openvino.runtime.opset8.prior_box

openvino.runtime.opset8.prior_box(layer_shape: Node, image_shape: Node | int | float | ndarray, attrs: dict, name: str | None = None) → Node

Generate prior boxes of specified sizes and aspect ratios across all dimensions.

Parameters:

• layer_shape – Shape of layer for which prior boxes are computed.

• image_shape – Shape of image to which prior boxes are scaled.

• attrs – The dictionary containing key, value pairs for attributes.

• name – Optional name for the output node.

Returns:

Node representing prior box operation.

Available attributes are: * min_size The minimum box size (in pixels).

Range of values: positive floating point numbers Default value: [] Required: no

• max_size The maximum box size (in pixels).

  Range of values: positive floating point numbers Default value: [] Required: no

• aspect_ratio Aspect ratios of prior boxes.

  Range of values: set of positive floating point numbers Default value: [] Required: no

• flip The flag that denotes that each aspect_ratio is duplicated and flipped.

  Range of values: {True, False} Default value: False Required: no

• clip The flag that denotes if each value in the output tensor should be clipped

  to [0,1] interval. Range of values: {True, False} Default value: False Required: no

• step The distance between box centers.

  Range of values: floating point non-negative number Default value: 0 Required: no

• offset This is a shift of box respectively to top left corner.

  Range of values: floating point non-negative number Default value: None Required: yes

• variance The variance denotes a variance of adjusting bounding boxes. The attribute

  could contain 0, 1 or 4 elements. Range of values: floating point positive numbers Default value: [] Required: no

• scale_all_sizes The flag that denotes type of inference.

  Range of values: False - max_size is ignored

  True - max_size is used

  Default value: True Required: no

• fixed_ratio This is an aspect ratio of a box.

  Range of values: a list of positive floating-point numbers Default value: None Required: no

• fixed_size This is an initial box size (in pixels).

  Range of values: a list of positive floating-point numbers Default value: None Required: no

• density This is the square root of the number of boxes of each type.

  Range of values: a list of positive floating-point numbers Default value: None Required: no

• min_max_aspect_ratios_order The flag that denotes the order of output prior box.

  Range of values: False - the output prior box is in order of

  [min, aspect_ratios, max]

  True - the output prior box is in order of

  [min, max, aspect_ratios]

  Default value: True Required: no

Example of attribute dictionary:

# just required ones
attrs = {
    'offset': 85,
}
attrs = {
    'offset': 85,
    'flip': True,
    'clip': True,
    'fixed_size': [32, 64, 128]
}

Optional attributes which are absent from dictionary will be set with corresponding default.