tensorflow/models · error · ValueError

Unsupported activation `{}`.

Error message

Unsupported activation `{}`.

What it means

Error "Unsupported activation `{}`." thrown in tensorflow/models.

Source

Thrown at official/legacy/detection/modeling/architecture/fpn.py:73

      activation: the activation function.
      use_batch_norm: 'bool', indicating whether batchnorm layers are added.
      norm_activation: an operation that includes a normalization layer
        followed by an optional activation layer.
    """
    self._min_level = min_level
    self._max_level = max_level
    self._fpn_feat_dims = fpn_feat_dims
    if use_separable_conv:
      self._conv2d_op = functools.partial(
          tf_keras.layers.SeparableConv2D, depth_multiplier=1)
    else:
      self._conv2d_op = tf_keras.layers.Conv2D
    if activation == 'relu':
      self._activation_op = tf.nn.relu
    elif activation == 'swish':
      self._activation_op = tf.nn.swish
    else:
      raise ValueError('Unsupported activation `{}`.'.format(activation))
    self._use_batch_norm = use_batch_norm
    self._norm_activation = norm_activation

    self._norm_activations = {}
    self._lateral_conv2d_op = {}
    self._post_hoc_conv2d_op = {}
    self._coarse_conv2d_op = {}
    for level in range(self._min_level, self._max_level + 1):
      if self._use_batch_norm:
        self._norm_activations[level] = norm_activation(
            use_activation=False, name='p%d-bn' % level)
      self._lateral_conv2d_op[level] = self._conv2d_op(
          filters=self._fpn_feat_dims,
          kernel_size=(1, 1),
          padding='same',
          name='l%d' % level)
      self._post_hoc_conv2d_op[level] = self._conv2d_op(
          filters=self._fpn_feat_dims,

View on GitHub (pinned to e006f5f0d5)

When it happens

Trigger: Thrown at official/legacy/detection/modeling/architecture/fpn.py:73 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of tensorflow/models@e006f5f0d5 (2026-08-24). Data as JSON: /api/errors/7d48995fa81d08dd. Report an issue: GitHub.