Notes

import numpy as np
import librosa
import soundfile as sf
import os
from django.http import HttpResponse
from django.shortcuts import render
from .forms import AudioUploadForm

# Define Equalizer Bands and Their Initial Settings
equalizer_bands = {
'Bass': [20, 200, 0], # Frequency range: 20Hz - 200Hz, initial gain: 0 dB
'Midrange': [200, 2000, 0], # Frequency range: 200Hz - 2kHz, initial gain: 0 dB
'Treble': [2000, 20000, 0] # Frequency range: 2kHz - 20kHz, initial gain: 0 dB
}


# Modify Audio Based on Equalizer Settings
def apply_equalizer(audio, sample_rate, equalizer_settings):
y, sr = librosa.load(audio, sr=sample_rate)
D = librosa.stft(y)
S, phase = librosa.magphase(D)

for band, settings in equalizer_settings.items():
low_freq, high_freq, gain_db = settings
start_bin = int(low_freq / (sample_rate / 2) * len(S[0]))
end_bin = int(high_freq / (sample_rate / 2) * len(S[0]))

# Apply gain in the specified frequency range
S[start_bin:end_bin, :] *= 10**(gain_db / 20.0)

# Reconstruct the modified audio
y_modified = librosa.istft(S * phase)
return y_modified


def process_audio(request):
if request.method == 'POST':
form = AudioUploadForm(request.POST, request.FILES)
if form.is_valid():
audio_file = request.FILES['file']
mode = form.cleaned_data['mode']

# Define the file paths for original and modified audio
original_audio_path = 'media/original_audio.wav'
modified_audio_path = 'media/modified_audio.wav'

# Save the original audio to a file
with open(original_audio_path, 'wb') as destination:
for chunk in audio_file.chunks():
destination.write(chunk)

if mode == 'Equalizer':
# Apply the equalizer settings and save the modified audio
modified_audio = apply_equalizer(original_audio_path, sample_rate=44100, equalizer_settings=equalizer_bands)
sf.write(modified_audio_path, modified_audio, 44100)

# Serve the modified audio for download
with open(modified_audio_path, 'rb') as audio_file:
response = HttpResponse(audio_file.read(), content_type='audio/wav')
response['Content-Disposition'] = 'attachment; filename="modified_audio.wav"'
return response
else:
form = AudioUploadForm()
return render(request, 'upload.html', {'form': form})