| import numpy as np |
| import librosa |
|
|
|
|
| def process_audio(audio, sr=16000, silence_thresh=-60, min_silence_len=250): |
| """ |
| Splits an audio signal into segments using a fixed frame size and hop size. |
| |
| Parameters: |
| - audio (np.ndarray): The audio signal to split. |
| - sr (int): The sample rate of the input audio (default is 16000). |
| - silence_thresh (int): Silence threshold (default =-60dB) |
| - min_silence_len (int): Minimum silence duration (default 250ms). |
| |
| Returns: |
| - list of np.ndarray: A list of audio segments. |
| - np.ndarray: The intervals where the audio was split. |
| """ |
| frame_length = int(min_silence_len / 1000 * sr) |
| hop_length = frame_length // 2 |
| intervals = librosa.effects.split( |
| audio, top_db=-silence_thresh, frame_length=frame_length, hop_length=hop_length |
| ) |
| audio_segments = [audio[start:end] for start, end in intervals] |
|
|
| return audio_segments, intervals |
|
|
|
|
| def merge_audio(audio_segments, intervals, sr_orig, sr_new): |
| """ |
| Merges audio segments back into a single audio signal, filling gaps with silence. |
| |
| Parameters: |
| - audio_segments (list of np.ndarray): The non-silent audio segments. |
| - intervals (np.ndarray): The intervals used for splitting the original audio. |
| - sr_orig (int): The sample rate of the original audio |
| - sr_new (int): The sample rate of the model |
| |
| Returns: |
| - np.ndarray: The merged audio signal with silent gaps restored. |
| """ |
| sr_ratio = sr_new / sr_orig if sr_new > sr_orig else 1.0 |
|
|
| merged_audio = np.zeros( |
| int(intervals[0][0] * sr_ratio if intervals[0][0] > 0 else 0), |
| dtype=audio_segments[0].dtype, |
| ) |
|
|
| merged_audio = np.concatenate((merged_audio, audio_segments[0])) |
|
|
| for i in range(1, len(intervals)): |
| silence_duration = int((intervals[i][0] - intervals[i - 1][1]) * sr_ratio) |
| silence = np.zeros(silence_duration, dtype=audio_segments[0].dtype) |
| merged_audio = np.concatenate((merged_audio, silence, audio_segments[i])) |
|
|
| return merged_audio |
|
|
