TensorFlow

API

 tf.keras / layers / layers.Wrapper


Zero-padding layer for 2D input (e.g. picture).

Inherits From: Layer, Module

Used in the notebooks

Used in the tutorials

This layer can add rows and columns of zeros at the top, bottom, left and right side of an image tensor.

Examples:

input_shape = (1, 1, 2, 2)
x = np.arange(np.prod(input_shape)).reshape(input_shape)
print(x)
[[[[0 1]
   [2 3]]]]
y = tf.keras.layers.ZeroPadding2D(padding=1)(x)
print(y)
tf.Tensor(
  [[[[0 0]
     [0 0]
     [0 0]
     [0 0]]
    [[0 0]
     [0 1]
     [2 3]
     [0 0]]
    [[0 0]
     [0 0]
     [0 0]
     [0 0]]]], shape=(1, 3, 4, 2), dtype=int64)

padding Int, or tuple of 2 ints, or tuple of 2 tuples of 2 ints.
  • If int: the same symmetric padding is applied to height and width.
  • If tuple of 2 ints: interpreted as two different symmetric padding values for height and width: (symmetric_height_pad, symmetric_width_pad).
  • If tuple of 2 tuples of 2 ints: interpreted as ((top_pad, bottom_pad), (left_pad, right_pad))
data_format A string, one of channels_last (default) or channels_first. The ordering of the dimensions in the inputs. channels_last corresponds to inputs with shape (batch_size, height, width, channels) while channels_first corresponds to inputs with shape (batch_size, channels, height, width). It defaults to the image_data_format value found in your Keras config file at ~/.keras/keras.json. If you never set it, then it will be "channels_last".

Input shape:

4D tensor with shape:

  • If data_format is "channels_last": (batch_size, rows, cols, channels)
  • If data_format is "channels_first": (batch_size, channels, rows, cols)

Output shape:

4D tensor with shape:

  • If data_format is "channels_last": (batch_size, padded_rows, padded_cols, channels)
  • If data_format is "channels_first": (batch_size, channels, padded_rows, padded_cols)

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