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Fix noises in rate exapnsion

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Fixed noises in rate exapnsion.
This commit is contained in:
Takashi Iwai 2005-03-24 20:28:56 +00:00
parent 7acb52ed84
commit e64cab565e
1 changed files with 43 additions and 21 deletions
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62
src/pcm/pcm_rate.c
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@ -81,6 +81,9 @@ struct _snd_pcm_rate {
unsigned int srate;
snd_pcm_channel_area_t *pareas; /* areas for splitted period (rate pcm) */
snd_pcm_channel_area_t *sareas; /* areas for splitted period (slave pcm) */
int16_t *old_sample;
int16_t *new_sample;
unsigned int pos;
};
static void snd_pcm_rate_expand(const snd_pcm_channel_area_t *dst_areas,
@ -102,6 +105,7 @@ static void snd_pcm_rate_expand(const snd_pcm_channel_area_t *dst_areas,
snd_pcm_uframes_t src_frames1;
snd_pcm_uframes_t dst_frames1;
int16_t sample = 0;
unsigned int pos;
for (channel = 0; channel < channels; ++channel) {
const snd_pcm_channel_area_t *src_area = &src_areas[channel];
@ -109,37 +113,31 @@ static void snd_pcm_rate_expand(const snd_pcm_channel_area_t *dst_areas,
const char *src;
char *dst;
int src_step, dst_step;
int16_t old_sample = 0;
int16_t new_sample = 0;
int16_t old_sample;
int16_t new_sample;
int old_weight, new_weight;
unsigned int pos = 0;
int init;
src = snd_pcm_channel_area_addr(src_area, src_offset);
dst = snd_pcm_channel_area_addr(dst_area, dst_offset);
src_step = snd_pcm_channel_area_step(src_area);
dst_step = snd_pcm_channel_area_step(dst_area);
src_frames1 = 0;
dst_frames1 = 0;
init = 1;
old_sample = rate->old_sample[channel];
new_sample = rate->new_sample[channel];
pos = rate->pos;
while (dst_frames1 < dst_frames) {
if (pos >= get_threshold) {
src += src_step;
src_frames1++;
if (src_frames1 < src_frames) {
pos -= get_threshold;
old_sample = new_sample;
if (src_frames1 < src_frames) {
goto *get;
#define GET16_END after_get
#include "plugin_ops.h"
#undef GET16_END
after_get:
new_sample = sample;
if (init) {
init = 0;
continue;
}
}
pos -= get_threshold;
}
new_weight = (pos << (16 - rate->pitch_shift)) / (get_threshold >> rate->pitch_shift);
old_weight = 0x10000 - new_weight;
sample = (old_sample * old_weight + new_sample * new_weight) >> 16;
@ -151,8 +149,15 @@ static void snd_pcm_rate_expand(const snd_pcm_channel_area_t *dst_areas,
dst += dst_step;
dst_frames1++;
pos += LINEAR_DIV;
if (pos >= get_threshold) {
src += src_step;
src_frames1++;
}
}
rate->old_sample[channel] = old_sample;
rate->new_sample[channel] = new_sample;
}
rate->pos = pos;
}
/* optimized version for S16 format */
@ -167,6 +172,7 @@ static void snd_pcm_rate_expand_s16(const snd_pcm_channel_area_t *dst_areas,
snd_pcm_uframes_t src_frames1;
snd_pcm_uframes_t dst_frames1;
unsigned int get_threshold = rate->pitch;
unsigned int pos;
for (channel = 0; channel < channels; ++channel) {
const snd_pcm_channel_area_t *src_area = &src_areas[channel];
@ -177,33 +183,37 @@ static void snd_pcm_rate_expand_s16(const snd_pcm_channel_area_t *dst_areas,
int16_t old_sample;
int16_t new_sample;
int old_weight, new_weight;
unsigned int pos;
src = snd_pcm_channel_area_addr(src_area, src_offset);
dst = snd_pcm_channel_area_addr(dst_area, dst_offset);
src_step = snd_pcm_channel_area_step(src_area) >> 1;
dst_step = snd_pcm_channel_area_step(dst_area) >> 1;
src_frames1 = 0;
dst_frames1 = 0;
old_sample = new_sample = *src;
pos = get_threshold;
old_sample = rate->old_sample[channel];
new_sample = rate->new_sample[channel];
pos = rate->pos;
while (dst_frames1 < dst_frames) {
if (pos >= get_threshold) {
pos -= get_threshold;
src += src_step;
src_frames1++;
if (src_frames1 < src_frames) {
old_sample = new_sample;
if (src_frames1 < src_frames)
new_sample = *src;
}
}
new_weight = (pos << (16 - rate->pitch_shift)) / (get_threshold >> rate->pitch_shift);
old_weight = 0x10000 - new_weight;
*dst = (old_sample * old_weight + new_sample * new_weight) >> 16;
dst += dst_step;
dst_frames1++;
pos += LINEAR_DIV;
if (pos >= get_threshold) {
src += src_step;
src_frames1++;
}
}
rate->old_sample[channel] = old_sample;
rate->new_sample[channel] = new_sample;
}
rate->pos = pos;
}
static void snd_pcm_rate_shrink(const snd_pcm_channel_area_t *dst_areas,
@ -577,6 +587,12 @@ static int snd_pcm_rate_hw_params(snd_pcm_t *pcm, snd_pcm_hw_params_t * params)
rate->pareas = malloc(2 * channels * sizeof(*rate->pareas));
if (rate->pareas == NULL)
return -ENOMEM;
free(rate->old_sample);
free(rate->new_sample);
rate->old_sample = malloc(sizeof(*rate->old_sample) * channels);
rate->new_sample = malloc(sizeof(*rate->new_sample) * channels);
if (rate->old_sample == NULL || rate->new_sample == NULL)
return -ENOMEM;
pwidth = snd_pcm_format_physical_width(pformat);
swidth = snd_pcm_format_physical_width(sformat);
rate->pareas[0].addr = malloc(((pwidth * channels * period_size) / 8) +
@ -607,6 +623,8 @@ static int snd_pcm_rate_hw_free(snd_pcm_t *pcm)
rate->pareas = NULL;
rate->sareas = NULL;
}
free(rate->old_sample);
free(rate->new_sample);
return snd_pcm_hw_free(rate->gen.slave);
}
@ -743,6 +761,10 @@ static int snd_pcm_rate_init(snd_pcm_t *pcm)
snd_pcm_rate_t *rate = pcm->private_data;
switch (rate->type) {
case RATE_TYPE_LINEAR:
/* for expand */
rate->pos = rate->pitch;
memset(rate->old_sample, 0, sizeof(*rate->old_sample) * pcm->channels);
memset(rate->new_sample, 0, sizeof(*rate->new_sample) * pcm->channels);
break;
default:
assert(0);