中文字幕av专区_日韩电影在线播放_精品国产精品久久一区免费式_av在线免费观看网站

溫馨提示×

溫馨提示×

您好,登錄后才能下訂單哦!

密碼登錄×
登錄注冊×
其他方式登錄
點擊 登錄注冊 即表示同意《億速云用戶服務條款》

pytorch制作自己的LMDB數據操作示例

發布時間:2020-09-20 18:06:31 來源:腳本之家 閱讀:183 作者:團長sama 欄目:開發技術

本文實例講述了pytorch制作自己的LMDB數據操作。分享給大家供大家參考,具體如下:

前言

記錄下pytorch里如何使用lmdb的code,自用

制作部分的Code

code就是ASTER里數據制作部分的代碼改了點,aster_train.txt里面就算圖片的完整路徑每行一個,圖片同目錄下有同名的txt,里面記著jpg的標簽

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)#最大空間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
  #數據庫中都是二進制數據
  imageKey = 'image-%09d' % cnt#9位數不足填零
  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)

讀取部分

這里用的pytorch的dataloader,簡單記錄一下,人比較懶,代碼就直接抄過來,不整理拆分了,重點看__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是一個分布式的框架 跳過
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需要一個類文件對象 所以這里需要把二進制轉為一個類文件對象
  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

更多關于Python相關內容可查看本站專題:《Python數學運算技巧總結》、《Python圖片操作技巧總結》、《Python數據結構與算法教程》、《Python函數使用技巧總結》、《Python字符串操作技巧匯總》及《Python入門與進階經典教程》

希望本文所述對大家Python程序設計有所幫助。

向AI問一下細節

免責聲明:本站發布的內容(圖片、視頻和文字)以原創、轉載和分享為主,文章觀點不代表本網站立場,如果涉及侵權請聯系站長郵箱:is@yisu.com進行舉報,并提供相關證據,一經查實,將立刻刪除涉嫌侵權內容。

AI

清涧县| 万源市| 上思县| 蒙山县| 凌云县| 淮滨县| 新建县| 崇明县| 繁昌县| 锦州市| 扎鲁特旗| 贵德县| 治县。| 肇州县| 西贡区| 云霄县| 和林格尔县| 武平县| 昭觉县| 石家庄市| 神农架林区| 包头市| 上饶市| 西林县| 嘉黎县| 哈巴河县| 翼城县| 杭锦后旗| 建平县| 太保市| 玛沁县| 凌云县| 新建县| 房山区| 南郑县| 湘潭县| 兴隆县| 万山特区| 桐乡市| 津南区| 潮安县|