:, 2:4] * config.PRIOR_SCALING[1]) * default_boxes_t[:, 2:4]
bboxes = np.zeros((len(boxes_t), 4), dtype=np.float32)
bboxes[:, [0, 1]] = boxes_t[:, [0, 1]] - boxes_t[:, [2, 3]] / 2
bboxes[:, [2, 3]] = boxes_t[:, [0, 1]] + boxes_t[:, [2, 3]] / 2
return bboxes
def preprocess_fn(image, box, is_training):
"""Preprocess function for dataset."""
def _rand(a=0., b=1.):
"""Generate random."""
return np.random.rand() * (b - a) + a
def _infer_data(image, input_shape, box):
img_h, img_w, _ = image.shape
input_h, input_w = input_shape
scale = min(float(input_w) / float(img_w), float(input_h) / float(img_h))
nw = int(img_w * scale)
nh = int(img_h * scale)
image = cv2.resize(image, (nw, nh))
new_image = np.zeros((input_h, input_w, 3), np.float32)
dh = (input_h - nh) // 2
dw = (input_w - nw) // 2
new_image[dh: (nh + dh), dw: (nw + dw), :] = image
image = new_image
#When the channels of image is 1
if len(image.shape) == 2:
image = np.expand_dims(image, axis=-1)
image = np.concatenate([image, image, image], axis=-1)
box = box.astype(np.float32)
box[:, [0, 2]] = (box[:, [0, 2]] * scale + dw) / input_w
box[:, [1, 3]] = (box[:, [1, 3]] * scale + dh) / input_h
return image, np.array((img_h, img_w), np.float32), box
def _data_aug(image, box, is_training, image_size=(300, 300)):
"""Data augmentation function."""
ih, iw, _ = image.shape
w, h = image_size
if not is_training:
return _infer_data(image, image_size, box)
# Random settings
scale_w = _rand(0.75, 1.25)
scale_h = _rand(0.75, 1.25)
flip = _rand() < .5
nw = iw * scale_w
nh = ih * scale_h
scale = min(w / nw, h / nh)
nw = int(scale * nw)
nh = int(scale * nh)
# Resize image
image = cv2.resize(image, (nw, nh))
# place image
new_image = np.zeros((h, w, 3), dtype=np.float32)
dw = (w - nw) // 2
dh = (h - nh) // 2
new_image[dh:dh + nh, dw:dw + nw, :] = image
image = new_image
# Flip image or not
if flip:
image = cv2.flip(image, 1, dst=None)
# Convert image to gray or not
gray = _rand() < .25
if gray:
image = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
# When the channels of image is 1
if len(image.shape) == 2:
image = np.expand_dims(image, axis=-1)
image = np.concatenate([image, image, image], axis=-1)
box = box.astype(np.float32)
# Transform box with shape[x1, y1, x2, y2].
box[:, [0, 2]] = (box[:, [0, 2]] * scale * scale_w + dw) / w
box[:, [1, 3]] = (box[:, [1, 3]] * scale * scale_h + dh) / h
if flip:
box[:, [0, 2]] = 1 - box[:, [2, 0]]
box, label, num_match_num = ssd_bboxes_encode(box)
return image, box, label, num_match_num
return _data_aug(image, box, is_training, image_size=config.IMG_SHAPE)
def create_coco_label(is_training):
"""Get image path and annotation from COCO."""
from pycocotools.coco import COCO
coco_root = config.COCO_ROOT
data_type = config.VAL_DATA_TYPE
if is_training:
data_type = config.TRAIN_DATA_TYPE
#Classes need to train or test.
train_cls = config.COCO_CLASSES
train_cls_dict = {}
for i, cls in enumerate(train_cls):
train_cls_dict[cls] = i
anno_json = os.path.join(coco_root, config.INSTANCES_SET.format(data_type))
coco = COCO(anno_json)
classs_dict = {}
cat_ids = coco.loadCats(coco.getCatIds())
for cat in cat_ids:
classs_dict[cat["id"]] = cat["name"]
image_ids = coco.getImgIds()
image_files = []
image_anno_dict = {}
for img_id in image_ids:
image_info = coco.loadImgs(img_id)
file_name = image_info[0]["file_name"]
anno_ids = coco.getAnnIds(imgIds=img_id, iscrowd=None)
anno = coco.loadAnns(anno_ids)
image_path = os.path.join(coco_root, data_type, file_name)
annos = []
for label in anno:
bbox = label["bbox"]
class_name = classs_dict[label["category_id"]]
if class_name in train_cls:
x_min, x_max = bbox[0], bbox[0] + bbox[2]
y_min, y_max = bbox[1], bbox[1] + bbox[3]
annos.append(list(map(round, [x_min, y_min, x_max, y_max])) + [train_cls_dict[class_name]])
if len(annos) >= 1:
image_files.append(image_path)
image_anno_dict[image_path] = np.array(annos)
return image_files, image_anno_dict
def anno_parser(annos_str):
"""Parse annotation from string to list."""
annos = []
for anno_str in annos_str:
anno = list(map(int, anno_str.strip().split(',')))
annos.append(anno)
return annos
def filter_valid_data(image_dir, anno_path):
"""Filter valid image file, which both in image_dir and anno_path."""
image_files = []
image_anno_dict = {}
if not os.path.isdir(image_dir):
raise RuntimeError("Path given is not valid.")
if not os.path.isfile(anno_path):
raise RuntimeError("Annotation file is not valid.")
with open(anno_path, "rb") as f:
lines = f.readlines()
for line in lines:
line_str = line.decode("utf-8").strip()
line_split = str(line_str).split(' ')
file_name = line_split[0]
image_path = os.path.join(image_dir, file_name)
if os.path.isfile(image_path):
image_anno_dict[image_path] = anno_parser(line_split[1:])
image_files.append(image_path)
return image_files, image_anno_dict
def data_to_mindrecord_byte_image(dataset="coco", is_training=True, prefix="ssd.mindrecord", file_num=8):
"""Create MindRecord file."""
mindrecord_dir = config.MINDRECORD_DIR
mindrecord_path = os.path.join(mindrecord_dir, prefix)
writer = FileWriter(mindrecord_path, file_num)
if dataset == "coco":
image_files, image_anno_dict = create_coco_label(is_training)
else:
image_files, image_anno_dict = filter_valid_data(config.IMAGE_DIR, config.ANNO_PATH)
ssd_json = {
"image": {"type": "bytes"},
"annotation": {"type": "int32", "shape": [-1, 5]},
}
writer.add_schema(ssd_json, "ssd_json")
for image_name in image_files:
with open(image_name, 'rb') as f:
img = f.read()
annos = np.array(image_anno_dict[image_name], dtype=np.int32)
row = {"image": img, "annotation": annos}
writer.write_raw_data([row])
writer.commit()
def create_ssd_dataset(mindrecord_file, batch_size=32, repeat_num=10, device_num=1, rank=0,
is_training=True, num_parallel_workers=4):
"""Creatr SSD dataset with MindDataset."""
ds = de.MindDataset(mindrecord_file, columns_list=["image", "annotation"], num_shards=device_num, shard_id=rank,
num_parallel_workers=num_parallel_workers, shuffle=is_training)
decode = C.Decode()
ds = ds.map(input_columns=["image"], operations=decode)
compose_map_func = (lambda image, annotation: preprocess_fn(image, annotation, is_training))
if is_training:
hwc_to_chw = C.HWC2CHW()
ds = ds.map(input_columns=["image", "annotation"],
output_columns=["image", "box", "label", "num_match_num"],
columns_order=["image", "box", "label", "num_match_num"],
operations=compose_map_func, python_multiprocessing=True, num_parallel_workers=num_parallel_workers)
ds = ds.map(input_columns=["image"], operations=hwc_to_chw, python_multiprocessing=True,
num_parallel_workers=num_parallel_workers)
ds = ds.batch(batch_size, drop_remainder=True)
ds = ds.repeat(repeat_num)
else:
hwc_to_chw = C.HWC2CHW()
ds = ds.map(input_columns=["image", "annotation"],
output_columns=["image", "image_shape", "annotation"],
columns_order=["image", "image_shape", "annotation"],
operations=compose_map_func)
ds = ds.map(input_columns=["image"], operations=hwc_to_chw, num_parallel_workers=num_parallel_workers)
ds = ds.batch(batch_size, drop_remainder=True)
ds = ds.repeat(repeat_num)
return ds