相思资源网 Design By www.200059.com

本文实例讲述了pytorch制作自己的LMDB数据操作。分享给大家供大家参考,具体如下:

前言

记录下pytorch里如何使用lmdb的code,自用

制作部分的Code

code就是ASTER里数据制作部分的代码改了点,aster_train.txt里面就算图片的完整路径每行一个,图片同目录下有同名的txt,里面记着jpg的标签

import os
import lmdb # install lmdb by "pip install lmdb"
import cv2
import numpy as np
from tqdm import tqdm
import six
from PIL import Image
import scipy.io as sio
from tqdm import tqdm
import re
def checkImageIsValid(imageBin):
 if imageBin is None:
  return False
 imageBuf = np.fromstring(imageBin, dtype=np.uint8)
 img = cv2.imdecode(imageBuf, cv2.IMREAD_GRAYSCALE)
 imgH, imgW = img.shape[0], img.shape[1]
 if imgH * imgW == 0:
  return False
 return True
def writeCache(env, cache):
 with env.begin(write=True) as txn:
  for k, v in cache.items():
   txn.put(k.encode(), v)
def _is_difficult(word):
 assert isinstance(word, str)
 return not re.match('^[\w]+$', word)
def createDataset(outputPath, imagePathList, labelList, lexiconList=None, checkValid=True):
 """
 Create LMDB dataset for CRNN training.
 ARGS:
   outputPath  : LMDB output path
   imagePathList : list of image path
   labelList   : list of corresponding groundtruth texts
   lexiconList  : (optional) list of lexicon lists
   checkValid  : if true, check the validity of every image
 """
 assert(len(imagePathList) == len(labelList))
 nSamples = len(imagePathList)
 env = lmdb.open(outputPath, map_size=1099511627776)#最大空间1048576GB
 cache = {}
 cnt = 1
 for i in range(nSamples):
  imagePath = imagePathList[i]
  label = labelList[i]
  if len(label) == 0:
   continue
  if not os.path.exists(imagePath):
   print('%s does not exist' % imagePath)
   continue
  with open(imagePath, 'rb') as f:
   imageBin = f.read()
  if checkValid:
   if not checkImageIsValid(imageBin):
    print('%s is not a valid image' % imagePath)
    continue
  #数据库中都是二进制数据
  imageKey = 'image-%09d' % cnt#9位数不足填零
  labelKey = 'label-%09d' % cnt
  cache[imageKey] = imageBin
  cache[labelKey] = label.encode()
  if lexiconList:
   lexiconKey = 'lexicon-%09d' % cnt
   cache[lexiconKey] = ' '.join(lexiconList[i])
  if cnt % 1000 == 0:
   writeCache(env, cache)
   cache = {}
   print('Written %d / %d' % (cnt, nSamples))
  cnt += 1
 nSamples = cnt-1
 cache['num-samples'] = str(nSamples).encode()
 writeCache(env, cache)
 print('Created dataset with %d samples' % nSamples)
def get_sample_list(txt_path:str):
  with open(txt_path,'r') as fr:
    jpg_list=[x.strip() for x in fr.readlines() if os.path.exists(x.replace('.jpg','.txt').strip())]
  txt_content_list=[]
  for jpg in jpg_list:
    label_path=jpg.replace('.jpg','.txt')
    with open(label_path,'r') as fr:
      try:
        str_tmp=fr.readline()
      except UnicodeDecodeError as e:
        print(label_path)
        raise(e)
      txt_content_list.append(str_tmp.strip())
  return jpg_list,txt_content_list
if __name__ == "__main__":
 txt_path='/home/gpu-server/disk/disk1/NumberData/8NumberSample/aster_train.txt'
 lmdb_output_path = '/home/gpu-server/project/aster/dataset/train'
 imagePathList,labelList=get_sample_list(txt_path)
 createDataset(lmdb_output_path, imagePathList, labelList)

读取部分

这里用的pytorch的dataloader,简单记录一下,人比较懒,代码就直接抄过来,不整理拆分了,重点看__getitem__

from __future__ import absolute_import
# import sys
# sys.path.append('./')
import os
# import moxing as mox
import pickle
from tqdm import tqdm
from PIL import Image, ImageFile
import numpy as np
import random
import cv2
import lmdb
import sys
import six
import torch
from torch.utils import data
from torch.utils.data import sampler
from torchvision import transforms
from lib.utils.labelmaps import get_vocabulary, labels2strs
from lib.utils import to_numpy
ImageFile.LOAD_TRUNCATED_IMAGES = True
from config import get_args
global_args = get_args(sys.argv[1:])
if global_args.run_on_remote:
 import moxing as mox
 #moxing是一个分布式的框架 跳过
class LmdbDataset(data.Dataset):
 def __init__(self, root, voc_type, max_len, num_samples, transform=None):
  super(LmdbDataset, self).__init__()
  if global_args.run_on_remote:
   dataset_name = os.path.basename(root)
   data_cache_url = "/cache/%s" % dataset_name
   if not os.path.exists(data_cache_url):
    os.makedirs(data_cache_url)
   if mox.file.exists(root):
    mox.file.copy_parallel(root, data_cache_url)
   else:
    raise ValueError("%s not exists!" % root)
   self.env = lmdb.open(data_cache_url, max_readers=32, readonly=True)
  else:
   self.env = lmdb.open(root, max_readers=32, readonly=True)
  assert self.env is not None, "cannot create lmdb from %s" % root
  self.txn = self.env.begin()
  self.voc_type = voc_type
  self.transform = transform
  self.max_len = max_len
  self.nSamples = int(self.txn.get(b"num-samples"))
  self.nSamples = min(self.nSamples, num_samples)
  assert voc_type in ['LOWERCASE', 'ALLCASES', 'ALLCASES_SYMBOLS','DIGITS']
  self.EOS = 'EOS'
  self.PADDING = 'PADDING'
  self.UNKNOWN = 'UNKNOWN'
  self.voc = get_vocabulary(voc_type, EOS=self.EOS, PADDING=self.PADDING, UNKNOWN=self.UNKNOWN)
  self.char2id = dict(zip(self.voc, range(len(self.voc))))
  self.id2char = dict(zip(range(len(self.voc)), self.voc))
  self.rec_num_classes = len(self.voc)
  self.lowercase = (voc_type == 'LOWERCASE')
 def __len__(self):
  return self.nSamples
 def __getitem__(self, index):
  assert index <= len(self), 'index range error'
  index += 1
  img_key = b'image-%09d' % index
  imgbuf = self.txn.get(img_key)
  #由于Image.open需要一个类文件对象 所以这里需要把二进制转为一个类文件对象
  buf = six.BytesIO()
  buf.write(imgbuf)
  buf.seek(0)
  try:
   img = Image.open(buf).convert('RGB')
   # img = Image.open(buf).convert('L')
   # img = img.convert('RGB')
  except IOError:
   print('Corrupted image for %d' % index)
   return self[index + 1]
  # reconition labels
  label_key = b'label-%09d' % index
  word = self.txn.get(label_key).decode()
  if self.lowercase:
   word = word.lower()
  ## fill with the padding token
  label = np.full((self.max_len,), self.char2id[self.PADDING], dtype=np.int)
  label_list = []
  for char in word:
   if char in self.char2id:
    label_list.append(self.char2id[char])
   else:
    ## add the unknown token
    print('{0} is out of vocabulary.'.format(char))
    label_list.append(self.char2id[self.UNKNOWN])
  ## add a stop token
  label_list = label_list + [self.char2id[self.EOS]]
  assert len(label_list) <= self.max_len
  label[:len(label_list)] = np.array(label_list)
  if len(label) <= 0:
   return self[index + 1]
  # label length
  label_len = len(label_list)
  if self.transform is not None:
   img = self.transform(img)
  return img, label, label_len

更多关于Python相关内容可查看本站专题:《Python数学运算技巧总结》、《Python图片操作技巧总结》、《Python数据结构与算法教程》、《Python函数使用技巧总结》、《Python字符串操作技巧汇总》及《Python入门与进阶经典教程》

希望本文所述对大家Python程序设计有所帮助。

标签:
pytorch,LMDB,数据操作

相思资源网 Design By www.200059.com
广告合作:本站广告合作请联系QQ:858582 申请时备注:广告合作(否则不回)
免责声明:本站文章均来自网站采集或用户投稿,网站不提供任何软件下载或自行开发的软件! 如有用户或公司发现本站内容信息存在侵权行为,请邮件告知! 858582#qq.com
相思资源网 Design By www.200059.com

评论“pytorch制作自己的LMDB数据操作示例”

暂无pytorch制作自己的LMDB数据操作示例的评论...

《魔兽世界》大逃杀!60人新游玩模式《强袭风暴》3月21日上线

暴雪近日发布了《魔兽世界》10.2.6 更新内容,新游玩模式《强袭风暴》即将于3月21 日在亚服上线,届时玩家将前往阿拉希高地展开一场 60 人大逃杀对战。

艾泽拉斯的冒险者已经征服了艾泽拉斯的大地及遥远的彼岸。他们在对抗世界上最致命的敌人时展现出过人的手腕,并且成功阻止终结宇宙等级的威胁。当他们在为即将于《魔兽世界》资料片《地心之战》中来袭的萨拉塔斯势力做战斗准备时,他们还需要在熟悉的阿拉希高地面对一个全新的敌人──那就是彼此。在《巨龙崛起》10.2.6 更新的《强袭风暴》中,玩家将会进入一个全新的海盗主题大逃杀式限时活动,其中包含极高的风险和史诗级的奖励。

《强袭风暴》不是普通的战场,作为一个独立于主游戏之外的活动,玩家可以用大逃杀的风格来体验《魔兽世界》,不分职业、不分装备(除了你在赛局中捡到的),光是技巧和战略的强弱之分就能决定出谁才是能坚持到最后的赢家。本次活动将会开放单人和双人模式,玩家在加入海盗主题的预赛大厅区域前,可以从强袭风暴角色画面新增好友。游玩游戏将可以累计名望轨迹,《巨龙崛起》和《魔兽世界:巫妖王之怒 经典版》的玩家都可以获得奖励。