AH_SIntPtr irmeasure_calc_sweep_mem_size(t_ess *sweep_params, long num_out_chans, double out_length, double sample_rate)
{
    AH_SIntPtr gen_length = ess_get_length(sweep_params);
    AH_SIntPtr rec_length = (AH_SIntPtr) (num_out_chans * ((out_length * sample_rate) + gen_length));

    return rec_length * sizeof(double);
}
void irmeasure_process(t_irmeasure *x, t_symbol *sym, short argc, t_atom *argv)
{
    FFT_SETUP_D fft_setup;

    FFT_SPLIT_COMPLEX_D spectrum_1;
    FFT_SPLIT_COMPLEX_D spectrum_2;
    FFT_SPLIT_COMPLEX_D spectrum_3;

    void *measurement_rec;
    void *rec_mem;
    double *excitation_sig;
    double *out_buf;
    double *out_mem;
    float *filter_in;

    t_symbol *filter = filter_retriever(x->deconvolve_filter_specifier);

    double filter_specifier[HIRT_MAX_SPECIFIER_ITEMS];
    double range_specifier[HIRT_MAX_SPECIFIER_ITEMS];

    double test_pow;
    double max_pow;
    double sample_rate = x->sample_rate;
    double deconvolve_phase = phase_retriever(x->deconvolve_phase);

    long deconvolve_mode = x->deconvolve_mode;
    long bandlimit = x->measure_mode == SWEEP ? x->bandlimit : 0;

    AH_SIntPtr rec_length = x->T2;
    AH_SIntPtr gen_length = 0;
    AH_SIntPtr filter_length = buffer_length(filter);

    AH_UIntPtr fft_size;
    AH_UIntPtr fft_size_log2;
    AH_UIntPtr mem_size;
    AH_UIntPtr i;

    t_ess sweep_params;
    t_mls max_length_params;
    t_noise_params noise_params;

    switch (x->measure_mode)
    {
        case SWEEP:
            ess_params(&sweep_params, x->sweep_params.rf1, x->sweep_params.rf2, x->sweep_params.fade_in, x->sweep_params.fade_out, x->sweep_params.RT, x->sweep_params.sample_rate, x->inv_amp ? x->sweep_params.amp : 1, x->amp_curve);
            gen_length = ess_get_length(&sweep_params);
            break;

        case MLS:

            mls_params(&max_length_params, x->max_length_params.order, x->inv_amp ? x->max_length_params.amp : 1);
            gen_length = mls_get_length(&max_length_params);

            break;

        case NOISE:

            coloured_noise_params(&noise_params, x->noise_params.mode, x->noise_params.fade_in, x->noise_params.fade_out, x->noise_params.RT, x->noise_params.sample_rate,   x->inv_amp ? x->noise_params.amp : 1);
            gen_length = coloured_noise_get_length(&noise_params);
            break;
    }

    // Check and calculate lengths

    fft_size = calculate_fft_size(rec_length + gen_length, &fft_size_log2);

    // Allocate Temporary Memory

    fft_setup = hisstools_create_setup_d(fft_size_log2);

    excitation_sig = (double *)  malloc(gen_length * sizeof(double));

    spectrum_1.realp = ALIGNED_MALLOC((sizeof(double) * fft_size * 4));
    spectrum_1.imagp = spectrum_1.realp + (fft_size >> 1);
    spectrum_2.realp = spectrum_1.imagp + (fft_size >> 1);
    spectrum_2.imagp = spectrum_2.realp + (fft_size >> 1);
    spectrum_3.realp = spectrum_2.imagp + (fft_size >> 1);
    spectrum_3.imagp = spectrum_3.realp + fft_size;

    filter_in = filter_length ? (float *) ALIGNED_MALLOC(sizeof(float) * filter_length) : 0;

    if (!fft_setup || !excitation_sig || !spectrum_1.realp || (filter_length && !filter_in))
    {
        object_error ((t_object *) x, "could not allocate temporary memory for processing");

        hisstools_destroy_setup_d(fft_setup);
        free(excitation_sig);
        ALIGNED_FREE(spectrum_1.realp);
        ALIGNED_FREE(filter_in);

        return;
    }

    // Allocate output memory and get record memory

    rec_mem = access_mem_swap(&x->rec_mem, &mem_size);
    out_mem = grow_mem_swap(&x->out_mem, fft_size * x->current_num_active_ins * sizeof(double), fft_size * x->current_num_active_ins);

    if (!out_mem)
    {
        object_error ((t_object *) x, "could not allocate memory for output storage");
        free(excitation_sig);
        hisstools_destroy_setup_d(fft_setup);
        return;
    }

    // Generate Signal

    switch (x->measure_mode)
    {
        case SWEEP:
            ess_gen(&sweep_params, excitation_sig, true);
            break;

        case MLS:
            mls_gen(&max_length_params, excitation_sig, true);
            break;

        case NOISE:
            coloured_noise_gen(&noise_params, excitation_sig, true);
            break;
    }

    // Transform excitation signal into complex spectrum 2

    time_to_halfspectrum_double(fft_setup, excitation_sig, gen_length, spectrum_2, fft_size);

    if (bandlimit)
    {
        // Calculate standard filter for bandlimited deconvolution (sweep * inv sweep)

        ess_igen(&sweep_params, excitation_sig, INVERT_ALL, true);
        time_to_halfspectrum_double(fft_setup, excitation_sig, gen_length, spectrum_3, fft_size);
        convolve(spectrum_3, spectrum_2, fft_size, SPECTRUM_REAL);

        // Calculate full power spectrum from half spectrum - convert filter to have the required phase

        power_full_spectrum_from_half_spectrum(spectrum_3, fft_size);
        variable_phase_from_power_spectrum(fft_setup, spectrum_3, fft_size, deconvolve_phase, true);

        // Convert back to real format

        spectrum_3.imagp[0] = spectrum_3.realp[fft_size >> 1];
    }
    else
    {
        // Find maximum power to scale

        for (i = 1, max_pow = 0; i < (fft_size >> 1); i++)
void irextract_process (t_irextract *x, t_symbol *rec_buffer, t_atom_long num_channels, double sample_rate)
{
	FFT_SETUP_D fft_setup;
	
	FFT_SPLIT_COMPLEX_D spectrum_1;
	FFT_SPLIT_COMPLEX_D spectrum_2;
	FFT_SPLIT_COMPLEX_D spectrum_3;

	void *excitation_sig;
	double *out_mem;
	float *rec_mem;
	float *filter_in;
	
	t_symbol *filter = filter_retriever(x->deconvolve_filter_specifier);
	
	double filter_specifier[HIRT_MAX_SPECIFIER_ITEMS];
	double range_specifier[HIRT_MAX_SPECIFIER_ITEMS];
	
	double test_pow;
	double max_pow;
	double deconvolve_phase = phase_retriever(x->deconvolve_phase);
	
	long deconvolve_mode = x->deconvolve_mode;
	long bandlimit = x->measure_mode == SWEEP ? x->bandlimit : 0;
	
	AH_SIntPtr rec_length = buffer_length(rec_buffer);
	AH_SIntPtr gen_length = 0;
	AH_SIntPtr filter_length = buffer_length(filter);
	AH_SIntPtr out_length_samps;
	
	AH_UIntPtr fft_size; 
	AH_UIntPtr fft_size_log2;
	AH_UIntPtr i;
	
	if (buffer_check((t_object *)x, rec_buffer) || !rec_length)
		return;
	
	switch (x->measure_mode)
	{	
		case SWEEP:
			gen_length = ess_get_length(&x->sweep_params);
			break;
			
		case MLS:
			gen_length = mls_get_length(&x->max_length_params);
			break;
			
		case NOISE:
			gen_length = coloured_noise_get_length(&x->noise_params);
			break;
	}
	
	// Check and calculate lengths
	
	fft_size = calculate_fft_size(rec_length + gen_length, &fft_size_log2);
	
	if (rec_length % num_channels)
		object_warn ((t_object *) x, "buffer length is not a multiple of the number of channels - number may be wrong");
		
	if (((rec_length / num_channels) - gen_length) < 1)
	{
		object_error ((t_object *) x, "buffer is not long enough for generated signal");
		return;
	}
	
	out_length_samps = ((rec_length / num_channels) - gen_length);
	
	if (x->out_length)
	{
		if (out_length_samps < (x->out_length * sample_rate))
			object_warn ((t_object *) x, "buffer is not long enough for requested output length");
		else
			out_length_samps = (AH_SIntPtr) (x->out_length * sample_rate);
	}
	
	// Allocate Temporary Memory
	
	fft_setup = hisstools_create_setup_d(fft_size_log2);
		
	excitation_sig = malloc(((gen_length > filter_length) ? gen_length : filter_length) * sizeof(double));
	
	spectrum_1.realp = ALIGNED_MALLOC((sizeof(double) * fft_size * 4));
	spectrum_1.imagp = spectrum_1.realp + (fft_size >> 1);
	spectrum_2.realp = spectrum_1.imagp + (fft_size >> 1);
	spectrum_2.imagp = spectrum_2.realp + (fft_size >> 1);
	spectrum_3.realp = spectrum_2.imagp + (fft_size >> 1);
	spectrum_3.imagp = spectrum_3.realp + fft_size;
		
	rec_mem = (float *) malloc(rec_length * sizeof(float));
	
	filter_in = filter_length ? ALIGNED_MALLOC(sizeof(float *) * filter_length) : 0; 
	
	if (!fft_setup || !excitation_sig || !spectrum_1.realp || (filter_length && !filter_in))
	{
		object_error ((t_object *) x, "could not allocate temporary memory for processing");
		
		hisstools_destroy_setup_d(fft_setup);
		free(excitation_sig);
		ALIGNED_FREE(spectrum_1.realp);
		ALIGNED_FREE(filter_in);
	
		return;
	}
	
	x->fft_size = fft_size;
	x->sample_rate = sample_rate;
	x->out_length_samps = out_length_samps;
	x->gen_length = gen_length;
	
	// Allocate output memory and get record memory
	
	out_mem = grow_mem_swap(&x->out_mem, fft_size * sizeof(double), fft_size);
	
	if (!out_mem) 
	{
		object_error ((t_object *) x, "could not allocate memory for output storage");
		free(excitation_sig);
		hisstools_destroy_setup_d(fft_setup);
		return;
	}

	// Generate Signal
	
	switch (x->measure_mode)
	{
		case SWEEP:
			ess_gen(&x->sweep_params, excitation_sig, true);
			break;
			
		case MLS:
			mls_gen(&x->max_length_params, excitation_sig, true);
			break;
			
		case NOISE:
			coloured_noise_gen(&x->noise_params, excitation_sig, true);
			break;
	}
	
	// Transform excitation signal into complex spectrum 2
	
	time_to_halfspectrum_double(fft_setup, excitation_sig, gen_length, spectrum_2, fft_size);
			 
	if (bandlimit)
	{
		// Calculate standard filter for bandlimited deconvolution (sweep * inv sweep)
		
		ess_igen(&x->sweep_params, excitation_sig, true, true);
		time_to_halfspectrum_double(fft_setup, excitation_sig, gen_length, spectrum_3, fft_size);
		convolve(spectrum_3, spectrum_2, fft_size, SPECTRUM_REAL);
							
		// Calculate full power spectrum from half spectrum - convert filter to have the required phase
		
		power_full_spectrum_from_half_spectrum(spectrum_3, fft_size);		
		variable_phase_from_power_spectrum(fft_setup, spectrum_3, fft_size, deconvolve_phase, true);	
		
		// Convert back to real format
		
		spectrum_3.imagp[0] = spectrum_3.realp[fft_size >> 1];		
	}
	else 
	{
		// Find maximum power to scale 
		
		for (i = 1, max_pow = 0; i < (fft_size >> 1); i++)