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-rw-r--r--gst-libs/gst/resample/resample.c929
1 files changed, 0 insertions, 929 deletions
diff --git a/gst-libs/gst/resample/resample.c b/gst-libs/gst/resample/resample.c
deleted file mode 100644
index c73b1186..00000000
--- a/gst-libs/gst/resample/resample.c
+++ /dev/null
@@ -1,929 +0,0 @@
-/* Resampling library
- * Copyright (C) <2001> David A. Schleef <ds@schleef.org>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Library General Public
- * License as published by the Free Software Foundation; either
- * version 2 of the License, or any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Library General Public License for more details.
- *
- * You should have received a copy of the GNU Library General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 02111-1307, USA.
- */
-
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-#include <string.h>
-#include <math.h>
-#include <stdio.h>
-#include <stdlib.h>
-
-#include "private.h"
-#include <gst/gstplugin.h>
-#include <gst/gstversion.h>
-
-inline double
-sinc (double x)
-{
- if (x == 0)
- return 1;
- return sin (x) / x;
-}
-
-inline double
-window_func (double x)
-{
- x = 1 - x * x;
- return x * x;
-}
-
-signed short
-double_to_s16 (double x)
-{
- if (x < -32768) {
- printf ("clipped\n");
- return -32768;
- }
- if (x > 32767) {
- printf ("clipped\n");
- return -32767;
- }
- return rint (x);
-}
-
-signed short
-double_to_s16_ppcasm (double x)
-{
- if (x < -32768) {
- return -32768;
- }
- if (x > 32767) {
- return -32767;
- }
- return rint (x);
-}
-
-void
-gst_resample_init (gst_resample_t * r)
-{
- r->i_start = 0;
- if (r->filter_length & 1) {
- r->o_start = 0;
- } else {
- r->o_start = r->o_inc * 0.5;
- }
-
- memset (r->acc, 0, sizeof (r->acc));
-
- gst_resample_reinit (r);
-}
-
-void
-gst_resample_reinit (gst_resample_t * r)
-{
- /* i_inc is the number of samples that the output increments for
- * each input sample. o_inc is the opposite. */
- r->i_inc = (double) r->o_rate / r->i_rate;
- r->o_inc = (double) r->i_rate / r->o_rate;
-
- r->halftaps = (r->filter_length - 1.0) * 0.5;
-
- if (r->format == GST_RESAMPLE_S16) {
- switch (r->method) {
- default:
- case GST_RESAMPLE_NEAREST:
- r->scale = gst_resample_nearest_s16;
- break;
- case GST_RESAMPLE_BILINEAR:
- r->scale = gst_resample_bilinear_s16;
- break;
- case GST_RESAMPLE_SINC_SLOW:
- r->scale = gst_resample_sinc_s16;
- break;
- case GST_RESAMPLE_SINC:
- r->scale = gst_resample_sinc_ft_s16;
- break;
- }
- } else if (r->format == GST_RESAMPLE_FLOAT) {
- switch (r->method) {
- default:
- case GST_RESAMPLE_NEAREST:
- r->scale = gst_resample_nearest_float;
- break;
- case GST_RESAMPLE_BILINEAR:
- r->scale = gst_resample_bilinear_float;
- break;
- case GST_RESAMPLE_SINC_SLOW:
- r->scale = gst_resample_sinc_float;
- break;
- case GST_RESAMPLE_SINC:
- r->scale = gst_resample_sinc_ft_float;
- break;
- }
- } else {
- fprintf (stderr, "gst_resample: Unexpected format \"%d\"\n", r->format);
- }
-}
-
-void
-gst_resample_close (gst_resample_t * r)
-{
- if (r->buffer) {
- free (r->buffer);
- r->buffer = NULL;
- r->buffer_len = 0;
- }
- if (r->hack_union.s.out_tmp) {
- free (r->hack_union.s.out_tmp);
- r->hack_union.s.out_tmp = NULL;
- r->hack_union.s.out_tmp_len = 0;
- }
-
-}
-
-/*
- * Prepare to be confused.
- *
- * We keep a "timebase" that is based on output samples. The zero
- * of the timebase cooresponds to the next output sample that will
- * be written.
- *
- * i_start is the "time" that corresponds to the first input sample
- * in an incoming buffer. Since the output depends on input samples
- * ahead in time, i_start will tend to be around halftaps.
- *
- * i_start_buf is the time of the first sample in the temporary
- * buffer.
- */
-void
-gst_resample_scale (gst_resample_t * r, void *i_buf, unsigned int i_size)
-{
- int o_size;
-
- r->i_buf = i_buf;
-
- r->i_samples = i_size / 2 / r->channels;
-
- r->i_start_buf = r->i_start - r->filter_length * r->i_inc;
-
- /* i_start is the offset (in a given output sample) that is the
- * beginning of the current input buffer */
- r->i_end = r->i_start + r->i_inc * r->i_samples;
-
- r->o_samples = floor (r->i_end - r->halftaps * r->i_inc);
-
- o_size = r->o_samples * r->channels * 2;
- r->o_buf = r->get_buffer (r->priv, o_size);
-
- if (r->verbose) {
- printf ("gst_resample_scale: i_buf=%p i_size=%d\n", i_buf, i_size);
- printf ("gst_resample_scale: i_samples=%d o_samples=%d i_inc=%g o_buf=%p\n",
- r->i_samples, r->o_samples, r->i_inc, r->o_buf);
- printf ("gst_resample_scale: i_start=%g i_end=%g o_start=%g\n",
- r->i_start, r->i_end, r->o_start);
- }
-
- if ((r->filter_length + r->i_samples) * sizeof (double) * 2 > r->buffer_len) {
- int size = (r->filter_length + r->i_samples) * sizeof (double) * 2;
-
- if (r->verbose) {
- printf ("gst_resample temp buffer size=%d\n", size);
- }
- if (r->buffer)
- free (r->buffer);
- r->buffer_len = size;
- r->buffer = malloc (size);
- memset (r->buffer, 0, size);
- }
-
- if (r->format == GST_RESAMPLE_S16) {
- if (r->channels == 2) {
- conv_double_short (r->buffer + r->filter_length * sizeof (double) * 2,
- r->i_buf, r->i_samples * 2);
- } else {
- conv_double_short_dstr (r->buffer +
- r->filter_length * sizeof (double) * 2, r->i_buf, r->i_samples,
- sizeof (double) * 2);
- }
- } else if (r->format == GST_RESAMPLE_FLOAT) {
- if (r->channels == 2) {
- conv_double_float (r->buffer + r->filter_length * sizeof (double) * 2,
- r->i_buf, r->i_samples * 2);
- } else {
- conv_double_float_dstr (r->buffer +
- r->filter_length * sizeof (double) * 2, r->i_buf, r->i_samples,
- sizeof (double) * 2);
- }
- }
-
- r->scale (r);
-
- memcpy (r->buffer,
- r->buffer + r->i_samples * sizeof (double) * 2,
- r->filter_length * sizeof (double) * 2);
-
- /* updating times */
- r->i_start += r->i_samples * r->i_inc;
- r->o_start += r->o_samples * r->o_inc - r->i_samples;
-
- /* adjusting timebase zero */
- r->i_start -= r->o_samples;
-}
-
-void
-gst_resample_nearest_s16 (gst_resample_t * r)
-{
- signed short *i_ptr, *o_ptr;
- int i_count = 0;
- double a;
- int i;
-
- i_ptr = (signed short *) r->i_buf;
- o_ptr = (signed short *) r->o_buf;
-
- a = r->o_start;
- i_count = 0;
-#define SCALE_LOOP(COPY,INC) \
- for (i = 0; i < r->o_samples; i++) { \
- COPY; \
- a += r->o_inc; \
- while (a >= 1) { \
- a -= 1; \
- i_ptr+=INC; \
- i_count++; \
- } \
- o_ptr+=INC; \
- }
-
- switch (r->channels) {
- case 1:
- SCALE_LOOP (o_ptr[0] = i_ptr[0], 1);
- break;
- case 2:
- SCALE_LOOP (o_ptr[0] = i_ptr[0];
- o_ptr[1] = i_ptr[1], 2);
- break;
- default:
- {
- int n, n_chan = r->channels;
-
- SCALE_LOOP (for (n = 0; n < n_chan; n++) o_ptr[n] = i_ptr[n], n_chan);
- }
- }
- if (i_count != r->i_samples) {
- printf ("handled %d in samples (expected %d)\n", i_count, r->i_samples);
- }
-}
-
-void
-gst_resample_bilinear_s16 (gst_resample_t * r)
-{
- signed short *i_ptr, *o_ptr;
- int o_count = 0;
- double b;
- int i;
- double acc0, acc1;
-
- i_ptr = (signed short *) r->i_buf;
- o_ptr = (signed short *) r->o_buf;
-
- acc0 = r->acc[0];
- acc1 = r->acc[1];
- b = r->i_start;
- for (i = 0; i < r->i_samples; i++) {
- b += r->i_inc;
- /*printf("in %d\n",i_ptr[0]); */
- if (b >= 2) {
- printf ("not expecting b>=2\n");
- }
- if (b >= 1) {
- acc0 += (1.0 - (b - r->i_inc)) * i_ptr[0];
- acc1 += (1.0 - (b - r->i_inc)) * i_ptr[1];
-
- o_ptr[0] = rint (acc0);
- /*printf("out %d\n",o_ptr[0]); */
- o_ptr[1] = rint (acc1);
- o_ptr += 2;
- o_count++;
-
- b -= 1.0;
-
- acc0 = b * i_ptr[0];
- acc1 = b * i_ptr[1];
- } else {
- acc0 += i_ptr[0] * r->i_inc;
- acc1 += i_ptr[1] * r->i_inc;
- }
- i_ptr += 2;
- }
- r->acc[0] = acc0;
- r->acc[1] = acc1;
-
- if (o_count != r->o_samples) {
- printf ("handled %d out samples (expected %d)\n", o_count, r->o_samples);
- }
-}
-
-void
-gst_resample_sinc_slow_s16 (gst_resample_t * r)
-{
- signed short *i_ptr, *o_ptr;
- int i, j;
- double c0, c1;
- double a;
- int start;
- double center;
- double weight;
-
- if (!r->buffer) {
- int size = r->filter_length * 2 * r->channels;
-
- printf ("gst_resample temp buffer\n");
- r->buffer = malloc (size);
- memset (r->buffer, 0, size);
- }
-
- i_ptr = (signed short *) r->i_buf;
- o_ptr = (signed short *) r->o_buf;
-
- a = r->i_start;
-#define GETBUF(index,chan) (((index)<0) \
- ? ((short *)(r->buffer))[((index)+r->filter_length)*2+(chan)] \
- : i_ptr[(index)*2+(chan)])
- {
- double sinx, cosx, sind, cosd;
- double x, d;
- double t;
-
- for (i = 0; i < r->o_samples; i++) {
- start = floor (a) - r->filter_length;
- center = a - r->halftaps;
- x = M_PI * (start - center) * r->o_inc;
- sinx = sin (M_PI * (start - center) * r->o_inc);
- cosx = cos (M_PI * (start - center) * r->o_inc);
- d = M_PI * r->o_inc;
- sind = sin (M_PI * r->o_inc);
- cosd = cos (M_PI * r->o_inc);
- c0 = 0;
- c1 = 0;
- for (j = 0; j < r->filter_length; j++) {
- weight = (x == 0) ? 1 : (sinx / x);
-/*printf("j %d sin %g cos %g\n",j,sinx,cosx); */
-/*printf("j %d sin %g x %g sinc %g\n",j,sinx,x,weight); */
- c0 += weight * GETBUF ((start + j), 0);
- c1 += weight * GETBUF ((start + j), 1);
- t = cosx * cosd - sinx * sind;
- sinx = cosx * sind + sinx * cosd;
- cosx = t;
- x += d;
- }
- o_ptr[0] = rint (c0);
- o_ptr[1] = rint (c1);
- o_ptr += 2;
- a += r->o_inc;
- }
- }
-#undef GETBUF
-
- memcpy (r->buffer,
- i_ptr + (r->i_samples - r->filter_length) * r->channels,
- r->filter_length * 2 * r->channels);
-}
-
-/* only works for channels == 2 ???? */
-void
-gst_resample_sinc_s16 (gst_resample_t * r)
-{
- double *ptr;
- signed short *o_ptr;
- int i, j;
- double c0, c1;
- double a;
- int start;
- double center;
- double weight;
- double x0, x, d;
- double scale;
-
- ptr = (double *) r->buffer;
- o_ptr = (signed short *) r->o_buf;
-
- /* scale provides a cutoff frequency for the low
- * pass filter aspects of sinc(). scale=M_PI
- * will cut off at the input frequency, which is
- * good for up-sampling, but will cause aliasing
- * for downsampling. Downsampling needs to be
- * cut off at o_rate, thus scale=M_PI*r->i_inc. */
- /* actually, it needs to be M_PI*r->i_inc*r->i_inc.
- * Need to research why. */
- scale = M_PI * r->i_inc;
- for (i = 0; i < r->o_samples; i++) {
- a = r->o_start + i * r->o_inc;
- start = floor (a - r->halftaps);
-/*printf("%d: a=%g start=%d end=%d\n",i,a,start,start+r->filter_length-1); */
- center = a;
- /*x = M_PI * (start - center) * r->o_inc; */
- /*d = M_PI * r->o_inc; */
- /*x = (start - center) * r->o_inc; */
- x0 = (start - center) * r->o_inc;
- d = r->o_inc;
- c0 = 0;
- c1 = 0;
- for (j = 0; j < r->filter_length; j++) {
- x = x0 + d * j;
- weight = sinc (x * scale * r->i_inc) * scale / M_PI;
- weight *= window_func (x / r->halftaps * r->i_inc);
- c0 += weight * ptr[(start + j + r->filter_length) * 2 + 0];
- c1 += weight * ptr[(start + j + r->filter_length) * 2 + 1];
- }
- o_ptr[0] = double_to_s16 (c0);
- o_ptr[1] = double_to_s16 (c1);
- o_ptr += 2;
- }
-}
-
-/*
- * Resampling audio is best done using a sinc() filter.
- *
- *
- * out[t] = Sum( in[t'] * sinc((t-t')/delta_t), all t')
- *
- * The immediate problem with this algorithm is that it involves a
- * sum over an infinite number of input samples, both in the past
- * and future. Note that even though sinc(x) is bounded by 1/x,
- * and thus decays to 0 for large x, since sum(x,{x=0,1..,n}) diverges
- * as log(n), we need to be careful about convergence. This is
- * typically done by using a windowing function, which also makes
- * the sum over a finite number of input samples.
- *
- * The next problem is computational: sinc(), and especially
- * sinc() multiplied by a non-trivial windowing function is expensive
- * to calculate, and also difficult to find SIMD optimizations. Since
- * the time increment on input and output is different, it is not
- * possible to use a FIR filter, because the taps would have to be
- * recalculated for every t.
- *
- * To get around the expense of calculating sinc() for every point,
- * we pre-calculate sinc() at a number of points, and then interpolate
- * for the values we want in calculations. The interpolation method
- * chosen is bi-cubic, which requires both the evalated function and
- * its derivative at every pre-sampled point. Also, if the sampled
- * points are spaced commensurate with the input delta_t, we notice
- * that the interpolating weights are the same for every input point.
- * This decreases the number of operations to 4 multiplies and 4 adds
- * for each tap, regardless of the complexity of the filtering function.
- *
- * At this point, it is possible to rearrange the problem as the sum
- * of 4 properly weghted FIR filters. Typical SIMD computation units
- * are highly optimized for FIR filters, making long filter lengths
- * reasonable.
- */
-
-static functable_t *ft;
-
-void
-gst_resample_sinc_ft_s16 (gst_resample_t * r)
-{
- double *ptr;
- signed short *o_ptr;
- int i;
-
- /*int j; */
- double c0, c1;
-
- /*double a; */
- double start_f, start_x;
- int start;
- double center;
-
- /*double weight; */
- double x, d;
- double scale;
- int n = 4;
- double *out_tmp;
-
- if (r->hack_union.s.out_tmp_len < r->o_samples) {
- r->hack_union.s.out_tmp = realloc (r->hack_union.s.out_tmp,
- r->o_samples * 2 * sizeof (double));
- r->hack_union.s.out_tmp_len = r->o_samples;
- }
- out_tmp = r->hack_union.s.out_tmp;
-
- scale = r->i_inc; /* cutoff at 22050 */
- /*scale = 1.0; // cutoff at 24000 */
- /*scale = r->i_inc * 0.5; // cutoff at 11025 */
-
- if (!ft) {
- ft = malloc (sizeof (*ft));
- memset (ft, 0, sizeof (*ft));
-
- ft->len = (r->filter_length + 2) * n;
- ft->offset = 1.0 / n;
- ft->start = -ft->len * 0.5 * ft->offset;
-
- ft->func_x = functable_sinc;
- ft->func_dx = functable_dsinc;
- ft->scale = M_PI * scale;
-
- ft->func2_x = functable_window_std;
- ft->func2_dx = functable_window_dstd;
- ft->scale2 = 1.0 / r->halftaps;
-
- functable_init (ft);
-
- /*printf("len=%d offset=%g start=%g\n",ft->len,ft->offset,ft->start); */
- }
-
- ptr = r->buffer;
- o_ptr = (signed short *) r->o_buf;
-
- center = r->o_start;
- while (center - r->halftaps < -1 * r->filter_length)
- center += 1.0;
- start_x = center - r->halftaps;
- start_f = floor (start_x);
- start_x -= start_f;
- start = start_f;
- for (i = 0; i < r->o_samples; i++) {
- /*start_f = floor(center - r->halftaps); */
-/*printf("%d: a=%g start=%d end=%d\n",i,a,start,start+r->filter_length-1); */
- x = start_f - center;
- d = 1;
- c0 = 0;
- c1 = 0;
-/*#define slow */
-#ifdef slow
- for (j = 0; j < r->filter_length; j++) {
- weight = functable_eval (ft, x) * scale;
- /*weight = sinc(M_PI * scale * x)*scale*r->i_inc; */
- /*weight *= window_func(x / r->halftaps); */
- c0 += weight * ptr[(start + j + r->filter_length) * 2 + 0];
- c1 += weight * ptr[(start + j + r->filter_length) * 2 + 1];
- x += d;
- }
-#else
- functable_fir2 (ft,
- &c0, &c1, x, n, ptr + (start + r->filter_length) * 2, r->filter_length);
- c0 *= scale;
- c1 *= scale;
-#endif
-
- out_tmp[2 * i + 0] = c0;
- out_tmp[2 * i + 1] = c1;
- center += r->o_inc;
- start_x += r->o_inc;
- while (start_x >= 1.0) {
- start_f++;
- start_x -= 1.0;
- start++;
- }
- }
-
- if (r->channels == 2) {
- conv_short_double (r->o_buf, out_tmp, 2 * r->o_samples);
- } else {
- conv_short_double_sstr (r->o_buf, out_tmp, r->o_samples,
- 2 * sizeof (double));
- }
-}
-
-/********
- ** float code below
- ********/
-
-
-void
-gst_resample_nearest_float (gst_resample_t * r)
-{
- float *i_ptr, *o_ptr;
- int i_count = 0;
- double a;
- int i;
-
- i_ptr = (float *) r->i_buf;
- o_ptr = (float *) r->o_buf;
-
- a = r->o_start;
- i_count = 0;
-#define SCALE_LOOP(COPY,INC) \
- for (i = 0; i < r->o_samples; i++) { \
- COPY; \
- a += r->o_inc; \
- while (a >= 1) { \
- a -= 1; \
- i_ptr+=INC; \
- i_count++; \
- } \
- o_ptr+=INC; \
- }
-
- switch (r->channels) {
- case 1:
- SCALE_LOOP (o_ptr[0] = i_ptr[0], 1);
- break;
- case 2:
- SCALE_LOOP (o_ptr[0] = i_ptr[0];
- o_ptr[1] = i_ptr[1], 2);
- break;
- default:
- {
- int n, n_chan = r->channels;
-
- SCALE_LOOP (for (n = 0; n < n_chan; n++) o_ptr[n] = i_ptr[n], n_chan);
- }
- }
- if (i_count != r->i_samples) {
- printf ("handled %d in samples (expected %d)\n", i_count, r->i_samples);
- }
-}
-
-void
-gst_resample_bilinear_float (gst_resample_t * r)
-{
- float *i_ptr, *o_ptr;
- int o_count = 0;
- double b;
- int i;
- double acc0, acc1;
-
- i_ptr = (float *) r->i_buf;
- o_ptr = (float *) r->o_buf;
-
- acc0 = r->acc[0];
- acc1 = r->acc[1];
- b = r->i_start;
- for (i = 0; i < r->i_samples; i++) {
- b += r->i_inc;
- /*printf("in %d\n",i_ptr[0]); */
- if (b >= 2) {
- printf ("not expecting b>=2\n");
- }
- if (b >= 1) {
- acc0 += (1.0 - (b - r->i_inc)) * i_ptr[0];
- acc1 += (1.0 - (b - r->i_inc)) * i_ptr[1];
-
- o_ptr[0] = acc0;
- /*printf("out %d\n",o_ptr[0]); */
- o_ptr[1] = acc1;
- o_ptr += 2;
- o_count++;
-
- b -= 1.0;
-
- acc0 = b * i_ptr[0];
- acc1 = b * i_ptr[1];
- } else {
- acc0 += i_ptr[0] * r->i_inc;
- acc1 += i_ptr[1] * r->i_inc;
- }
- i_ptr += 2;
- }
- r->acc[0] = acc0;
- r->acc[1] = acc1;
-
- if (o_count != r->o_samples) {
- printf ("handled %d out samples (expected %d)\n", o_count, r->o_samples);
- }
-}
-
-void
-gst_resample_sinc_slow_float (gst_resample_t * r)
-{
- float *i_ptr, *o_ptr;
- int i, j;
- double c0, c1;
- double a;
- int start;
- double center;
- double weight;
-
- if (!r->buffer) {
- int size = r->filter_length * sizeof (float) * r->channels;
-
- printf ("gst_resample temp buffer\n");
- r->buffer = malloc (size);
- memset (r->buffer, 0, size);
- }
-
- i_ptr = (float *) r->i_buf;
- o_ptr = (float *) r->o_buf;
-
- a = r->i_start;
-#define GETBUF(index,chan) (((index)<0) \
- ? ((float *)(r->buffer))[((index)+r->filter_length)*2+(chan)] \
- : i_ptr[(index)*2+(chan)])
- {
- double sinx, cosx, sind, cosd;
- double x, d;
- double t;
-
- for (i = 0; i < r->o_samples; i++) {
- start = floor (a) - r->filter_length;
- center = a - r->halftaps;
- x = M_PI * (start - center) * r->o_inc;
- sinx = sin (M_PI * (start - center) * r->o_inc);
- cosx = cos (M_PI * (start - center) * r->o_inc);
- d = M_PI * r->o_inc;
- sind = sin (M_PI * r->o_inc);
- cosd = cos (M_PI * r->o_inc);
- c0 = 0;
- c1 = 0;
- for (j = 0; j < r->filter_length; j++) {
- weight = (x == 0) ? 1 : (sinx / x);
-/*printf("j %d sin %g cos %g\n",j,sinx,cosx); */
-/*printf("j %d sin %g x %g sinc %g\n",j,sinx,x,weight); */
- c0 += weight * GETBUF ((start + j), 0);
- c1 += weight * GETBUF ((start + j), 1);
- t = cosx * cosd - sinx * sind;
- sinx = cosx * sind + sinx * cosd;
- cosx = t;
- x += d;
- }
- o_ptr[0] = c0;
- o_ptr[1] = c1;
- o_ptr += 2;
- a += r->o_inc;
- }
- }
-#undef GETBUF
-
- memcpy (r->buffer,
- i_ptr + (r->i_samples - r->filter_length) * r->channels,
- r->filter_length * sizeof (float) * r->channels);
-}
-
-/* only works for channels == 2 ???? */
-void
-gst_resample_sinc_float (gst_resample_t * r)
-{
- double *ptr;
- float *o_ptr;
- int i, j;
- double c0, c1;
- double a;
- int start;
- double center;
- double weight;
- double x0, x, d;
- double scale;
-
- ptr = (double *) r->buffer;
- o_ptr = (float *) r->o_buf;
-
- /* scale provides a cutoff frequency for the low
- * pass filter aspects of sinc(). scale=M_PI
- * will cut off at the input frequency, which is
- * good for up-sampling, but will cause aliasing
- * for downsampling. Downsampling needs to be
- * cut off at o_rate, thus scale=M_PI*r->i_inc. */
- /* actually, it needs to be M_PI*r->i_inc*r->i_inc.
- * Need to research why. */
- scale = M_PI * r->i_inc;
- for (i = 0; i < r->o_samples; i++) {
- a = r->o_start + i * r->o_inc;
- start = floor (a - r->halftaps);
-/*printf("%d: a=%g start=%d end=%d\n",i,a,start,start+r->filter_length-1); */
- center = a;
- /*x = M_PI * (start - center) * r->o_inc; */
- /*d = M_PI * r->o_inc; */
- /*x = (start - center) * r->o_inc; */
- x0 = (start - center) * r->o_inc;
- d = r->o_inc;
- c0 = 0;
- c1 = 0;
- for (j = 0; j < r->filter_length; j++) {
- x = x0 + d * j;
- weight = sinc (x * scale * r->i_inc) * scale / M_PI;
- weight *= window_func (x / r->halftaps * r->i_inc);
- c0 += weight * ptr[(start + j + r->filter_length) * 2 + 0];
- c1 += weight * ptr[(start + j + r->filter_length) * 2 + 1];
- }
- o_ptr[0] = c0;
- o_ptr[1] = c1;
- o_ptr += 2;
- }
-}
-
-void
-gst_resample_sinc_ft_float (gst_resample_t * r)
-{
- double *ptr;
- float *o_ptr;
- int i;
-
- /*int j; */
- double c0, c1;
-
- /*double a; */
- double start_f, start_x;
- int start;
- double center;
-
- /*double weight; */
- double x, d;
- double scale;
- int n = 4;
- double *out_tmp;
-
- if (r->hack_union.s.out_tmp_len < r->o_samples) {
- r->hack_union.s.out_tmp = realloc (r->hack_union.s.out_tmp,
- r->o_samples * 2 * sizeof (double));
- r->hack_union.s.out_tmp_len = r->o_samples;
- }
- out_tmp = r->hack_union.s.out_tmp;
-
- scale = r->i_inc; /* cutoff at 22050 */
- /*scale = 1.0; // cutoff at 24000 */
- /*scale = r->i_inc * 0.5; // cutoff at 11025 */
-
- if (!ft) {
- ft = malloc (sizeof (*ft));
- memset (ft, 0, sizeof (*ft));
-
- ft->len = (r->filter_length + 2) * n;
- ft->offset = 1.0 / n;
- ft->start = -ft->len * 0.5 * ft->offset;
-
- ft->func_x = functable_sinc;
- ft->func_dx = functable_dsinc;
- ft->scale = M_PI * scale;
-
- ft->func2_x = functable_window_std;
- ft->func2_dx = functable_window_dstd;
- ft->scale2 = 1.0 / r->halftaps;
-
- functable_init (ft);
-
- /*printf("len=%d offset=%g start=%g\n",ft->len,ft->offset,ft->start); */
- }
-
- ptr = r->buffer;
- o_ptr = (float *) r->o_buf;
-
- center = r->o_start;
- start_x = center - r->halftaps;
- start_f = floor (start_x);
- start_x -= start_f;
- start = start_f;
- for (i = 0; i < r->o_samples; i++) {
- /*start_f = floor(center - r->halftaps); */
-/*printf("%d: a=%g start=%d end=%d\n",i,a,start,start+r->filter_length-1); */
- x = start_f - center;
- d = 1;
- c0 = 0;
- c1 = 0;
-/*#define slow */
-#ifdef slow
- for (j = 0; j < r->filter_length; j++) {
- weight = functable_eval (ft, x) * scale;
- /*weight = sinc(M_PI * scale * x)*scale*r->i_inc; */
- /*weight *= window_func(x / r->halftaps); */
- c0 += weight * ptr[(start + j + r->filter_length) * 2 + 0];
- c1 += weight * ptr[(start + j + r->filter_length) * 2 + 1];
- x += d;
- }
-#else
- functable_fir2 (ft,
- &c0, &c1, x, n, ptr + (start + r->filter_length) * 2, r->filter_length);
- c0 *= scale;
- c1 *= scale;
-#endif
-
- out_tmp[2 * i + 0] = c0;
- out_tmp[2 * i + 1] = c1;
- center += r->o_inc;
- start_x += r->o_inc;
- while (start_x >= 1.0) {
- start_f++;
- start_x -= 1.0;
- start++;
- }
- }
-
- if (r->channels == 2) {
- conv_float_double (r->o_buf, out_tmp, 2 * r->o_samples);
- } else {
- conv_float_double_sstr (r->o_buf, out_tmp, r->o_samples,
- 2 * sizeof (double));
- }
-}
-
-static gboolean
-plugin_init (GstPlugin * plugin)
-{
- return TRUE;
-}
-
-GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
- GST_VERSION_MINOR,
- "gstresample",
- "Resampling routines for use in audio plugins",
- plugin_init, VERSION, GST_LICENSE, GST_PACKAGE, GST_ORIGIN);
generated by cgit v1.2.1 (git 2.18.0) at 2024-07-03 08:41:10 +0000