utils

LiteRT Utility API

This module provides utility functions for working with the LiteRT schema.

Classes:

• BuiltinOperatorMap –

  Mapping of builtin operator codes to their names.

• BuiltinOptionsMap –

  Mapping of builtin options codes to their names.

Functions:

• get_builtin_code –

  Return the builtin code of the given operator code.

• compute_tensor_bytes –

  Compute the number of bytes for a tensor based on its type and shape.

• compute_tensor_ctype –

  Compute the C type for a tensor based on its type.

• get_tensor_dtype –

  Get the numpy dtype of a tensor.

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Functions

get_builtin_code

get_builtin_code(opcode: OperatorCodeT | OperatorCode) -> int

Return the builtin code of the given operator code.

This function serves as a workaround for older versions of LiteRT that do not support/populate the BuiltinCode property.

Parameters:

• opcode

  (OperatorCodeT | OperatorCode) –

  Operator code.

Returns:

• int ( int ) –

  Builtin code.

compute_tensor_bytes

compute_tensor_bytes(tensor: TensorT) -> int

Compute the number of bytes for a tensor based on its type and shape.

Parameters:

• tensor

  (TensorT) –

  Tensor object.

Returns:

• int ( int ) –

  Number of bytes for the tensor.

compute_tensor_ctype

compute_tensor_ctype(tensor: TensorT) -> str

Compute the C type for a tensor based on its type.

Parameters:

• tensor

  (TensorT) –

  Tensor object.

Returns:

• str ( str ) –

  C type of the tensor.

get_tensor_dtype

get_tensor_dtype(tensor: TensorT) -> np.dtype

Get the numpy dtype of a tensor.

Parameters:

• tensor

  (TensorT) –

  Tensor object.

Returns:

• dtype –

  np.dtype: Numpy dtype of the tensor.

is_constant_tensor

is_constant_tensor(tensor: TensorT, model: ModelT, subgraph: SubGraphT) -> bool

Check if a tensor is a constant tensor in the LiteRT model.

Parameters:

• tensor

  (TensorT) –

  Tensor object.

• model

  (ModelT) –

  LiteRT model object.

• subgraph

  (SubGraphT) –

  Subgraph object from LiteRT model.

Returns:

• bool ( bool ) –

  True if the tensor is constant, False otherwise.

load_tensor_data

load_tensor_data(tensor: TensorT, model: ModelT) -> np.ndarray

Load the data of a tensor from the LiteRT model.

Parameters:

• tensor

  (TensorT) –

  Tensor object.

• model

  (ModelT) –

  LiteRT model object.

Returns:

• ndarray –

  np.ndarray: Numpy array containing the tensor data.