WhisperAudioConverter

[source]

WhisperAudioConverter class

keras_hub.layers.WhisperAudioConverter(
    num_mels=80,
    num_fft_bins=400,
    stride=160,
    sampling_rate=16000,
    max_audio_length=30,
    **kwargs
)

Whisper audio converter layer.

This layer takes in a batch of audio tensors, and computes the log-mel spectrogram features for each audio tensor.

The input audio tensor can either be of shape (length_of_audio,) or (batch_size, length_of_audio). The output is a tensor of shape (batch_size, num_frames, num_mels), where num_frames is (max_audio_length * sampling_rate) / stride.

Arguments

• num_mels: int. The number of mel-frequency filters. Defaults to 80.
• num_fft_bins: int. The size of the Fourier Transform in STFT. Defaults to 400.
• stride: int. The distance between neighboring sliding window frames while computing STFT. Defaults to 160.
• sampling_rate: int. The sample rate of the audio. Defaults to 16000.
• max_audio_length: int. The length of each audio chunk in seconds. The input audio tensor will be padded/trimmed to max_audio_length * sampling_rate. Defaults to 30.

Examples

audio_tensor = tf.ones((8000,), dtype="float32")

# Compute the log-mel spectrogram.
audio_converter = keras_hub.models.WhisperAudioConverter.from_preset(
    "whisper_base_en",
)
audio_converter(audio_tensor)

# Compute the log-mel spectrogram for a batch of audio tensors.
audio_tensor_1 = tf.ones((8000,), dtype="float32")
audio_tensor_2 = tf.ones((10000,), dtype="float32")
audio_tensor = tf.ragged.stack([audio_tensor_1, audio_tensor_2], axis=0)
audio_converter(audio_tensor)

[source]

from_preset method

WhisperAudioConverter.from_preset(preset, **kwargs)

Instantiate a keras_hub.layers.AudioConverter from a model preset.

A preset is a directory of configs, weights and other file assets used to save and load a pre-trained model. The preset can be passed as one of:

1. a built-in preset identifier like 'whisper_base_en'
2. a Kaggle Models handle like 'kaggle://user/whisper/keras/whisper_base_en'
3. a Hugging Face handle like 'hf://user/whisper_base_en'
4. a path to a local preset directory like './whisper_base_en'

You can run cls.presets.keys() to list all built-in presets available on the class.

This constructor can be called in one of two ways. Either from the base class like keras_hub.models.AudioConverter.from_preset(), or from a model class like keras_hub.models.WhisperAudioConverter.from_preset(). If calling from the base class, the subclass of the returning object will be inferred from the config in the preset directory.

Arguments

• preset: string. A built-in preset identifier, a Kaggle Models handle, a Hugging Face handle, or a path to a local directory.
• load_weights: bool. If True, the weights will be loaded into the model architecture. If False, the weights will be randomly initialized.

Examples

# Load an audio converter from a preset.
converter = keras_hub.layers.AudioConverter.from_preset(
    "whisper_base_en"
)
# Convert some raw mono channel audio input.
converter(np.ones(2, 1_000))