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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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64
src/pcm/pcm_rate.c
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@ -81,6 +81,9 @@ struct _snd_pcm_rate {
unsigned int srate; unsigned int srate;
snd_pcm_channel_area_t *pareas; /* areas for splitted period (rate pcm) */ snd_pcm_channel_area_t *pareas; /* areas for splitted period (rate pcm) */
snd_pcm_channel_area_t *sareas; /* areas for splitted period (slave 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, 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 src_frames1;
snd_pcm_uframes_t dst_frames1; snd_pcm_uframes_t dst_frames1;
int16_t sample = 0; int16_t sample = 0;
unsigned int pos;
for (channel = 0; channel < channels; ++channel) { for (channel = 0; channel < channels; ++channel) {
const snd_pcm_channel_area_t *src_area = &src_areas[channel]; const snd_pcm_channel_area_t *src_area = &src_areas[channel];
@ -109,36 +113,30 @@ static void snd_pcm_rate_expand(const snd_pcm_channel_area_t *dst_areas,
const char *src; const char *src;
char *dst; char *dst;
int src_step, dst_step; int src_step, dst_step;
int16_t old_sample = 0; int16_t old_sample;
int16_t new_sample = 0; int16_t new_sample;
int old_weight, new_weight; int old_weight, new_weight;
unsigned int pos = 0;
int init;
src = snd_pcm_channel_area_addr(src_area, src_offset); src = snd_pcm_channel_area_addr(src_area, src_offset);
dst = snd_pcm_channel_area_addr(dst_area, dst_offset); dst = snd_pcm_channel_area_addr(dst_area, dst_offset);
src_step = snd_pcm_channel_area_step(src_area); src_step = snd_pcm_channel_area_step(src_area);
dst_step = snd_pcm_channel_area_step(dst_area); dst_step = snd_pcm_channel_area_step(dst_area);
src_frames1 = 0; src_frames1 = 0;
dst_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) { while (dst_frames1 < dst_frames) {
if (pos >= get_threshold) { if (pos >= get_threshold) {
src += src_step; pos -= get_threshold;
src_frames1++; old_sample = new_sample;
if (src_frames1 < src_frames) { if (src_frames1 < src_frames) {
old_sample = new_sample;
goto *get; goto *get;
#define GET16_END after_get #define GET16_END after_get
#include "plugin_ops.h" #include "plugin_ops.h"
#undef GET16_END #undef GET16_END
after_get: after_get:
new_sample = sample; new_sample = sample;
if (init) {
init = 0;
continue;
}
} }
pos -= get_threshold;
} }
new_weight = (pos << (16 - rate->pitch_shift)) / (get_threshold >> rate->pitch_shift); new_weight = (pos << (16 - rate->pitch_shift)) / (get_threshold >> rate->pitch_shift);
old_weight = 0x10000 - new_weight; old_weight = 0x10000 - new_weight;
@ -151,8 +149,15 @@ static void snd_pcm_rate_expand(const snd_pcm_channel_area_t *dst_areas,
dst += dst_step; dst += dst_step;
dst_frames1++; dst_frames1++;
pos += LINEAR_DIV; 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 */ /* 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 src_frames1;
snd_pcm_uframes_t dst_frames1; snd_pcm_uframes_t dst_frames1;
unsigned int get_threshold = rate->pitch; unsigned int get_threshold = rate->pitch;
unsigned int pos;
for (channel = 0; channel < channels; ++channel) { for (channel = 0; channel < channels; ++channel) {
const snd_pcm_channel_area_t *src_area = &src_areas[channel]; const snd_pcm_channel_area_t *src_area = &src_areas[channel];
@ -177,24 +183,21 @@ static void snd_pcm_rate_expand_s16(const snd_pcm_channel_area_t *dst_areas,
int16_t old_sample; int16_t old_sample;
int16_t new_sample; int16_t new_sample;
int old_weight, new_weight; int old_weight, new_weight;
unsigned int pos;
src = snd_pcm_channel_area_addr(src_area, src_offset); src = snd_pcm_channel_area_addr(src_area, src_offset);
dst = snd_pcm_channel_area_addr(dst_area, dst_offset); dst = snd_pcm_channel_area_addr(dst_area, dst_offset);
src_step = snd_pcm_channel_area_step(src_area) >> 1; src_step = snd_pcm_channel_area_step(src_area) >> 1;
dst_step = snd_pcm_channel_area_step(dst_area) >> 1; dst_step = snd_pcm_channel_area_step(dst_area) >> 1;
src_frames1 = 0; src_frames1 = 0;
dst_frames1 = 0; dst_frames1 = 0;
old_sample = new_sample = *src; old_sample = rate->old_sample[channel];
pos = get_threshold; new_sample = rate->new_sample[channel];
pos = rate->pos;
while (dst_frames1 < dst_frames) { while (dst_frames1 < dst_frames) {
if (pos >= get_threshold) { if (pos >= get_threshold) {
pos -= get_threshold; pos -= get_threshold;
src += src_step; old_sample = new_sample;
src_frames1++; if (src_frames1 < src_frames)
if (src_frames1 < src_frames) {
old_sample = new_sample;
new_sample = *src; new_sample = *src;
}
} }
new_weight = (pos << (16 - rate->pitch_shift)) / (get_threshold >> rate->pitch_shift); new_weight = (pos << (16 - rate->pitch_shift)) / (get_threshold >> rate->pitch_shift);
old_weight = 0x10000 - new_weight; old_weight = 0x10000 - new_weight;
@ -202,8 +205,15 @@ static void snd_pcm_rate_expand_s16(const snd_pcm_channel_area_t *dst_areas,
dst += dst_step; dst += dst_step;
dst_frames1++; dst_frames1++;
pos += LINEAR_DIV; 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, 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)); rate->pareas = malloc(2 * channels * sizeof(*rate->pareas));
if (rate->pareas == NULL) if (rate->pareas == NULL)
return -ENOMEM; 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); pwidth = snd_pcm_format_physical_width(pformat);
swidth = snd_pcm_format_physical_width(sformat); swidth = snd_pcm_format_physical_width(sformat);
rate->pareas[0].addr = malloc(((pwidth * channels * period_size) / 8) + 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->pareas = NULL;
rate->sareas = NULL; rate->sareas = NULL;
} }
free(rate->old_sample);
free(rate->new_sample);
return snd_pcm_hw_free(rate->gen.slave); 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; snd_pcm_rate_t *rate = pcm->private_data;
switch (rate->type) { switch (rate->type) {
case RATE_TYPE_LINEAR: 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; break;
default: default:
assert(0); assert(0);