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import os
import io
import cv2
import numpy as np
import torch
from torchvision import transforms
import warnings
from decord import VideoReader, cpu
from torch.utils.data import Dataset
from .random_erasing import RandomErasing
from .video_transforms import (
Compose, Resize, CenterCrop, Normalize,
create_random_augment, random_short_side_scale_jitter,
random_crop, random_resized_crop_with_shift, random_resized_crop,
horizontal_flip, random_short_side_scale_jitter, uniform_crop,
)
from .volume_transforms import ClipToTensor
try:
from petrel_client.client import Client
has_client = True
except ImportError:
has_client = False
class HMDBRawFrameClsDataset(Dataset):
"""Load your own raw frame classification dataset."""
def __init__(self, anno_path, prefix='', split=' ', mode='train', clip_len=8,
crop_size=224, short_side_size=256, new_height=256, new_width=340,
keep_aspect_ratio=True, num_segment=1, num_crop=1, test_num_segment=10,
test_num_crop=3, filename_tmpl='img_{:05}.jpg', args=None):
self.anno_path = anno_path
self.prefix = prefix
self.split = split
self.mode = mode
self.clip_len = clip_len
self.crop_size = crop_size
self.short_side_size = short_side_size
self.new_height = new_height
self.new_width = new_width
self.keep_aspect_ratio = keep_aspect_ratio
self.num_segment = num_segment
self.test_num_segment = test_num_segment
self.num_crop = num_crop
self.test_num_crop = test_num_crop
self.filename_tmpl = filename_tmpl
self.args = args
self.aug = False
self.rand_erase = False
self.client = None
if has_client:
self.client = Client('~/petreloss.conf')
if self.mode in ['train']:
self.aug = True
if self.args.reprob > 0:
self.rand_erase = True
if VideoReader is None:
raise ImportError(
"Unable to import `decord` which is required to read videos.")
import pandas as pd
cleaned = pd.read_csv(self.anno_path, header=None, delimiter=self.split)
self.dataset_samples = list(cleaned.values[:, 0].astype('str'))
self.total_frames = list(cleaned.values[:, 1] - 1) # max - 1
self.label_array = list(cleaned.values[:, -1])
if (mode == 'train'):
pass
elif (mode == 'validation'):
self.data_transform = Compose([
Resize(self.short_side_size,
interpolation='bilinear'),
CenterCrop(size=(self.crop_size,
self.crop_size)),
ClipToTensor(),
Normalize(mean=[0.485, 0.456, 0.406],
std=[0.229, 0.224, 0.225])
])
elif mode == 'test':
self.data_resize = Compose([
Resize(size=(short_side_size),
interpolation='bilinear')
])
self.data_transform = Compose([
ClipToTensor(),
Normalize(mean=[0.485, 0.456, 0.406],
std=[0.229, 0.224, 0.225])
])
self.test_seg = []
self.test_dataset = []
self.test_total_frames = []
self.test_label_array = []
for ck in range(self.test_num_segment):
for cp in range(self.test_num_crop):
for idx in range(len(self.label_array)):
self.test_seg.append((ck, cp))
self.test_dataset.append(self.dataset_samples[idx])
self.test_total_frames.append(self.total_frames[idx])
self.test_label_array.append(self.label_array[idx])
def __getitem__(self, index):
if self.mode == 'train':
args = self.args
scale_t = 1
sample = self.dataset_samples[index]
total_frame = self.total_frames[index]
buffer = self.load_frame(sample,
total_frame,
sample_rate_scale=scale_t) # T H W C
if len(buffer) == 0:
while len(buffer) == 0:
warnings.warn(
"video {} not correctly loaded during training".format(
sample))
index = np.random.randint(self.__len__())
sample = self.dataset_samples[index]
total_frame = self.total_frames[index]
buffer = self.load_frame(sample,
total_frame,
sample_rate_scale=scale_t)
if args.num_sample > 1:
frame_list = []
label_list = []
index_list = []
for _ in range(args.num_sample):
new_frames = self._aug_frame(buffer, args)
label = self.label_array[index]
frame_list.append(new_frames)
label_list.append(label)
index_list.append(index)
return frame_list, label_list, index_list, {}
else:
buffer = self._aug_frame(buffer, args)
return buffer, self.label_array[index], index, {}
elif self.mode == 'validation':
sample = self.dataset_samples[index]
total_frame = self.total_frames[index]
buffer = self.load_frame(sample, total_frame)
if len(buffer) == 0:
while len(buffer) == 0:
warnings.warn(
"video {} not correctly loaded during validation".
format(sample))
index = np.random.randint(self.__len__())
sample = self.dataset_samples[index]
buffer = self.load_frame(sample, total_frame)
buffer = self.data_transform(buffer)
return buffer, self.label_array[index], sample.split(
"/")[-1].split(".")[0]
elif self.mode == 'test':
sample = self.test_dataset[index]
total_frame = self.test_total_frames[index]
chunk_nb, split_nb = self.test_seg[index]
buffer = self.load_frame(sample, total_frame)
while len(buffer) == 0:
warnings.warn("video {}, temporal {}, spatial {} not found during testing".format(\
str(self.test_dataset[index]), chunk_nb, split_nb))
index = np.random.randint(self.__len__())
sample = self.test_dataset[index]
total_frame = self.test_total_frames[index]
chunk_nb, split_nb = self.test_seg[index]
buffer = self.load_frame(sample, total_frame)
buffer = self.data_resize(buffer)
if isinstance(buffer, list):
buffer = np.stack(buffer, 0)
if self.test_num_crop == 1:
spatial_start = int(1.0 * (max(buffer.shape[1], buffer.shape[2]) - self.short_side_size) / 2)
else:
spatial_step = 1.0 * (max(buffer.shape[1], buffer.shape[2]) - self.short_side_size) \
/ (self.test_num_crop - 1)
spatial_start = int(split_nb * spatial_step)
temporal_start = chunk_nb
if buffer.shape[1] >= buffer.shape[2]:
buffer = buffer[temporal_start::self.test_num_segment, \
spatial_start:spatial_start + self.short_side_size, :, :]
else:
buffer = buffer[temporal_start::self.test_num_segment, \
:, spatial_start:spatial_start + self.short_side_size, :]
buffer = self.data_transform(buffer)
return buffer, self.test_label_array[index], sample.split("/")[-1].split(".")[0], \
chunk_nb, split_nb
else:
raise NameError('mode {} unkown'.format(self.mode))
def _aug_frame(
self,
buffer,
args,
):
aug_transform = create_random_augment(
input_size=(self.crop_size, self.crop_size),
auto_augment=args.aa,
interpolation=args.train_interpolation,
)
buffer = [transforms.ToPILImage()(frame) for frame in buffer]
buffer = aug_transform(buffer)
buffer = [transforms.ToTensor()(img) for img in buffer]
buffer = torch.stack(buffer) # T C H W
buffer = buffer.permute(0, 2, 3, 1) # T H W C
# T H W C
buffer = tensor_normalize(buffer, [0.485, 0.456, 0.406],
[0.229, 0.224, 0.225])
# T H W C -> C T H W.
buffer = buffer.permute(3, 0, 1, 2)
# Perform data augmentation.
scl, asp = (
[0.08, 1.0],
[0.75, 1.3333],
)
buffer = spatial_sampling(
buffer,
spatial_idx=-1,
min_scale=256,
max_scale=320,
crop_size=self.crop_size,
random_horizontal_flip=False if args.data_set == 'SSV2' else True,
inverse_uniform_sampling=False,
aspect_ratio=asp,
scale=scl,
motion_shift=False)
if self.rand_erase:
erase_transform = RandomErasing(
args.reprob,
mode=args.remode,
max_count=args.recount,
num_splits=args.recount,
device="cpu",
)
buffer = buffer.permute(1, 0, 2, 3)
buffer = erase_transform(buffer)
buffer = buffer.permute(1, 0, 2, 3)
return buffer
def load_frame(self, sample, num_frames, sample_rate_scale=1):
"""Load video content using Decord"""
fname = sample
fname = os.path.join(self.prefix, fname)
if self.mode == 'test':
tick = num_frames / float(self.num_segment)
all_index = []
for t_seg in range(self.test_num_segment):
tmp_index = [
int(t_seg * tick / self.test_num_segment + tick * x)
for x in range(self.num_segment)
]
all_index.extend(tmp_index)
all_index = list(np.sort(np.array(all_index)))
imgs = []
for idx in all_index:
frame_fname = os.path.join(fname, self.filename_tmpl.format(idx + 1))
if "s3://" in fname:
img_bytes = self.client.get(frame_fname)
else:
with open(frame_fname, 'rb') as f:
img_bytes = f.read()
img_np = np.frombuffer(img_bytes, np.uint8)
img = cv2.imdecode(img_np, cv2.IMREAD_COLOR)
cv2.cvtColor(img, cv2.COLOR_BGR2RGB, img)
imgs.append(img)
buffer = np.array(imgs)
return buffer
# handle temporal segments
average_duration = num_frames // self.num_segment
all_index = []
if average_duration > 0:
if self.mode == 'validation':
all_index = list(
np.multiply(list(range(self.num_segment)),
average_duration) +
np.ones(self.num_segment, dtype=int) *
(average_duration // 2))
else:
all_index = list(
np.multiply(list(range(self.num_segment)),
average_duration) +
np.random.randint(average_duration, size=self.num_segment))
elif num_frames > self.num_segment:
if self.mode == 'validation':
all_index = list(range(self.num_segment))
else:
all_index = list(
np.sort(
np.random.randint(num_frames, size=self.num_segment)))
else:
all_index = [0] * (self.num_segment - num_frames) + list(
range(num_frames))
all_index = list(np.array(all_index))
imgs = []
for idx in all_index:
frame_fname = os.path.join(fname, self.filename_tmpl.format(idx + 1))
if "s3://" in fname:
img_bytes = self.client.get(frame_fname)
else:
with open(frame_fname, 'rb') as f:
img_bytes = f.read()
try:
img_np = np.frombuffer(img_bytes, np.uint8)
except Exception:
print(f"Error when reading {frame_fname}", flush=True)
return []
img = cv2.imdecode(img_np, cv2.IMREAD_COLOR)
cv2.cvtColor(img, cv2.COLOR_BGR2RGB, img)
imgs.append(img)
buffer = np.array(imgs)
return buffer
def __len__(self):
if self.mode != 'test':
return len(self.dataset_samples)
else:
return len(self.test_dataset)
class HMDBVideoClsDataset(Dataset):
"""Load your own video classification dataset."""
def __init__(self, anno_path, prefix='', split=' ', mode='train', clip_len=8,
crop_size=224, short_side_size=256, new_height=256,
new_width=340, keep_aspect_ratio=True, num_segment=1,
num_crop=1, test_num_segment=10, test_num_crop=3, filename_tmpl=None, args=None):
self.anno_path = anno_path
self.prefix = prefix
self.split = split
self.mode = mode
self.clip_len = clip_len
self.crop_size = crop_size
self.short_side_size = short_side_size
self.new_height = new_height
self.new_width = new_width
self.keep_aspect_ratio = keep_aspect_ratio
self.num_segment = num_segment
self.test_num_segment = test_num_segment
self.num_crop = num_crop
self.test_num_crop = test_num_crop
self.args = args
self.aug = False
self.rand_erase = False
self.client = None
if has_client:
self.client = Client('~/petreloss.conf')
if self.mode in ['train']:
self.aug = True
if self.args.reprob > 0:
self.rand_erase = True
if VideoReader is None:
raise ImportError("Unable to import `decord` which is required to read videos.")
import pandas as pd
cleaned = pd.read_csv(self.anno_path, header=None, delimiter=self.split)
self.dataset_samples = list(cleaned.values[:, 0])
self.label_array = list(cleaned.values[:, 1])
if (mode == 'train'):
pass
elif (mode == 'validation'):
self.data_transform = Compose([
Resize(self.short_side_size, interpolation='bilinear'),
CenterCrop(size=(self.crop_size, self.crop_size)),
ClipToTensor(),
Normalize(mean=[0.485, 0.456, 0.406],
std=[0.229, 0.224, 0.225])
])
elif mode == 'test':
self.data_resize = Compose([
Resize(size=(short_side_size), interpolation='bilinear')
])
self.data_transform = Compose([
ClipToTensor(),
Normalize(mean=[0.485, 0.456, 0.406],
std=[0.229, 0.224, 0.225])
])
self.test_seg = []
self.test_dataset = []
self.test_label_array = []
for ck in range(self.test_num_segment):
for cp in range(self.test_num_crop):
for idx in range(len(self.label_array)):
sample_label = self.label_array[idx]
self.test_label_array.append(sample_label)
self.test_dataset.append(self.dataset_samples[idx])
self.test_seg.append((ck, cp))
def __getitem__(self, index):
if self.mode == 'train':
args = self.args
scale_t = 1
sample = self.dataset_samples[index]
buffer = self.loadvideo_decord(sample, sample_rate_scale=scale_t) # T H W C
if len(buffer) == 0:
while len(buffer) == 0:
warnings.warn("video {} not correctly loaded during training".format(sample))
index = np.random.randint(self.__len__())
sample = self.dataset_samples[index]
buffer = self.loadvideo_decord(sample, sample_rate_scale=scale_t)
if args.num_sample > 1:
frame_list = []
label_list = []
index_list = []
for _ in range(args.num_sample):
new_frames = self._aug_frame(buffer, args)
label = self.label_array[index]
frame_list.append(new_frames)
label_list.append(label)
index_list.append(index)
return frame_list, label_list, index_list, {}
else:
buffer = self._aug_frame(buffer, args)
return buffer, self.label_array[index], index, {}
elif self.mode == 'validation':
sample = self.dataset_samples[index]
buffer = self.loadvideo_decord(sample)
if len(buffer) == 0:
while len(buffer) == 0:
warnings.warn("video {} not correctly loaded during validation".format(sample))
index = np.random.randint(self.__len__())
sample = self.dataset_samples[index]
buffer = self.loadvideo_decord(sample)
buffer = self.data_transform(buffer)
return buffer, self.label_array[index], sample.split("/")[-1].split(".")[0]
elif self.mode == 'test':
sample = self.test_dataset[index]
chunk_nb, split_nb = self.test_seg[index]
buffer = self.loadvideo_decord(sample)
while len(buffer) == 0:
warnings.warn("video {}, temporal {}, spatial {} not found during testing".format(\
str(self.test_dataset[index]), chunk_nb, split_nb))
index = np.random.randint(self.__len__())
sample = self.test_dataset[index]
chunk_nb, split_nb = self.test_seg[index]
buffer = self.loadvideo_decord(sample)
buffer = self.data_resize(buffer)
if isinstance(buffer, list):
buffer = np.stack(buffer, 0)
spatial_step = 1.0 * (max(buffer.shape[1], buffer.shape[2]) - self.short_side_size) \
/ (self.test_num_crop - 1)
temporal_start = chunk_nb # 0/1
spatial_start = int(split_nb * spatial_step)
if buffer.shape[1] >= buffer.shape[2]:
buffer = buffer[temporal_start::2, \
spatial_start:spatial_start + self.short_side_size, :, :]
else:
buffer = buffer[temporal_start::2, \
:, spatial_start:spatial_start + self.short_side_size, :]
buffer = self.data_transform(buffer)
return buffer, self.test_label_array[index], sample.split("/")[-1].split(".")[0], \
chunk_nb, split_nb
else:
raise NameError('mode {} unkown'.format(self.mode))
def _aug_frame(
self,
buffer,
args,
):
aug_transform = create_random_augment(
input_size=(self.crop_size, self.crop_size),
auto_augment=args.aa,
interpolation=args.train_interpolation,
)
buffer = [
transforms.ToPILImage()(frame) for frame in buffer
]
buffer = aug_transform(buffer)
buffer = [transforms.ToTensor()(img) for img in buffer]
buffer = torch.stack(buffer) # T C H W
buffer = buffer.permute(0, 2, 3, 1) # T H W C
# T H W C
buffer = tensor_normalize(
buffer, [0.485, 0.456, 0.406], [0.229, 0.224, 0.225]
)
# T H W C -> C T H W.
buffer = buffer.permute(3, 0, 1, 2)
# Perform data augmentation.
scl, asp = (
[0.08, 1.0],
[0.75, 1.3333],
)
buffer = spatial_sampling(
buffer,
spatial_idx=-1,
min_scale=256,
max_scale=320,
crop_size=self.crop_size,
random_horizontal_flip=False if args.data_set == 'SSV2' else True,
inverse_uniform_sampling=False,
aspect_ratio=asp,
scale=scl,
motion_shift=False
)
if self.rand_erase:
erase_transform = RandomErasing(
args.reprob,
mode=args.remode,
max_count=args.recount,
num_splits=args.recount,
device="cpu",
)
buffer = buffer.permute(1, 0, 2, 3)
buffer = erase_transform(buffer)
buffer = buffer.permute(1, 0, 2, 3)
return buffer
def loadvideo_decord(self, sample, sample_rate_scale=1):
"""Load video content using Decord"""
fname = sample
fname = os.path.join(self.prefix, fname)
try:
if self.keep_aspect_ratio:
if "s3://" in fname:
video_bytes = self.client.get(fname)
vr = VideoReader(io.BytesIO(video_bytes),
num_threads=1,
ctx=cpu(0))
else:
vr = VideoReader(fname, num_threads=1, ctx=cpu(0))
else:
if "s3://" in fname:
video_bytes = self.client.get(fname)
vr = VideoReader(io.BytesIO(video_bytes),
width=self.new_width,
height=self.new_height,
num_threads=1,
ctx=cpu(0))
else:
vr = VideoReader(fname, width=self.new_width, height=self.new_height,
num_threads=1, ctx=cpu(0))
except:
print("video cannot be loaded by decord: ", fname)
return []
if self.mode == 'test':
tick = len(vr) / float(self.num_segment)
all_index = list(np.array([int(tick / 2.0 + tick * x) for x in range(self.num_segment)] +
[int(tick * x) for x in range(self.num_segment)]))
while len(all_index) < (self.num_segment * self.test_num_segment):
all_index.append(all_index[-1])
all_index = np.sort(np.array(all_index))
vr.seek(0)
buffer = vr.get_batch(all_index).asnumpy()
return buffer
elif self.mode == 'validation':
tick = len(vr) / float(self.num_segment)
all_index = np.array([int(tick / 2.0 + tick * x) for x in range(self.num_segment)])
vr.seek(0)
buffer = vr.get_batch(all_index).asnumpy()
return buffer
# handle temporal segments
average_duration = len(vr) // self.num_segment
if average_duration > 0:
all_index = list(np.multiply(list(range(self.num_segment)), average_duration) + np.random.randint(average_duration,
size=self.num_segment))
elif len(vr) > self.num_segment:
all_index = list(np.sort(np.random.randint(len(vr), size=self.num_segment)))
else:
all_index = list(np.zeros((self.num_segment,)))
vr.seek(0)
buffer = vr.get_batch(all_index).asnumpy()
return buffer
def __len__(self):
if self.mode != 'test':
return len(self.dataset_samples)
else:
return len(self.test_dataset)
def spatial_sampling(
frames,
spatial_idx=-1,
min_scale=256,
max_scale=320,
crop_size=224,
random_horizontal_flip=True,
inverse_uniform_sampling=False,
aspect_ratio=None,
scale=None,
motion_shift=False,
):
"""
Perform spatial sampling on the given video frames. If spatial_idx is
-1, perform random scale, random crop, and random flip on the given
frames. If spatial_idx is 0, 1, or 2, perform spatial uniform sampling
with the given spatial_idx.
Args:
frames (tensor): frames of images sampled from the video. The
dimension is `num frames` x `height` x `width` x `channel`.
spatial_idx (int): if -1, perform random spatial sampling. If 0, 1,
or 2, perform left, center, right crop if width is larger than
height, and perform top, center, buttom crop if height is larger
than width.
min_scale (int): the minimal size of scaling.
max_scale (int): the maximal size of scaling.
crop_size (int): the size of height and width used to crop the
frames.
inverse_uniform_sampling (bool): if True, sample uniformly in
[1 / max_scale, 1 / min_scale] and take a reciprocal to get the
scale. If False, take a uniform sample from [min_scale,
max_scale].
aspect_ratio (list): Aspect ratio range for resizing.
scale (list): Scale range for resizing.
motion_shift (bool): Whether to apply motion shift for resizing.
Returns:
frames (tensor): spatially sampled frames.
"""
assert spatial_idx in [-1, 0, 1, 2]
if spatial_idx == -1:
if aspect_ratio is None and scale is None:
frames, _ = random_short_side_scale_jitter(
images=frames,
min_size=min_scale,
max_size=max_scale,
inverse_uniform_sampling=inverse_uniform_sampling,
)
frames, _ = random_crop(frames, crop_size)
else:
transform_func = (
random_resized_crop_with_shift
if motion_shift
else random_resized_crop
)
frames = transform_func(
images=frames,
target_height=crop_size,
target_width=crop_size,
scale=scale,
ratio=aspect_ratio,
)
if random_horizontal_flip:
frames, _ = horizontal_flip(0.5, frames)
else:
# The testing is deterministic and no jitter should be performed.
# min_scale, max_scale, and crop_size are expect to be the same.
assert len({min_scale, max_scale, crop_size}) == 1
frames, _ = random_short_side_scale_jitter(
frames, min_scale, max_scale
)
frames, _ = uniform_crop(frames, crop_size, spatial_idx)
return frames
def tensor_normalize(tensor, mean, std):
"""
Normalize a given tensor by subtracting the mean and dividing the std.
Args:
tensor (tensor): tensor to normalize.
mean (tensor or list): mean value to subtract.
std (tensor or list): std to divide.
"""
if tensor.dtype == torch.uint8:
tensor = tensor.float()
tensor = tensor / 255.0
if type(mean) == list:
mean = torch.tensor(mean)
if type(std) == list:
std = torch.tensor(std)
tensor = tensor - mean
tensor = tensor / std
return tensor
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