code: # --------------------------------------------------------
  # Fast R-CNN
  # Copyright (c) 2015 Microsoft
  # Licensed under The MIT License [see LICENSE for details]
  # Written by Ross Girshick
  # --------------------------------------------------------
  
  import xml.dom.minidom as minidom
  
  import os
  # import PIL
  import numpy as np
  import scipy.sparse
  import subprocess
  import six.moves.cPickle as cPickle
  import math
  import glob
  import uuid
  import scipy.io as sio
  import xml.etree.ElementTree as ET
  
  from .imdb import imdb
  from .imdb import ROOT_DIR
  from datasets import ds_utils
  from .voc_eval import voc_eval
  
  # TODO: make fast_rcnn irrelevant
  # >>>> obsolete, because it depends on sth outside of this project
  from model.utils.config import cfg
  
  
  # <<<< obsolete
  
  
  class pascal_voc(imdb):
      def __init__(self, image_set, year, devkit_path=None):
          imdb.__init__(self, 'voc_' + year + '_' + image_set)
          self._year = year
          self._image_set = image_set
          self._devkit_path = self._get_default_path() if devkit_path is None \
              else devkit_path
          self._data_path = os.path.join(self._devkit_path, 'VOC' + self._year)
          self._classes = ('__background__',  # always index 0
                           'aeroplane', 'bicycle', 'bird', 'boat',
                           'bottle', 'bus', 'car', 'cat', 'chair',
                           'cow', 'diningtable', 'dog', 'horse',
                           'motorbike', 'person', 'pottedplant',
                           'sheep', 'sofa', 'train', 'tvmonitor')
          self._class_to_ind = dict(zip(self.classes, range(self.num_classes)))
          self._image_ext = '.jpg'
          self._image_index = self._load_image_set_index()
          # Default to roidb handler
          # self._roidb_handler = self.selective_search_roidb
          self._roidb_handler = self.gt_roidb
          self._salt = str(uuid.uuid4())
          self._comp_id = 'comp4'
  
          # PASCAL specific config options
          self.config = {'cleanup': True,
                         'use_salt': True,
                         'use_diff': False,
                         'matlab_eval': False,
                         'rpn_file': None,
                         'min_size': 2}
  
          assert os.path.exists(self._devkit_path), \
              'VOCdevkit path does not exist: {}'.format(self._devkit_path)
          assert os.path.exists(self._data_path), \
              'Path does not exist: {}'.format(self._data_path)
  
      def image_path_at(self, i):
          """
          Return the absolute path to image i in the image sequence.
          """
          return self.image_path_from_index(self._image_index[i])
  
      def image_id_at(self, i):
          """
          Return the absolute path to image i in the image sequence.
          """
          return i
  
      def image_path_from_index(self, index):
          """
          Construct an image path from the image's "index" identifier.
          """
          image_path = os.path.join(self._data_path, 'JPEGImages',
                                    index + self._image_ext)
          assert os.path.exists(image_path), \
              'Path does not exist: {}'.format(image_path)
          return image_path
  
      def _load_image_set_index(self):
          """
          Load the indexes listed in this dataset's image set file.
          """
          # Example path to image set file:
          # self._devkit_path + /VOCdevkit2007/VOC2007/ImageSets/Main/val.txt
          image_set_file = os.path.join(self._data_path, 'ImageSets', 'Main',
                                        self._image_set + '.txt')
          assert os.path.exists(image_set_file), \
              'Path does not exist: {}'.format(image_set_file)
          with open(image_set_file) as f:
              image_index = [x.strip() for x in f.readlines()]
          return image_index
  
      def _get_default_path(self):
          """
          Return the default path where PASCAL VOC is expected to be installed.
          """
          return os.path.join(cfg.DATA_DIR, 'VOCdevkit' + self._year)
  
      def gt_roidb(self):
          """
          Return the database of ground-truth regions of interest.
  
          This function loads/saves from/to a cache file to speed up future calls.
          """
          cache_file = os.path.join(self.cache_path, self.name + '_gt_roidb.pkl')
          if os.path.exists(cache_file):
              with open(cache_file, 'rb') as fid:
                  roidb = cPickle.load(fid)
              print('{} gt roidb loaded from {}'.format(self.name, cache_file))
              return roidb
  
          gt_roidb = [self._load_pascal_annotation(index)
                      for index in self.image_index]
          with open(cache_file, 'wb') as fid:
              cPickle.dump(gt_roidb, fid, cPickle.HIGHEST_PROTOCOL)
          print('wrote gt roidb to {}'.format(cache_file))
  
          return gt_roidb
  
      def selective_search_roidb(self):
          """
          Return the database of selective search regions of interest.
          Ground-truth ROIs are also included.
  
          This function loads/saves from/to a cache file to speed up future calls.
          """
          cache_file = os.path.join(self.cache_path,
                                    self.name + '_selective_search_roidb.pkl')
  
          if os.path.exists(cache_file):
              with open(cache_file, 'rb') as fid:
                  roidb = cPickle.load(fid)
              print('{} ss roidb loaded from {}'.format(self.name, cache_file))
              return roidb
  
          if int(self._year) == 2007 or self._image_set != 'test':
              gt_roidb = self.gt_roidb()
              ss_roidb = self._load_selective_search_roidb(gt_roidb)
              roidb = imdb.merge_roidbs(gt_roidb, ss_roidb)
          else:
              roidb = self._load_selective_search_roidb(None)
          with open(cache_file, 'wb') as fid:
              cPickle.dump(roidb, fid, cPickle.HIGHEST_PROTOCOL)
          print('wrote ss roidb to {}'.format(cache_file))
  
          return roidb
  
      def rpn_roidb(self):
          if int(self._year) == 2007 or self._image_set != 'test':
              gt_roidb = self.gt_roidb()
              rpn_roidb = self._load_rpn_roidb(gt_roidb)
              roidb = imdb.merge_roidbs(gt_roidb, rpn_roidb)
          else:
              roidb = self._load_rpn_roidb(None)
  
          return roidb
  
      def _load_rpn_roidb(self, gt_roidb):
          filename = self.config['rpn_file']
          print('loading {}'.format(filename))
          assert os.path.exists(filename), \
              'rpn data not found at: {}'.format(filename)
          with open(filename, 'rb') as f:
              box_list = cPickle.load(f)
          return self.create_roidb_from_box_list(box_list, gt_roidb)
  
      def _load_selective_search_roidb(self, gt_roidb):
          filename = os.path.abspath(os.path.join(cfg.DATA_DIR,
                                                  'selective_search_data',
                                                  self.name + '.mat'))
          assert os.path.exists(filename), \
              'Selective search data not found at: {}'.format(filename)
          raw_data = sio.loadmat(filename)['boxes'].ravel()
  
          box_list = []
          for i in range(raw_data.shape[0]):
              boxes = raw_data[i][:, (1, 0, 3, 2)] - 1
              keep = ds_utils.unique_boxes(boxes)
              boxes = boxes[keep, :]
              keep = ds_utils.filter_small_boxes(boxes, self.config['min_size'])
              boxes = boxes[keep, :]
              box_list.append(boxes)
  
          return self.create_roidb_from_box_list(box_list, gt_roidb)
  
      def _load_pascal_annotation(self, index):
          """
          Load image and bounding boxes info from XML file in the PASCAL VOC
          format.
          """
          filename = os.path.join(self._data_path, 'Annotations', index + '.xml')
          tree = ET.parse(filename)
          objs = tree.findall('object')
          # if not self.config['use_diff']:
          #     # Exclude the samples labeled as difficult
          #     non_diff_objs = [
          #         obj for obj in objs if int(obj.find('difficult').text) == 0]
          #     # if len(non_diff_objs) != len(objs):
          #     #     print 'Removed {} difficult objects'.format(
          #     #         len(objs) - len(non_diff_objs))
          #     objs = non_diff_objs
          num_objs = len(objs)
  
          boxes = np.zeros((num_objs, 4), dtype=np.uint16)
          gt_classes = np.zeros((num_objs), dtype=np.int32)
          overlaps = np.zeros((num_objs, self.num_classes), dtype=np.float32)
          # "Seg" area for pascal is just the box area
          seg_areas = np.zeros((num_objs), dtype=np.float32)
          ishards = np.zeros((num_objs), dtype=np.int32)
  
          # Load object bounding boxes into a data frame.
          for ix, obj in enumerate(objs):
              bbox = obj.find('bndbox')
              # Make pixel indexes 0-based
              x1 = float(bbox.find('xmin').text) - 1
              y1 = float(bbox.find('ymin').text) - 1
              x2 = float(bbox.find('xmax').text) - 1
              y2 = float(bbox.find('ymax').text) - 1
  
              diffc = obj.find('difficult')
              difficult = 0 if diffc == None else int(diffc.text)
              ishards[ix] = difficult
  
              cls = self._class_to_ind[obj.find('name').text.lower().strip()]
              boxes[ix, :] = [x1, y1, x2, y2]
              gt_classes[ix] = cls
              overlaps[ix, cls] = 1.0
              seg_areas[ix] = (x2 - x1 + 1) * (y2 - y1 + 1)
  
          overlaps = scipy.sparse.csr_matrix(overlaps)
  
          return {'boxes': boxes,
                  'gt_classes': gt_classes,
                  'gt_ishard': ishards,
                  'gt_overlaps': overlaps,
                  'flipped': False,
                  'seg_areas': seg_areas}
  
      def _get_comp_id(self):
          comp_id = (self._comp_id + '_' + self._salt if self.config['use_salt']
                     else self._comp_id)
          return comp_id
  
      def _get_voc_results_file_template(self):
          # VOCdevkit/results/VOC2007/Main/<comp_id>_det_test_aeroplane.txt
          filename = self._get_comp_id() + '_det_' + self._image_set + '_{:s}.txt'
          filedir = os.path.join(self._devkit_path, 'results', 'VOC' + self._year, 'Main')
          if not os.path.exists(filedir):
              os.makedirs(filedir)
          path = os.path.join(filedir, filename)
          return path
  
      def _write_voc_results_file(self, all_boxes):
          for cls_ind, cls in enumerate(self.classes):
              if cls == '__background__':
                  continue
              print('Writing {} VOC results file'.format(cls))
              filename = self._get_voc_results_file_template().format(cls)
              with open(filename, 'wt') as f:
                  for im_ind, index in enumerate(self.image_index):
                      dets = all_boxes[cls_ind][im_ind]
                      if dets == []:
                          continue
                      # the VOCdevkit expects 1-based indices
                      for k in range(dets.shape[0]):
                          f.write('{:s} {:.3f} {:.1f} {:.1f} {:.1f} {:.1f}\n'.
                                  format(index, dets[k, -1],
                                         dets[k, 0] + 1, dets[k, 1] + 1,
                                         dets[k, 2] + 1, dets[k, 3] + 1))
  
      def _do_python_eval(self, output_dir='output'):
          annopath = os.path.join(
              self._devkit_path,
              'VOC' + self._year,
              'Annotations',
              '{:s}.xml')
          imagesetfile = os.path.join(
              self._devkit_path,
              'VOC' + self._year,
              'ImageSets',
              'Main',
              self._image_set + '.txt')
          cachedir = os.path.join(self._devkit_path, 'annotations_cache')
          aps = []
          # The PASCAL VOC metric changed in 2010
          use_07_metric = True if int(self._year) < 2010 else False
          print('VOC07 metric? ' + ('Yes' if use_07_metric else 'No'))
          if not os.path.isdir(output_dir):
              os.mkdir(output_dir)
          for i, cls in enumerate(self._classes):
              if cls == '__background__':
                  continue
              filename = self._get_voc_results_file_template().format(cls)
              rec, prec, ap = voc_eval(
                  filename, annopath, imagesetfile, cls, cachedir, ovthresh=0.5,
                  use_07_metric=use_07_metric)
              aps += [ap]
              print('AP for {} = {:.4f}'.format(cls, ap))
              with open(os.path.join(output_dir, cls + '_pr.pkl'), 'w') as f:
                  cPickle.dump({'rec': rec, 'prec': prec, 'ap': ap}, f)
          print('Mean AP = {:.4f}'.format(np.mean(aps)))
          print('~~~~~~~~')
          print('Results:')
          for ap in aps:
              print('{:.3f}'.format(ap))
          print('{:.3f}'.format(np.mean(aps)))
          print('~~~~~~~~')
          print('')
          print('--------------------------------------------------------------')
          print('Results computed with the **unofficial** Python eval code.')
          print('Results should be very close to the official MATLAB eval code.')
          print('Recompute with `./tools/reval.py --matlab ...` for your paper.')
          print('-- Thanks, The Management')
          print('--------------------------------------------------------------')
  
      def _do_matlab_eval(self, output_dir='output'):
          print('-----------------------------------------------------')
          print('Computing results with the official MATLAB eval code.')
          print('-----------------------------------------------------')
          path = os.path.join(cfg.ROOT_DIR, 'lib', 'datasets',
                              'VOCdevkit-matlab-wrapper')
          cmd = 'cd {} && '.format(path)
          cmd += '{:s} -nodisplay -nodesktop '.format(cfg.MATLAB)
          cmd += '-r "dbstop if error; '
          cmd += 'voc_eval(\'{:s}\',\'{:s}\',\'{:s}\',\'{:s}\'); quit;"' \
              .format(self._devkit_path, self._get_comp_id(),
                      self._image_set, output_dir)
          print('Running:\n{}'.format(cmd))
          status = subprocess.call(cmd, shell=True)
  
      def evaluate_detections(self, all_boxes, output_dir):
          self._write_voc_results_file(all_boxes)
          self._do_python_eval(output_dir)
          if self.config['matlab_eval']:
              self._do_matlab_eval(output_dir)
          if self.config['cleanup']:
              for cls in self._classes:
                  if cls == '__background__':
                      continue
                  filename = self._get_voc_results_file_template().format(cls)
                  os.remove(filename)
  
      def competition_mode(self, on):
          if on:
              self.config['use_salt'] = False
              self.config['cleanup'] = False
          else:
              self.config['use_salt'] = True
              self.config['cleanup'] = True
  
  
  if __name__ == '__main__':
      d = pascal_voc('trainval', '2007')
      res = d.roidb
      from IPython import embed;
  
      embed()
  
apis: numpy.mean scipy.io.loadmat numpy.zeros