diff --git a/exec.py b/exec.py
index a448a17..ca5e249 100644
--- a/exec.py
+++ b/exec.py
@@ -1,247 +1,254 @@
 #!/usr/bin/env python
 # Copyright 2018 Division of Medical Image Computing, German Cancer Research Center (DKFZ).
 #
 # 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.
 # ==============================================================================
 
 """execution script."""
 
 import argparse
 import os
 import time
 import torch
 
 import utils.exp_utils as utils
 from evaluator import Evaluator
 from predictor import Predictor
 from plotting import plot_batch_prediction
 
 
 def train(logger):
     """
     perform the training routine for a given fold. saves plots and selected parameters to the experiment dir
     specified in the configs.
     """
     logger.info('performing training in {}D over fold {} on experiment {} with model {}'.format(
         cf.dim, cf.fold, cf.exp_dir, cf.model))
 
     net = model.net(cf, logger).cuda()
     optimizer = torch.optim.Adam(net.parameters(), lr=cf.learning_rate[0], weight_decay=cf.weight_decay)
+    if cf.dynamic_lr_scheduling:
+        scheduler = torch.optim.lr_scheduler.ReduceLROnPlateau(optimizer, mode=cf.scheduling_mode, factor=cf.lr_decay_factor,
+                                                               patience=cf.scheduling_patience)
+
     model_selector = utils.ModelSelector(cf, logger)
     train_evaluator = Evaluator(cf, logger, mode='train')
     val_evaluator = Evaluator(cf, logger, mode=cf.val_mode)
 
     starting_epoch = 1
 
     # prepare monitoring
     monitor_metrics = utils.prepare_monitoring(cf)
 
     if cf.resume_to_checkpoint:
         starting_epoch, monitor_metrics = utils.load_checkpoint(cf.resume_to_checkpoint, net, optimizer)
         logger.info('resumed to checkpoint {} at epoch {}'.format(cf.resume_to_checkpoint, starting_epoch))
 
     logger.info('loading dataset and initializing batch generators...')
     batch_gen = data_loader.get_train_generators(cf, logger)
 
     for epoch in range(starting_epoch, cf.num_epochs + 1):
 
         logger.info('starting training epoch {}'.format(epoch))
-        for param_group in optimizer.param_groups:
-            param_group['lr'] = cf.learning_rate[epoch - 1]
-
         start_time = time.time()
 
         net.train()
         train_results_list = []
 
         for bix in range(cf.num_train_batches):
             batch = next(batch_gen['train'])
             tic_fw = time.time()
             results_dict = net.train_forward(batch)
             tic_bw = time.time()
             optimizer.zero_grad()
             results_dict['torch_loss'].backward()
             optimizer.step()
             logger.info('tr. batch {0}/{1} (ep. {2}) fw {3:.2f}s / bw {4:.2f} s / total {5:.2f} s || '
                         .format(bix + 1, cf.num_train_batches, epoch, tic_bw - tic_fw,
                                 time.time() - tic_bw, time.time() - tic_fw) + results_dict['logger_string'])
             train_results_list.append([results_dict['boxes'], batch['pid']])
 
         _, monitor_metrics['train'] = train_evaluator.evaluate_predictions(train_results_list, monitor_metrics['train'])
         #import IPython; IPython.embed()
         train_time = time.time() - start_time
 
         logger.info('starting validation in mode {}.'.format(cf.val_mode))
         with torch.no_grad():
             net.eval()
             if cf.do_validation:
                 val_results_list = []
                 val_predictor = Predictor(cf, net, logger, mode='val')
                 for _ in range(batch_gen['n_val']):
                     batch = next(batch_gen[cf.val_mode])
                     if cf.val_mode == 'val_patient':
                         results_dict = val_predictor.predict_patient(batch)
                     elif cf.val_mode == 'val_sampling':
                         results_dict = net.train_forward(batch, is_validation=True)
                     val_results_list.append([results_dict['boxes'], batch['pid']])
 
                 _, monitor_metrics['val'] = val_evaluator.evaluate_predictions(val_results_list, monitor_metrics['val'])
                 model_selector.run_model_selection(net, optimizer, monitor_metrics, epoch)
 
             # update monitoring and prediction plots
             monitor_metrics.update({"lr":
                                         {str(g): group['lr'] for (g, group) in enumerate(optimizer.param_groups)}})
             logger.metrics2tboard(monitor_metrics, global_step=epoch)
 
             epoch_time = time.time() - start_time
             logger.info('trained epoch {}: took {:.2f} s ({:.2f} s train / {:.2f} s val)'.format(
                 epoch, epoch_time, train_time, epoch_time-train_time))
             batch = next(batch_gen['val_sampling'])
             results_dict = net.train_forward(batch, is_validation=True)
             logger.info('plotting predictions from validation sampling.')
             plot_batch_prediction(batch, results_dict, cf)
 
+        # -------------- scheduling -----------------
+        if cf.dynamic_lr_scheduling:
+            scheduler.step(monitor_metrics["val"][cf.scheduling_criterion][-1])
+        else:
+            for param_group in optimizer.param_groups:
+                param_group['lr'] = cf.learning_rate[epoch-1]
 
 def test(logger):
     """
     perform testing for a given fold (or hold out set). save stats in evaluator.
     """
     logger.info('starting testing model of fold {} in exp {}'.format(cf.fold, cf.exp_dir))
     net = model.net(cf, logger).cuda()
     test_predictor = Predictor(cf, net, logger, mode='test')
     test_evaluator = Evaluator(cf, logger, mode='test')
     batch_gen = data_loader.get_test_generator(cf, logger)
     test_results_list = test_predictor.predict_test_set(batch_gen, return_results=True)
     test_evaluator.evaluate_predictions(test_results_list)
     test_evaluator.score_test_df()
 
 
 if __name__ == '__main__':
     stime = time.time()
 
     parser = argparse.ArgumentParser()
     parser.add_argument('-m', '--mode', type=str,  default='train_test',
                         help='one out of: train / test / train_test / analysis / create_exp')
     parser.add_argument('-f','--folds', nargs='+', type=int, default=None,
                         help='None runs over all folds in CV. otherwise specify list of folds.')
     parser.add_argument('--exp_dir', type=str, default='/path/to/experiment/directory',
                         help='path to experiment dir. will be created if non existent.')
     parser.add_argument('--server_env', default=False, action='store_true',
                         help='change IO settings to deploy models on a cluster.')
     parser.add_argument('--slurm_job_id', type=str, default=None, help='job scheduler info')
     parser.add_argument('--use_stored_settings', default=False, action='store_true',
                         help='load configs from existing exp_dir instead of source dir. always done for testing, '
                              'but can be set to true to do the same for training. useful in job scheduler environment, '
                              'where source code might change before the job actually runs.')
     parser.add_argument('--resume_to_checkpoint', type=str, default=None,
                         help='if resuming to checkpoint, the desired fold still needs to be parsed via --folds.')
     parser.add_argument('--exp_source', type=str, default='experiments/toy_exp',
                         help='specifies, from which source experiment to load configs and data_loader.')
     parser.add_argument('-d', '--dev', default=False, action='store_true', help="development mode: shorten everything")
 
     args = parser.parse_args()
     folds = args.folds
     resume_to_checkpoint = args.resume_to_checkpoint
 
     if args.mode == 'train' or args.mode == 'train_test':
 
         cf = utils.prep_exp(args.exp_source, args.exp_dir, args.server_env, args.use_stored_settings)
         if args.dev:
             folds = [0,1]
             cf.batch_size, cf.num_epochs, cf.min_save_thresh, cf.save_n_models = 3 if cf.dim==2 else 1, 1, 0, 1
             cf.num_train_batches, cf.num_val_batches, cf.max_val_patients = 5, 1, 1
             cf.test_n_epochs =  cf.save_n_models
             cf.max_test_patients = 1
 
         cf.slurm_job_id = args.slurm_job_id
         logger = utils.get_logger(cf.exp_dir, cf.server_env)
         data_loader = utils.import_module('dl', os.path.join(args.exp_source, 'data_loader.py'))
         model = utils.import_module('model', cf.model_path)
         logger.info("loaded model from {}".format(cf.model_path))
         if folds is None:
             folds = range(cf.n_cv_splits)
 
         for fold in folds:
             cf.fold_dir = os.path.join(cf.exp_dir, 'fold_{}'.format(fold))
             cf.fold = fold
             cf.resume_to_checkpoint = resume_to_checkpoint
             if not os.path.exists(cf.fold_dir):
                 os.mkdir(cf.fold_dir)
             logger.set_logfile(fold=fold)
             train(logger)
             cf.resume_to_checkpoint = None
             if args.mode == 'train_test':
                 test(logger)
 
     elif args.mode == 'test':
 
         cf = utils.prep_exp(args.exp_source, args.exp_dir, args.server_env, is_training=False, use_stored_settings=True)
         if args.dev:
             folds = [0,1]
             cf.test_n_epochs =  1; cf.max_test_patients = 1
 
         cf.slurm_job_id = args.slurm_job_id
         logger = utils.get_logger(cf.exp_dir, cf.server_env)
         data_loader = utils.import_module('dl', os.path.join(args.exp_source, 'data_loader.py'))
         model = utils.import_module('model', cf.model_path)
         logger.info("loaded model from {}".format(cf.model_path))
         if folds is None:
             folds = range(cf.n_cv_splits)
 
         for fold in folds:
             cf.fold_dir = os.path.join(cf.exp_dir, 'fold_{}'.format(fold))
             cf.fold = fold
             logger.set_logfile(fold=fold)
             test(logger)
 
 
     # load raw predictions saved by predictor during testing, run aggregation algorithms and evaluation.
     elif args.mode == 'analysis':
         cf = utils.prep_exp(args.exp_source, args.exp_dir, args.server_env, is_training=False, use_stored_settings=True)
         logger = utils.get_logger(cf.exp_dir, cf.server_env)
 
         if cf.hold_out_test_set:
             cf.folds = args.folds
             predictor = Predictor(cf, net=None, logger=logger, mode='analysis')
             results_list = predictor.load_saved_predictions(apply_wbc=True)
             utils.create_csv_output(results_list, cf, logger)
 
         else:
             if folds is None:
                 folds = range(cf.n_cv_splits)
             for fold in folds:
                 cf.fold_dir = os.path.join(cf.exp_dir, 'fold_{}'.format(fold))
                 cf.fold = fold
                 logger.set_logfile(fold=fold)
                 predictor = Predictor(cf, net=None, logger=logger, mode='analysis')
                 results_list = predictor.load_saved_predictions(apply_wbc=True)
                 logger.info('starting evaluation...')
                 evaluator = Evaluator(cf, logger, mode='test')
                 evaluator.evaluate_predictions(results_list)
                 evaluator.score_test_df()
 
     # create experiment folder and copy scripts without starting job.
     # useful for cloud deployment where configs might change before job actually runs.
     elif args.mode == 'create_exp':
         cf = utils.prep_exp(args.exp_source, args.exp_dir, args.server_env, use_stored_settings=True)
         logger = utils.get_logger(cf.exp_dir)
         logger.info('created experiment directory at {}'.format(args.exp_dir))
 
     else:
         raise RuntimeError('mode specified in args is not implemented...')
 
     mins, secs = divmod((time.time() - stime), 60)
     h, mins = divmod(mins, 60)
     t = "{:d}h:{:02d}m:{:02d}s".format(int(h), int(mins), int(secs))
     logger.info("{} total runtime: {}".format(os.path.split(__file__)[1], t))
     del logger
\ No newline at end of file
diff --git a/experiments/toy_exp/configs.py b/experiments/toy_exp/configs.py
index c01c4ca..00e9b95 100644
--- a/experiments/toy_exp/configs.py
+++ b/experiments/toy_exp/configs.py
@@ -1,344 +1,350 @@
 #!/usr/bin/env python
 # Copyright 2018 Division of Medical Image Computing, German Cancer Research Center (DKFZ).
 #
 # 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 sys
 import os
 sys.path.append(os.path.dirname(os.path.realpath(__file__)))
 import numpy as np
 from default_configs import DefaultConfigs
 
 class configs(DefaultConfigs):
 
     def __init__(self, server_env=None):
 
         #########################
         #    Preprocessing      #
         #########################
 
         self.root_dir = '/home/gregor/datasets/toy_mdt'
-        self.pp_noisy_bg = False
 
         #########################
         #         I/O           #
         #########################
 
 
         # one out of [2, 3]. dimension the model operates in.
         self.dim = 2
 
         # one out of ['mrcnn', 'retina_net', 'retina_unet', 'detection_unet', 'ufrcnn'].
-        self.model = 'retina_unet'
+        self.model = 'detection_unet'
 
         DefaultConfigs.__init__(self, self.model, server_env, self.dim)
 
         # int [0 < dataset_size]. select n patients from dataset for prototyping.
         self.select_prototype_subset = None
         self.hold_out_test_set = True
-        self.n_train_data = 1000
+        self.n_train_data = 2500
 
         # choose one of the 3 toy experiments described in https://arxiv.org/pdf/1811.08661.pdf
         # one of ['donuts_shape', 'donuts_pattern', 'circles_scale'].
-        toy_mode = 'donuts_shape'
+        toy_mode = 'donuts_shape_noise'
 
         # path to preprocessed data.
         self.input_df_name = 'info_df.pickle'
         self.pp_name = os.path.join(toy_mode, 'train')
         self.pp_data_path = os.path.join(self.root_dir, self.pp_name)
         self.pp_test_name = os.path.join(toy_mode, 'test')
         self.pp_test_data_path = os.path.join(self.root_dir, self.pp_test_name)
 
         # settings for deployment in cloud.
         if server_env:
             # path to preprocessed data.
             pp_root_dir = '/path/to/data'
             self.pp_name = os.path.join(toy_mode, 'train')
             self.pp_data_path = os.path.join(pp_root_dir, self.pp_name)
             self.pp_test_name = os.path.join(toy_mode, 'test')
             self.pp_test_data_path = os.path.join(pp_root_dir, self.pp_test_name)
             self.select_prototype_subset = None
 
         #########################
         #      Data Loader      #
         #########################
 
         # select modalities from preprocessed data
         self.channels = [0]
         self.n_channels = len(self.channels)
 
         # patch_size to be used for training. pre_crop_size is the patch_size before data augmentation.
         self.pre_crop_size_2D = [320, 320]
         self.patch_size_2D = [320, 320]
 
         self.patch_size = self.patch_size_2D if self.dim == 2 else self.patch_size_3D
         self.pre_crop_size = self.pre_crop_size_2D if self.dim == 2 else self.pre_crop_size_3D
 
         # ratio of free sampled batch elements before class balancing is triggered
         # (>0 to include "empty"/background patches.)
         self.batch_sample_slack = 0.2
 
         # set 2D network to operate in 3D images.
         self.merge_2D_to_3D_preds = False
 
         # feed +/- n neighbouring slices into channel dimension. set to None for no context.
         self.n_3D_context = None
         if self.n_3D_context is not None and self.dim == 2:
             self.n_channels *= (self.n_3D_context * 2 + 1)
 
 
         #########################
         #      Architecture      #
         #########################
 
         self.start_filts = 48 if self.dim == 2 else 18
         self.end_filts = self.start_filts * 4 if self.dim == 2 else self.start_filts * 2
         self.res_architecture = 'resnet50' # 'resnet101' , 'resnet50'
         self.norm = None # one of None, 'instance_norm', 'batch_norm'
-        self.weight_decay = 0
+        self.weight_decay = 1e-4
 
         # one of 'xavier_uniform', 'xavier_normal', or 'kaiming_normal', None (=default = 'kaiming_uniform')
         self.weight_init = None
 
         #########################
         #  Schedule / Selection #
         #########################
 
-        self.num_epochs = 16
+        self.num_epochs = 11
         self.num_train_batches = 100 if self.dim == 2 else 200
         self.batch_size = 20 if self.dim == 2 else 8
 
         self.do_validation = True
         # decide whether to validate on entire patient volumes (like testing) or sampled patches (like training)
         # the former is morge accurate, while the latter is faster (depending on volume size)
         self.val_mode = 'val_patient' # one of 'val_sampling' , 'val_patient'
         if self.val_mode == 'val_patient':
             self.max_val_patients = None  # if 'None' iterates over entire val_set once.
         if self.val_mode == 'val_sampling':
             self.num_val_batches = 50
 
+        # set dynamic_lr_scheduling to True to apply LR scheduling with below settings.
+        self.dynamic_lr_scheduling = True
+        self.lr_decay_factor = 0.5
+        self.scheduling_patience = int(self.num_train_batches * self.batch_size / 2400)
+        self.scheduling_criterion = 'malignant_ap'
+        self.scheduling_mode = 'min' if "loss" in self.scheduling_criterion else 'max'
+
         #########################
         #   Testing / Plotting  #
         #########################
 
         # set the top-n-epochs to be saved for temporal averaging in testing.
         self.save_n_models = 2
         self.test_n_epochs = 2
 
         # set a minimum epoch number for saving in case of instabilities in the first phase of training.
         self.min_save_thresh = 0 if self.dim == 2 else 0
 
         self.report_score_level = ['patient', 'rois']  # choose list from 'patient', 'rois'
         self.class_dict = {1: 'benign', 2: 'malignant'}  # 0 is background.
         self.patient_class_of_interest = 2  # patient metrics are only plotted for one class.
         self.ap_match_ious = [0.1]  # list of ious to be evaluated for ap-scoring.
 
         self.model_selection_criteria = ['benign_ap', 'malignant_ap'] # criteria to average over for saving epochs.
         self.min_det_thresh = 0.1  # minimum confidence value to select predictions for evaluation.
 
         # threshold for clustering predictions together (wcs = weighted cluster scoring).
         # needs to be >= the expected overlap of predictions coming from one model (typically NMS threshold).
         # if too high, preds of the same object are separate clusters.
         self.wcs_iou = 1e-5
 
         self.plot_prediction_histograms = True
         self.plot_stat_curves = False
 
         #########################
         #   Data Augmentation   #
         #########################
 
         self.da_kwargs={
         'do_elastic_deform': True,
         'alpha':(0., 1500.),
         'sigma':(30., 50.),
         'do_rotation':True,
         'angle_x': (0., 2 * np.pi),
         'angle_y': (0., 0),
         'angle_z': (0., 0),
         'do_scale': True,
         'scale':(0.8, 1.1),
         'random_crop':False,
         'rand_crop_dist':  (self.patch_size[0] / 2. - 3, self.patch_size[1] / 2. - 3),
         'border_mode_data': 'constant',
         'border_cval_data': 0,
         'order_data': 1
         }
 
         if self.dim == 3:
             self.da_kwargs['do_elastic_deform'] = False
             self.da_kwargs['angle_x'] = (0, 0.0)
             self.da_kwargs['angle_y'] = (0, 0.0) #must be 0!!
             self.da_kwargs['angle_z'] = (0., 2 * np.pi)
 
 
         #########################
         #   Add model specifics #
         #########################
 
         {'detection_unet': self.add_det_unet_configs,
          'mrcnn': self.add_mrcnn_configs,
          'ufrcnn': self.add_mrcnn_configs,
          'ufrcnn_surrounding': self.add_mrcnn_configs,
          'retina_net': self.add_mrcnn_configs,
          'retina_unet': self.add_mrcnn_configs,
          'prob_detector': self.add_mrcnn_configs,
         }[self.model]()
 
 
     def add_det_unet_configs(self):
 
         self.learning_rate = [1e-4] * self.num_epochs
 
         # aggregation from pixel perdiction to object scores (connected component). One of ['max', 'median']
         self.aggregation_operation = 'max'
 
         # max number of roi candidates to identify per image (slice in 2D, volume in 3D)
         self.n_roi_candidates = 3 if self.dim == 2 else 8
 
         # loss mode: either weighted cross entropy ('wce'), batch-wise dice loss ('dice), or the sum of both ('dice_wce')
         self.seg_loss_mode = 'dice_wce'
 
         # if <1, false positive predictions in foreground are penalized less.
         self.fp_dice_weight = 1 if self.dim == 2 else 1
 
         self.wce_weights = [1, 1, 1]
         self.detection_min_confidence = self.min_det_thresh
 
         # if 'True', loss distinguishes all classes, else only foreground vs. background (class agnostic).
         self.class_specific_seg_flag = True
         self.num_seg_classes = 3 if self.class_specific_seg_flag else 2
         self.head_classes = self.num_seg_classes
 
     def add_mrcnn_configs(self):
 
         # learning rate is a list with one entry per epoch.
         self.learning_rate = [1e-4] * self.num_epochs
 
         # disable mask head loss. (e.g. if no pixelwise annotations available)
         self.frcnn_mode = False
 
         # disable the re-sampling of mask proposals to original size for speed-up.
         # since evaluation is detection-driven (box-matching) and not instance segmentation-driven (iou-matching),
         # mask-outputs are optional.
         self.return_masks_in_val = True
         self.return_masks_in_test = False
 
         # set number of proposal boxes to plot after each epoch.
         self.n_plot_rpn_props = 0 if self.dim == 2 else 0
 
         # number of classes for head networks: n_foreground_classes + 1 (background)
         self.head_classes = 3
 
         # seg_classes hier refers to the first stage classifier (RPN)
         self.num_seg_classes = 2  # foreground vs. background
 
         # feature map strides per pyramid level are inferred from architecture.
         self.backbone_strides = {'xy': [4, 8, 16, 32], 'z': [1, 2, 4, 8]}
 
         # anchor scales are chosen according to expected object sizes in data set. Default uses only one anchor scale
         # per pyramid level. (outer list are pyramid levels (corresponding to BACKBONE_STRIDES), inner list are scales per level.)
         self.rpn_anchor_scales = {'xy': [[8], [16], [32], [64]], 'z': [[2], [4], [8], [16]]}
 
         # choose which pyramid levels to extract features from: P2: 0, P3: 1, P4: 2, P5: 3.
         self.pyramid_levels = [0, 1, 2, 3]
 
         # number of feature maps in rpn. typically lowered in 3D to save gpu-memory.
         self.n_rpn_features = 512 if self.dim == 2 else 128
 
         # anchor ratios and strides per position in feature maps.
         self.rpn_anchor_ratios = [0.5, 1., 2.]
         self.rpn_anchor_stride = 1
 
         # Threshold for first stage (RPN) non-maximum suppression (NMS):  LOWER == HARDER SELECTION
         self.rpn_nms_threshold = 0.7 if self.dim == 2 else 0.7
 
         # loss sampling settings.
         self.rpn_train_anchors_per_image = 2  #per batch element
         self.train_rois_per_image = 2 #per batch element
         self.roi_positive_ratio = 0.5
         self.anchor_matching_iou = 0.7
 
         # factor of top-k candidates to draw from  per negative sample (stochastic-hard-example-mining).
         # poolsize to draw top-k candidates from will be shem_poolsize * n_negative_samples.
         self.shem_poolsize = 10
 
         self.pool_size = (7, 7) if self.dim == 2 else (7, 7, 3)
         self.mask_pool_size = (14, 14) if self.dim == 2 else (14, 14, 5)
         self.mask_shape = (28, 28) if self.dim == 2 else (28, 28, 10)
 
         self.rpn_bbox_std_dev = np.array([0.1, 0.1, 0.1, 0.2, 0.2, 0.2])
         self.bbox_std_dev = np.array([0.1, 0.1, 0.1, 0.2, 0.2, 0.2])
         self.window = np.array([0, 0, self.patch_size[0], self.patch_size[1]])
         self.scale = np.array([self.patch_size[0], self.patch_size[1], self.patch_size[0], self.patch_size[1]])
 
         if self.dim == 2:
             self.rpn_bbox_std_dev = self.rpn_bbox_std_dev[:4]
             self.bbox_std_dev = self.bbox_std_dev[:4]
             self.window = self.window[:4]
             self.scale = self.scale[:4]
 
         # pre-selection in proposal-layer (stage 1) for NMS-speedup. applied per batch element.
         self.pre_nms_limit = 3000 if self.dim == 2 else 6000
 
         # n_proposals to be selected after NMS per batch element. too high numbers blow up memory if "detect_while_training" is True,
         # since proposals of the entire batch are forwarded through second stage in as one "batch".
         self.roi_chunk_size = 800 if self.dim == 2 else 600
         self.post_nms_rois_training = 500 if self.dim == 2 else 75
         self.post_nms_rois_inference = 500
 
         # Final selection of detections (refine_detections)
         self.model_max_instances_per_batch_element = 10 if self.dim == 2 else 30  # per batch element and class.
         self.detection_nms_threshold = 1e-5  # needs to be > 0, otherwise all predictions are one cluster.
         self.model_min_confidence = 0.1
 
         if self.dim == 2:
             self.backbone_shapes = np.array(
                 [[int(np.ceil(self.patch_size[0] / stride)),
                   int(np.ceil(self.patch_size[1] / stride))]
                  for stride in self.backbone_strides['xy']])
         else:
             self.backbone_shapes = np.array(
                 [[int(np.ceil(self.patch_size[0] / stride)),
                   int(np.ceil(self.patch_size[1] / stride)),
                   int(np.ceil(self.patch_size[2] / stride_z))]
                  for stride, stride_z in zip(self.backbone_strides['xy'], self.backbone_strides['z']
                                              )])
         if self.model == 'ufrcnn':
             self.operate_stride1 = True
             self.class_specific_seg_flag = True
             self.num_seg_classes = 3 if self.class_specific_seg_flag else 2
             self.frcnn_mode = True
 
         if self.model == 'retina_net' or self.model == 'retina_unet' or self.model == 'prob_detector':
             # implement extra anchor-scales according to retina-net publication.
             self.rpn_anchor_scales['xy'] = [[ii[0], ii[0] * (2 ** (1 / 3)), ii[0] * (2 ** (2 / 3))] for ii in
                                             self.rpn_anchor_scales['xy']]
             self.rpn_anchor_scales['z'] = [[ii[0], ii[0] * (2 ** (1 / 3)), ii[0] * (2 ** (2 / 3))] for ii in
                                            self.rpn_anchor_scales['z']]
             self.n_anchors_per_pos = len(self.rpn_anchor_ratios) * 3
 
             self.n_rpn_features = 256 if self.dim == 2 else 64
 
             # pre-selection of detections for NMS-speedup. per entire batch.
             self.pre_nms_limit = 10000 if self.dim == 2 else 50000
 
             # anchor matching iou is lower than in Mask R-CNN according to https://arxiv.org/abs/1708.02002
             self.anchor_matching_iou = 0.5
 
             # if 'True', seg loss distinguishes all classes, else only foreground vs. background (class agnostic).
             self.num_seg_classes = 3 if self.class_specific_seg_flag else 2
 
             if self.model == 'retina_unet':
                 self.operate_stride1 = True
diff --git a/experiments/toy_exp/generate_toys.py b/experiments/toy_exp/generate_toys.py
index 4d8acae..7dd4258 100644
--- a/experiments/toy_exp/generate_toys.py
+++ b/experiments/toy_exp/generate_toys.py
@@ -1,130 +1,130 @@
 #!/usr/bin/env python
 # Copyright 2018 Division of Medical Image Computing, German Cancer Research Center (DKFZ).
 #
 # 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 os, time
 import numpy as np
 import pandas as pd
 import pickle
 import argparse
 from multiprocessing import Pool
 
 def multi_processing_create_image(inputs):
 
 
     out_dir, six, foreground_margin, class_diameters, mode, noisy_bg = inputs
     print('processing {} {}'.format(out_dir, six))
 
     img = np.random.rand(320, 320) if noisy_bg else np.zeros((320, 320))
     seg = np.zeros((320, 320)).astype('uint8')
     center_x = np.random.randint(foreground_margin, img.shape[0] - foreground_margin)
     center_y = np.random.randint(foreground_margin, img.shape[1] - foreground_margin)
     class_id = np.random.randint(0, 2)
 
     for y in range(img.shape[0]):
         for x in range(img.shape[0]):
             if ((x - center_x) ** 2 + (y - center_y) ** 2 - class_diameters[class_id] ** 2) < 0:
                 img[y][x] += 0.2
                 seg[y][x] = 1
 
     if 'donuts' in mode:
         hole_diameter = 12
         if class_id == 1:
             for y in range(img.shape[0]):
                 for x in range(img.shape[0]):
                     if ((x - center_x) ** 2 + (y - center_y) ** 2 - hole_diameter ** 2) < 0:
                         img[y][x] -= 0.2
                         if mode == 'donuts_shape':
                             seg[y][x] = 0
 
     out = np.concatenate((img[None], seg[None]))
     out_path = os.path.join(out_dir, '{}.npy'.format(six))
     np.save(out_path, out)
 
     with open(os.path.join(out_dir, 'meta_info_{}.pickle'.format(six)), 'wb') as handle:
         pickle.dump([out_path, class_id, str(six)], handle)
 
 
-def generate_experiment(cf, exp_name, n_train_images, n_test_images, mode, class_diameters=(20, 20)):
+def generate_experiment(cf, exp_name, n_train_images, n_test_images, mode, class_diameters=(20, 20), noisy_bg=False):
 
     train_dir = os.path.join(cf.root_dir, exp_name, 'train')
     test_dir = os.path.join(cf.root_dir, exp_name, 'test')
     os.makedirs(train_dir, exist_ok=True)
     os.makedirs(test_dir, exist_ok=True)
 
     # enforced distance between object center and image edge.
     foreground_margin = int(np.ceil(np.max(class_diameters) / 1.25))
-    noisy_bg = cf.pp_noisy_bg if hasattr(cf, "pp_noisy_bg") else True
 
     info = []
     info += [[train_dir, six, foreground_margin, class_diameters, mode, noisy_bg] for six in range(n_train_images)]
     info += [[test_dir, six, foreground_margin, class_diameters, mode, noisy_bg] for six in range(n_test_images)]
 
     print('starting creation of {} images'.format(len(info)))
     pool = Pool(processes=os.cpu_count()-1)
     pool.map(multi_processing_create_image, info)
     pool.close()
     pool.join()
 
     aggregate_meta_info(train_dir)
     aggregate_meta_info(test_dir)
 
 
 def aggregate_meta_info(exp_dir):
 
     files = [os.path.join(exp_dir, f) for f in os.listdir(exp_dir) if 'meta_info' in f]
     df = pd.DataFrame(columns=['path', 'class_id', 'pid'])
     for f in files:
         with open(f, 'rb') as handle:
             df.loc[len(df)] = pickle.load(handle)
 
     df.to_pickle(os.path.join(exp_dir, 'info_df.pickle'))
     print ("aggregated meta info to df with length", len(df))
 
 
 if __name__ == '__main__':
     stime = time.time()
     import sys
     sys.path.append("../..")
     import utils.exp_utils as utils
 
     parser = argparse.ArgumentParser()
     mode_choices = ['donuts_shape', 'donuts_pattern', 'circles_scale']
     parser.add_argument('-m', '--modes', nargs='+', type=str, default=mode_choices, choices=mode_choices)
+    parser.add_argument('--noise', action='store_true', help="if given, add noise to the sample bg.")
     parser.add_argument('--n_train', type=int, default=1500, help="Nr. of train images to generate.")
     parser.add_argument('--n_test', type=int, default=1000, help="Nr. of test images to generate.")
     args = parser.parse_args()
 
 
     cf_file = utils.import_module("cf", "configs.py")
     cf = cf_file.configs()
 
     class_diameters = {
         'donuts_shape': (20, 20),
         'donuts_pattern': (20, 20),
         'circles_scale': (19, 20)
     }
 
     for mode in args.modes:
-        generate_experiment(cf, mode, n_train_images=args.n_train, n_test_images=args.n_test, mode=mode,
-                            class_diameters=class_diameters[mode])
+        generate_experiment(cf, mode + ("_noise" if args.noise else ""), n_train_images=args.n_train, n_test_images=args.n_test, mode=mode,
+                            class_diameters=class_diameters[mode], noisy_bg=args.noise)
 
 
     mins, secs = divmod((time.time() - stime), 60)
     h, mins = divmod(mins, 60)
     t = "{:d}h:{:02d}m:{:02d}s".format(int(h), int(mins), int(secs))
     print("{} total runtime: {}".format(os.path.split(__file__)[1], t))
 
 
diff --git a/requirements.txt b/requirements.txt
index 4649d7a..2d7d947 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,60 +1,62 @@
 absl-py==0.9.0
 backcall==0.1.0
 batchgenerators==0.19.3
 cachetools==4.0.0
 certifi==2019.11.28
 cffi==1.11.5
 chardet==3.0.4
 cycler==0.10.0
 Cython==0.29.14
 decorator==4.4.1
 future==0.18.2
 google-auth==1.10.0
 google-auth-oauthlib==0.4.1
 grpcio==1.26.0
 idna==2.8
 imageio==2.6.1
+ipython-genutils==0.2.0
 jedi==0.15.1
 joblib==0.14.1
 kiwisolver==1.1.0
 linecache2==1.0.0
 Markdown==3.1.1
 matplotlib==3.1.2
+medicaldetectiontoolkit==0.0.1
 networkx==2.4
 numpy==1.17.4
 oauthlib==3.1.0
 pandas==0.25.3
 parso==0.5.2
 pexpect==4.7.0
 pickleshare==0.7.5
 Pillow==6.2.1
 prompt-toolkit==3.0.2
 protobuf==3.11.2
 ptyprocess==0.6.0
 pyasn1==0.4.8
 pyasn1-modules==0.2.7
 pycparser==2.19
 Pygments==2.5.2
 pyparsing==2.4.5
 python-dateutil==2.8.1
 pytz==2019.3
 PyWavelets==1.1.1
 requests==2.22.0
 requests-oauthlib==1.3.0
 rsa==4.0
 scikit-image==0.16.2
 scikit-learn==0.22.1
 scipy==1.3.3
 six==1.13.0
 sklearn==0.0
 tensorboard==2.1.0
 threadpoolctl==1.1.0
-torch==1.3.1
-torchvision==0.4.2
+torch==1.4.0
+torchvision==0.5.0
 tqdm==4.40.2
 traceback2==1.4.0
 traitlets==4.3.3
 unittest2==1.1.0
 urllib3==1.25.7
 wcwidth==0.1.7
 Werkzeug==0.16.0