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Python怎么操作目標(biāo)檢測(cè)數(shù)據(jù)集xml?常用操作介紹!

猿友 2021-07-21 14:19:58 瀏覽數(shù) (2275)
反饋

在學(xué)習(xí)數(shù)據(jù)挖掘的時(shí)候小編發(fā)現(xiàn)有些數(shù)據(jù)集是使用xml文件來(lái)進(jìn)行數(shù)據(jù)管理的,而要對(duì)這樣的數(shù)據(jù)集進(jìn)行處理需要使用到python的XML支持,接下來(lái)的這篇文章我們就介紹一下這三個(gè)處理XML需要的知識(shí)點(diǎn):python統(tǒng)計(jì)xml標(biāo)簽數(shù)量;python修改xml標(biāo)簽內(nèi)容;python獲取xml數(shù)據(jù)。

1. 根據(jù)xml文件統(tǒng)計(jì)目標(biāo)種類以及數(shù)量

# -*- coding:utf-8 -*-
#根據(jù)xml文件統(tǒng)計(jì)目標(biāo)種類以及數(shù)量
import os
import xml.etree.ElementTree as ET
import numpy as np
np.set_printoptions(suppress=True, threshold=np.nan)
import matplotlib
from PIL import Image
 
def parse_obj(xml_path, filename):
  tree=ET.parse(xml_path+filename)
  objects=[]
  for obj in tree.findall('object'):
    obj_struct={}
    obj_struct['name']=obj.find('name').text
    objects.append(obj_struct)
  return objects
  
def read_image(image_path, filename):
  im=Image.open(image_path+filename)
  W=im.size[0]
  H=im.size[1]
  area=W*H
  im_info=[W,H,area]
  return im_info
  
if __name__ == '__main__':
  xml_path='/home/dlut/網(wǎng)絡(luò)/make_database/數(shù)據(jù)集——合集/VOCdevkit/VOC2018/Annotations/'
  filenamess=os.listdir(xml_path)
  filenames=[]
  for name in filenamess:
    name=name.replace('.xml','')
    filenames.append(name)
  recs={}
  obs_shape={}
  classnames=[]
  num_objs={}
  obj_avg={}
  for i,name in enumerate(filenames):
    recs[name]=parse_obj(xml_path, name+ '.xml' )
  for name in filenames:
    for object in recs[name]:
      if object['name'] not in num_objs.keys():
         num_objs[object['name']]=1
      else:
         num_objs[object['name']]+=1
      if object['name'] not in classnames:
         classnames.append(object['name'])
  for name in classnames:
    print('{}:{}個(gè)'.format(name,num_objs[name]))
  print('信息統(tǒng)計(jì)算完畢。')

運(yùn)行結(jié)果

2.根據(jù)xml文件統(tǒng)計(jì)目標(biāo)的平均長(zhǎng)度、寬度、面積以及每一個(gè)目標(biāo)在原圖中的占比

# -*- coding:utf-8 -*-
#統(tǒng)計(jì)
# 計(jì)算每一個(gè)目標(biāo)在原圖中的占比
# 計(jì)算目標(biāo)的平均長(zhǎng)度、
# 計(jì)算平均寬度,
# 計(jì)算平均面積、
# 計(jì)算目標(biāo)平均占比
import os
import xml.etree.ElementTree as ET
import numpy as np
#np.set_printoptions(suppress=True, threshold=np.nan)  #10,000,000
np.set_printoptions(suppress=True, threshold=10000000)  #10,000,000
import matplotlib
from PIL import Image
def parse_obj(xml_path, filename):
    tree = ET.parse(xml_path + filename)
    objects = []
    for obj in tree.findall('object'):
        obj_struct = {}
        obj_struct['name'] = obj.find('name').text
        bbox = obj.find('bndbox')
        obj_struct['bbox'] = [int(bbox.find('xmin').text),
                              int(bbox.find('ymin').text),
                              int(bbox.find('xmax').text),
                              int(bbox.find('ymax').text)]
        objects.append(obj_struct)
    return objects
def read_image(image_path, filename):
    im = Image.open(image_path + filename)
    W = im.size[0]
    H = im.size[1]
    area = W * H
    im_info = [W, H, area]
    return im_info
if __name__ == '__main__':
    image_path = '/home/dlut/網(wǎng)絡(luò)/make_database/數(shù)據(jù)集——合集/VOCdevkit/VOC2018/JPEGImages/'
    xml_path = '/home/dlut/網(wǎng)絡(luò)/make_database/數(shù)據(jù)集——合集/VOCdevkit/VOC2018/Annotations/'
    filenamess = os.listdir(xml_path)
    filenames = []
    for name in filenamess:
        name = name.replace('.xml', '')
        filenames.append(name)
    print(filenames)
    recs = {}
    ims_info = {}
    obs_shape = {}
    classnames = []
    num_objs={}
    obj_avg = {}
    for i, name in enumerate(filenames):
        print('正在處理 {}.xml '.format(name))
        recs[name] = parse_obj(xml_path, name + '.xml')
        print('正在處理 {}.jpg '.format(name))
        ims_info[name] = read_image(image_path, name + '.jpg')
    print('所有信息收集完畢。')
    print('正在處理信息......')
    for name in filenames:
        im_w = ims_info[name][0]
        im_h = ims_info[name][1]
        im_area = ims_info[name][2]
        for object in recs[name]:
            if object['name'] not in num_objs.keys():
                num_objs[object['name']] = 1
            else:
                num_objs[object['name']] += 1
            #num_objs += 1
            ob_w = object['bbox'][2] - object['bbox'][0]
            ob_h = object['bbox'][3] - object['bbox'][1]
            ob_area = ob_w * ob_h
            w_rate = ob_w / im_w
            h_rate = ob_h / im_h
            area_rate = ob_area / im_area
            if not object['name'] in obs_shape.keys():
                obs_shape[object['name']] = ([[ob_w,
                                               ob_h,
                                               ob_area,
                                               w_rate,
                                               h_rate,
                                               area_rate]])
            else:
                obs_shape[object['name']].append([ob_w,
                                                  ob_h,
                                                  ob_area,
                                                  w_rate,
                                                  h_rate,
                                                  area_rate])
        if object['name'] not in classnames:
            classnames.append(object['name'])  # 求平均
    for name in classnames:
        obj_avg[name] = (np.array(obs_shape[name]).sum(axis=0)) / num_objs[name]
        print('{}的情況如下:*******
'.format(name))
        print('  目標(biāo)平均W={}'.format(obj_avg[name][0]))
        print('  目標(biāo)平均H={}'.format(obj_avg[name][1]))
        print('  目標(biāo)平均area={}'.format(obj_avg[name][2]))
        print('  目標(biāo)平均與原圖的W比例={}'.format(obj_avg[name][3]))
        print('  目標(biāo)平均與原圖的H比例={}'.format(obj_avg[name][4]))
        print('  目標(biāo)平均原圖面積占比={}
'.format(obj_avg[name][5]))
    print('信息統(tǒng)計(jì)計(jì)算完畢。')

運(yùn)行結(jié)果

3.修改xml文件中某個(gè)目標(biāo)的名字為另一個(gè)名字

#修改xml文件中的目標(biāo)的名字,
import os, sys
import glob
from xml.etree import ElementTree as ET
# 批量讀取Annotations下的xml文件
# per=ET.parse(r'C:Users
ockhuangDesktopAnnotations