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Add initial Vocoder version
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‎Vocoder.jsfx‎

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desc:Vocoder (by Geraint Luff)
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slider1:window_ms=10<1,50>-window length (ms)
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slider2:smoothing_ms=5<0,20,1>-energy smoothing (ms)
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slider3:max_gain_db=40<0,100,1>-max band gain (dB)
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slider4:switch_order=0<0,1,1{main to aux, aux to main}>-max band gain (dB)
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in_pin:main L
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in_pin:main R
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in_pin:aux L
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in_pin:aux R
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out_pin:out L
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out_pin:out R
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import ui-lib.jsfx-inc
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filename:0,themes/bitmap-simple/theme-dark-blue.png
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// https://unsplash.com/photos/jXd2FSvcRr8
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filename:1,themes/backgrounds/umberto-jXd2FSvcRr8-unsplash.png
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@init
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gfx_ext_retina = 1;
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max_gain = 100;
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function setup_stft_state(fft_size, freemem) (
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bins = fft_size/2;
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main_energy_bins = freemem;
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aux_energy_bins = freemem + bins;
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i = 0;
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loop(bins,
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main_energy[i] = 0;
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aux_energy[i] = 0;
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i += 1;
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);
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//////////////////////// Setup block
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// This is called when playback starts, or when the FFT size is changed
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0;
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////////////////////////
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);
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function process_stft_segment(fft_buffer_main, fft_buffer_aux, fft_size) local(fft_bin, left_real, left_imag, right_real, right_imag) (
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interval_ms = fft_interval*1000/srate;
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main_slew = aux_slew = 1/(smoothing_ms/interval_ms + 1);
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fft_bin = 0; // FFT bin number
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loop(fft_size/2,
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fft_bin2 = fft_bin ? (fft_size - fft_bin) : 0;
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// Unfold complex spectrum into two real spectra
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left_real = fft_buffer_main[2*fft_bin] + fft_buffer_main[2*fft_bin2];
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left_imag = fft_buffer_main[2*fft_bin + 1] - fft_buffer_main[2*fft_bin2 + 1];
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right_real = fft_buffer_main[2*fft_bin + 1] + fft_buffer_main[2*fft_bin2 + 1];
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right_imag = -fft_buffer_main[2*fft_bin] + fft_buffer_main[2*fft_bin2];
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aux_left_real = fft_buffer_aux[2*fft_bin] + fft_buffer_aux[2*fft_bin2];
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aux_left_imag = fft_buffer_aux[2*fft_bin + 1] - fft_buffer_aux[2*fft_bin2 + 1];
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aux_right_real = fft_buffer_aux[2*fft_bin + 1] + fft_buffer_aux[2*fft_bin2 + 1];
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aux_right_imag = -fft_buffer_aux[2*fft_bin] + fft_buffer_aux[2*fft_bin2];
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//////////////////////// Main STFT block
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input_energy = left_real*left_real + left_imag*left_imag + right_real*right_real + right_imag*right_imag;
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aux_energy = aux_left_real*aux_left_real + aux_left_imag*aux_left_imag + aux_right_real*aux_right_real + aux_right_imag*aux_right_imag;
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main_energy_bins[fft_bin] += (input_energy - main_energy_bins[fft_bin])*main_slew;
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input_energy = main_energy_bins[fft_bin];
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aux_energy_bins[fft_bin] += (aux_energy - aux_energy_bins[fft_bin])*aux_slew;
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aux_energy = aux_energy_bins[fft_bin];
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energy_ratio = aux_energy/(aux_energy/max_gain + input_energy + 0.000001);
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gain = sqrt(energy_ratio);
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left_real *= gain;
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left_imag *= gain;
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right_real *= gain;
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right_imag *= gain;
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////////////////////////
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// Re-fold back into complex spectrum
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fft_buffer_main[2*fft_bin] = (left_real - right_imag)*0.5;
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fft_buffer_main[2*fft_bin + 1] = (left_imag + right_real)*0.5;
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fft_buffer_main[2*fft_bin2] = (left_real + right_imag)*0.5;
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fft_buffer_main[2*fft_bin2 + 1] = (-left_imag + right_real)*0.5;
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fft_bin += 1;
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);
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);
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MAX_FFT_SIZE = 32768;
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freemem = 0;
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freemem = ui_setup(freemem);
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freemem = (fft_buffer = freemem) + MAX_FFT_SIZE*2;
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freemem = (fft_buffer2 = freemem) + MAX_FFT_SIZE*2;
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freemem = (window_buffer = freemem) + MAX_FFT_SIZE;
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buffer_length = MAX_FFT_SIZE;
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buffer_index = 0;
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freemem = (input_buffer = freemem) + buffer_length*2;
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freemem = (aux_buffer = freemem) + buffer_length*2;
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freemem = (output_buffer = freemem) + buffer_length*2;
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function window(r) local(s, s2, gaussian_width, x) (
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// When squared, the Hann window adds up perfectly for overlap >= 4, so it's suitable for perfect reconstruction
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(0.5 - 0.5*cos(r*2*$pi))/sqrt(0.375);
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);
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fft_size = 0;
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@block
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max_gain = pow(10, max_gain_db*0.05);
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overlap_factor = 6;
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window_samples = min(ceil(window_ms*0.001*srate), MAX_FFT_SIZE);
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fft_size = 16;
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while (fft_size < window_samples) (
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fft_size *= 2;
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);
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fft_interval = ceil(window_samples/overlap_factor);
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window_samples = fft_size - 3;
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fft_scaling_factor = 1/window_samples*(fft_interval/fft_size);
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window_samples != prev_window_samples ? (
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prev_window_samples = window_samples;
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// Fill window buffer
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i = 0;
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while (i < window_samples) (
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r = (i + 0.5)/window_samples;
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window_buffer[i] = window(r);
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i += 1;
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);
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while (i < fft_size) (
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window_buffer[i] = 0;
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);
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);
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fft_size != prev_fft_size ? (
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setup_stft_state(fft_size, freemem);
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prev_fft_size = fft_size;
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);
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pdc_delay = window_samples;
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pdc_bot_ch = 0;
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pdc_top_ch = 2;
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@sample
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input_buffer[buffer_index*2] = spl0;
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input_buffer[buffer_index*2 + 1] = spl1;
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aux_buffer[buffer_index*2] = spl2;
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aux_buffer[buffer_index*2 + 1] = spl3;
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fft_counter += 1;
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fft_counter >= fft_interval ? (
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fft_counter = 0;
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// Copy input to buffer
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bi = buffer_index - window_samples;
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i = 0;
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loop(window_samples,
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i2 = bi + i;
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i2 < 0 ? i2 += buffer_length;
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// main
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fft_buffer[2*i] = input_buffer[2*i2]*window_buffer[i];
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fft_buffer[2*i + 1] = input_buffer[2*i2 + 1]*window_buffer[i];
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// aux
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fft_buffer2[2*i] = aux_buffer[2*i2]*window_buffer[i];
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fft_buffer2[2*i + 1] = aux_buffer[2*i2 + 1]*window_buffer[i];
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i += 1;
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);
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loop(fft_size - window_samples,
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fft_buffer[2*i] = 0;
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fft_buffer[2*i + 1] = 0;
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fft_buffer2[2*i] = 0;
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fft_buffer2[2*i + 1] = 0;
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i += 1;
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);
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// Process buffer
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fft(fft_buffer, fft_size);
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fft_permute(fft_buffer, fft_size);
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fft(fft_buffer2, fft_size);
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fft_permute(fft_buffer2, fft_size);
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switch_order ? (
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out_fft_buffer = fft_buffer2;
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process_stft_segment(fft_buffer2, fft_buffer, fft_size);
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) : (
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out_fft_buffer = fft_buffer;
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process_stft_segment(fft_buffer, fft_buffer2, fft_size);
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);
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fft_ipermute(out_fft_buffer, fft_size);
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ifft(out_fft_buffer, fft_size);
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// Add to output
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i = 0;
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loop(window_samples,
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i2 = buffer_index + i;
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(i2 >= buffer_length) ? i2 -= buffer_length;
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output_buffer[2*i2] += out_fft_buffer[2*i]*fft_scaling_factor*window_buffer[i];
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output_buffer[2*i2 + 1] += out_fft_buffer[2*i + 1]*fft_scaling_factor*window_buffer[i];
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i += 1;
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);
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);
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output_index = buffer_index;
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spl0 = output_buffer[output_index*2];
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spl1 = output_buffer[output_index*2 + 1];
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output_buffer[output_index*2] = 0; // clear the sample we just read
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output_buffer[output_index*2 + 1] = 0;
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buffer_index = (buffer_index + 1)%buffer_length;
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@gfx 420 150
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function labelled_dial(value, low, high, bias, default, label, format) (
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ui_push_height(50);
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value = control_dial(value, low, high, bias, default);
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ui_pop();
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ui_push_above(50);
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ui_text(label);
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ui_pop();
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ui_push_below(50);
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ui_textnumber(value, format);
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ui_pop();
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value;
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);
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function labelled_switch(value, label, valueText) (
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ui_push_height(35);
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ui_push_width(60);
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value = control_switch(value);
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ui_pop();
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ui_pop();
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ui_push_above(50);
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ui_text(label);
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ui_pop();
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ui_push_below(50);
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ui_text(valueText);
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ui_pop();
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value;
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);
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control_start("main", "bitmap-simple", 0);
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gfx_a = 0.8;
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g_scale = max(gfx_w/450, gfx_h/300);
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gfx_x = (gfx_w - 450*g_scale)*0.5;
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gfx_y = (gfx_h - 300*g_scale)*0.5;
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gfx_mode = 2;
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gfx_blit(1, g_scale, 0);
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gfx_mode = 0;
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ui_screen() == "main" ? (
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ui_split_leftratio(1/4);
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ui_automate(window_ms, labelled_dial(window_ms, 1, 50, 2, 10, "window", "%i ms"));
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ui_split_next();
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ui_automate(smoothing_ms, labelled_dial(smoothing_ms, 0, 20, 2, 5, "smoothing", "%i ms"));
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ui_split_next();
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ui_automate(max_gain_db, labelled_dial(max_gain_db, 0, 100, 2, 40, "max gain", "%i dB"));
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ui_split_next();
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ui_automate(switch_order, labelled_switch(switch_order, "swap inputs", switch_order ? "on" : "off"));
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ui_pop();
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) : control_system();

‎index.html‎

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@@ -215,6 +215,9 @@ <h1>Effects</h1>
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[*][url=https://geraintluff.github.io/jsfx#MIDI%20Gate]MIDI Gate[/url] - a velocity-sensitive MIDI-controlled gate. Audio passes through only when MIDI note is down (or up, in &quot;mute&quot; mode).
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[*][url=https://geraintluff.github.io/jsfx#MIDI%20Harmony]MIDI Harmony[/url] - arpeggiator and auto-accompaniment plugin[/list]
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[b]Misc[/b]
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[list][*][url=https://geraintluff.github.io/jsfx#Vocoder]Vocoder[/url] - Misc effect[/list]
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[b]Pitch Correction[/b]
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[list][*][url=https://geraintluff.github.io/jsfx#Warble]Warble[/url] - a basic pitch-editing effect[/list]
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@@ -260,6 +263,7 @@ <h3>MIDI</h3><ul><li><a href="#Droplets">Droplets</a> - randomly play the notes
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</li>
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<li><a href="#MIDI Harmony">MIDI Harmony</a> - arpeggiator and auto-accompaniment plugin
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</li></ul>
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<h3>Misc</h3><ul><li><a href="#Vocoder">Vocoder</a> - Misc effect</li></ul>
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<h3>Pitch Correction</h3><ul><li><a href="#Warble">Warble</a> - a basic pitch-editing effect
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</li></ul></div>
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<!--/reapack:nav-->
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<p>The &quot;Lookahead&quot; dial controls how much latency is added. With this at 0, sometimes the start of a note can sometimes be momentarily detuned because of ongoing vibrato. To prevent this completely, turn the dial to its maximum value (which scales according to the LFO Rate value).</p>
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<p><em>(background by Tom Barrett on <a href="https://unsplash.com/photos/-bSucp2nUdQ">Unsplash</a>)</em></p>
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</div>
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<div class="reapack-package" id="Vocoder"><h1>Vocoder</h1></div>
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<div class="reapack-package reapack-package-with-links" id="Warble"><div class="reapack-links"><audio controls preload="none" src="audio-demos/warble-formant-mod.mp3"></audio><audio controls preload="none" src="audio-demos/warble-original.mp3"></audio><audio controls preload="none" src="audio-demos/warble-shifted.mp3"></audio><audio controls preload="none" src="audio-demos/warble-subtle.mp3"></audio></div><h1 id="warble">Warble</h1>
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<p>Warble is a relatively basic pitch-editing plugin. It analyses incoming audio, stores and displays it on a zoomable graph (middle mouse and scroll wheel). (demo: <a href="audio-demos/warble-original.mp3">original</a>, <a href="audio-demos/warble-subtle.mp3">minor correction</a>, <a href="audio-demos/warble-shifted.mp3">major alterations</a>, <a href="audio-demos/warble-formant-mod.mp3">formant LFO</a>)</p>
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<p>There are three tools: nudge, erase and smooth. You use these tools with the mouse (left/right buttons do different things) to define how much it should be shifted. The current change amount is displayed in red.</p>

‎index.xml‎

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<metadata>
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</metadata>
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</reapack>
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<reapack name="Vocoder" type="effect">
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<metadata>
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</metadata>
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</reapack>
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</category>
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</index>

‎reapack.json‎

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}
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},
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"version": "1.3.4"
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},
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"Vocoder": {
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"type": "effect",
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"category": "Misc",
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"files": {
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"Vocoder.jsfx": {
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"main": false
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},
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"themes/bitmap-simple/theme-dark-blue.png": {
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"main": false
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},
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"themes/backgrounds/umberto-jXd2FSvcRr8-unsplash.png": {
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"main": false
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}
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}
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}
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},
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"url": "https://geraintluff.github.io/jsfx",

‎themes/backgrounds/umberto-jXd2FSvcRr8-unsplash.png‎

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