tflite 🔗

def tflite_model_delete(self, resource: Resource) -> None:
    """Performs the Tensorflow Lite model deletion operation.

    Wraps the `vaccel_tflite_session_delete()` C operation.

    Args:
        resource: A resource with the model to unload.

    Returns:
        The status of the operation execution.

    Raises:
        RuntimeError: If the `Session` is uninitialized.
        FFIError: If the C operation fails.
    """
    if not self._c_ptr:
        msg = "Uninitialized session"
        raise RuntimeError(msg)

    ret = lib.vaccel_tflite_session_delete(self._c_ptr, resource._c_ptr)
    if ret != 0:
        raise FFIError(ret, "Tensorflow Lite model delete failed")

def tflite_model_load(self, resource: Resource) -> None:
    """Performs the Tensorflow Lite model loading operation.

    Wraps the `vaccel_tflite_session_load()` C operation.

    Args:
        resource: A resource with the model to load.

    Raises:
        RuntimeError: If the `Session` is uninitialized.
        FFIError: If the C operation fails.
    """
    if not self._c_ptr:
        msg = "Uninitialized session"
        raise RuntimeError(msg)

    ret = lib.vaccel_tflite_session_load(self._c_ptr, resource._c_ptr)
    if ret != 0:
        raise FFIError(ret, "Tensorflow Lite model loading failed")

def tflite_model_run(
    self,
    resource: Resource,
    in_tensors: list[Tensor],
    nr_out_tensors: int = 1,
) -> (list[Tensor], int):
    """Performs the Tensorflow Lite model run operation.

    Wraps the `vaccel_tflite_session_run()` C operation.

    Args:
        resource: A resource with the model to run.
        in_tensors: The input tensors for the inference.
        nr_out_tensors: The number of output tensors. Defaults to 1.

    Returns:
        A tuple containing:
            - The output tensors
            - The status of the operation execution.

    Raises:
        RuntimeError: If the `Session` is uninitialized.
        FFIError: If the C operation fails.
    """
    if not self._c_ptr:
        msg = "Uninitialized session"
        raise RuntimeError(msg)

    c_in_tensors = CList.from_ptrs(in_tensors)
    c_out_tensors = CList.from_ptrs([Tensor.empty()] * nr_out_tensors)
    status = CInt(0, "uint8_t")

    ret = lib.vaccel_tflite_session_run(
        self._c_ptr,
        resource._c_ptr,
        c_in_tensors._c_ptr,
        len(c_in_tensors),
        c_out_tensors._c_ptr,
        len(c_out_tensors),
        status._c_ptr,
    )
    if ret != 0:
        raise FFIError(ret, "Tensorflow Lite model run failed")

    out_tensors = [Tensor.from_c_obj(t) for t in c_out_tensors.value]
    return (out_tensors, status.value)

@classmethod
def empty(cls) -> "Tensor":
    """Initializes a new empty `Tensor` object.

    The object a NULL pointer in place of the C struct.

    Returns:
        A new `Tensor` object
    """
    inst = cls.__new__(cls)
    inst._c_obj_ptr = ffi.new("struct vaccel_tflite_tensor **")
    inst._c_obj = inst._c_obj_ptr[0]
    inst._c_obj_ptr[0] = ffi.NULL
    inst._c_size = ffi.sizeof("struct vaccel_tflite_tensor *")
    return inst

@classmethod
def from_c_obj(cls, c_obj: ffi.CData) -> "Tensor":
    """Initializes a new `Tensor` object from an existing C struct.

    Args:
        c_obj: A pointer to a `struct vaccel_tflite_tensor` C object.

    Returns:
        A new `Tensor` object
    """
    type_str = ffi.getctype(ffi.typeof(c_obj))
    if type_str != "struct vaccel_tflite_tensor *":
        msg = f"Expected 'struct vaccel_tflite_tensor *', got '{type_str}'"
        raise TypeError(msg)

    inst = cls.__new__(cls)
    inst._c_obj = c_obj
    inst._c_size = ffi.sizeof(inst._c_obj)
    inst._dims = None
    inst._data = None
    inst._data_type = None
    inst._c_obj_ptr = None
    return inst