PaddleOCR/ppocr/data/lmdb_dataset.py

116 lines
4.3 KiB
Python

# copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
#
# 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.
import numpy as np
import os
from paddle.io import Dataset
import lmdb
import cv2
from .imaug import transform, create_operators
class LMDBDataSet(Dataset):
def __init__(self, config, mode, logger, seed=None):
super(LMDBDataSet, self).__init__()
global_config = config['Global']
dataset_config = config[mode]['dataset']
loader_config = config[mode]['loader']
batch_size = loader_config['batch_size_per_card']
data_dir = dataset_config['data_dir']
self.do_shuffle = loader_config['shuffle']
self.lmdb_sets = self.load_hierarchical_lmdb_dataset(data_dir)
logger.info("Initialize indexs of datasets:%s" % data_dir)
self.data_idx_order_list = self.dataset_traversal()
if self.do_shuffle:
np.random.shuffle(self.data_idx_order_list)
self.ops = create_operators(dataset_config['transforms'], global_config)
def load_hierarchical_lmdb_dataset(self, data_dir):
lmdb_sets = {}
dataset_idx = 0
for dirpath, dirnames, filenames in os.walk(data_dir + '/'):
if not dirnames:
env = lmdb.open(
dirpath,
max_readers=32,
readonly=True,
lock=False,
readahead=False,
meminit=False)
txn = env.begin(write=False)
num_samples = int(txn.get('num-samples'.encode()))
lmdb_sets[dataset_idx] = {"dirpath":dirpath, "env":env, \
"txn":txn, "num_samples":num_samples}
dataset_idx += 1
return lmdb_sets
def dataset_traversal(self):
lmdb_num = len(self.lmdb_sets)
total_sample_num = 0
for lno in range(lmdb_num):
total_sample_num += self.lmdb_sets[lno]['num_samples']
data_idx_order_list = np.zeros((total_sample_num, 2))
beg_idx = 0
for lno in range(lmdb_num):
tmp_sample_num = self.lmdb_sets[lno]['num_samples']
end_idx = beg_idx + tmp_sample_num
data_idx_order_list[beg_idx:end_idx, 0] = lno
data_idx_order_list[beg_idx:end_idx, 1] \
= list(range(tmp_sample_num))
data_idx_order_list[beg_idx:end_idx, 1] += 1
beg_idx = beg_idx + tmp_sample_num
return data_idx_order_list
def get_img_data(self, value):
"""get_img_data"""
if not value:
return None
imgdata = np.frombuffer(value, dtype='uint8')
if imgdata is None:
return None
imgori = cv2.imdecode(imgdata, 1)
if imgori is None:
return None
return imgori
def get_lmdb_sample_info(self, txn, index):
label_key = 'label-%09d'.encode() % index
label = txn.get(label_key)
if label is None:
return None
label = label.decode('utf-8')
img_key = 'image-%09d'.encode() % index
imgbuf = txn.get(img_key)
return imgbuf, label
def __getitem__(self, idx):
lmdb_idx, file_idx = self.data_idx_order_list[idx]
lmdb_idx = int(lmdb_idx)
file_idx = int(file_idx)
sample_info = self.get_lmdb_sample_info(self.lmdb_sets[lmdb_idx]['txn'],
file_idx)
if sample_info is None:
return self.__getitem__(np.random.randint(self.__len__()))
img, label = sample_info
data = {'image': img, 'label': label}
outs = transform(data, self.ops)
if outs is None:
return self.__getitem__(np.random.randint(self.__len__()))
return outs
def __len__(self):
return self.data_idx_order_list.shape[0]