EasyCV/easycv/core/evaluation/classification_eval.py

75 lines
2.5 KiB
Python

# Copyright (c) Alibaba, Inc. and its affiliates.
from collections import OrderedDict
from .base_evaluator import Evaluator
from .builder import EVALUATORS
from .metric_registry import METRICS
@EVALUATORS.register_module
class ClsEvaluator(Evaluator):
""" Classification evaluator.
"""
def __init__(self,
topk=(1, 5),
dataset_name=None,
metric_names=['neck_top1'],
neck_num=None):
'''
Args:
top_k: tuple of int, evaluate top_k acc
dataset_name: eval dataset name
metric_names: eval metrics name
neck_num: some model contains multi-neck to support multitask, neck_num means use the no.neck_num neck output of model to eval
'''
self._topk = topk
self.dataset_name = dataset_name
self.neck_num = neck_num
super(ClsEvaluator, self).__init__(dataset_name, metric_names)
def _evaluate_impl(self, predictions, gt_labels):
''' python evaluation code which will be run after all test batched data are predicted
Args:
predictions: dict of tensor with shape NxC, from each cls heads
gt_labels: int32 tensor with shape N
Return:
a dict, each key is metric_name, value is metric value
'''
eval_res = OrderedDict()
target = gt_labels.long()
# if self.neck_num is not None:
if self.neck_num is None:
predictions = {'neck': predictions['neck']}
else:
predictions = {
'neck_%d_0' % self.neck_num:
predictions['neck_%d_0' % self.neck_num]
}
for key, scores in predictions.items():
assert scores.size(0) == target.size(0), \
'Inconsistent length for results and labels, {} vs {}'.format(
scores.size(0), target.size(0))
num = scores.size(0)
_, pred = scores.topk(
max(self._topk), dim=1, largest=True, sorted=True)
pred = pred.t()
correct = pred.eq(target.view(1, -1).expand_as(pred)) # KxN
for k in self._topk:
# use contiguous() to avoid eval view failed
correct_k = correct[:k].contiguous().view(-1).float().sum(
0).item()
acc = correct_k * 100.0 / num
eval_res['{}_top{}'.format(key, k)] = acc
return eval_res
METRICS.register_default_best_metric(ClsEvaluator, 'neck_top1', 'max')