tflite

Warning

Additional Dependencies: To use the Tensorflow Lite models, you will need to install additional dependencies. These dependencies are optional, as they can be heavy and may not be needed in all use cases. To install them, run:

pip install "audioclass[tflite]"

audioclass.models.tflite

Module for defining TensorFlow Lite-based audio classification models.

This module provides classes and functions for creating and using TensorFlow Lite models for audio classification tasks. It includes a TFLiteModel class that wraps a TensorFlow Lite interpreter and a Signature dataclass to define the model's input and output specifications.

Classes:

Name	Description
Signature	Defines the input and output signature of a TensorFlow Lite model.
TFLiteModel	A wrapper class for TensorFlow Lite audio classification models.

Functions:

Name	Description
load_model	Load a TensorFlow Lite model from a file.

Classes

Signature(input_index, classification_index, feature_index, input_length, input_dtype=np.float32) dataclass

Defines the input and output signature of a TensorFlow Lite model.

Attributes:

Name	Type	Description
classification_index	int	The index of the tensor containing classification probabilities.
feature_index	int	The index of the tensor containing extracted features.
input_dtype	DTypeLike	The data type of the input tensor. Defaults to np.float32.
input_index	int	The index of the input tensor in the model.
input_length	int	The number of audio samples expected in the input tensor.

Attributes

classification_index: int instance-attribute

The index of the tensor containing classification probabilities.

feature_index: int instance-attribute

The index of the tensor containing extracted features.

input_dtype: DTypeLike = np.float32 class-attribute instance-attribute

The data type of the input tensor. Defaults to np.float32.

input_index: int instance-attribute

The index of the input tensor in the model.

input_length: int instance-attribute

The number of audio samples expected in the input tensor.

TFLiteModel(interpreter, signature, tags, confidence_threshold, samplerate, name, logits=True, batch_size=8)

Bases: ClipClassificationModel

A wrapper class for TensorFlow Lite audio classification models.

This class provides a standardized interface for interacting with TensorFlow Lite models, allowing them to be used seamlessly with the audioclass library.

Parameters:

Name	Type	Description	Default
interpreter	Interpreter	The TensorFlow Lite interpreter object.	required
signature	Signature	The input and output signature of the model.	required
tags	List[Tag]	The list of tags that the model can predict.	required
confidence_threshold	float	The minimum confidence threshold for assigning a tag to a clip.	required
samplerate	int	The sample rate of the audio data expected by the model (in Hz).	required
name	str	The name of the model.	required
logits	bool	Whether the model outputs logits (True) or probabilities (False). Defaults to True.	True
batch_size	int	The maximum number of frames to process in each batch. Defaults to 8.	8

Methods:

Name	Description
process_array	Process a single audio array and return the model output.

Attributes:

Name	Type	Description
batch_size
confidence_threshold
input_samples
interpreter	Interpreter	The TensorFlow Lite interpreter object.
logits
name
num_classes
samplerate
signature	Signature	The input and output signature of the model.
tags

Attributes

batch_size = batch_size instance-attribute

confidence_threshold = confidence_threshold instance-attribute

input_samples = signature.input_length instance-attribute

interpreter: Interpreter = interpreter instance-attribute

The TensorFlow Lite interpreter object.

logits = logits instance-attribute

name = name instance-attribute

num_classes = len(tags) instance-attribute

samplerate = samplerate instance-attribute

signature: Signature = signature instance-attribute

The input and output signature of the model.

tags = tags instance-attribute

Functions

process_array(array)

Process a single audio array and return the model output.

Parameters:

Name	Type	Description	Default
array	ndarray	The audio array to be processed, with shape (num_frames, input_samples).	required

Returns:

Type	Description
ModelOutput	A ModelOutput object containing the class probabilities and extracted features.

Note

This is a low-level method that requires manual batching of the input audio array. If you prefer a higher-level interface that handles batching automatically, consider using process_file, process_recording, or process_clip instead.

Be aware that passing an array with a large batch size may exceed available device memory and cause the process to crash.

Functions

load_model(path, num_threads=None)

Load a TensorFlow Lite model from a file.

Parameters:

Name	Type	Description	Default
path	Union[Path, str]	The path to the TensorFlow Lite model file.	required
num_threads	Optional[int]	The number of threads to use for inference. If None, the default number of threads will be used.	None

Returns:

Type	Description
Interpreter	The TensorFlow Lite interpreter object.

process_array(interpreter, signature, array, validate_signature=False, logits=True)

Process an array with a TF Lite model.

Parameters:

Name	Type	Description	Default
interpreter	Interpreter	The TF Lite model interpreter.	required
signature	Signature	The input and output signature of the model.	required
array	ndarray	The audio array to be processed, with shape (num_frames, input_samples) or (input_samples,).	required
validate_signature	bool	Whether to validate the model signature. Defaults to False.	False
logits	bool	Whether the model outputs logits (True) or probabilities (False). Defaults to True.	True

Returns:

Type	Description
ModelOutput	A ModelOutput object containing the class probabilities and extracted features.

Raises:

Type	Description
ValueError	If the input array has the wrong shape or if the model signature is invalid.