mirror of
https://github.com/holub/mame
synced 2025-06-15 08:57:05 +03:00
Removed specific filter implementation and merged it with placed where used (nw)
This commit is contained in:
Miodrag Milanovic
parent
583eaef9f0
commit
97a195ef03
@ -205,8 +205,6 @@ files {
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MAME_DIR .. "src/emu/debug/express.h",
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MAME_DIR .. "src/emu/debug/express.h",
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MAME_DIR .. "src/emu/debug/textbuf.cpp",
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MAME_DIR .. "src/emu/debug/textbuf.cpp",
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MAME_DIR .. "src/emu/debug/textbuf.h",
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MAME_DIR .. "src/emu/debug/textbuf.h",
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MAME_DIR .. "src/emu/sound/filter.cpp",
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MAME_DIR .. "src/emu/sound/filter.h",
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MAME_DIR .. "src/emu/sound/wavwrite.cpp",
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MAME_DIR .. "src/emu/sound/wavwrite.cpp",
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MAME_DIR .. "src/emu/sound/wavwrite.h",
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MAME_DIR .. "src/emu/sound/wavwrite.h",
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MAME_DIR .. "src/emu/drivers/empty.cpp",
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MAME_DIR .. "src/emu/drivers/empty.cpp",
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@ -1,234 +0,0 @@
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// license:BSD-3-Clause
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// copyright-holders:Derrick Renaud, Couriersud
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#include "emu.h"
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#include "filter.h"
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static filter* filter_alloc(void) {
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auto f = global_alloc(filter);
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return f;
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}
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void filter_free(filter* f) {
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global_free(f);
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}
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void filter_state_reset(filter* f, filter_state* s) {
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int i;
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s->prev_mac = 0;
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for(i=0;i<f->order;++i) {
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s->xprev[i] = 0;
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}
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}
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filter_state* filter_state_alloc(void) {
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int i;
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auto s = global_alloc(filter_state);
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s->prev_mac = 0;
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for(i=0;i<FILTER_ORDER_MAX;++i)
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s->xprev[i] = 0;
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return s;
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}
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void filter_state_free(filter_state* s) {
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global_free(s);
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}
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/****************************************************************************/
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/* FIR */
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filter_real filter_compute(filter* f, filter_state* s) {
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unsigned order = f->order;
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unsigned midorder = f->order / 2;
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filter_real y = 0;
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unsigned i,j,k;
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/* i == [0] */
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/* j == [-2*midorder] */
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i = s->prev_mac;
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j = i + 1;
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if (j == order)
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j = 0;
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/* x */
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for(k=0;k<midorder;++k) {
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y += f->xcoeffs[midorder-k] * (s->xprev[i] + s->xprev[j]);
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++j;
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if (j == order)
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j = 0;
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if (i == 0)
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i = order - 1;
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else
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--i;
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}
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y += f->xcoeffs[0] * s->xprev[i];
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#ifdef FILTER_USE_INT
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return y >> FILTER_INT_FRACT;
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#else
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return y;
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#endif
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}
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filter* filter_lp_fir_alloc(double freq, int order) {
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filter* f = filter_alloc();
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unsigned midorder = (order - 1) / 2;
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unsigned i;
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double gain;
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assert( order <= FILTER_ORDER_MAX );
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assert( order % 2 == 1 );
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assert( 0 < freq && freq <= 0.5 );
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/* Compute the antitrasform of the perfect low pass filter */
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gain = 2*freq;
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#ifdef FILTER_USE_INT
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f->xcoeffs[0] = gain * (1 << FILTER_INT_FRACT);
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#else
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f->xcoeffs[0] = gain;
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#endif
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for(i=1;i<=midorder;++i) {
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/* number of the sample starting from 0 to (order-1) included */
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unsigned n = i + midorder;
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/* sample value */
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double c = sin(2*M_PI*freq*i) / (M_PI*i);
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/* apply only one window or none */
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/* double w = 2 - 2*n/(order-1); */ /* Bartlett (triangular) */
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/* double w = 0.5 * (1 - cos(2*M_PI*n/(order-1))); */ /* Hanning */
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double w = 0.54 - 0.46 * cos(2*M_PI*n/(order-1)); /* Hamming */
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/* double w = 0.42 - 0.5 * cos(2*M_PI*n/(order-1)) + 0.08 * cos(4*M_PI*n/(order-1)); */ /* Blackman */
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/* apply the window */
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c *= w;
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/* update the gain */
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gain += 2*c;
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/* insert the coeff */
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#ifdef FILTER_USE_INT
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f->xcoeffs[i] = c * (1 << FILTER_INT_FRACT);
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#else
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f->xcoeffs[i] = c;
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#endif
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}
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/* adjust the gain to be exact 1.0 */
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for(i=0;i<=midorder;++i) {
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#ifdef FILTER_USE_INT
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f->xcoeffs[i] /= gain;
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#else
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f->xcoeffs[i] = f->xcoeffs[i] * (double)(1 << FILTER_INT_FRAC) / gain;
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#endif
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}
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/* decrease the order if the last coeffs are 0 */
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i = midorder;
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while (i > 0 && f->xcoeffs[i] == 0.0)
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--i;
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f->order = i * 2 + 1;
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return f;
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}
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void filter2_setup(device_t *device, int type, double fc, double d, double gain,
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filter2_context *filter2)
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{
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int sample_rate = device->machine().sample_rate();
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double w; /* cutoff freq, in radians/sec */
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double w_squared;
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double den; /* temp variable */
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double two_over_T = 2*sample_rate;
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double two_over_T_squared = two_over_T * two_over_T;
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/* calculate digital filter coefficents */
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/*w = 2.0*M_PI*fc; no pre-warping */
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w = sample_rate*2.0*tan(M_PI*fc/sample_rate); /* pre-warping */
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w_squared = w*w;
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den = two_over_T_squared + d*w*two_over_T + w_squared;
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filter2->a1 = 2.0*(-two_over_T_squared + w_squared)/den;
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filter2->a2 = (two_over_T_squared - d*w*two_over_T + w_squared)/den;
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switch (type)
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{
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case FILTER_LOWPASS:
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filter2->b0 = filter2->b2 = w_squared/den;
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filter2->b1 = 2.0*(filter2->b0);
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break;
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case FILTER_BANDPASS:
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filter2->b0 = d*w*two_over_T/den;
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filter2->b1 = 0.0;
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filter2->b2 = -(filter2->b0);
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break;
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case FILTER_HIGHPASS:
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filter2->b0 = filter2->b2 = two_over_T_squared/den;
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filter2->b1 = -2.0*(filter2->b0);
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break;
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default:
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device->logerror("filter2_setup() - Invalid filter type for 2nd order filter.");
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break;
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}
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filter2->b0 *= gain;
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filter2->b1 *= gain;
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filter2->b2 *= gain;
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}
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/* Reset the input/output voltages to 0. */
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void filter2_reset(filter2_context *filter2)
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{
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filter2->x0 = 0;
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filter2->x1 = 0;
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filter2->x2 = 0;
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filter2->y0 = 0;
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filter2->y1 = 0;
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filter2->y2 = 0;
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}
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/* Step the filter. */
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void filter2_step(filter2_context *filter2)
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{
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filter2->y0 = -filter2->a1 * filter2->y1 - filter2->a2 * filter2->y2 +
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filter2->b0 * filter2->x0 + filter2->b1 * filter2->x1 + filter2->b2 * filter2->x2;
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filter2->x2 = filter2->x1;
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filter2->x1 = filter2->x0;
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filter2->y2 = filter2->y1;
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filter2->y1 = filter2->y0;
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}
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/* Setup a filter2 structure based on an op-amp multipole bandpass circuit. */
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void filter_opamp_m_bandpass_setup(device_t *device, double r1, double r2, double r3, double c1, double c2,
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filter2_context *filter2)
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{
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double r_in, fc, d, gain;
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if (r1 == 0)
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{
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device->logerror("filter_opamp_m_bandpass_setup() - r1 can not be 0");
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return; /* Filter can not be setup. Undefined results. */
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}
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if (r2 == 0)
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{
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gain = 1;
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r_in = r1;
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}
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else
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{
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gain = r2 / (r1 + r2);
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r_in = 1.0 / (1.0/r1 + 1.0/r2);
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}
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fc = 1.0 / (2 * M_PI * sqrt(r_in * r3 * c1 * c2));
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d = (c1 + c2) / sqrt(r3 / r_in * c1 * c2);
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gain *= -r3 / r_in * c2 / (c1 + c2);
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filter2_setup(device, FILTER_BANDPASS, fc, d, gain, filter2);
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}
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@ -1,133 +0,0 @@
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// license:BSD-3-Clause
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// copyright-holders:Derrick Renaud, Couriersud
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#pragma once
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#ifndef __FILTER_H__
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#define __FILTER_H__
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/* Max filter order */
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#define FILTER_ORDER_MAX 51
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/* Define to use integer calculation */
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#define FILTER_USE_INT
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#ifdef FILTER_USE_INT
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typedef int filter_real;
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#define FILTER_INT_FRACT 15 /* fractional bits */
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#else
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typedef double filter_real;
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#endif
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struct filter
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{
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filter_real xcoeffs[(FILTER_ORDER_MAX+1)/2];
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unsigned order;
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};
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struct filter_state
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{
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unsigned prev_mac;
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filter_real xprev[FILTER_ORDER_MAX];
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};
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/* Allocate a FIR Low Pass filter */
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filter* filter_lp_fir_alloc(double freq, int order);
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void filter_free(filter* f);
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/* Allocate a filter state */
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filter_state* filter_state_alloc(void);
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/* Free the filter state */
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void filter_state_free(filter_state* s);
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/* Clear the filter state */
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void filter_state_reset(filter* f, filter_state* s);
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/* Insert a value in the filter state */
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static inline void filter_insert(filter* f, filter_state* s, filter_real x) {
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/* next state */
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++s->prev_mac;
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if (s->prev_mac >= f->order)
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s->prev_mac = 0;
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/* set x[0] */
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s->xprev[s->prev_mac] = x;
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}
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/* Compute the filter output */
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filter_real filter_compute(filter* f, filter_state* s);
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/* Filter types */
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#define FILTER_LOWPASS 0
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#define FILTER_HIGHPASS 1
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#define FILTER_BANDPASS 2
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#define Q_TO_DAMP(q) (1.0/q)
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struct filter2_context
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{
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filter2_context() :
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x0(0.0),
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x1(0.0),
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x2(0.0),
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y0(0.0),
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y1(0.0),
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y2(0.0),
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a1(0.0),
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a2(0.0),
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b0(0.0),
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b1(0.0),
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b2(0.0)
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{}
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double x0, x1, x2; /* x[k], x[k-1], x[k-2], current and previous 2 input values */
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double y0, y1, y2; /* y[k], y[k-1], y[k-2], current and previous 2 output values */
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double a1, a2; /* digital filter coefficients, denominator */
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double b0, b1, b2; /* digital filter coefficients, numerator */
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};
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/* Setup the filter context based on the passed filter type info.
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* type - 1 of the 3 defined filter types
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* fc - center frequency
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* d - damp = 1/Q
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* gain - overall filter gain. Set to 1 if not needed.
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*/
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void filter2_setup(device_t *device, int type, double fc, double d, double gain,
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filter2_context *filter2);
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/* Reset the input/output voltages to 0. */
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void filter2_reset(filter2_context *filter2);
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/* Step the filter.
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* x0 is the new input, which needs to be set before stepping.
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* y0 is the new filter output.
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*/
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void filter2_step(filter2_context *filter2);
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/* Setup a filter2 structure based on an op-amp multipole bandpass circuit.
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* NOTE: If r2 is not used then set to 0.
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* vRef is not needed to setup filter.
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*
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* .--------+---------.
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* | | |
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* --- c1 Z |
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* --- Z r3 |
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* | Z |
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* r1 | c2 | |\ |
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* In >----ZZZZ----+---------+--||----+ | \ |
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* Z '--|- \ |
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* Z r2 | >--+------> out
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* Z .--|+ /
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* | | | /
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* gnd vRef >---' |/
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*
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*/
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void filter_opamp_m_bandpass_setup(device_t *device, double r1, double r2, double r3, double c1, double c2,
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filter2_context *filter2);
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#endif /* __FILTER_H__ */
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@ -36,7 +36,191 @@ static const double volume_table[8] =
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static const double r_filt_out[3] = {RES_K(4.7), RES_K(7.5), RES_K(10)};
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static const double r_filt_out[3] = {RES_K(4.7), RES_K(7.5), RES_K(10)};
|
||||||
static const double r_filt_total = 1.0 / (1.0/RES_K(4.7) + 1.0/RES_K(7.5) + 1.0/RES_K(10));
|
static const double r_filt_total = 1.0 / (1.0/RES_K(4.7) + 1.0/RES_K(7.5) + 1.0/RES_K(10));
|
||||||
|
|
||||||
|
/* Max filter order */
|
||||||
|
#define FILTER_ORDER_MAX 51
|
||||||
|
|
||||||
|
/* Define to use integer calculation */
|
||||||
|
#define FILTER_USE_INT
|
||||||
|
|
||||||
|
#ifdef FILTER_USE_INT
|
||||||
|
typedef int filter_real;
|
||||||
|
#define FILTER_INT_FRACT 15 /* fractional bits */
|
||||||
|
#else
|
||||||
|
typedef double filter_real;
|
||||||
|
#endif
|
||||||
|
|
||||||
|
struct filter
|
||||||
|
{
|
||||||
|
filter_real xcoeffs[(FILTER_ORDER_MAX+1)/2];
|
||||||
|
unsigned order;
|
||||||
|
};
|
||||||
|
|
||||||
|
struct filter_state
|
||||||
|
{
|
||||||
|
unsigned prev_mac;
|
||||||
|
filter_real xprev[FILTER_ORDER_MAX];
|
||||||
|
};
|
||||||
|
|
||||||
|
/* Insert a value in the filter state */
|
||||||
|
static inline void filter_insert(filter* f, filter_state* s, filter_real x) {
|
||||||
|
/* next state */
|
||||||
|
++s->prev_mac;
|
||||||
|
if (s->prev_mac >= f->order)
|
||||||
|
s->prev_mac = 0;
|
||||||
|
|
||||||
|
/* set x[0] */
|
||||||
|
s->xprev[s->prev_mac] = x;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Filter types */
|
||||||
|
#define FILTER_LOWPASS 0
|
||||||
|
#define FILTER_HIGHPASS 1
|
||||||
|
#define FILTER_BANDPASS 2
|
||||||
|
|
||||||
|
#define Q_TO_DAMP(q) (1.0/q)
|
||||||
|
|
||||||
|
/* Setup the filter context based on the passed filter type info.
|
||||||
|
* type - 1 of the 3 defined filter types
|
||||||
|
* fc - center frequency
|
||||||
|
* d - damp = 1/Q
|
||||||
|
* gain - overall filter gain. Set to 1 if not needed.
|
||||||
|
*/
|
||||||
|
static void filter2_setup(device_t *device, int type, double fc, double d, double gain,
|
||||||
|
filter2_context *filter2);
|
||||||
|
|
||||||
|
|
||||||
|
/* Reset the input/output voltages to 0. */
|
||||||
|
static void filter2_reset(filter2_context *filter2);
|
||||||
|
|
||||||
|
|
||||||
|
/* Step the filter.
|
||||||
|
* x0 is the new input, which needs to be set before stepping.
|
||||||
|
* y0 is the new filter output.
|
||||||
|
*/
|
||||||
|
static void filter2_step(filter2_context *filter2);
|
||||||
|
|
||||||
|
|
||||||
|
/* Setup a filter2 structure based on an op-amp multipole bandpass circuit.
|
||||||
|
* NOTE: If r2 is not used then set to 0.
|
||||||
|
* vRef is not needed to setup filter.
|
||||||
|
*
|
||||||
|
* .--------+---------.
|
||||||
|
* | | |
|
||||||
|
* --- c1 Z |
|
||||||
|
* --- Z r3 |
|
||||||
|
* | Z |
|
||||||
|
* r1 | c2 | |\ |
|
||||||
|
* In >----ZZZZ----+---------+--||----+ | \ |
|
||||||
|
* Z '--|- \ |
|
||||||
|
* Z r2 | >--+------> out
|
||||||
|
* Z .--|+ /
|
||||||
|
* | | | /
|
||||||
|
* gnd vRef >---' |/
|
||||||
|
*
|
||||||
|
*/
|
||||||
|
static void filter_opamp_m_bandpass_setup(device_t *device, double r1, double r2, double r3, double c1, double c2,
|
||||||
|
filter2_context *filter2);
|
||||||
|
|
||||||
|
|
||||||
|
static void filter2_setup(device_t *device, int type, double fc, double d, double gain,
|
||||||
|
filter2_context *filter2)
|
||||||
|
{
|
||||||
|
int sample_rate = device->machine().sample_rate();
|
||||||
|
double w; /* cutoff freq, in radians/sec */
|
||||||
|
double w_squared;
|
||||||
|
double den; /* temp variable */
|
||||||
|
double two_over_T = 2*sample_rate;
|
||||||
|
double two_over_T_squared = two_over_T * two_over_T;
|
||||||
|
|
||||||
|
/* calculate digital filter coefficents */
|
||||||
|
/*w = 2.0*M_PI*fc; no pre-warping */
|
||||||
|
w = sample_rate*2.0*tan(M_PI*fc/sample_rate); /* pre-warping */
|
||||||
|
w_squared = w*w;
|
||||||
|
|
||||||
|
den = two_over_T_squared + d*w*two_over_T + w_squared;
|
||||||
|
|
||||||
|
filter2->a1 = 2.0*(-two_over_T_squared + w_squared)/den;
|
||||||
|
filter2->a2 = (two_over_T_squared - d*w*two_over_T + w_squared)/den;
|
||||||
|
|
||||||
|
switch (type)
|
||||||
|
{
|
||||||
|
case FILTER_LOWPASS:
|
||||||
|
filter2->b0 = filter2->b2 = w_squared/den;
|
||||||
|
filter2->b1 = 2.0*(filter2->b0);
|
||||||
|
break;
|
||||||
|
case FILTER_BANDPASS:
|
||||||
|
filter2->b0 = d*w*two_over_T/den;
|
||||||
|
filter2->b1 = 0.0;
|
||||||
|
filter2->b2 = -(filter2->b0);
|
||||||
|
break;
|
||||||
|
case FILTER_HIGHPASS:
|
||||||
|
filter2->b0 = filter2->b2 = two_over_T_squared/den;
|
||||||
|
filter2->b1 = -2.0*(filter2->b0);
|
||||||
|
break;
|
||||||
|
default:
|
||||||
|
device->logerror("filter2_setup() - Invalid filter type for 2nd order filter.");
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
|
||||||
|
filter2->b0 *= gain;
|
||||||
|
filter2->b1 *= gain;
|
||||||
|
filter2->b2 *= gain;
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
/* Reset the input/output voltages to 0. */
|
||||||
|
static void filter2_reset(filter2_context *filter2)
|
||||||
|
{
|
||||||
|
filter2->x0 = 0;
|
||||||
|
filter2->x1 = 0;
|
||||||
|
filter2->x2 = 0;
|
||||||
|
filter2->y0 = 0;
|
||||||
|
filter2->y1 = 0;
|
||||||
|
filter2->y2 = 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
/* Step the filter. */
|
||||||
|
static void filter2_step(filter2_context *filter2)
|
||||||
|
{
|
||||||
|
filter2->y0 = -filter2->a1 * filter2->y1 - filter2->a2 * filter2->y2 +
|
||||||
|
filter2->b0 * filter2->x0 + filter2->b1 * filter2->x1 + filter2->b2 * filter2->x2;
|
||||||
|
filter2->x2 = filter2->x1;
|
||||||
|
filter2->x1 = filter2->x0;
|
||||||
|
filter2->y2 = filter2->y1;
|
||||||
|
filter2->y1 = filter2->y0;
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
/* Setup a filter2 structure based on an op-amp multipole bandpass circuit. */
|
||||||
|
static void filter_opamp_m_bandpass_setup(device_t *device, double r1, double r2, double r3, double c1, double c2,
|
||||||
|
filter2_context *filter2)
|
||||||
|
{
|
||||||
|
double r_in, fc, d, gain;
|
||||||
|
|
||||||
|
if (r1 == 0)
|
||||||
|
{
|
||||||
|
device->logerror("filter_opamp_m_bandpass_setup() - r1 can not be 0");
|
||||||
|
return; /* Filter can not be setup. Undefined results. */
|
||||||
|
}
|
||||||
|
|
||||||
|
if (r2 == 0)
|
||||||
|
{
|
||||||
|
gain = 1;
|
||||||
|
r_in = r1;
|
||||||
|
}
|
||||||
|
else
|
||||||
|
{
|
||||||
|
gain = r2 / (r1 + r2);
|
||||||
|
r_in = 1.0 / (1.0/r1 + 1.0/r2);
|
||||||
|
}
|
||||||
|
|
||||||
|
fc = 1.0 / (2 * M_PI * sqrt(r_in * r3 * c1 * c2));
|
||||||
|
d = (c1 + c2) / sqrt(r3 / r_in * c1 * c2);
|
||||||
|
gain *= -r3 / r_in * c2 / (c1 + c2);
|
||||||
|
|
||||||
|
filter2_setup(device, FILTER_BANDPASS, fc, d, gain, filter2);
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
// device type definition
|
// device type definition
|
||||||
|
|||||||
@ -6,11 +6,32 @@
|
|||||||
|
|
||||||
*************************************************************************/
|
*************************************************************************/
|
||||||
|
|
||||||
#include "sound/filter.h"
|
|
||||||
#include "sound/namco.h"
|
#include "sound/namco.h"
|
||||||
#include "sound/tms5220.h"
|
#include "sound/tms5220.h"
|
||||||
#include "sound/discrete.h"
|
#include "sound/discrete.h"
|
||||||
|
|
||||||
|
struct filter2_context
|
||||||
|
{
|
||||||
|
filter2_context() :
|
||||||
|
x0(0.0),
|
||||||
|
x1(0.0),
|
||||||
|
x2(0.0),
|
||||||
|
y0(0.0),
|
||||||
|
y1(0.0),
|
||||||
|
y2(0.0),
|
||||||
|
a1(0.0),
|
||||||
|
a2(0.0),
|
||||||
|
b0(0.0),
|
||||||
|
b1(0.0),
|
||||||
|
b2(0.0)
|
||||||
|
{}
|
||||||
|
|
||||||
|
double x0, x1, x2; /* x[k], x[k-1], x[k-2], current and previous 2 input values */
|
||||||
|
double y0, y1, y2; /* y[k], y[k-1], y[k-2], current and previous 2 output values */
|
||||||
|
double a1, a2; /* digital filter coefficients, denominator */
|
||||||
|
double b0, b1, b2; /* digital filter coefficients, numerator */
|
||||||
|
};
|
||||||
|
|
||||||
|
|
||||||
class polepos_state : public driver_device
|
class polepos_state : public driver_device
|
||||||
{
|
{
|
||||||
|
|||||||
Loading…
Reference in New Issue
Block a user