--- /dev/null
+/*
+** Copyright (c) 2002-2016, Erik de Castro Lopo <erikd@mega-nerd.com>
+** All rights reserved.
+**
+** This code is released under 2-clause BSD license. Please see the
+** file at : https://github.com/erikd/libsamplerate/blob/master/COPYING
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "config.h"
+#include "float_cast.h"
+#include "common.h"
+
+#define SINC_MAGIC_MARKER MAKE_MAGIC (' ', 's', 'i', 'n', 'c', ' ')
+
+/*========================================================================================
+*/
+
+#define MAKE_INCREMENT_T(x) ((increment_t) (x))
+
+#define SHIFT_BITS 12
+#define FP_ONE ((double) (((increment_t) 1) << SHIFT_BITS))
+#define INV_FP_ONE (1.0 / FP_ONE)
+
+/*========================================================================================
+*/
+
+typedef int32_t increment_t ;
+typedef float coeff_t ;
+
+#include "fastest_coeffs.h"
+#include "mid_qual_coeffs.h"
+#include "high_qual_coeffs.h"
+
+typedef struct
+{ int sinc_magic_marker ;
+
+ int channels ;
+ long in_count, in_used ;
+ long out_count, out_gen ;
+
+ int coeff_half_len, index_inc ;
+
+ double src_ratio, input_index ;
+
+ coeff_t const *coeffs ;
+
+ int b_current, b_end, b_real_end, b_len ;
+
+ /* Sure hope noone does more than 128 channels at once. */
+ double left_calc [128], right_calc [128] ;
+
+ /* C99 struct flexible array. */
+ float buffer [] ;
+} SINC_FILTER ;
+
+static int sinc_multichan_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data) ;
+static int sinc_hex_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data) ;
+static int sinc_quad_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data) ;
+static int sinc_stereo_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data) ;
+static int sinc_mono_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data) ;
+
+static int prepare_data (SINC_FILTER *filter, SRC_DATA *data, int half_filter_chan_len) WARN_UNUSED ;
+
+static void sinc_reset (SRC_PRIVATE *psrc) ;
+
+static inline increment_t
+double_to_fp (double x)
+{ return (lrint ((x) * FP_ONE)) ;
+} /* double_to_fp */
+
+static inline increment_t
+int_to_fp (int x)
+{ return (((increment_t) (x)) << SHIFT_BITS) ;
+} /* int_to_fp */
+
+static inline int
+fp_to_int (increment_t x)
+{ return (((x) >> SHIFT_BITS)) ;
+} /* fp_to_int */
+
+static inline increment_t
+fp_fraction_part (increment_t x)
+{ return ((x) & ((((increment_t) 1) << SHIFT_BITS) - 1)) ;
+} /* fp_fraction_part */
+
+static inline double
+fp_to_double (increment_t x)
+{ return fp_fraction_part (x) * INV_FP_ONE ;
+} /* fp_to_double */
+
+
+/*----------------------------------------------------------------------------------------
+*/
+
+const char*
+sinc_get_name (int src_enum)
+{
+ switch (src_enum)
+ { case SRC_SINC_BEST_QUALITY :
+ return "Best Sinc Interpolator" ;
+
+ case SRC_SINC_MEDIUM_QUALITY :
+ return "Medium Sinc Interpolator" ;
+
+ case SRC_SINC_FASTEST :
+ return "Fastest Sinc Interpolator" ;
+
+ default: break ;
+ } ;
+
+ return NULL ;
+} /* sinc_get_descrition */
+
+const char*
+sinc_get_description (int src_enum)
+{
+ switch (src_enum)
+ { case SRC_SINC_FASTEST :
+ return "Band limited sinc interpolation, fastest, 97dB SNR, 80% BW." ;
+
+ case SRC_SINC_MEDIUM_QUALITY :
+ return "Band limited sinc interpolation, medium quality, 121dB SNR, 90% BW." ;
+
+ case SRC_SINC_BEST_QUALITY :
+ return "Band limited sinc interpolation, best quality, 144dB SNR, 96% BW." ;
+
+ default :
+ break ;
+ } ;
+
+ return NULL ;
+} /* sinc_get_descrition */
+
+int
+sinc_set_converter (SRC_PRIVATE *psrc, int src_enum)
+{ SINC_FILTER *filter, temp_filter ;
+ increment_t count ;
+ int bits ;
+
+ /* Quick sanity check. */
+ if (SHIFT_BITS >= sizeof (increment_t) * 8 - 1)
+ return SRC_ERR_SHIFT_BITS ;
+
+ if (psrc->private_data != NULL)
+ { free (psrc->private_data) ;
+ psrc->private_data = NULL ;
+ } ;
+
+ memset (&temp_filter, 0, sizeof (temp_filter)) ;
+
+ temp_filter.sinc_magic_marker = SINC_MAGIC_MARKER ;
+ temp_filter.channels = psrc->channels ;
+
+ if (psrc->channels > ARRAY_LEN (temp_filter.left_calc))
+ return SRC_ERR_BAD_CHANNEL_COUNT ;
+ else if (psrc->channels == 1)
+ { psrc->const_process = sinc_mono_vari_process ;
+ psrc->vari_process = sinc_mono_vari_process ;
+ }
+ else
+ if (psrc->channels == 2)
+ { psrc->const_process = sinc_stereo_vari_process ;
+ psrc->vari_process = sinc_stereo_vari_process ;
+ }
+ else
+ if (psrc->channels == 4)
+ { psrc->const_process = sinc_quad_vari_process ;
+ psrc->vari_process = sinc_quad_vari_process ;
+ }
+ else
+ if (psrc->channels == 6)
+ { psrc->const_process = sinc_hex_vari_process ;
+ psrc->vari_process = sinc_hex_vari_process ;
+ }
+ else
+ { psrc->const_process = sinc_multichan_vari_process ;
+ psrc->vari_process = sinc_multichan_vari_process ;
+ } ;
+ psrc->reset = sinc_reset ;
+
+ switch (src_enum)
+ { case SRC_SINC_FASTEST :
+ temp_filter.coeffs = fastest_coeffs.coeffs ;
+ temp_filter.coeff_half_len = ARRAY_LEN (fastest_coeffs.coeffs) - 2 ;
+ temp_filter.index_inc = fastest_coeffs.increment ;
+ break ;
+
+ case SRC_SINC_MEDIUM_QUALITY :
+ temp_filter.coeffs = slow_mid_qual_coeffs.coeffs ;
+ temp_filter.coeff_half_len = ARRAY_LEN (slow_mid_qual_coeffs.coeffs) - 2 ;
+ temp_filter.index_inc = slow_mid_qual_coeffs.increment ;
+ break ;
+
+ case SRC_SINC_BEST_QUALITY :
+ temp_filter.coeffs = slow_high_qual_coeffs.coeffs ;
+ temp_filter.coeff_half_len = ARRAY_LEN (slow_high_qual_coeffs.coeffs) - 2 ;
+ temp_filter.index_inc = slow_high_qual_coeffs.increment ;
+ break ;
+
+ default :
+ return SRC_ERR_BAD_CONVERTER ;
+ } ;
+
+ /*
+ ** FIXME : This needs to be looked at more closely to see if there is
+ ** a better way. Need to look at prepare_data () at the same time.
+ */
+
+ temp_filter.b_len = lrint (2.5 * temp_filter.coeff_half_len / (temp_filter.index_inc * 1.0) * SRC_MAX_RATIO) ;
+ temp_filter.b_len = MAX (temp_filter.b_len, 4096) ;
+ temp_filter.b_len *= temp_filter.channels ;
+
+ if ((filter = calloc (1, sizeof (SINC_FILTER) + sizeof (filter->buffer [0]) * (temp_filter.b_len + temp_filter.channels))) == NULL)
+ return SRC_ERR_MALLOC_FAILED ;
+
+ *filter = temp_filter ;
+ memset (&temp_filter, 0xEE, sizeof (temp_filter)) ;
+
+ psrc->private_data = filter ;
+
+ sinc_reset (psrc) ;
+
+ count = filter->coeff_half_len ;
+ for (bits = 0 ; (MAKE_INCREMENT_T (1) << bits) < count ; bits++)
+ count |= (MAKE_INCREMENT_T (1) << bits) ;
+
+ if (bits + SHIFT_BITS - 1 >= (int) (sizeof (increment_t) * 8))
+ return SRC_ERR_FILTER_LEN ;
+
+ return SRC_ERR_NO_ERROR ;
+} /* sinc_set_converter */
+
+static void
+sinc_reset (SRC_PRIVATE *psrc)
+{ SINC_FILTER *filter ;
+
+ filter = (SINC_FILTER*) psrc->private_data ;
+ if (filter == NULL)
+ return ;
+
+ filter->b_current = filter->b_end = 0 ;
+ filter->b_real_end = -1 ;
+
+ filter->src_ratio = filter->input_index = 0.0 ;
+
+ memset (filter->buffer, 0, filter->b_len * sizeof (filter->buffer [0])) ;
+
+ /* Set this for a sanity check */
+ memset (filter->buffer + filter->b_len, 0xAA, filter->channels * sizeof (filter->buffer [0])) ;
+} /* sinc_reset */
+
+/*========================================================================================
+** Beware all ye who dare pass this point. There be dragons here.
+*/
+
+static inline double
+calc_output_single (SINC_FILTER *filter, increment_t increment, increment_t start_filter_index)
+{ double fraction, left, right, icoeff ;
+ increment_t filter_index, max_filter_index ;
+ int data_index, coeff_count, indx ;
+
+ /* Convert input parameters into fixed point. */
+ max_filter_index = int_to_fp (filter->coeff_half_len) ;
+
+ /* First apply the left half of the filter. */
+ filter_index = start_filter_index ;
+ coeff_count = (max_filter_index - filter_index) / increment ;
+ filter_index = filter_index + coeff_count * increment ;
+ data_index = filter->b_current - coeff_count ;
+
+ left = 0.0 ;
+ do
+ { fraction = fp_to_double (filter_index) ;
+ indx = fp_to_int (filter_index) ;
+
+ icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ;
+
+ left += icoeff * filter->buffer [data_index] ;
+
+ filter_index -= increment ;
+ data_index = data_index + 1 ;
+ }
+ while (filter_index >= MAKE_INCREMENT_T (0)) ;
+
+ /* Now apply the right half of the filter. */
+ filter_index = increment - start_filter_index ;
+ coeff_count = (max_filter_index - filter_index) / increment ;
+ filter_index = filter_index + coeff_count * increment ;
+ data_index = filter->b_current + 1 + coeff_count ;
+
+ right = 0.0 ;
+ do
+ { fraction = fp_to_double (filter_index) ;
+ indx = fp_to_int (filter_index) ;
+
+ icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ;
+
+ right += icoeff * filter->buffer [data_index] ;
+
+ filter_index -= increment ;
+ data_index = data_index - 1 ;
+ }
+ while (filter_index > MAKE_INCREMENT_T (0)) ;
+
+ return (left + right) ;
+} /* calc_output_single */
+
+static int
+sinc_mono_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data)
+{ SINC_FILTER *filter ;
+ double input_index, src_ratio, count, float_increment, terminate, rem ;
+ increment_t increment, start_filter_index ;
+ int half_filter_chan_len, samples_in_hand ;
+
+ if (psrc->private_data == NULL)
+ return SRC_ERR_NO_PRIVATE ;
+
+ filter = (SINC_FILTER*) psrc->private_data ;
+
+ /* If there is not a problem, this will be optimised out. */
+ if (sizeof (filter->buffer [0]) != sizeof (data->data_in [0]))
+ return SRC_ERR_SIZE_INCOMPATIBILITY ;
+
+ filter->in_count = data->input_frames * filter->channels ;
+ filter->out_count = data->output_frames * filter->channels ;
+ filter->in_used = filter->out_gen = 0 ;
+
+ src_ratio = psrc->last_ratio ;
+
+ if (is_bad_src_ratio (src_ratio))
+ return SRC_ERR_BAD_INTERNAL_STATE ;
+
+ /* Check the sample rate ratio wrt the buffer len. */
+ count = (filter->coeff_half_len + 2.0) / filter->index_inc ;
+ if (MIN (psrc->last_ratio, data->src_ratio) < 1.0)
+ count /= MIN (psrc->last_ratio, data->src_ratio) ;
+
+ /* Maximum coefficientson either side of center point. */
+ half_filter_chan_len = filter->channels * (lrint (count) + 1) ;
+
+ input_index = psrc->last_position ;
+ float_increment = filter->index_inc ;
+
+ rem = fmod_one (input_index) ;
+ filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ;
+ input_index = rem ;
+
+ terminate = 1.0 / src_ratio + 1e-20 ;
+
+ /* Main processing loop. */
+ while (filter->out_gen < filter->out_count)
+ {
+ /* Need to reload buffer? */
+ samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ;
+
+ if (samples_in_hand <= half_filter_chan_len)
+ { if ((psrc->error = prepare_data (filter, data, half_filter_chan_len)) != 0)
+ return psrc->error ;
+
+ samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ;
+ if (samples_in_hand <= half_filter_chan_len)
+ break ;
+ } ;
+
+ /* This is the termination condition. */
+ if (filter->b_real_end >= 0)
+ { if (filter->b_current + input_index + terminate > filter->b_real_end)
+ break ;
+ } ;
+
+ if (filter->out_count > 0 && fabs (psrc->last_ratio - data->src_ratio) > 1e-10)
+ src_ratio = psrc->last_ratio + filter->out_gen * (data->src_ratio - psrc->last_ratio) / filter->out_count ;
+
+ float_increment = filter->index_inc * (src_ratio < 1.0 ? src_ratio : 1.0) ;
+ increment = double_to_fp (float_increment) ;
+
+ start_filter_index = double_to_fp (input_index * float_increment) ;
+
+ data->data_out [filter->out_gen] = (float) ((float_increment / filter->index_inc) *
+ calc_output_single (filter, increment, start_filter_index)) ;
+ filter->out_gen ++ ;
+
+ /* Figure out the next index. */
+ input_index += 1.0 / src_ratio ;
+ rem = fmod_one (input_index) ;
+
+ filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ;
+ input_index = rem ;
+ } ;
+
+ psrc->last_position = input_index ;
+
+ /* Save current ratio rather then target ratio. */
+ psrc->last_ratio = src_ratio ;
+
+ data->input_frames_used = filter->in_used / filter->channels ;
+ data->output_frames_gen = filter->out_gen / filter->channels ;
+
+ return SRC_ERR_NO_ERROR ;
+} /* sinc_mono_vari_process */
+
+static inline void
+calc_output_stereo (SINC_FILTER *filter, increment_t increment, increment_t start_filter_index, double scale, float * output)
+{ double fraction, left [2], right [2], icoeff ;
+ increment_t filter_index, max_filter_index ;
+ int data_index, coeff_count, indx ;
+
+ /* Convert input parameters into fixed point. */
+ max_filter_index = int_to_fp (filter->coeff_half_len) ;
+
+ /* First apply the left half of the filter. */
+ filter_index = start_filter_index ;
+ coeff_count = (max_filter_index - filter_index) / increment ;
+ filter_index = filter_index + coeff_count * increment ;
+ data_index = filter->b_current - filter->channels * coeff_count ;
+
+ left [0] = left [1] = 0.0 ;
+ do
+ { fraction = fp_to_double (filter_index) ;
+ indx = fp_to_int (filter_index) ;
+
+ icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ;
+
+ left [0] += icoeff * filter->buffer [data_index] ;
+ left [1] += icoeff * filter->buffer [data_index + 1] ;
+
+ filter_index -= increment ;
+ data_index = data_index + 2 ;
+ }
+ while (filter_index >= MAKE_INCREMENT_T (0)) ;
+
+ /* Now apply the right half of the filter. */
+ filter_index = increment - start_filter_index ;
+ coeff_count = (max_filter_index - filter_index) / increment ;
+ filter_index = filter_index + coeff_count * increment ;
+ data_index = filter->b_current + filter->channels * (1 + coeff_count) ;
+
+ right [0] = right [1] = 0.0 ;
+ do
+ { fraction = fp_to_double (filter_index) ;
+ indx = fp_to_int (filter_index) ;
+
+ icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ;
+
+ right [0] += icoeff * filter->buffer [data_index] ;
+ right [1] += icoeff * filter->buffer [data_index + 1] ;
+
+ filter_index -= increment ;
+ data_index = data_index - 2 ;
+ }
+ while (filter_index > MAKE_INCREMENT_T (0)) ;
+
+ output [0] = scale * (left [0] + right [0]) ;
+ output [1] = scale * (left [1] + right [1]) ;
+} /* calc_output_stereo */
+
+static int
+sinc_stereo_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data)
+{ SINC_FILTER *filter ;
+ double input_index, src_ratio, count, float_increment, terminate, rem ;
+ increment_t increment, start_filter_index ;
+ int half_filter_chan_len, samples_in_hand ;
+
+ if (psrc->private_data == NULL)
+ return SRC_ERR_NO_PRIVATE ;
+
+ filter = (SINC_FILTER*) psrc->private_data ;
+
+ /* If there is not a problem, this will be optimised out. */
+ if (sizeof (filter->buffer [0]) != sizeof (data->data_in [0]))
+ return SRC_ERR_SIZE_INCOMPATIBILITY ;
+
+ filter->in_count = data->input_frames * filter->channels ;
+ filter->out_count = data->output_frames * filter->channels ;
+ filter->in_used = filter->out_gen = 0 ;
+
+ src_ratio = psrc->last_ratio ;
+
+ if (is_bad_src_ratio (src_ratio))
+ return SRC_ERR_BAD_INTERNAL_STATE ;
+
+ /* Check the sample rate ratio wrt the buffer len. */
+ count = (filter->coeff_half_len + 2.0) / filter->index_inc ;
+ if (MIN (psrc->last_ratio, data->src_ratio) < 1.0)
+ count /= MIN (psrc->last_ratio, data->src_ratio) ;
+
+ /* Maximum coefficientson either side of center point. */
+ half_filter_chan_len = filter->channels * (lrint (count) + 1) ;
+
+ input_index = psrc->last_position ;
+ float_increment = filter->index_inc ;
+
+ rem = fmod_one (input_index) ;
+ filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ;
+ input_index = rem ;
+
+ terminate = 1.0 / src_ratio + 1e-20 ;
+
+ /* Main processing loop. */
+ while (filter->out_gen < filter->out_count)
+ {
+ /* Need to reload buffer? */
+ samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ;
+
+ if (samples_in_hand <= half_filter_chan_len)
+ { if ((psrc->error = prepare_data (filter, data, half_filter_chan_len)) != 0)
+ return psrc->error ;
+
+ samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ;
+ if (samples_in_hand <= half_filter_chan_len)
+ break ;
+ } ;
+
+ /* This is the termination condition. */
+ if (filter->b_real_end >= 0)
+ { if (filter->b_current + input_index + terminate >= filter->b_real_end)
+ break ;
+ } ;
+
+ if (filter->out_count > 0 && fabs (psrc->last_ratio - data->src_ratio) > 1e-10)
+ src_ratio = psrc->last_ratio + filter->out_gen * (data->src_ratio - psrc->last_ratio) / filter->out_count ;
+
+ float_increment = filter->index_inc * (src_ratio < 1.0 ? src_ratio : 1.0) ;
+ increment = double_to_fp (float_increment) ;
+
+ start_filter_index = double_to_fp (input_index * float_increment) ;
+
+ calc_output_stereo (filter, increment, start_filter_index, float_increment / filter->index_inc, data->data_out + filter->out_gen) ;
+ filter->out_gen += 2 ;
+
+ /* Figure out the next index. */
+ input_index += 1.0 / src_ratio ;
+ rem = fmod_one (input_index) ;
+
+ filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ;
+ input_index = rem ;
+ } ;
+
+ psrc->last_position = input_index ;
+
+ /* Save current ratio rather then target ratio. */
+ psrc->last_ratio = src_ratio ;
+
+ data->input_frames_used = filter->in_used / filter->channels ;
+ data->output_frames_gen = filter->out_gen / filter->channels ;
+
+ return SRC_ERR_NO_ERROR ;
+} /* sinc_stereo_vari_process */
+
+static inline void
+calc_output_quad (SINC_FILTER *filter, increment_t increment, increment_t start_filter_index, double scale, float * output)
+{ double fraction, left [4], right [4], icoeff ;
+ increment_t filter_index, max_filter_index ;
+ int data_index, coeff_count, indx ;
+
+ /* Convert input parameters into fixed point. */
+ max_filter_index = int_to_fp (filter->coeff_half_len) ;
+
+ /* First apply the left half of the filter. */
+ filter_index = start_filter_index ;
+ coeff_count = (max_filter_index - filter_index) / increment ;
+ filter_index = filter_index + coeff_count * increment ;
+ data_index = filter->b_current - filter->channels * coeff_count ;
+
+ left [0] = left [1] = left [2] = left [3] = 0.0 ;
+ do
+ { fraction = fp_to_double (filter_index) ;
+ indx = fp_to_int (filter_index) ;
+
+ icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ;
+
+ left [0] += icoeff * filter->buffer [data_index] ;
+ left [1] += icoeff * filter->buffer [data_index + 1] ;
+ left [2] += icoeff * filter->buffer [data_index + 2] ;
+ left [3] += icoeff * filter->buffer [data_index + 3] ;
+
+ filter_index -= increment ;
+ data_index = data_index + 4 ;
+ }
+ while (filter_index >= MAKE_INCREMENT_T (0)) ;
+
+ /* Now apply the right half of the filter. */
+ filter_index = increment - start_filter_index ;
+ coeff_count = (max_filter_index - filter_index) / increment ;
+ filter_index = filter_index + coeff_count * increment ;
+ data_index = filter->b_current + filter->channels * (1 + coeff_count) ;
+
+ right [0] = right [1] = right [2] = right [3] = 0.0 ;
+ do
+ { fraction = fp_to_double (filter_index) ;
+ indx = fp_to_int (filter_index) ;
+
+ icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ;
+
+ right [0] += icoeff * filter->buffer [data_index] ;
+ right [1] += icoeff * filter->buffer [data_index + 1] ;
+ right [2] += icoeff * filter->buffer [data_index + 2] ;
+ right [3] += icoeff * filter->buffer [data_index + 3] ;
+
+ filter_index -= increment ;
+ data_index = data_index - 4 ;
+ }
+ while (filter_index > MAKE_INCREMENT_T (0)) ;
+
+ output [0] = scale * (left [0] + right [0]) ;
+ output [1] = scale * (left [1] + right [1]) ;
+ output [2] = scale * (left [2] + right [2]) ;
+ output [3] = scale * (left [3] + right [3]) ;
+} /* calc_output_quad */
+
+static int
+sinc_quad_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data)
+{ SINC_FILTER *filter ;
+ double input_index, src_ratio, count, float_increment, terminate, rem ;
+ increment_t increment, start_filter_index ;
+ int half_filter_chan_len, samples_in_hand ;
+
+ if (psrc->private_data == NULL)
+ return SRC_ERR_NO_PRIVATE ;
+
+ filter = (SINC_FILTER*) psrc->private_data ;
+
+ /* If there is not a problem, this will be optimised out. */
+ if (sizeof (filter->buffer [0]) != sizeof (data->data_in [0]))
+ return SRC_ERR_SIZE_INCOMPATIBILITY ;
+
+ filter->in_count = data->input_frames * filter->channels ;
+ filter->out_count = data->output_frames * filter->channels ;
+ filter->in_used = filter->out_gen = 0 ;
+
+ src_ratio = psrc->last_ratio ;
+
+ if (is_bad_src_ratio (src_ratio))
+ return SRC_ERR_BAD_INTERNAL_STATE ;
+
+ /* Check the sample rate ratio wrt the buffer len. */
+ count = (filter->coeff_half_len + 2.0) / filter->index_inc ;
+ if (MIN (psrc->last_ratio, data->src_ratio) < 1.0)
+ count /= MIN (psrc->last_ratio, data->src_ratio) ;
+
+ /* Maximum coefficientson either side of center point. */
+ half_filter_chan_len = filter->channels * (lrint (count) + 1) ;
+
+ input_index = psrc->last_position ;
+ float_increment = filter->index_inc ;
+
+ rem = fmod_one (input_index) ;
+ filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ;
+ input_index = rem ;
+
+ terminate = 1.0 / src_ratio + 1e-20 ;
+
+ /* Main processing loop. */
+ while (filter->out_gen < filter->out_count)
+ {
+ /* Need to reload buffer? */
+ samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ;
+
+ if (samples_in_hand <= half_filter_chan_len)
+ { if ((psrc->error = prepare_data (filter, data, half_filter_chan_len)) != 0)
+ return psrc->error ;
+
+ samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ;
+ if (samples_in_hand <= half_filter_chan_len)
+ break ;
+ } ;
+
+ /* This is the termination condition. */
+ if (filter->b_real_end >= 0)
+ { if (filter->b_current + input_index + terminate >= filter->b_real_end)
+ break ;
+ } ;
+
+ if (filter->out_count > 0 && fabs (psrc->last_ratio - data->src_ratio) > 1e-10)
+ src_ratio = psrc->last_ratio + filter->out_gen * (data->src_ratio - psrc->last_ratio) / filter->out_count ;
+
+ float_increment = filter->index_inc * (src_ratio < 1.0 ? src_ratio : 1.0) ;
+ increment = double_to_fp (float_increment) ;
+
+ start_filter_index = double_to_fp (input_index * float_increment) ;
+
+ calc_output_quad (filter, increment, start_filter_index, float_increment / filter->index_inc, data->data_out + filter->out_gen) ;
+ filter->out_gen += 4 ;
+
+ /* Figure out the next index. */
+ input_index += 1.0 / src_ratio ;
+ rem = fmod_one (input_index) ;
+
+ filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ;
+ input_index = rem ;
+ } ;
+
+ psrc->last_position = input_index ;
+
+ /* Save current ratio rather then target ratio. */
+ psrc->last_ratio = src_ratio ;
+
+ data->input_frames_used = filter->in_used / filter->channels ;
+ data->output_frames_gen = filter->out_gen / filter->channels ;
+
+ return SRC_ERR_NO_ERROR ;
+} /* sinc_quad_vari_process */
+
+static inline void
+calc_output_hex (SINC_FILTER *filter, increment_t increment, increment_t start_filter_index, double scale, float * output)
+{ double fraction, left [6], right [6], icoeff ;
+ increment_t filter_index, max_filter_index ;
+ int data_index, coeff_count, indx ;
+
+ /* Convert input parameters into fixed point. */
+ max_filter_index = int_to_fp (filter->coeff_half_len) ;
+
+ /* First apply the left half of the filter. */
+ filter_index = start_filter_index ;
+ coeff_count = (max_filter_index - filter_index) / increment ;
+ filter_index = filter_index + coeff_count * increment ;
+ data_index = filter->b_current - filter->channels * coeff_count ;
+
+ left [0] = left [1] = left [2] = left [3] = left [4] = left [5] = 0.0 ;
+ do
+ { fraction = fp_to_double (filter_index) ;
+ indx = fp_to_int (filter_index) ;
+
+ icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ;
+
+ left [0] += icoeff * filter->buffer [data_index] ;
+ left [1] += icoeff * filter->buffer [data_index + 1] ;
+ left [2] += icoeff * filter->buffer [data_index + 2] ;
+ left [3] += icoeff * filter->buffer [data_index + 3] ;
+ left [4] += icoeff * filter->buffer [data_index + 4] ;
+ left [5] += icoeff * filter->buffer [data_index + 5] ;
+
+ filter_index -= increment ;
+ data_index = data_index + 6 ;
+ }
+ while (filter_index >= MAKE_INCREMENT_T (0)) ;
+
+ /* Now apply the right half of the filter. */
+ filter_index = increment - start_filter_index ;
+ coeff_count = (max_filter_index - filter_index) / increment ;
+ filter_index = filter_index + coeff_count * increment ;
+ data_index = filter->b_current + filter->channels * (1 + coeff_count) ;
+
+ right [0] = right [1] = right [2] = right [3] = right [4] = right [5] = 0.0 ;
+ do
+ { fraction = fp_to_double (filter_index) ;
+ indx = fp_to_int (filter_index) ;
+
+ icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ;
+
+ right [0] += icoeff * filter->buffer [data_index] ;
+ right [1] += icoeff * filter->buffer [data_index + 1] ;
+ right [2] += icoeff * filter->buffer [data_index + 2] ;
+ right [3] += icoeff * filter->buffer [data_index + 3] ;
+ right [4] += icoeff * filter->buffer [data_index + 4] ;
+ right [5] += icoeff * filter->buffer [data_index + 5] ;
+
+ filter_index -= increment ;
+ data_index = data_index - 6 ;
+ }
+ while (filter_index > MAKE_INCREMENT_T (0)) ;
+
+ output [0] = scale * (left [0] + right [0]) ;
+ output [1] = scale * (left [1] + right [1]) ;
+ output [2] = scale * (left [2] + right [2]) ;
+ output [3] = scale * (left [3] + right [3]) ;
+ output [4] = scale * (left [4] + right [4]) ;
+ output [5] = scale * (left [5] + right [5]) ;
+} /* calc_output_hex */
+
+static int
+sinc_hex_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data)
+{ SINC_FILTER *filter ;
+ double input_index, src_ratio, count, float_increment, terminate, rem ;
+ increment_t increment, start_filter_index ;
+ int half_filter_chan_len, samples_in_hand ;
+
+ if (psrc->private_data == NULL)
+ return SRC_ERR_NO_PRIVATE ;
+
+ filter = (SINC_FILTER*) psrc->private_data ;
+
+ /* If there is not a problem, this will be optimised out. */
+ if (sizeof (filter->buffer [0]) != sizeof (data->data_in [0]))
+ return SRC_ERR_SIZE_INCOMPATIBILITY ;
+
+ filter->in_count = data->input_frames * filter->channels ;
+ filter->out_count = data->output_frames * filter->channels ;
+ filter->in_used = filter->out_gen = 0 ;
+
+ src_ratio = psrc->last_ratio ;
+
+ if (is_bad_src_ratio (src_ratio))
+ return SRC_ERR_BAD_INTERNAL_STATE ;
+
+ /* Check the sample rate ratio wrt the buffer len. */
+ count = (filter->coeff_half_len + 2.0) / filter->index_inc ;
+ if (MIN (psrc->last_ratio, data->src_ratio) < 1.0)
+ count /= MIN (psrc->last_ratio, data->src_ratio) ;
+
+ /* Maximum coefficientson either side of center point. */
+ half_filter_chan_len = filter->channels * (lrint (count) + 1) ;
+
+ input_index = psrc->last_position ;
+ float_increment = filter->index_inc ;
+
+ rem = fmod_one (input_index) ;
+ filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ;
+ input_index = rem ;
+
+ terminate = 1.0 / src_ratio + 1e-20 ;
+
+ /* Main processing loop. */
+ while (filter->out_gen < filter->out_count)
+ {
+ /* Need to reload buffer? */
+ samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ;
+
+ if (samples_in_hand <= half_filter_chan_len)
+ { if ((psrc->error = prepare_data (filter, data, half_filter_chan_len)) != 0)
+ return psrc->error ;
+
+ samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ;
+ if (samples_in_hand <= half_filter_chan_len)
+ break ;
+ } ;
+
+ /* This is the termination condition. */
+ if (filter->b_real_end >= 0)
+ { if (filter->b_current + input_index + terminate >= filter->b_real_end)
+ break ;
+ } ;
+
+ if (filter->out_count > 0 && fabs (psrc->last_ratio - data->src_ratio) > 1e-10)
+ src_ratio = psrc->last_ratio + filter->out_gen * (data->src_ratio - psrc->last_ratio) / filter->out_count ;
+
+ float_increment = filter->index_inc * (src_ratio < 1.0 ? src_ratio : 1.0) ;
+ increment = double_to_fp (float_increment) ;
+
+ start_filter_index = double_to_fp (input_index * float_increment) ;
+
+ calc_output_hex (filter, increment, start_filter_index, float_increment / filter->index_inc, data->data_out + filter->out_gen) ;
+ filter->out_gen += 6 ;
+
+ /* Figure out the next index. */
+ input_index += 1.0 / src_ratio ;
+ rem = fmod_one (input_index) ;
+
+ filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ;
+ input_index = rem ;
+ } ;
+
+ psrc->last_position = input_index ;
+
+ /* Save current ratio rather then target ratio. */
+ psrc->last_ratio = src_ratio ;
+
+ data->input_frames_used = filter->in_used / filter->channels ;
+ data->output_frames_gen = filter->out_gen / filter->channels ;
+
+ return SRC_ERR_NO_ERROR ;
+} /* sinc_hex_vari_process */
+
+static inline void
+calc_output_multi (SINC_FILTER *filter, increment_t increment, increment_t start_filter_index, int channels, double scale, float * output)
+{ double fraction, icoeff ;
+ /* The following line is 1999 ISO Standard C. If your compiler complains, get a better compiler. */
+ double *left, *right ;
+ increment_t filter_index, max_filter_index ;
+ int data_index, coeff_count, indx, ch ;
+
+ left = filter->left_calc ;
+ right = filter->right_calc ;
+
+ /* Convert input parameters into fixed point. */
+ max_filter_index = int_to_fp (filter->coeff_half_len) ;
+
+ /* First apply the left half of the filter. */
+ filter_index = start_filter_index ;
+ coeff_count = (max_filter_index - filter_index) / increment ;
+ filter_index = filter_index + coeff_count * increment ;
+ data_index = filter->b_current - channels * coeff_count ;
+
+ memset (left, 0, sizeof (left [0]) * channels) ;
+
+ do
+ { fraction = fp_to_double (filter_index) ;
+ indx = fp_to_int (filter_index) ;
+
+ icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ;
+
+ /*
+ ** Duff's Device.
+ ** See : http://en.wikipedia.org/wiki/Duff's_device
+ */
+ ch = channels ;
+ do
+ {
+ switch (ch % 8)
+ { default :
+ ch -- ;
+ left [ch] += icoeff * filter->buffer [data_index + ch] ;
+ case 7 :
+ ch -- ;
+ left [ch] += icoeff * filter->buffer [data_index + ch] ;
+ case 6 :
+ ch -- ;
+ left [ch] += icoeff * filter->buffer [data_index + ch] ;
+ case 5 :
+ ch -- ;
+ left [ch] += icoeff * filter->buffer [data_index + ch] ;
+ case 4 :
+ ch -- ;
+ left [ch] += icoeff * filter->buffer [data_index + ch] ;
+ case 3 :
+ ch -- ;
+ left [ch] += icoeff * filter->buffer [data_index + ch] ;
+ case 2 :
+ ch -- ;
+ left [ch] += icoeff * filter->buffer [data_index + ch] ;
+ case 1 :
+ ch -- ;
+ left [ch] += icoeff * filter->buffer [data_index + ch] ;
+ } ;
+ }
+ while (ch > 0) ;
+
+ filter_index -= increment ;
+ data_index = data_index + channels ;
+ }
+ while (filter_index >= MAKE_INCREMENT_T (0)) ;
+
+ /* Now apply the right half of the filter. */
+ filter_index = increment - start_filter_index ;
+ coeff_count = (max_filter_index - filter_index) / increment ;
+ filter_index = filter_index + coeff_count * increment ;
+ data_index = filter->b_current + channels * (1 + coeff_count) ;
+
+ memset (right, 0, sizeof (right [0]) * channels) ;
+ do
+ { fraction = fp_to_double (filter_index) ;
+ indx = fp_to_int (filter_index) ;
+
+ icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ;
+
+ ch = channels ;
+ do
+ {
+ switch (ch % 8)
+ { default :
+ ch -- ;
+ right [ch] += icoeff * filter->buffer [data_index + ch] ;
+ case 7 :
+ ch -- ;
+ right [ch] += icoeff * filter->buffer [data_index + ch] ;
+ case 6 :
+ ch -- ;
+ right [ch] += icoeff * filter->buffer [data_index + ch] ;
+ case 5 :
+ ch -- ;
+ right [ch] += icoeff * filter->buffer [data_index + ch] ;
+ case 4 :
+ ch -- ;
+ right [ch] += icoeff * filter->buffer [data_index + ch] ;
+ case 3 :
+ ch -- ;
+ right [ch] += icoeff * filter->buffer [data_index + ch] ;
+ case 2 :
+ ch -- ;
+ right [ch] += icoeff * filter->buffer [data_index + ch] ;
+ case 1 :
+ ch -- ;
+ right [ch] += icoeff * filter->buffer [data_index + ch] ;
+ } ;
+ }
+ while (ch > 0) ;
+
+ filter_index -= increment ;
+ data_index = data_index - channels ;
+ }
+ while (filter_index > MAKE_INCREMENT_T (0)) ;
+
+ ch = channels ;
+ do
+ {
+ switch (ch % 8)
+ { default :
+ ch -- ;
+ output [ch] = scale * (left [ch] + right [ch]) ;
+ case 7 :
+ ch -- ;
+ output [ch] = scale * (left [ch] + right [ch]) ;
+ case 6 :
+ ch -- ;
+ output [ch] = scale * (left [ch] + right [ch]) ;
+ case 5 :
+ ch -- ;
+ output [ch] = scale * (left [ch] + right [ch]) ;
+ case 4 :
+ ch -- ;
+ output [ch] = scale * (left [ch] + right [ch]) ;
+ case 3 :
+ ch -- ;
+ output [ch] = scale * (left [ch] + right [ch]) ;
+ case 2 :
+ ch -- ;
+ output [ch] = scale * (left [ch] + right [ch]) ;
+ case 1 :
+ ch -- ;
+ output [ch] = scale * (left [ch] + right [ch]) ;
+ } ;
+ }
+ while (ch > 0) ;
+
+ return ;
+} /* calc_output_multi */
+
+static int
+sinc_multichan_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data)
+{ SINC_FILTER *filter ;
+ double input_index, src_ratio, count, float_increment, terminate, rem ;
+ increment_t increment, start_filter_index ;
+ int half_filter_chan_len, samples_in_hand ;
+
+ if (psrc->private_data == NULL)
+ return SRC_ERR_NO_PRIVATE ;
+
+ filter = (SINC_FILTER*) psrc->private_data ;
+
+ /* If there is not a problem, this will be optimised out. */
+ if (sizeof (filter->buffer [0]) != sizeof (data->data_in [0]))
+ return SRC_ERR_SIZE_INCOMPATIBILITY ;
+
+ filter->in_count = data->input_frames * filter->channels ;
+ filter->out_count = data->output_frames * filter->channels ;
+ filter->in_used = filter->out_gen = 0 ;
+
+ src_ratio = psrc->last_ratio ;
+
+ if (is_bad_src_ratio (src_ratio))
+ return SRC_ERR_BAD_INTERNAL_STATE ;
+
+ /* Check the sample rate ratio wrt the buffer len. */
+ count = (filter->coeff_half_len + 2.0) / filter->index_inc ;
+ if (MIN (psrc->last_ratio, data->src_ratio) < 1.0)
+ count /= MIN (psrc->last_ratio, data->src_ratio) ;
+
+ /* Maximum coefficientson either side of center point. */
+ half_filter_chan_len = filter->channels * (lrint (count) + 1) ;
+
+ input_index = psrc->last_position ;
+ float_increment = filter->index_inc ;
+
+ rem = fmod_one (input_index) ;
+ filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ;
+ input_index = rem ;
+
+ terminate = 1.0 / src_ratio + 1e-20 ;
+
+ /* Main processing loop. */
+ while (filter->out_gen < filter->out_count)
+ {
+ /* Need to reload buffer? */
+ samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ;
+
+ if (samples_in_hand <= half_filter_chan_len)
+ { if ((psrc->error = prepare_data (filter, data, half_filter_chan_len)) != 0)
+ return psrc->error ;
+
+ samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ;
+ if (samples_in_hand <= half_filter_chan_len)
+ break ;
+ } ;
+
+ /* This is the termination condition. */
+ if (filter->b_real_end >= 0)
+ { if (filter->b_current + input_index + terminate >= filter->b_real_end)
+ break ;
+ } ;
+
+ if (filter->out_count > 0 && fabs (psrc->last_ratio - data->src_ratio) > 1e-10)
+ src_ratio = psrc->last_ratio + filter->out_gen * (data->src_ratio - psrc->last_ratio) / filter->out_count ;
+
+ float_increment = filter->index_inc * (src_ratio < 1.0 ? src_ratio : 1.0) ;
+ increment = double_to_fp (float_increment) ;
+
+ start_filter_index = double_to_fp (input_index * float_increment) ;
+
+ calc_output_multi (filter, increment, start_filter_index, filter->channels, float_increment / filter->index_inc, data->data_out + filter->out_gen) ;
+ filter->out_gen += psrc->channels ;
+
+ /* Figure out the next index. */
+ input_index += 1.0 / src_ratio ;
+ rem = fmod_one (input_index) ;
+
+ filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ;
+ input_index = rem ;
+ } ;
+
+ psrc->last_position = input_index ;
+
+ /* Save current ratio rather then target ratio. */
+ psrc->last_ratio = src_ratio ;
+
+ data->input_frames_used = filter->in_used / filter->channels ;
+ data->output_frames_gen = filter->out_gen / filter->channels ;
+
+ return SRC_ERR_NO_ERROR ;
+} /* sinc_multichan_vari_process */
+
+/*----------------------------------------------------------------------------------------
+*/
+
+static int
+prepare_data (SINC_FILTER *filter, SRC_DATA *data, int half_filter_chan_len)
+{ int len = 0 ;
+
+ if (filter->b_real_end >= 0)
+ return 0 ; /* Should be terminating. Just return. */
+
+ if (filter->b_current == 0)
+ { /* Initial state. Set up zeros at the start of the buffer and
+ ** then load new data after that.
+ */
+ len = filter->b_len - 2 * half_filter_chan_len ;
+
+ filter->b_current = filter->b_end = half_filter_chan_len ;
+ }
+ else if (filter->b_end + half_filter_chan_len + filter->channels < filter->b_len)
+ { /* Load data at current end position. */
+ len = MAX (filter->b_len - filter->b_current - half_filter_chan_len, 0) ;
+ }
+ else
+ { /* Move data at end of buffer back to the start of the buffer. */
+ len = filter->b_end - filter->b_current ;
+ memmove (filter->buffer, filter->buffer + filter->b_current - half_filter_chan_len,
+ (half_filter_chan_len + len) * sizeof (filter->buffer [0])) ;
+
+ filter->b_current = half_filter_chan_len ;
+ filter->b_end = filter->b_current + len ;
+
+ /* Now load data at current end of buffer. */
+ len = MAX (filter->b_len - filter->b_current - half_filter_chan_len, 0) ;
+ } ;
+
+ len = MIN (filter->in_count - filter->in_used, len) ;
+ len -= (len % filter->channels) ;
+
+ if (len < 0 || filter->b_end + len > filter->b_len)
+ return SRC_ERR_SINC_PREPARE_DATA_BAD_LEN ;
+
+ memcpy (filter->buffer + filter->b_end, data->data_in + filter->in_used,
+ len * sizeof (filter->buffer [0])) ;
+
+ filter->b_end += len ;
+ filter->in_used += len ;
+
+ if (filter->in_used == filter->in_count &&
+ filter->b_end - filter->b_current < 2 * half_filter_chan_len && data->end_of_input)
+ { /* Handle the case where all data in the current buffer has been
+ ** consumed and this is the last buffer.
+ */
+
+ if (filter->b_len - filter->b_end < half_filter_chan_len + 5)
+ { /* If necessary, move data down to the start of the buffer. */
+ len = filter->b_end - filter->b_current ;
+ memmove (filter->buffer, filter->buffer + filter->b_current - half_filter_chan_len,
+ (half_filter_chan_len + len) * sizeof (filter->buffer [0])) ;
+
+ filter->b_current = half_filter_chan_len ;
+ filter->b_end = filter->b_current + len ;
+ } ;
+
+ filter->b_real_end = filter->b_end ;
+ len = half_filter_chan_len + 5 ;
+
+ if (len < 0 || filter->b_end + len > filter->b_len)
+ len = filter->b_len - filter->b_end ;
+
+ memset (filter->buffer + filter->b_end, 0, len * sizeof (filter->buffer [0])) ;
+ filter->b_end += len ;
+ } ;
+
+ return 0 ;
+} /* prepare_data */
+
+
projects / audio-libsamplerate.git / blobdiff