diff --git a/examples/ai_fuzzer/lenet5_mnist_coverage.py b/examples/ai_fuzzer/lenet5_mnist_coverage.py
index 4e77a32..27150a5 100644
--- a/examples/ai_fuzzer/lenet5_mnist_coverage.py
+++ b/examples/ai_fuzzer/lenet5_mnist_coverage.py
@@ -14,11 +14,10 @@
 import numpy as np
 from mindspore import Model
 from mindspore import context
-from mindspore.nn import SoftmaxCrossEntropyWithLogits
 from mindspore.train.serialization import load_checkpoint, load_param_into_net
 
-from mindarmour.adv_robustness.attacks import FastGradientSignMethod
-from mindarmour.fuzz_testing import ModelCoverageMetrics
+from mindarmour.fuzz_testing.model_coverage_metrics import NeuronCoverage, TopKNeuronCoverage, NeuronBoundsCoverage,\
+    SuperNeuronActivateCoverage, KMultisectionNeuronCoverage
 from mindarmour.utils.logger import LogUtil
 
 from examples.common.dataset.data_processing import generate_mnist_dataset
@@ -46,13 +45,6 @@ def test_lenet_mnist_coverage():
         images = data[0].astype(np.float32)
         train_images.append(images)
     train_images = np.concatenate(train_images, axis=0)
-    neuron_num = 10
-    segmented_num = 1000
-    top_k = 3
-    threshold = 0.1
-
-    # initialize fuzz test with training dataset
-    model_fuzz_test = ModelCoverageMetrics(model, neuron_num, segmented_num, train_images)
 
     # fuzz test with original test data
     # get test data
@@ -67,31 +59,31 @@ def test_lenet_mnist_coverage():
         test_images.append(images)
         test_labels.append(labels)
     test_images = np.concatenate(test_images, axis=0)
-    test_labels = np.concatenate(test_labels, axis=0)
-    model_fuzz_test.calculate_coverage(test_images)
-    LOGGER.info(TAG, 'KMNC of this test is : %s', model_fuzz_test.get_kmnc())
-    LOGGER.info(TAG, 'NBC of this test is : %s', model_fuzz_test.get_nbc())
-    LOGGER.info(TAG, 'SNAC of this test is : %s', model_fuzz_test.get_snac())
 
-    model_fuzz_test.calculate_effective_coverage(test_images, top_k, threshold)
-    LOGGER.info(TAG, 'NC of this test is : %s', model_fuzz_test.get_nc())
-    LOGGER.info(TAG, 'Effective_NC of this test is : %s', model_fuzz_test.get_effective_nc())
+    # initialize fuzz test with training dataset
+    nc = NeuronCoverage(model, threshold=0.1)
+    nc_metric = nc.get_metrics(test_images)
+
+    tknc = TopKNeuronCoverage(model, top_k=3)
+    tknc_metrics = tknc.get_metrics(test_images)
+
+    snac = SuperNeuronActivateCoverage(model, train_images)
+    snac_metrics = snac.get_metrics(test_images)
+
+    nbc = NeuronBoundsCoverage(model, train_images)
+    nbc_metrics = nbc.get_metrics(test_images)
 
-    # generate adv_data
-    loss = SoftmaxCrossEntropyWithLogits(sparse=True)
-    attack = FastGradientSignMethod(net, eps=0.3, loss_fn=loss)
-    adv_data = attack.batch_generate(test_images, test_labels, batch_size=32)
-    model_fuzz_test.calculate_coverage(adv_data, bias_coefficient=0.5)
-    LOGGER.info(TAG, 'KMNC of this adv data is : %s', model_fuzz_test.get_kmnc())
-    LOGGER.info(TAG, 'NBC of this adv data is : %s', model_fuzz_test.get_nbc())
-    LOGGER.info(TAG, 'SNAC of this adv data is : %s', model_fuzz_test.get_snac())
+    kmnc = KMultisectionNeuronCoverage(model, train_images, segmented_num=100)
+    kmnc_metrics = kmnc.get_metrics(test_images)
 
-    model_fuzz_test.calculate_effective_coverage(adv_data, top_k, threshold)
-    LOGGER.info(TAG, 'NC of this test is : %s', model_fuzz_test.get_nc())
-    LOGGER.info(TAG, 'Effective_NC of this test is : %s', model_fuzz_test.get_effective_nc())
+    print('KMNC of this test is: ', kmnc_metrics)
+    print('NBC of this test is: ', nbc_metrics)
+    print('SNAC of this test is: ', snac_metrics)
+    print('NC of this test is: ', nc_metric)
+    print('TKNC of this test is: ', tknc_metrics)
 
 
 if __name__ == '__main__':
     # device_target can be "CPU", "GPU" or "Ascend"
-    context.set_context(mode=context.GRAPH_MODE, device_target="Ascend")
+    context.set_context(mode=context.GRAPH_MODE, device_target="CPU")
     test_lenet_mnist_coverage()
diff --git a/examples/ai_fuzzer/lenet5_mnist_fuzzing.py b/examples/ai_fuzzer/lenet5_mnist_fuzzing.py
index 7707c44..2c49e39 100644
--- a/examples/ai_fuzzer/lenet5_mnist_fuzzing.py
+++ b/examples/ai_fuzzer/lenet5_mnist_fuzzing.py
@@ -14,11 +14,11 @@
 import numpy as np
 from mindspore import Model
 from mindspore import context
-from mindspore.train.serialization import load_checkpoint, load_param_into_net
+from mindspore import load_checkpoint, load_param_into_net
 
 from mindarmour.fuzz_testing import Fuzzer
-from mindarmour.fuzz_testing import ModelCoverageMetrics
-from mindarmour.utils.logger import LogUtil
+from mindarmour.fuzz_testing import KMultisectionNeuronCoverage
+from mindarmour.utils import LogUtil
 
 from examples.common.dataset.data_processing import generate_mnist_dataset
 from examples.common.networks.lenet5.lenet5_net_for_fuzzing import LeNet5
@@ -52,7 +52,7 @@ def test_lenet_mnist_fuzzing():
                       'params': {'auto_param': [True]}},
                      {'method': 'FGSM',
                       'params': {'eps': [0.3, 0.2, 0.4], 'alpha': [0.1]}}
-                    ]
+                     ]
 
     # get training data
     data_list = "../common/dataset/MNIST/train"
@@ -63,11 +63,6 @@ def test_lenet_mnist_fuzzing():
         images = data[0].astype(np.float32)
         train_images.append(images)
     train_images = np.concatenate(train_images, axis=0)
-    neuron_num = 10
-    segmented_num = 1000
-
-    # initialize fuzz test with training dataset
-    model_coverage_test = ModelCoverageMetrics(model, neuron_num, segmented_num, train_images)
 
     # fuzz test with original test data
     # get test data
@@ -88,21 +83,20 @@ def test_lenet_mnist_fuzzing():
     # make initial seeds
     for img, label in zip(test_images, test_labels):
         initial_seeds.append([img, label])
-
+    coverage = KMultisectionNeuronCoverage(model, train_images, segmented_num=100, incremental=True)
+    kmnc = coverage.get_metrics(test_images[:100])
+    print('KMNC of initial seeds is: ', kmnc)
     initial_seeds = initial_seeds[:100]
-    model_coverage_test.calculate_coverage(
-        np.array(test_images[:100]).astype(np.float32))
-    LOGGER.info(TAG, 'KMNC of this test is : %s',
-                model_coverage_test.get_kmnc())
+    model_fuzz_test = Fuzzer(model)
+    _, _, _, _, metrics = model_fuzz_test.fuzzing(mutate_config, initial_seeds, coverage, evaluate=True, max_iters=10,
+                                                  mutate_num_per_seed=20)
 
-    model_fuzz_test = Fuzzer(model, train_images, neuron_num, segmented_num)
-    _, _, _, _, metrics = model_fuzz_test.fuzzing(mutate_config, initial_seeds, eval_metrics='auto')
     if metrics:
         for key in metrics:
-            LOGGER.info(TAG, key + ': %s', metrics[key])
+            print(key + ': ', metrics[key])
 
 
 if __name__ == '__main__':
-    # device_target can be "CPU", "GPU" or "Ascend"
-    context.set_context(mode=context.GRAPH_MODE, device_target="Ascend")
+    # device_target can be "CPU"GPU, "" or "Ascend"
+    context.set_context(mode=context.GRAPH_MODE, device_target="CPU")
     test_lenet_mnist_fuzzing()
diff --git a/examples/common/networks/lenet5/lenet5_net_for_fuzzing.py b/examples/common/networks/lenet5/lenet5_net_for_fuzzing.py
index 803edd0..ed12d5c 100644
--- a/examples/common/networks/lenet5/lenet5_net_for_fuzzing.py
+++ b/examples/common/networks/lenet5/lenet5_net_for_fuzzing.py
@@ -20,19 +20,21 @@ from mindspore.ops import TensorSummary
 
 
 def conv(in_channels, out_channels, kernel_size, stride=1, padding=0):
+    """Wrap conv."""
     weight = weight_variable()
-    return nn.Conv2d(in_channels, out_channels,
-                     kernel_size=kernel_size, stride=stride, padding=padding,
+    return nn.Conv2d(in_channels, out_channels, kernel_size=kernel_size, stride=stride, padding=padding,
                      weight_init=weight, has_bias=False, pad_mode="valid")
 
 
 def fc_with_initialize(input_channels, out_channels):
+    """Wrap initialize method of full connection layer."""
     weight = weight_variable()
     bias = weight_variable()
     return nn.Dense(input_channels, out_channels, weight, bias)
 
 
 def weight_variable():
+    """Wrap initialize variable."""
     return TruncatedNormal(0.05)
 
 
@@ -50,7 +52,6 @@ class LeNet5(nn.Cell):
         self.relu = nn.ReLU()
         self.max_pool2d = nn.MaxPool2d(kernel_size=2, stride=2)
         self.flatten = nn.Flatten()
-
         self.summary = TensorSummary()
 
     def construct(self, x):
@@ -59,8 +60,6 @@ class LeNet5(nn.Cell):
         Returns:
             x (tensor): network output
         """
-        self.summary('input', x)
-
         x = self.conv1(x)
         self.summary('1', x)
 
diff --git a/mindarmour/fuzz_testing/__init__.py b/mindarmour/fuzz_testing/__init__.py
index 25026dc..871f4c1 100644
--- a/mindarmour/fuzz_testing/__init__.py
+++ b/mindarmour/fuzz_testing/__init__.py
@@ -16,7 +16,13 @@ This module provides a neuron coverage-gain based fuzz method to evaluate the
 robustness of given model.
 """
 from .fuzzing import Fuzzer
-from .model_coverage_metrics import ModelCoverageMetrics
+from .model_coverage_metrics import CoverageMetrics, NeuronCoverage, TopKNeuronCoverage, NeuronBoundsCoverage, \
+    SuperNeuronActivateCoverage, KMultisectionNeuronCoverage
 
 __all__ = ['Fuzzer',
-           'ModelCoverageMetrics']
+           'CoverageMetrics',
+           'NeuronCoverage',
+           'TopKNeuronCoverage',
+           'NeuronBoundsCoverage',
+           'SuperNeuronActivateCoverage',
+           'KMultisectionNeuronCoverage']
diff --git a/mindarmour/fuzz_testing/fuzzing.py b/mindarmour/fuzz_testing/fuzzing.py
index 2ddd9ad..bc57185 100644
--- a/mindarmour/fuzz_testing/fuzzing.py
+++ b/mindarmour/fuzz_testing/fuzzing.py
@@ -21,15 +21,14 @@ from mindspore import Model
 from mindspore import Tensor
 from mindspore import nn
 
-from mindarmour.utils._check_param import check_model, check_numpy_param, \
-    check_param_multi_types, check_norm_level, check_param_in_range, \
-    check_param_type, check_int_positive
+from mindarmour.utils._check_param import check_model, check_numpy_param, check_param_multi_types, check_norm_level, \
+    check_param_in_range, check_param_type, check_int_positive, check_param_bounds
 from mindarmour.utils.logger import LogUtil
 from ..adv_robustness.attacks import FastGradientSignMethod, \
     MomentumDiverseInputIterativeMethod, ProjectedGradientDescent
 from .image_transform import Contrast, Brightness, Blur, \
     Noise, Translate, Scale, Shear, Rotate
-from .model_coverage_metrics import ModelCoverageMetrics
+from .model_coverage_metrics import CoverageMetrics, KMultisectionNeuronCoverage
 
 LOGGER = LogUtil.get_instance()
 TAG = 'Fuzzer'
@@ -43,11 +42,22 @@ def _select_next(initial_seeds):
     return seed, initial_seeds
 
 
-def _coverage_gains(coverages):
-    """ Calculate the coverage gains of mutated samples."""
-    gains = [0] + coverages[:-1]
+def _coverage_gains(pre_coverage, coverages):
+    """
+    Calculate the coverage gains of mutated samples.
+
+    Args:
+        pre_coverage (float): Last value of coverages for previous mutated samples.
+        coverages (list): Coverage of mutated samples.
+
+    Returns:
+        - list, coverage gains for mutated samples.
+
+        - float, last value in parameter coverages.
+    """
+    gains = [pre_coverage] + coverages[:-1]
     gains = np.array(coverages) - np.array(gains)
-    return gains
+    return gains, coverages[-1]
 
 
 def _is_trans_valid(seed, mutate_sample):
@@ -65,37 +75,22 @@ def _is_trans_valid(seed, mutate_sample):
     size = np.shape(diff)[0]
     l0_norm = np.linalg.norm(diff, ord=0)
     linf = np.linalg.norm(diff, ord=np.inf)
-    if l0_norm > pixels_change_rate*size:
+    if l0_norm > pixels_change_rate * size:
         if linf < 256:
             is_valid = True
     else:
-        if linf < pixel_value_change_rate*255:
+        if linf < pixel_value_change_rate * 255:
             is_valid = True
     return is_valid
 
 
-def _check_eval_metrics(eval_metrics):
-    """ Check evaluation metrics."""
-    if isinstance(eval_metrics, (list, tuple)):
-        eval_metrics_ = []
-        available_metrics = ['accuracy', 'attack_success_rate', 'kmnc', 'nbc', 'snac']
-        for elem in eval_metrics:
-            if elem not in available_metrics:
-                msg = 'metric in list `eval_metrics` must be in {}, but got {}.'.format(available_metrics, elem)
-                LOGGER.error(TAG, msg)
-                raise ValueError(msg)
-            eval_metrics_.append(elem.lower())
-    elif isinstance(eval_metrics, str):
-        if eval_metrics != 'auto':
-            msg = "the value of `eval_metrics` must be 'auto' if it's type is str, but got {}.".format(eval_metrics)
-            LOGGER.error(TAG, msg)
-            raise ValueError(msg)
-        eval_metrics_ = 'auto'
+def _gain_threshold(coverage):
+    """Get threshold for given neuron coverage class."""
+    if coverage is isinstance(coverage, KMultisectionNeuronCoverage):
+        gain_threshold = 0.1 / coverage.segmented_num
     else:
-        msg = "the type of `eval_metrics` must be str, list or tuple, but got {}.".format(type(eval_metrics))
-        LOGGER.error(TAG, msg)
-        raise TypeError(msg)
-    return eval_metrics_
+        gain_threshold = 0
+    return gain_threshold
 
 
 class Fuzzer:
@@ -113,6 +108,7 @@ class Fuzzer:
 
     Examples:
         >>> net = Net()
+        >>> model = Model(net)
         >>> mutate_config = [{'method': 'Blur',
         >>>                   'params': {'auto_param': [True]}},
         >>>                  {'method': 'Contrast',
@@ -121,18 +117,15 @@ class Fuzzer:
         >>>                   'params': {'x_bias': [0.1, 0.2], 'y_bias': [0.2]}},
         >>>                  {'method': 'FGSM',
         >>>                   'params': {'eps': [0.1, 0.2, 0.3], 'alpha': [0.1]}}]
-        >>> train_images = np.random.rand(32, 1, 32, 32).astype(np.float32)
-        >>> neuron_num = 10
-        >>> segmented_num = 1000
-        >>> model_fuzz_test = Fuzzer(model, train_images, neuron_num, segmented_num)
-        >>> samples, labels, preds, strategies, report = model_fuzz_test.fuzz_testing(mutate_config, initial_seeds)
+        >>> nc = KMultisectionNeuronCoverage(model, train_images, segmented_num=100)
+        >>> model_fuzz_test = Fuzzer(model)
+        >>> samples, gt_labels, preds, strategies, metrics = model_fuzz_test.fuzzing(mutate_config, initial_seeds,
+        >>>                                                                          nc, max_iters=100)
     """
 
-    def __init__(self, target_model, train_dataset, neuron_num,
-                 segmented_num=1000):
+    def __init__(self, target_model):
         self._target_model = check_model('model', target_model, Model)
-        train_dataset = check_numpy_param('train_dataset', train_dataset)
-        self._coverage_metrics = ModelCoverageMetrics(target_model, neuron_num, segmented_num, train_dataset)
+
         # Allowed mutate strategies so far.
         self._strategies = {'Contrast': Contrast,
                             'Brightness': Brightness,
@@ -161,8 +154,7 @@ class Fuzzer:
                       'prob': {'dtype': [float], 'range': [0, 1]},
                       'bounds': {'dtype': [tuple]}}}
 
-    def fuzzing(self, mutate_config, initial_seeds, coverage_metric='KMNC',
-                eval_metrics='auto', max_iters=10000, mutate_num_per_seed=20):
+    def fuzzing(self, mutate_config, initial_seeds, coverage, evaluate=True, max_iters=10000, mutate_num_per_seed=20):
         """
         Fuzzing tests for deep neural networks.
 
@@ -175,32 +167,20 @@ class Fuzzer:
                 {'method': 'FGSM',
                 'params': {'eps': [0.3, 0.2, 0.4], 'alpha': [0.1]}},
                 ...].
-                The supported methods list is in `self._strategies`, and the
-                params of each method must within the range of optional parameters.　
-                Supported methods are grouped in three types:
-                Firstly, pixel value based transform methods include:
-                'Contrast', 'Brightness', 'Blur' and 'Noise'. Secondly, affine
-                transform methods include: 'Translate', 'Scale', 'Shear' and
-                'Rotate'. Thirdly, attack methods include: 'FGSM', 'PGD' and 'MDIIM'.
-                `mutate_config` must have method in the type of pixel value based
-                transform methods. The way of setting parameters for first and
-                second type methods can be seen in 'mindarmour/fuzz_testing/image_transform.py'.
-                For third type methods, the optional parameters refer to
+                The supported methods list is in `self._strategies`, and the params of each method must within the
+                range of optional parameters. Supported methods are grouped in three types: Firstly, pixel value based
+                transform methods include: 'Contrast', 'Brightness', 'Blur' and 'Noise'. Secondly, affine transform
+                methods include: 'Translate', 'Scale', 'Shear' and 'Rotate'. Thirdly, attack methods include: 'FGSM',
+                'PGD' and 'MDIIM'. `mutate_config` must have method in the type of pixel value based transform methods.
+                The way of setting parameters for first and second type methods can be seen in
+                'mindarmour/fuzz_testing/image_transform.py'. For third type methods, the optional parameters refer to
                 `self._attack_param_checklists`.
-            initial_seeds (list[list]): Initial seeds used to generate mutated
-                samples. The format of initial seeds is [[image_data, label],
-                [...], ...] and the label must be one-hot.
-            coverage_metric (str): Model coverage metric of neural networks. All
-                supported metrics are: 'KMNC', 'NBC', 'SNAC'. Default: 'KMNC'.
-            eval_metrics (Union[list, tuple, str]): Evaluation metrics. If the
-                type is 'auto', it will calculate all the metrics, else if the
-                type is list or tuple, it will calculate the metrics specified
-                by user. All supported evaluate methods are 'accuracy',
-                'attack_success_rate', 'kmnc', 'nbc', 'snac'. Default: 'auto'.
-            max_iters (int): Max number of select a seed to mutate.
-                Default: 10000.
-            mutate_num_per_seed (int): The number of mutate times for a seed.
-                Default: 20.
+            initial_seeds (list[list]): Initial seeds used to generate mutated samples. The format of initial seeds is
+                [[image_data, label], [...], ...] and the label must be one-hot.
+            coverage (CoverageMetrics): Class of neuron coverage metrics.
+            evaluate (bool): return evaluate report or not. Default: True.
+            max_iters (int): Max number of select a seed to mutate. Default: 10000.
+            mutate_num_per_seed (int): The number of mutate times for a seed. Default: 20.
 
         Returns:
             - list, mutated samples in fuzz_testing.
@@ -214,18 +194,18 @@ class Fuzzer:
             - dict, metrics report of fuzzer.
 
         Raises:
-            TypeError: If the type of `eval_metrics` is not str, list or tuple.
-            TypeError: If the type of metric in list `eval_metrics` is not str.
-            ValueError: If `eval_metrics` is not equal to 'auto' when it's type is str.
-            ValueError: If metric in list `eval_metrics` is not in ['accuracy',
-                'attack_success_rate', 'kmnc', 'nbc', 'snac'].
+            ValueError, coverage must be subclass of CoverageMetrics.
+
+            ValueError, if initial seeds is empty.
+
+            ValueError, if element of seed is not two in initial seeds.
         """
         # Check parameters.
-        eval_metrics_ = _check_eval_metrics(eval_metrics)
-        if coverage_metric not in ['KMNC', 'NBC', 'SNAC']:
-            msg = "coverage_metric must be in ['KMNC', 'NBC', 'SNAC'], but got {}.".format(coverage_metric)
+        if not isinstance(coverage, CoverageMetrics):
+            msg = 'coverage must be subclass of CoverageMetrics'
             LOGGER.error(TAG, msg)
             raise ValueError(msg)
+        evaluate = check_param_type('evaluate', evaluate, bool)
         max_iters = check_int_positive('max_iters', max_iters)
         mutate_num_per_seed = check_int_positive('mutate_num_per_seed', mutate_num_per_seed)
         mutate_config = self._check_mutate_config(mutate_config)
@@ -235,15 +215,21 @@ class Fuzzer:
         if not initial_seeds:
             msg = 'initial_seeds must not be empty.'
             raise ValueError(msg)
+        initial_samples = []
         for seed in initial_seeds:
             check_param_type('seed', seed, list)
             if len(seed) != 2:
-                msg = 'seed in initial seeds must have two element image and ' \
-                      'label, but got {} element.'.format(len(seed))
+                msg = 'seed in initial seeds must have two element image and label, but got {} element.'.format(
+                    len(seed))
                 raise ValueError(msg)
             check_numpy_param('seed[0]', seed[0])
             check_numpy_param('seed[1]', seed[1])
+            initial_samples.append(seed[0])
             seed.append(0)
+        initial_samples = np.array(initial_samples)
+        # calculate the coverage of initial seeds
+        pre_coverage = coverage.get_metrics(initial_samples)
+        gain_threshold = _gain_threshold(coverage)
 
         seed, initial_seeds = _select_next(initial_seeds)
         fuzz_samples = []
@@ -253,30 +239,27 @@ class Fuzzer:
         iter_num = 0
         while initial_seeds and iter_num < max_iters:
             # Mutate a seed.
-            mutate_samples, mutate_strategies = self._metamorphic_mutate(seed,
-                                                                         mutates,
-                                                                         mutate_config,
+            mutate_samples, mutate_strategies = self._metamorphic_mutate(seed, mutates, mutate_config,
                                                                          mutate_num_per_seed)
             # Calculate the coverages and predictions of generated samples.
-            coverages, predicts = self._get_coverages_and_predict(mutate_samples, coverage_metric)
-            coverage_gains = _coverage_gains(coverages)
+            coverages, predicts = self._get_coverages_and_predict(mutate_samples, coverage)
+            coverage_gains, pre_coverage = _coverage_gains(pre_coverage, coverages)
             for mutate, cov, pred, strategy in zip(mutate_samples, coverage_gains, predicts, mutate_strategies):
                 fuzz_samples.append(mutate[0])
                 true_labels.append(mutate[1])
                 fuzz_preds.append(pred)
                 fuzz_strategies.append(strategy)
-                # if the mutate samples has coverage gains add this samples in
-                # the initial_seeds to guide new mutates.
-                if cov > 0:
+                # if the mutate samples has coverage gains add this samples in the initial_seeds to guide new mutates.
+                if cov > gain_threshold:
                     initial_seeds.append(mutate)
             seed, initial_seeds = _select_next(initial_seeds)
             iter_num += 1
         metrics_report = None
-        if eval_metrics_ is not None:
-            metrics_report = self._evaluate(fuzz_samples, true_labels, fuzz_preds, fuzz_strategies, eval_metrics_)
+        if evaluate:
+            metrics_report = self._evaluate(fuzz_samples, true_labels, fuzz_preds, fuzz_strategies, coverage)
         return fuzz_samples, true_labels, fuzz_preds, fuzz_strategies, metrics_report
 
-    def _get_coverages_and_predict(self, mutate_samples, coverage_metric="KNMC"):
+    def _get_coverages_and_predict(self, mutate_samples, coverage):
         """ Calculate the coverages and predictions of generated samples."""
         samples = [s[0] for s in mutate_samples]
         samples = np.array(samples)
@@ -285,17 +268,10 @@ class Fuzzer:
         predictions = predictions.asnumpy()
         for index in range(len(samples)):
             mutate = samples[:index + 1]
-            self._coverage_metrics.calculate_coverage(mutate.astype(np.float32))
-            if coverage_metric == 'KMNC':
-                coverages.append(self._coverage_metrics.get_kmnc())
-            if coverage_metric == 'NBC':
-                coverages.append(self._coverage_metrics.get_nbc())
-            if coverage_metric == 'SNAC':
-                coverages.append(self._coverage_metrics.get_snac())
+            coverages.append(coverage.get_metrics(mutate))
         return coverages, predictions
 
-    def _metamorphic_mutate(self, seed, mutates, mutate_config,
-                            mutate_num_per_seed):
+    def _metamorphic_mutate(self, seed, mutates, mutate_config, mutate_num_per_seed):
         """Mutate a seed using strategies random selected from mutate_config."""
         mutate_samples = []
         mutate_strategies = []
@@ -310,8 +286,8 @@ class Fuzzer:
             params = strategy['params']
             method = strategy['method']
             selected_param = {}
-            for p in params:
-                selected_param[p] = choice(params[p])
+            for param in params:
+                selected_param[param] = choice(params[param])
 
             if method in list(self._pixel_value_trans_list + self._affine_trans_list):
                 if method == 'Shear':
@@ -367,8 +343,7 @@ class Fuzzer:
             else:
                 for key in params.keys():
                     check_param_type(str(key), params[key], list)
-        # Methods in `metate_config` should at least have one in the type of
-        # pixel value based transform methods.
+        # Methods in `metate_config` should at least have one in the type of pixel value based transform methods.
         if not has_pixel_trans:
             msg = "mutate methods in mutate_config should at least have one in {}".format(self._pixel_value_trans_list)
             raise ValueError(msg)
@@ -386,17 +361,7 @@ class Fuzzer:
             check_param_type(param_name, params[param_name], list)
             for param_value in params[param_name]:
                 if param_name == 'bounds':
-                    bounds = check_param_multi_types('bounds', param_value, [tuple])
-                    if len(bounds) != 2:
-                        msg = 'The format of bounds must be format (lower_bound, upper_bound),' \
-                              'but got its length as{}'.format(len(bounds))
-                        raise ValueError(msg)
-                    for bound_value in bounds:
-                        _ = check_param_multi_types('bound', bound_value, [int, float])
-                    if bounds[0] >= bounds[1]:
-                        msg = "upper bound must more than lower bound, but upper bound got {}, lower bound " \
-                              "got {}".format(bounds[0], bounds[1])
-                        raise ValueError(msg)
+                    _ = check_param_bounds('bounds', param_name)
                 elif param_name == 'norm_level':
                     _ = check_norm_level(param_value)
                 else:
@@ -420,57 +385,40 @@ class Fuzzer:
                 mutates[method] = self._strategies[method](network, loss_fn=loss_fn)
         return mutates
 
-    def _evaluate(self, fuzz_samples, true_labels, fuzz_preds,
-                  fuzz_strategies, metrics):
+    def _evaluate(self, fuzz_samples, true_labels, fuzz_preds, fuzz_strategies, coverage):
         """
-        Evaluate generated fuzz_testing samples in three dimensions: accuracy,
-        attack success rate and neural coverage.
+        Evaluate generated fuzz_testing samples in three dimensions: accuracy, attack success rate and neural coverage.
 
         Args:
-            fuzz_samples ([numpy.ndarray, list]): Generated fuzz_testing samples
-                according to seeds.
+            fuzz_samples ([numpy.ndarray, list]): Generated fuzz_testing samples according to seeds.
             true_labels ([numpy.ndarray, list]): Ground truth labels of seeds.
             fuzz_preds ([numpy.ndarray, list]): Predictions of generated fuzz samples.
             fuzz_strategies ([numpy.ndarray, list]): Mutate strategies of fuzz samples.
-            metrics (Union[list, tuple, str]): evaluation metrics.
+            coverage (CoverageMetrics): Neuron coverage metrics class.
 
         Returns:
-            dict, evaluate metrics include accuracy, attack success rate
-                and neural coverage.
+            dict, evaluate metrics include accuracy, attack success rate and neural coverage.
         """
+        fuzz_samples = np.array(fuzz_samples)
         true_labels = np.asarray(true_labels)
         fuzz_preds = np.asarray(fuzz_preds)
         temp = np.argmax(true_labels, axis=1) == np.argmax(fuzz_preds, axis=1)
         metrics_report = {}
-        if metrics == 'auto' or 'accuracy' in metrics:
-            if temp.any():
-                acc = np.sum(temp) / np.size(temp)
-            else:
-                acc = 0
-            metrics_report['Accuracy'] = acc
-
-        if metrics == 'auto' or 'attack_success_rate' in metrics:
-            cond = [elem in self._attacks_list for elem in fuzz_strategies]
-            temp = temp[cond]
-            if temp.any():
-                attack_success_rate = 1 - np.sum(temp) / np.size(temp)
-            else:
-                attack_success_rate = None
-            metrics_report['Attack_success_rate'] = attack_success_rate
-
-        if metrics == 'auto' or 'kmnc' in metrics or 'nbc' in metrics or 'snac' in metrics:
-            self._coverage_metrics.calculate_coverage(np.array(fuzz_samples).astype(np.float32))
-
-        if metrics == 'auto' or 'kmnc' in metrics:
-            kmnc = self._coverage_metrics.get_kmnc()
-            metrics_report['Neural_coverage_KMNC'] = kmnc
-
-        if metrics == 'auto' or 'nbc' in metrics:
-            nbc = self._coverage_metrics.get_nbc()
-            metrics_report['Neural_coverage_NBC'] = nbc
 
-        if metrics == 'auto' or 'snac' in metrics:
-            snac = self._coverage_metrics.get_snac()
-            metrics_report['Neural_coverage_SNAC'] = snac
+        if temp.any():
+            acc = np.sum(temp) / np.size(temp)
+        else:
+            acc = 0
+        metrics_report['Accuracy'] = acc
+
+        cond = [elem in self._attacks_list for elem in fuzz_strategies]
+        temp = temp[cond]
+        if temp.any():
+            attack_success_rate = 1 - np.sum(temp) / np.size(temp)
+        else:
+            attack_success_rate = None
+        metrics_report['Attack_success_rate'] = attack_success_rate
+
+        metrics_report['Coverage_metrics'] = coverage.get_metrics(fuzz_samples)
 
         return metrics_report
diff --git a/mindarmour/fuzz_testing/model_coverage_metrics.py b/mindarmour/fuzz_testing/model_coverage_metrics.py
index 24482fa..7b87cd3 100644
--- a/mindarmour/fuzz_testing/model_coverage_metrics.py
+++ b/mindarmour/fuzz_testing/model_coverage_metrics.py
@@ -14,311 +14,396 @@
 """
 Model-Test Coverage Metrics.
 """
-
+from abc import abstractmethod
 from collections import defaultdict
+import math
 import numpy as np
 
 from mindspore import Tensor
 from mindspore import Model
 from mindspore.train.summary.summary_record import _get_summary_tensor_data
 
-from mindarmour.utils._check_param import check_model, check_numpy_param, \
-    check_int_positive, check_param_multi_types
+from mindarmour.utils._check_param import check_model, check_numpy_param, check_int_positive, \
+    check_param_type, check_value_positive
 from mindarmour.utils.logger import LogUtil
 
 LOGGER = LogUtil.get_instance()
-TAG = 'ModelCoverageMetrics'
+TAG = 'CoverageMetrics'
 
 
-class ModelCoverageMetrics:
+class CoverageMetrics:
     """
-    As we all known, each neuron output of a network will have a output range
-    after training (we call it original range), and test dataset is used to
-    estimate the accuracy of the trained network. However, neurons' output
-    distribution would be different with different test datasets. Therefore,
-    similar to function fuzz, model fuzz means testing those neurons' outputs
-    and estimating the proportion of original range that has emerged with test
+    The abstract base class for Neuron coverage classes calculating coverage metrics.
+
+    As we all known, each neuron output of a network will have a output range after training (we call it original
+    range), and test dataset is used to estimate the accuracy of the trained network. However, neurons' output
+    distribution would be different with different test datasets. Therefore, similar to function fuzz, model fuzz means
+    testing those neurons' outputs and estimating the proportion of original range that has emerged with test
     datasets.
 
-    Reference: `DeepGauge: Multi-Granularity Testing Criteria for Deep
-    Learning Systems <https://arxiv.org/abs/1803.07519>`_
+    Reference: `DeepGauge: Multi-Granularity Testing Criteria for Deep Learning Systems
+    <https://arxiv.org/abs/1803.07519>`_
 
     Args:
         model (Model): The pre-trained model which waiting for testing.
-        neuron_num (int): The number of testing neurons.
-        segmented_num (int): The number of segmented sections of neurons' output intervals.
-        train_dataset (numpy.ndarray): Training dataset used for determine
-            the neurons' output boundaries.
-
-    Raises:
-        ValueError: If neuron_num is too big (for example, bigger than 1e+9).
-
-    Examples:
-        >>> net = LeNet5()
-        >>> train_images = np.random.random((10000, 1, 32, 32)).astype(np.float32)
-        >>> test_images = np.random.random((5000, 1, 32, 32)).astype(np.float32)
-        >>> model = Model(net)
-        >>> neuron_num = 10
-        >>> segmented_num = 1000
-        >>> model_fuzz_test = ModelCoverageMetrics(model, neuron_num, segmented_num, train_images)
-        >>> model_fuzz_test.calculate_coverage(test_images)
-        >>> print('KMNC of this test is : %s', model_fuzz_test.get_kmnc())
-        >>> print('NBC of this test is : %s', model_fuzz_test.get_nbc())
-        >>> print('SNAC of this test is : %s', model_fuzz_test.get_snac())
-        >>> model_fuzz_test.calculate_effective_coverage(test_images, top_k, threshold)
-        >>> print('NC of this test is : %s', model_fuzz_test.get_nc())
-        >>> print('Effective_NC of this test is : %s', model_fuzz_test.get_effective_nc())
+        incremental (bool): Metrics will be calculate in incremental way or not. Default: False.
+        batch_size (int):  The number of samples in a fuzz test batch. Default: 32.
     """
 
-    def __init__(self, model, neuron_num, segmented_num, train_dataset):
+    def __init__(self, model, incremental=False, batch_size=32):
         self._model = check_model('model', model, Model)
-        self._segmented_num = check_int_positive('segmented_num', segmented_num)
-        self._neuron_num = check_int_positive('neuron_num', neuron_num)
-        if self._neuron_num > 1e+9:
-            msg = 'neuron_num should be less than 1e+10, otherwise a MemoryError would occur'
-            LOGGER.error(TAG, msg)
-            raise ValueError(msg)
-        train_dataset = check_numpy_param('train_dataset', train_dataset)
-        self._lower_bounds = [np.inf]*self._neuron_num
-        self._upper_bounds = [-np.inf]*self._neuron_num
-        self._var = [0]*self._neuron_num
-        self._main_section_hits = [[0 for _ in range(self._segmented_num)] for _ in range(self._neuron_num)]
-        self._lower_corner_hits = [0]*self._neuron_num
-        self._upper_corner_hits = [0]*self._neuron_num
-        self._bounds_get(train_dataset)
-        self._model_layer_dict = defaultdict(bool)
-        self._effective_model_layer_dict = defaultdict(bool)
-
-    def _set_init_effective_coverage_table(self, dataset):
+        self.incremental = check_param_type('incremental', incremental, bool)
+        self.batch_size = check_int_positive('batch_size', batch_size)
+        self._activate_table = defaultdict(list)
+
+    @abstractmethod
+    def get_metrics(self, dataset):
         """
-        Initialise the coverage table of each neuron in the model.
+        Calculate coverage metrics of given dataset.
 
         Args:
-            dataset (numpy.ndarray): Dataset used for initialising the coverage table.
+            dataset (numpy.ndarray): Dataset used to calculate coverage metrics.
+
+        Raises:
+            NotImplementedError: It is an abstract method.
         """
-        self._model.predict(Tensor(dataset[0:1]))
-        tensors = _get_summary_tensor_data()
-        for name, tensor in tensors.items():
-            if 'input' in name:
-                continue
-            for num_neuron in range(tensor.shape[1]):
-                self._model_layer_dict[(name, num_neuron)] = False
-                self._effective_model_layer_dict[(name, num_neuron)] = False
-
-    def _bounds_get(self, train_dataset, batch_size=32):
+        msg = 'The function get_metrics() is an abstract method in class `CoverageMetrics`, and should be' \
+              ' implemented in child class.'
+        LOGGER.error(TAG, msg)
+        raise NotImplementedError(msg)
+
+    def _init_neuron_activate_table(self, data):
         """
-        Update the lower and upper boundaries of neurons' outputs.
+        Initialise the activate table of each neuron in the model with format:
+        {'layer1': [n1, n2, n3, ..., nn], 'layer2': [n1, n2, n3, ..., nn], ...}
 
         Args:
-            train_dataset (numpy.ndarray): Training dataset used for
-                determine the neurons' output boundaries.
-            batch_size (int): The number of samples in a predict batch.
-                Default: 32.
+            data (numpy.ndarray): Data used for initialising the activate table.
+
+        Return:
+            dict, return a activate_table.
         """
-        batch_size = check_int_positive('batch_size', batch_size)
-        output_mat = []
-        batches = train_dataset.shape[0] // batch_size
-        for i in range(batches):
-            inputs = train_dataset[i*batch_size: (i + 1)*batch_size]
-            output = self._model.predict(Tensor(inputs)).asnumpy()
-            output_mat.append(output)
-            lower_compare_array = np.concatenate([output, np.array([self._lower_bounds])], axis=0)
-            self._lower_bounds = np.min(lower_compare_array, axis=0)
-            upper_compare_array = np.concatenate([output, np.array([self._upper_bounds])], axis=0)
-            self._upper_bounds = np.max(upper_compare_array, axis=0)
-        if batches == 0:
-            output = self._model.predict(Tensor(train_dataset)).asnumpy()
-            self._lower_bounds = np.min(output, axis=0)
-            self._upper_bounds = np.max(output, axis=0)
-            output_mat.append(output)
-        self._var = np.std(np.concatenate(np.array(output_mat), axis=0), axis=0)
-
-    def _sections_hits_count(self, dataset, intervals):
+        self._model.predict(Tensor(data))
+        layer_out = _get_summary_tensor_data()
+        if not layer_out:
+            msg = 'User must use TensorSummary() operation to specify the middle layer of the model participating in ' \
+                  'the coverage calculation.'
+            LOGGER.error(TAG, msg)
+            raise ValueError(msg)
+        activate_table = defaultdict()
+        for layer, value in layer_out.items():
+            activate_table[layer] = np.zeros(value.shape[1], np.bool)
+        return activate_table
+
+    def _get_bounds(self, train_dataset):
         """
-        Update the coverage matrix of neurons' output subsections.
+        Update the lower and upper boundaries of neurons' outputs.
 
         Args:
-            dataset (numpy.ndarray): Testing data.
-            intervals (list[float]): Segmentation intervals of neurons' outputs.
+            train_dataset (numpy.ndarray): Training dataset used for determine the neurons' output boundaries.
+
+        Return:
+            - numpy.ndarray, upper bounds of neuron' outputs.
+
+            - numpy.ndarray, lower bounds of neuron' outputs.
         """
-        dataset = check_numpy_param('dataset', dataset)
-        batch_output = self._model.predict(Tensor(dataset)).asnumpy()
-        batch_section_indexes = (batch_output - self._lower_bounds) // intervals
-        for section_indexes in batch_section_indexes:
-            for i in range(self._neuron_num):
-                if section_indexes[i] < 0:
-                    self._lower_corner_hits[i] = 1
-                elif section_indexes[i] >= self._segmented_num:
-                    self._upper_corner_hits[i] = 1
+        upper_bounds = defaultdict(list)
+        lower_bounds = defaultdict(list)
+        batches = math.ceil(train_dataset.shape[0] / self.batch_size)
+        for i in range(batches):
+            inputs = train_dataset[i * self.batch_size: (i + 1) * self.batch_size]
+            self._model.predict(Tensor(inputs))
+            layer_out = _get_summary_tensor_data()
+            for layer, tensor in layer_out.items():
+                value = tensor.asnumpy()
+                value = np.mean(value, axis=tuple([i for i in range(2, len(value.shape))]))
+                min_value = np.min(value, axis=0)
+                max_value = np.max(value, axis=0)
+                if np.any(upper_bounds[layer]):
+                    max_flag = upper_bounds[layer] > max_value
+                    min_flag = lower_bounds[layer] < min_value
+                    upper_bounds[layer] = upper_bounds[layer] * max_flag + max_value * (1 - max_flag)
+                    lower_bounds[layer] = lower_bounds[layer] * min_flag + min_value * (1 - min_flag)
                 else:
-                    self._main_section_hits[i][int(section_indexes[i])] = 1
+                    upper_bounds[layer] = max_value
+                    lower_bounds[layer] = min_value
+        return upper_bounds, lower_bounds
 
-    def _coverage_update(self, name, tensor, scaled_mean, scaled_rank, top_k, threshold):
+    def _activate_rate(self):
+        """
+        Calculate the activate rate of neurons.
         """
-        Update the coverage matrix of neural coverage and effective neural coverage.
+        total_neurons = 0
+        activated_neurons = 0
+        for _, value in self._activate_table.items():
+            activated_neurons += np.sum(value)
+            total_neurons += len(value)
+        activate_rate = activated_neurons / total_neurons
 
-        Args:
-            name (string): the name of the tensor.
-            tensor (tensor): the tensor in the network.
-            scaled_mean (numpy.ndarray): feature map of the tensor.
-            scaled_rank (numpy.ndarray): rank of tensor value.
-            top_k (int): neuron is covered when its output has the top k largest value in that hidden layer.
-            threshold (float): neuron is covered when its output is greater than the threshold.
+        return activate_rate
 
+
+class NeuronCoverage(CoverageMetrics):
+    """
+    Calculate the neurons activated coverage. Neuron is activated when its output is greater than the threshold.
+    Neuron coverage equals the proportion of activated neurons to total neurons in the network.
+
+    Args:
+        model (Model): The pre-trained model which waiting for testing.
+        threshold (float): Threshold used to determined neurons is activated or not. Default: 0.1.
+        incremental (bool): Metrics will be calculate in incremental way or not. Default: False.
+        batch_size (int):  The number of samples in a fuzz test batch. Default: 32.
+
+    """
+    def __init__(self, model, threshold=0.1, incremental=False, batch_size=32):
+        super(NeuronCoverage, self).__init__(model, incremental, batch_size)
+        self.threshold = check_value_positive('threshold', threshold)
+
+    def get_metrics(self, dataset):
         """
-        for num_neuron in range(tensor.shape[1]):
-            if num_neuron >= (len(scaled_rank) - top_k) and not \
-                    self._effective_model_layer_dict[(name, scaled_rank[num_neuron])]:
-                self._effective_model_layer_dict[(name, scaled_rank[num_neuron])] = True
-            if scaled_mean[num_neuron] > threshold and not \
-                    self._model_layer_dict[(name, num_neuron)]:
-                self._model_layer_dict[(name, num_neuron)] = True
-
-    def calculate_coverage(self, dataset, bias_coefficient=0, batch_size=32):
-        """
-        Calculate the testing adequacy of the given dataset.
+        Get the metric of neuron coverage: the proportion of activated neurons to total neurons in the network.
 
         Args:
-            dataset (numpy.ndarray): Data for fuzz test.
-            bias_coefficient (Union[int, float]): The coefficient used
-                for changing the neurons' output boundaries. Default: 0.
-            batch_size (int): The number of samples in a predict batch. Default: 32.
+            dataset (numpy.ndarray): Dataset used to calculate coverage metrics.
+
+        Returns:
+            float, the metric of 'neuron coverage'.
 
         Examples:
-            >>> neuron_num = 10
-            >>> segmented_num = 1000
-            >>> batch_size = 32
-            >>> model_fuzz_test = ModelCoverageMetrics(model, neuron_num, segmented_num, train_images)
-            >>> model_fuzz_test.calculate_coverage(test_images, top_k, threshold, batch_size)
+            >>> nc = NeuronCoverage(model, threshold=0.1)
+            >>> nc_metrics = nc.get_metrics(test_data)
         """
-
         dataset = check_numpy_param('dataset', dataset)
-        batch_size = check_int_positive('batch_size', batch_size)
-        bias_coefficient = check_param_multi_types('bias_coefficient', bias_coefficient, [int, float])
-        self._lower_bounds -= bias_coefficient*self._var
-        self._upper_bounds += bias_coefficient*self._var
-        intervals = (self._upper_bounds - self._lower_bounds) / self._segmented_num
-        batches = dataset.shape[0] // batch_size
+        batches = math.ceil(dataset.shape[0] / self.batch_size)
+        if not self.incremental or not self._activate_table:
+            self._activate_table = self._init_neuron_activate_table(dataset[0:1])
         for i in range(batches):
-            self._sections_hits_count(dataset[i*batch_size: (i + 1)*batch_size], intervals)
+            inputs = dataset[i * self.batch_size: (i + 1) * self.batch_size]
+            self._model.predict(Tensor(inputs))
+            layer_out = _get_summary_tensor_data()
+            for layer, tensor in layer_out.items():
+                value = tensor.asnumpy()
+                value = np.mean(value, axis=tuple([i for i in range(2, len(value.shape))]))
+                activate = np.sum(value > self.threshold, axis=0) > 0
+                self._activate_table[layer] = np.logical_or(self._activate_table[layer], activate)
+        neuron_coverage = self._activate_rate()
+        return neuron_coverage
+
+
+class TopKNeuronCoverage(CoverageMetrics):
+    """
+    Calculate the top k activated neurons coverage. Neuron is activated when its output has the top k largest value in
+    that hidden layers. Top k neurons coverage equals the proportion of activated neurons to total neurons in the
+    network.
 
+    Args:
+        model (Model): The pre-trained model which waiting for testing.
+        top_k (int): Neuron is activated when its output has the top k largest value in that hidden layers. Default: 3.
+        incremental (bool): Metrics will be calculate in incremental way or not. Default: False.
+        batch_size (int):  The number of samples in a fuzz test batch. Default: 32.
+    """
+    def __init__(self, model, top_k=3, incremental=False, batch_size=32):
+        super(TopKNeuronCoverage, self).__init__(model, incremental=incremental, batch_size=batch_size)
+        self.top_k = check_int_positive('top_k', top_k)
 
-    def calculate_effective_coverage(self, dataset, top_k=3, threshold=0.1, batch_size=32):
+    def get_metrics(self, dataset):
         """
-        Calculate the effective testing adequacy of the given dataset.
-        In effective neural coverage, neuron is covered when its output has the top k largest value
-        in that hidden layers. In neural coverage, neuron is covered when its output is greater than the
-        threshold. Coverage equals the covered neurons divided by the total neurons in the network.
+        Get the metric of Top K activated neuron coverage.
 
         Args:
-            threshold (float): neuron is covered when its output is greater than the threshold.
-            top_k (int): neuron is covered when its output has the top k largest value in that hiddern layer.
-            dataset (numpy.ndarray): Data for fuzz test.
+            dataset (numpy.ndarray): Dataset used to calculate coverage metrics.
+
+        Returns:
+            float, the metrics of 'top k neuron coverage'.
 
         Examples:
-            >>> neuron_num = 10
-            >>> segmented_num = 1000
-            >>> top_k = 3
-            >>> threshold = 0.1
-            >>> model_fuzz_test = ModelCoverageMetrics(model, neuron_num, segmented_num, train_images)
-            >>> model_fuzz_test.calculate_coverage(test_images)
-            >>> model_fuzz_test.calculate_effective_coverage(test_images, top_k, threshold)
+            >>> tknc = TopKNeuronCoverage(model, top_k=3)
+            >>> metrics = tknc.get_metrics(test_data)
         """
-        top_k = check_int_positive('top_k', top_k)
         dataset = check_numpy_param('dataset', dataset)
-        batch_size = check_int_positive('batch_size', batch_size)
-        batches = dataset.shape[0] // batch_size
-        self._set_init_effective_coverage_table(dataset)
+        batches = math.ceil(dataset.shape[0] / self.batch_size)
+        if not self.incremental or not self._activate_table:
+            self._activate_table = self._init_neuron_activate_table(dataset[0:1])
         for i in range(batches):
-            inputs = dataset[i*batch_size: (i + 1)*batch_size]
-            self._model.predict(Tensor(inputs)).asnumpy()
-            tensors = _get_summary_tensor_data()
-            for name, tensor in tensors.items():
-                if 'input' in name:
-                    continue
-                scaled = tensor.asnumpy()[-1]
-                if scaled.ndim >= 3:  #
-                    scaled_mean = np.mean(scaled, axis=(1, 2))
-                    scaled_rank = np.argsort(scaled_mean)
-                    self._coverage_update(name, tensor, scaled_mean, scaled_rank, top_k, threshold)
-                else:
-                    scaled_rank = np.argsort(scaled)
-                    self._coverage_update(name, tensor, scaled, scaled_rank, top_k, threshold)
+            inputs = dataset[i * self.batch_size: (i + 1) * self.batch_size]
+            self._model.predict(Tensor(inputs))
+            layer_out = _get_summary_tensor_data()
+            for layer, tensor in layer_out.items():
+                value = tensor.asnumpy()
+                if len(value.shape) > 2:
+                    value = np.mean(value, axis=tuple([i for i in range(2, len(value.shape))]))
+                top_k_value = np.sort(value)[:, -self.top_k].reshape(value.shape[0], 1)
+                top_k_value = np.sum((value - top_k_value) >= 0, axis=0) > 0
+                self._activate_table[layer] = np.logical_or(self._activate_table[layer], top_k_value)
+        top_k_neuron_coverage = self._activate_rate()
+        return top_k_neuron_coverage
+
+
+class SuperNeuronActivateCoverage(CoverageMetrics):
+    """
+    Get the metric of 'super neuron activation coverage'. :math:`SNAC = |UpperCornerNeuron|/|N|`. SNAC refers to the
+    proportion of neurons whose neurons output value in the test set exceeds the upper bounds of the corresponding
+    neurons output value in the training set.
 
-    def get_nc(self):
+    Args:
+        model (Model): The pre-trained model which waiting for testing.
+        train_dataset (numpy.ndarray): Training dataset used for determine the neurons' output boundaries.
+        incremental (bool): Metrics will be calculate in incremental way or not. Default: False.
+        batch_size (int):  The number of samples in a fuzz test batch. Default: 32.
+    """
+    def __init__(self, model, train_dataset, incremental=False, batch_size=32):
+        super(SuperNeuronActivateCoverage, self).__init__(model, incremental=incremental, batch_size=batch_size)
+        train_dataset = check_numpy_param('train_dataset', train_dataset)
+        self.upper_bounds, self.lower_bounds = self._get_bounds(train_dataset=train_dataset)
+
+    def get_metrics(self, dataset):
         """
-        Get the metric of 'neuron coverage'.
+        Get the metric of 'strong neuron activation coverage'.
+
+        Args:
+            dataset (numpy.ndarray): Dataset used to calculate coverage metrics.
 
         Returns:
-            float, the metric of 'neuron coverage'.
+            float, the metric of 'strong neuron activation coverage'.
 
         Examples:
-            >>> model_fuzz_test.get_nc()
+            >>> snac = SuperNeuronActivateCoverage(model, train_dataset)
+            >>> metrics = snac.get_metrics(test_data)
         """
-        covered_neurons = len([v for v in self._model_layer_dict.values() if v])
-        total_neurons = len(self._model_layer_dict)
-        nc = covered_neurons / float(total_neurons)
-        return nc
+        dataset = check_numpy_param('dataset', dataset)
+        if not self.incremental or not self._activate_table:
+            self._activate_table = self._init_neuron_activate_table(dataset[0:1])
+        batches = math.ceil(dataset.shape[0] / self.batch_size)
 
-    def get_effective_nc(self):
-        """
-        Get the metric of 'effective neuron coverage'.
+        for i in range(batches):
+            inputs = dataset[i * self.batch_size: (i + 1) * self.batch_size]
+            self._model.predict(Tensor(inputs))
+            layer_out = _get_summary_tensor_data()
+            for layer, tensor in layer_out.items():
+                value = tensor.asnumpy()
+                if len(value.shape) > 2:
+                    value = np.mean(value, axis=tuple([i for i in range(2, len(value.shape))]))
+                activate = np.sum(value > self.upper_bounds[layer], axis=0) > 0
+                self._activate_table[layer] = np.logical_or(self._activate_table[layer], activate)
+        snac = self._activate_rate()
+        return snac
 
-        Returns:
-            float, the metric of 'the effective neuron coverage'.
 
-        Examples:
-            >>> model_fuzz_test.get_effective_nc()
-        """
-        covered_neurons = len([v for v in self._effective_model_layer_dict.values() if v])
-        total_neurons = len(self._effective_model_layer_dict)
-        effective_nc = covered_neurons / float(total_neurons)
-        return effective_nc
+class NeuronBoundsCoverage(SuperNeuronActivateCoverage):
+    """
+    Get the metric of 'neuron boundary coverage' :math:`NBC = (|UpperCornerNeuron| + |LowerCornerNeuron|)/(2*|N|)`,
+    where :math`|N|` is the number of neurons, NBC refers to the proportion of neurons whose neurons output value in
+    the test dataset exceeds the upper and lower bounds of the corresponding neurons output value in the training
+    dataset.
 
-    def get_kmnc(self):
-        """
-        Get the metric of 'k-multisection neuron coverage'. KMNC measures how
-        thoroughly the given set of test inputs covers the range of neurons
-        output values derived from training dataset.
+    Args:
+        model (Model): The pre-trained model which waiting for testing.
+        train_dataset (numpy.ndarray): Training dataset used for determine the neurons' output boundaries.
+        incremental (bool): Metrics will be calculate in incremental way or not. Default: False.
+        batch_size (int):  The number of samples in a fuzz test batch. Default: 32.
+    """
 
-        Returns:
-            float, the metric of 'k-multisection neuron coverage'.
+    def __init__(self, model, train_dataset, incremental=False, batch_size=32):
+        super(NeuronBoundsCoverage, self).__init__(model, train_dataset, incremental=incremental, batch_size=batch_size)
 
-        Examples:
-            >>> model_fuzz_test.get_kmnc()
+    def get_metrics(self, dataset):
         """
-        kmnc = np.sum(self._main_section_hits) / (self._neuron_num*self._segmented_num)
-        return kmnc
+        Get the metric of 'neuron boundary coverage'.
 
-    def get_nbc(self):
-        """
-        Get the metric of 'neuron boundary coverage' :math:`NBC = (|UpperCornerNeuron|
-        + |LowerCornerNeuron|)/(2*|N|)`, where :math`|N|` is the number of neurons,
-        NBC refers to the proportion of neurons whose neurons output value in
-        the test dataset exceeds the upper and lower bounds of the corresponding
-        neurons output value in the training dataset.
+        Args:
+            dataset (numpy.ndarray): Dataset used to calculate coverage metrics.
 
         Returns:
             float, the metric of 'neuron boundary coverage'.
 
         Examples:
-            >>> model_fuzz_test.get_nbc()
+            >>> nbc = NeuronBoundsCoverage(model, train_dataset)
+            >>> metrics = nbc.get_metrics(test_data)
         """
-        nbc = (np.sum(self._lower_corner_hits) + np.sum(self._upper_corner_hits)) / (2*self._neuron_num)
+        dataset = check_numpy_param('dataset', dataset)
+        if not self.incremental or not self._activate_table:
+            self._activate_table = self._init_neuron_activate_table(dataset[0:1])
+
+        batches = math.ceil(dataset.shape[0] / self.batch_size)
+        for i in range(batches):
+            inputs = dataset[i * self.batch_size: (i + 1) * self.batch_size]
+            self._model.predict(Tensor(inputs))
+            layer_out = _get_summary_tensor_data()
+            for layer, tensor in layer_out.items():
+                value = tensor.asnumpy()
+                if len(value.shape) > 2:
+                    value = np.mean(value, axis=tuple([i for i in range(2, len(value.shape))]))
+                outer = np.logical_or(value > self.upper_bounds[layer], value < self.lower_bounds[layer])
+                activate = np.sum(outer, axis=0) > 0
+                self._activate_table[layer] = np.logical_or(self._activate_table[layer], activate)
+        nbc = self._activate_rate()
         return nbc
 
-    def get_snac(self):
+
+class KMultisectionNeuronCoverage(SuperNeuronActivateCoverage):
+    """
+    Get the metric of 'k-multisection neuron coverage'. KMNC measures how thoroughly the given set of test inputs
+    covers the range of neurons output values derived from training dataset.
+
+    Args:
+        model (Model): The pre-trained model which waiting for testing.
+        train_dataset (numpy.ndarray): Training dataset used for determine the neurons' output boundaries.
+        segmented_num (int): The number of segmented sections of neurons' output intervals. Default: 100.
+        incremental (bool): Metrics will be calculate in incremental way or not. Default: False.
+        batch_size (int):  The number of samples in a fuzz test batch. Default: 32.
+    """
+
+    def __init__(self, model, train_dataset, segmented_num=100, incremental=False, batch_size=32):
+        super(KMultisectionNeuronCoverage, self).__init__(model, train_dataset, incremental=incremental,
+                                                          batch_size=batch_size)
+        self.segmented_num = check_int_positive('segmented_num', segmented_num)
+        self.intervals = defaultdict(list)
+        for keys in self.upper_bounds.keys():
+            self.intervals[keys] = (self.upper_bounds[keys] - self.lower_bounds[keys]) / self.segmented_num
+
+    def _init_k_multisection_table(self, data):
+        """ Initial the activate table."""
+        self._model.predict(Tensor(data))
+        layer_out = _get_summary_tensor_data()
+        activate_section_table = defaultdict()
+        for layer, value in layer_out.items():
+            activate_section_table[layer] = np.zeros((value.shape[1], self.segmented_num), np.bool)
+        return activate_section_table
+
+    def get_metrics(self, dataset):
         """
-        Get the metric of 'strong neuron activation coverage'.
-        :math:`SNAC = |UpperCornerNeuron|/|N|`. SNAC refers to the proportion
-        of neurons whose neurons output value in the test set exceeds the upper
-        bounds of the corresponding neurons output value in the training set.
+        Get the metric of 'k-multisection neuron coverage'.
+
+        Args:
+            dataset (numpy.ndarray): Dataset used to calculate coverage metrics.
 
         Returns:
-            float, the metric of 'strong neuron activation coverage'.
+            float, the metric of 'k-multisection neuron coverage'.
 
         Examples:
-            >>> model_fuzz_test.get_snac()
+            >>> kmnc = KMultisectionNeuronCoverage(model, train_dataset, segmented_num=100)
+            >>> metrics = kmnc.get_metrics(test_data)
         """
-        snac = np.sum(self._upper_corner_hits) / self._neuron_num
-        return snac
+
+        dataset = check_numpy_param('dataset', dataset)
+        if not self.incremental or not self._activate_table:
+            self._activate_table = self._init_k_multisection_table(dataset[0:1])
+
+        batches = math.ceil(dataset.shape[0] / self.batch_size)
+        for i in range(batches):
+            inputs = dataset[i * self.batch_size: (i + 1) * self.batch_size]
+            self._model.predict(Tensor(inputs))
+            layer_out = _get_summary_tensor_data()
+            for layer, tensor in layer_out.items():
+                value = tensor.asnumpy()
+                value = np.mean(value, axis=tuple([i for i in range(2, len(value.shape))]))
+                hits = np.floor((value - self.lower_bounds[layer]) / self.intervals[layer]).astype(int)
+                hits = np.transpose(hits, [1, 0])
+                for n in range(len(hits)):
+                    for sec in hits[n]:
+                        if sec >= self.segmented_num or sec < 0:
+                            continue
+                        self._activate_table[layer][n][sec] = True
+
+        kmnc = self._activate_rate() / self.segmented_num
+        return kmnc
diff --git a/mindarmour/utils/_check_param.py b/mindarmour/utils/_check_param.py
index 14b5dd7..1892268 100644
--- a/mindarmour/utils/_check_param.py
+++ b/mindarmour/utils/_check_param.py
@@ -39,9 +39,7 @@ def _check_array_not_empty(arg_name, arg_value):
 def check_param_type(arg_name, arg_value, valid_type):
     """Check parameter type."""
     if not isinstance(arg_value, valid_type):
-        msg = '{} must be {}, but got {}'.format(arg_name,
-                                                 valid_type,
-                                                 type(arg_value).__name__)
+        msg = '{} must be {}, but got {}'.format(arg_name, valid_type, type(arg_value).__name__)
         LOGGER.error(TAG, msg)
         raise TypeError(msg)
 
@@ -51,8 +49,7 @@ def check_param_type(arg_name, arg_value, valid_type):
 def check_param_multi_types(arg_name, arg_value, valid_types):
     """Check parameter multi types."""
     if not isinstance(arg_value, tuple(valid_types)):
-        msg = 'type of {} must be in {}, but got {}' \
-            .format(arg_name, valid_types, type(arg_value).__name__)
+        msg = 'type of {} must be in {}, but got {}'.format(arg_name, valid_types, type(arg_value).__name__)
         LOGGER.error(TAG, msg)
         raise TypeError(msg)
 
@@ -68,8 +65,7 @@ def check_int_positive(arg_name, arg_value):
         raise ValueError(msg)
     arg_value = check_param_type(arg_name, arg_value, int)
     if arg_value <= 0:
-        msg = '{} must be greater than 0, but got {}'.format(arg_name,
-                                                             arg_value)
+        msg = '{} must be greater than 0, but got {}'.format(arg_name, arg_value)
         LOGGER.error(TAG, msg)
         raise ValueError(msg)
     return arg_value
@@ -79,8 +75,7 @@ def check_value_non_negative(arg_name, arg_value):
     """Check non negative value."""
     arg_value = check_param_multi_types(arg_name, arg_value, (int, float))
     if float(arg_value) < 0.0:
-        msg = '{} must not be less than 0, but got {}'.format(arg_name,
-                                                              arg_value)
+        msg = '{} must not be less than 0, but got {}'.format(arg_name, arg_value)
         LOGGER.error(TAG, msg)
         raise ValueError(msg)
     return arg_value
@@ -90,8 +85,7 @@ def check_value_positive(arg_name, arg_value):
     """Check positive value."""
     arg_value = check_param_multi_types(arg_name, arg_value, (int, float))
     if float(arg_value) <= 0.0:
-        msg = '{} must be greater than zero, but got {}'.format(arg_name,
-                                                                arg_value)
+        msg = '{} must be greater than zero, but got {}'.format(arg_name, arg_value)
         LOGGER.error(TAG, msg)
         raise ValueError(msg)
     return arg_value
@@ -102,10 +96,7 @@ def check_param_in_range(arg_name, arg_value, lower, upper):
     Check range of parameter.
     """
     if arg_value <= lower or arg_value >= upper:
-        msg = '{} must be between {} and {}, but got {}'.format(arg_name,
-                                                                lower,
-                                                                upper,
-                                                                arg_value)
+        msg = '{} must be between {} and {}, but got {}'.format(arg_name, lower, upper, arg_value)
         LOGGER.error(TAG, msg)
         raise ValueError(msg)
 
@@ -129,10 +120,7 @@ def check_model(model_name, model, model_type):
     """
     if isinstance(model, model_type):
         return model
-    msg = '{} should be an instance of {}, but got {}' \
-        .format(model_name,
-                model_type,
-                type(model).__name__)
+    msg = '{} should be an instance of {}, but got {}'.format(model_name, model_type, type(model).__name__)
     LOGGER.error(TAG, msg)
     raise TypeError(msg)
 
@@ -175,11 +163,9 @@ def check_pair_numpy_param(inputs_name, inputs, labels_name, labels):
         labels (numpy.ndarray): Labels of `inputs`.
 
     Returns:
-        - numpy.ndarray, if `inputs` 's dimension equals to
-          `labels`, return inputs with type of numpy.ndarray.
+        - numpy.ndarray, if `inputs` 's dimension equals to `labels`, return inputs with type of numpy.ndarray.
 
-        - numpy.ndarray, if `inputs` 's dimension equals to
-          `labels` , return labels with type of numpy.ndarray.
+        - numpy.ndarray, if `inputs` 's dimension equals to `labels` , return labels with type of numpy.ndarray.
 
     Raises:
         ValueError: If inputs.shape[0] is not equal to labels.shape[0].
@@ -188,8 +174,7 @@ def check_pair_numpy_param(inputs_name, inputs, labels_name, labels):
     labels = check_numpy_param(labels_name, labels)
     if inputs.shape[0] != labels.shape[0]:
         msg = '{} shape[0] must equal {} shape[0], bot got shape of ' \
-              'inputs {}, shape of labels {}'.format(inputs_name, labels_name,
-                                                     inputs.shape, labels.shape)
+              'inputs {}, shape of labels {}'.format(inputs_name, labels_name, inputs.shape, labels.shape)
         LOGGER.error(TAG, msg)
         raise ValueError(msg)
     return inputs, labels
@@ -198,10 +183,8 @@ def check_pair_numpy_param(inputs_name, inputs, labels_name, labels):
 def check_equal_length(para_name1, value1, para_name2, value2):
     """Check weather the two parameters have equal length."""
     if len(value1) != len(value2):
-        msg = 'The dimension of {0} must equal to the ' \
-              '{1}, but got {0} is {2}, ' \
-              '{1} is {3}'.format(para_name1, para_name2, len(value1),
-                                  len(value2))
+        msg = 'The dimension of {0} must equal to the {1}, but got {0} is {2}, {1} is {3}'\
+            .format(para_name1, para_name2, len(value1), len(value2))
         LOGGER.error(TAG, msg)
         raise ValueError(msg)
     return value1, value2
@@ -210,10 +193,8 @@ def check_equal_length(para_name1, value1, para_name2, value2):
 def check_equal_shape(para_name1, value1, para_name2, value2):
     """Check weather the two parameters have equal shape."""
     if value1.shape != value2.shape:
-        msg = 'The shape of {0} must equal to the ' \
-              '{1}, but got {0} is {2}, ' \
-              '{1} is {3}'.format(para_name1, para_name2, value1.shape,
-                                  value2.shape)
+        msg = 'The shape of {0} must equal to the {1}, but got {0} is {2},  {1} is {3}'.\
+            format(para_name1, para_name2, value1.shape, value2.shape)
         LOGGER.error(TAG, msg)
         raise ValueError(msg)
     return value1, value2
@@ -225,8 +206,7 @@ def check_norm_level(norm_level):
         msg = 'Type of norm_level must be in [int, str], but got {}'.format(type(norm_level))
     accept_norm = [1, 2, '1', '2', 'l1', 'l2', 'inf', 'linf', np.inf]
     if norm_level not in accept_norm:
-        msg = 'norm_level must be in {}, but got {}'.format(accept_norm,
-                                                            norm_level)
+        msg = 'norm_level must be in {}, but got {}'.format(accept_norm, norm_level)
         LOGGER.error(TAG, msg)
         raise ValueError(msg)
     return norm_level
@@ -252,20 +232,16 @@ def normalize_value(value, norm_level):
     value_reshape = value.reshape((value.shape[0], -1))
     avoid_zero_div = 1e-12
     if norm_level in (1, '1', 'l1'):
-        norm = np.linalg.norm(value_reshape, ord=1, axis=1, keepdims=True) + \
-               avoid_zero_div
+        norm = np.linalg.norm(value_reshape, ord=1, axis=1, keepdims=True) + avoid_zero_div
         norm_value = value_reshape / norm
     elif norm_level in (2, '2', 'l2'):
-        norm = np.linalg.norm(value_reshape, ord=2, axis=1, keepdims=True) + \
-               avoid_zero_div
+        norm = np.linalg.norm(value_reshape, ord=2, axis=1, keepdims=True) + avoid_zero_div
         norm_value = value_reshape / norm
     elif norm_level in (np.inf, 'inf'):
-        norm = np.max(abs(value_reshape), axis=1, keepdims=True) + \
-               avoid_zero_div
+        norm = np.max(abs(value_reshape), axis=1, keepdims=True) + avoid_zero_div
         norm_value = value_reshape / norm
     else:
-        msg = 'Values of `norm_level` different from 1, 2 and ' \
-              '`np.inf` are currently not supported, but got {}.' \
+        msg = 'Values of `norm_level` different from 1, 2 and `np.inf` are currently not supported, but got {}.' \
             .format(norm_level)
         LOGGER.error(TAG, msg)
         raise NotImplementedError(msg)
@@ -339,13 +315,30 @@ def check_inputs_labels(inputs, labels):
     inputs_image = inputs[0] if isinstance(inputs, tuple) else inputs
     if isinstance(inputs, tuple):
         for i, inputs_item in enumerate(inputs):
-            _ = check_pair_numpy_param('inputs_image', inputs_image, \
-                'inputs[{}]'.format(i), inputs_item)
+            _ = check_pair_numpy_param('inputs_image', inputs_image, 'inputs[{}]'.format(i), inputs_item)
     if isinstance(labels, tuple):
         for i, labels_item in enumerate(labels):
-            _ = check_pair_numpy_param('inputs', inputs_image, \
-                'labels[{}]'.format(i), labels_item)
+            _ = check_pair_numpy_param('inputs', inputs_image, 'labels[{}]'.format(i), labels_item)
     else:
-        _ = check_pair_numpy_param('inputs', inputs_image, \
-            'labels', labels)
+        _ = check_pair_numpy_param('inputs', inputs_image, 'labels', labels)
     return inputs_image, inputs, labels
+
+
+def check_param_bounds(arg_name, arg_value):
+    """Check bounds is valid"""
+    arg_value = check_param_multi_types(arg_name, arg_value, [tuple, list])
+    if len(arg_value) != 2:
+        msg = 'length of {0} must be 2, but got length of {0} is {1}'.format(arg_name, len(arg_value))
+        LOGGER.error(TAG, msg)
+        raise ValueError(msg)
+    for i, b in enumerate(arg_value):
+        if not isinstance(b, (float, int)):
+            msg = 'each value in {} must be int or float, but got the {}th value is {}'.format(arg_name, i, b)
+            LOGGER.error(TAG, msg)
+            raise ValueError(msg)
+    if arg_value[0] > arg_value[1]:
+        msg = "lower boundary cannot be greater than upper boundary, corresponding values in {} are {} and {}". \
+            format(arg_name, arg_value[0], arg_value[1])
+        LOGGER.error(TAG, msg)
+        raise ValueError(msg)
+    return arg_value
diff --git a/tests/ut/python/fuzzing/test_coverage_metrics.py b/tests/ut/python/fuzzing/test_coverage_metrics.py
index 95f3ee6..61f34b4 100644
--- a/tests/ut/python/fuzzing/test_coverage_metrics.py
+++ b/tests/ut/python/fuzzing/test_coverage_metrics.py
@@ -25,7 +25,8 @@ from mindspore.ops import TensorSummary
 
 from mindarmour.adv_robustness.attacks import FastGradientSignMethod
 from mindarmour.utils.logger import LogUtil
-from mindarmour.fuzz_testing import ModelCoverageMetrics
+from mindarmour.fuzz_testing import NeuronCoverage, TopKNeuronCoverage, SuperNeuronActivateCoverage, \
+    NeuronBoundsCoverage, KMultisectionNeuronCoverage
 
 LOGGER = LogUtil.get_instance()
 TAG = 'Neuron coverage test'
@@ -74,39 +75,48 @@ def test_lenet_mnist_coverage_cpu():
     model = Model(net)
 
     # initialize fuzz test with training dataset
-    neuron_num = 10
-    segmented_num = 1000
-    top_k = 3
-    threshold = 0.1
     training_data = (np.random.random((10000, 10))*20).astype(np.float32)
 
-    model_fuzz_test = ModelCoverageMetrics(model, neuron_num, segmented_num, training_data)
-
     # fuzz test with original test data
     # get test data
     test_data = (np.random.random((2000, 10))*20).astype(np.float32)
     test_labels = np.random.randint(0, 10, 2000).astype(np.int32)
-    model_fuzz_test.calculate_coverage(test_data)
-    LOGGER.info(TAG, 'KMNC of this test is : %s', model_fuzz_test.get_kmnc())
-    LOGGER.info(TAG, 'NBC of this test is : %s', model_fuzz_test.get_nbc())
-    LOGGER.info(TAG, 'SNAC of this test is : %s', model_fuzz_test.get_snac())
 
-    model_fuzz_test.calculate_effective_coverage(test_data, top_k, threshold)
-    LOGGER.info(TAG, 'NC of this test is : %s', model_fuzz_test.get_nc())
-    LOGGER.info(TAG, 'Effective_NC of this test is : %s', model_fuzz_test.get_effective_nc())
+    nc = NeuronCoverage(model, threshold=0.1)
+    nc_metric = nc.get_metrics(test_data)
+
+    tknc = TopKNeuronCoverage(model, top_k=3)
+    tknc_metrics = tknc.get_metrics(test_data)
+
+    snac = SuperNeuronActivateCoverage(model, training_data)
+    snac_metrics = snac.get_metrics(test_data)
+
+    nbc = NeuronBoundsCoverage(model, training_data)
+    nbc_metrics = nbc.get_metrics(test_data)
+
+    kmnc = KMultisectionNeuronCoverage(model, training_data, segmented_num=100)
+    kmnc_metrics = kmnc.get_metrics(test_data)
+
+    print('KMNC of this test is: ', kmnc_metrics)
+    print('NBC of this test is: ', nbc_metrics)
+    print('SNAC of this test is: ', snac_metrics)
+    print('NC of this test is: ', nc_metric)
+    print('TKNC of this test is: ', tknc_metrics)
 
     # generate adv_data
     loss = SoftmaxCrossEntropyWithLogits(sparse=True)
     attack = FastGradientSignMethod(net, eps=0.3, loss_fn=loss)
     adv_data = attack.batch_generate(test_data, test_labels, batch_size=32)
-    model_fuzz_test.calculate_coverage(adv_data, bias_coefficient=0.5)
-    LOGGER.info(TAG, 'KMNC of this test is : %s', model_fuzz_test.get_kmnc())
-    LOGGER.info(TAG, 'NBC of this test is : %s', model_fuzz_test.get_nbc())
-    LOGGER.info(TAG, 'SNAC of this test is : %s', model_fuzz_test.get_snac())
-
-    model_fuzz_test.calculate_effective_coverage(adv_data, top_k, threshold)
-    LOGGER.info(TAG, 'NC of this test is : %s', model_fuzz_test.get_nc())
-    LOGGER.info(TAG, 'Effective_NC of this test is : %s', model_fuzz_test.get_effective_nc())
+    nc_metric = nc.get_metrics(adv_data)
+    tknc_metrics = tknc.get_metrics(adv_data)
+    snac_metrics = snac.get_metrics(adv_data)
+    nbc_metrics = nbc.get_metrics(adv_data)
+    kmnc_metrics = kmnc.get_metrics(adv_data)
+    print('KMNC of adv data is: ', kmnc_metrics)
+    print('NBC of adv data is: ', nbc_metrics)
+    print('SNAC of adv data is: ', snac_metrics)
+    print('NC of adv data is: ', nc_metric)
+    print('TKNC of adv data is: ', tknc_metrics)
 
 @pytest.mark.level0
 @pytest.mark.platform_arm_ascend_training
@@ -120,35 +130,28 @@ def test_lenet_mnist_coverage_ascend():
     model = Model(net)
 
     # initialize fuzz test with training dataset
-    neuron_num = 10
-    segmented_num = 1000
-    top_k = 3
-    threshold = 0.1
     training_data = (np.random.random((10000, 10))*20).astype(np.float32)
-    model_fuzz_test = ModelCoverageMetrics(model, neuron_num, segmented_num, training_data)
 
     # fuzz test with original test data
     # get test data
     test_data = (np.random.random((2000, 10))*20).astype(np.float32)
-    test_labels = np.random.randint(0, 10, 2000)
-    test_labels = (np.eye(10)[test_labels]).astype(np.float32)
-    model_fuzz_test.calculate_coverage(test_data)
-    LOGGER.info(TAG, 'KMNC of this test is : %s', model_fuzz_test.get_kmnc())
-    LOGGER.info(TAG, 'NBC of this test is : %s', model_fuzz_test.get_nbc())
-    LOGGER.info(TAG, 'SNAC of this test is : %s', model_fuzz_test.get_snac())
+    nc = NeuronCoverage(model, threshold=0.1)
+    nc_metric = nc.get_metrics(test_data)
 
-    model_fuzz_test.calculate_effective_coverage(test_data, top_k, threshold)
-    LOGGER.info(TAG, 'NC of this test is : %s', model_fuzz_test.get_nc())
-    LOGGER.info(TAG, 'Effective_NC of this test is : %s', model_fuzz_test.get_effective_nc())
+    tknc = TopKNeuronCoverage(model, top_k=3)
+    tknc_metrics = tknc.get_metrics(test_data)
 
-    # generate adv_data
-    attack = FastGradientSignMethod(net, eps=0.3, loss_fn=nn.SoftmaxCrossEntropyWithLogits(sparse=False))
-    adv_data = attack.batch_generate(test_data, test_labels, batch_size=32)
-    model_fuzz_test.calculate_coverage(adv_data, bias_coefficient=0.5)
-    LOGGER.info(TAG, 'KMNC of this test is : %s', model_fuzz_test.get_kmnc())
-    LOGGER.info(TAG, 'NBC of this test is : %s', model_fuzz_test.get_nbc())
-    LOGGER.info(TAG, 'SNAC of this test is : %s', model_fuzz_test.get_snac())
-
-    model_fuzz_test.calculate_effective_coverage(adv_data, top_k, threshold)
-    LOGGER.info(TAG, 'NC of this test is : %s', model_fuzz_test.get_nc())
-    LOGGER.info(TAG, 'Effective_NC of this test is : %s', model_fuzz_test.get_effective_nc())
+    snac = SuperNeuronActivateCoverage(model, training_data)
+    snac_metrics = snac.get_metrics(test_data)
+
+    nbc = NeuronBoundsCoverage(model, training_data)
+    nbc_metrics = nbc.get_metrics(test_data)
+
+    kmnc = KMultisectionNeuronCoverage(model, training_data, segmented_num=100)
+    kmnc_metrics = kmnc.get_metrics(test_data)
+
+    print('KMNC of this test is: ', kmnc_metrics)
+    print('NBC of this test is: ', nbc_metrics)
+    print('SNAC of this test is: ', snac_metrics)
+    print('NC of this test is: ', nc_metric)
+    print('TKNC of this test is: ', tknc_metrics)
diff --git a/tests/ut/python/fuzzing/test_fuzzer.py b/tests/ut/python/fuzzing/test_fuzzer.py
index 5066bcf..1d585d4 100644
--- a/tests/ut/python/fuzzing/test_fuzzer.py
+++ b/tests/ut/python/fuzzing/test_fuzzer.py
@@ -21,9 +21,10 @@ from mindspore import nn
 from mindspore.common.initializer import TruncatedNormal
 from mindspore.ops import operations as P
 from mindspore.train import Model
+from mindspore.ops import TensorSummary
 
 from mindarmour.fuzz_testing import Fuzzer
-from mindarmour.fuzz_testing import ModelCoverageMetrics
+from mindarmour.fuzz_testing import KMultisectionNeuronCoverage
 from mindarmour.utils.logger import LogUtil
 
 LOGGER = LogUtil.get_instance()
@@ -52,30 +53,37 @@ class Net(nn.Cell):
     """
     Lenet network
     """
+
     def __init__(self):
         super(Net, self).__init__()
         self.conv1 = conv(1, 6, 5)
         self.conv2 = conv(6, 16, 5)
-        self.fc1 = fc_with_initialize(16*5*5, 120)
+        self.fc1 = fc_with_initialize(16 * 5 * 5, 120)
         self.fc2 = fc_with_initialize(120, 84)
         self.fc3 = fc_with_initialize(84, 10)
         self.relu = nn.ReLU()
         self.max_pool2d = nn.MaxPool2d(kernel_size=2, stride=2)
         self.reshape = P.Reshape()
+        self.summary = TensorSummary()
 
     def construct(self, x):
         x = self.conv1(x)
         x = self.relu(x)
+        self.summary('conv1', x)
         x = self.max_pool2d(x)
         x = self.conv2(x)
         x = self.relu(x)
+        self.summary('conv2', x)
         x = self.max_pool2d(x)
-        x = self.reshape(x, (-1, 16*5*5))
+        x = self.reshape(x, (-1, 16 * 5 * 5))
         x = self.fc1(x)
         x = self.relu(x)
+        self.summary('fc1', x)
         x = self.fc2(x)
         x = self.relu(x)
+        self.summary('fc2', x)
         x = self.fc3(x)
+        self.summary('fc3', x)
         return x
 
 
@@ -100,12 +108,8 @@ def test_fuzzing_ascend():
                      {'method': 'FGSM',
                       'params': {'eps': [0.1, 0.2, 0.3], 'alpha': [0.1]}}
                      ]
-    # initialize fuzz test with training dataset
-    neuron_num = 10
-    segmented_num = 1000
-    train_images = np.random.rand(32, 1, 32, 32).astype(np.float32)
-    model_coverage_test = ModelCoverageMetrics(model, neuron_num, segmented_num, train_images)
 
+    train_images = np.random.rand(32, 1, 32, 32).astype(np.float32)
     # fuzz test with original test data
     # get test data
     test_images = np.random.rand(batch_size, 1, 32, 32).astype(np.float32)
@@ -118,13 +122,12 @@ def test_fuzzing_ascend():
         initial_seeds.append([img, label])
 
     initial_seeds = initial_seeds[:100]
-    model_coverage_test.calculate_coverage(
-        np.array(test_images[:100]).astype(np.float32))
-    LOGGER.info(TAG, 'KMNC of this test is : %s',
-                model_coverage_test.get_kmnc())
 
-    model_fuzz_test = Fuzzer(model, train_images, neuron_num, segmented_num)
-    _, _, _, _, metrics = model_fuzz_test.fuzzing(mutate_config, initial_seeds)
+    nc = KMultisectionNeuronCoverage(model, train_images, segmented_num=100)
+    cn_metrics = nc.get_metrics(test_images[:100])
+    print('neuron coverage of initial seeds is: ', cn_metrics)
+    model_fuzz_test = Fuzzer(model)
+    _, _, _, _, metrics = model_fuzz_test.fuzzing(mutate_config, initial_seeds, nc, max_iters=100)
     print(metrics)
 
 
@@ -139,8 +142,6 @@ def test_fuzzing_cpu():
     model = Model(net)
     batch_size = 8
     num_classe = 10
-    neuron_num = 10
-    segmented_num = 1000
     mutate_config = [{'method': 'Blur',
                       'params': {'auto_param': [True]}},
                      {'method': 'Contrast',
@@ -152,7 +153,6 @@ def test_fuzzing_cpu():
                      ]
     # initialize fuzz test with training dataset
     train_images = np.random.rand(32, 1, 32, 32).astype(np.float32)
-    model_coverage_test = ModelCoverageMetrics(model, neuron_num, segmented_num, train_images)
 
     # fuzz test with original test data
     # get test data
@@ -166,11 +166,9 @@ def test_fuzzing_cpu():
         initial_seeds.append([img, label])
 
     initial_seeds = initial_seeds[:100]
-    model_coverage_test.calculate_coverage(
-        np.array(test_images[:100]).astype(np.float32))
-    LOGGER.info(TAG, 'KMNC of this test is : %s',
-                model_coverage_test.get_kmnc())
-
-    model_fuzz_test = Fuzzer(model, train_images, neuron_num, segmented_num)
-    _, _, _, _, metrics = model_fuzz_test.fuzzing(mutate_config, initial_seeds)
+    nc = KMultisectionNeuronCoverage(model, train_images, segmented_num=100)
+    tknc_metrics = nc.get_metrics(test_images[:100])
+    print('neuron coverage of initial seeds is: ', tknc_metrics)
+    model_fuzz_test = Fuzzer(model)
+    _, _, _, _, metrics = model_fuzz_test.fuzzing(mutate_config, initial_seeds, nc, max_iters=100)
     print(metrics)