class_docstr: Computes pixAcc and mIoU metric scores
      
class_docstr_tok: ["Computes","pixAcc","and","mIoU","metric","scores"]
code: def __init__(self, nclass):
      super(SegmentationMetric, self).__init__("pixAcc & mIoU")
      self.nclass = nclass
      self.lock = threading.Lock()
      self.reset()
  
file_path: gluon-cv/gluoncv/utils/metrics/segmentation.py
imports: import threading
  import numpy
  import mxnet
label_desc: Use image node_id 1 to create a new SegmentationMetric object from inherited base classes: EvalMetric with example: obj = SegmentationMetric(nclass)