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Fixed many bugs..

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This commit is contained in:
Jaroslav Kysela 1999-11-25 10:15:28 +00:00
parent 8d94accc49
commit adb16d5236
1 changed files with 73 additions and 25 deletions
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90
src/pcm/plugin/rate.c
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@ -28,7 +28,7 @@
#include <byteswap.h>
#include "../pcm_local.h"
#define SHIFT 10
#define SHIFT 11
#define BITS (1<<SHIFT)
#define MASK (BITS-1)
@ -37,45 +37,67 @@
*/
struct rate_private_data {
unsigned int src_rate;
unsigned int dst_rate;
int src_voices;
int dst_voices;
int src_rate;
int dst_rate;
unsigned int pitch;
unsigned int pos;
signed short last_L_S1, last_R_S1;
signed short last_L_S2, last_R_S2;
ssize_t old_src_size, old_dst_size;
};
static void mix(struct rate_private_data *data,
static void mix_stereo(struct rate_private_data *data,
signed short *src_ptr, int src_size,
signed short *dst_ptr, int dst_size)
{
unsigned int pos;
signed int val;
signed short L_S1, R_S1, L_S2, R_S2;
signed int L_S1, R_S1, L_S2, R_S2;
pos = data->pos;
L_S1 = L_S2 = data->last_L_S1;
R_S1 = R_S2 = data->last_R_S1;
while (dst_size-- > 0) {
pos += data->pitch;
src_ptr += (pos >> SHIFT) * 2; pos &= MASK;
L_S1 = data->last_L_S1;
R_S1 = data->last_R_S1;
L_S2 = data->last_L_S2;
R_S2 = data->last_R_S2;
if (pos >> SHIFT) {
src_ptr += ((pos >> SHIFT) - 1) * 2; pos &= MASK;
L_S1 = L_S2;
R_S1 = R_S2;
L_S2 = *src_ptr;
val = L_S1 + ((L_S2 + L_S1) * (signed int)pos) / BITS;
if (val < -32768)
val = -32768;
else if (val > 32767)
val = 32767;
*dst_ptr++ = val;
R_S2 = *(src_ptr + 1);
val = R_S1 + ((R_S2 + R_S1) * (signed int)pos) / BITS;
}
while (dst_size-- > 0) {
if (pos >> SHIFT) {
src_ptr += (pos >> SHIFT) * 2; pos &= MASK;
L_S1 = L_S2;
R_S1 = R_S2;
L_S2 = *src_ptr;
R_S2 = *(src_ptr + 1);
}
val = L_S1 + ((L_S2 - L_S1) * (signed int)pos) / BITS;
if (val < -32768)
val = -32768;
else if (val > 32767)
val = 32767;
*dst_ptr++ = val;
// printf("L_S1 = %i, L_S2 = %i, pos = %i, val = %i\n", L_S1, L_S2, pos, val);
val = R_S1 + ((R_S2 - R_S1) * (signed int)pos) / BITS;
if (val < -32768)
val = -32768;
else if (val > 32767)
val = 32767;
*dst_ptr++ = val;
pos += data->pitch;
}
data->last_L_S1 = L_S2;
data->last_R_S1 = R_S2;
data->last_L_S1 = L_S1;
data->last_R_S1 = R_S1;
data->last_L_S2 = L_S2;
data->last_R_S2 = R_S2;
data->pos = pos;
}
@ -93,9 +115,33 @@ static ssize_t rate_transfer(snd_pcm_plugin_t *plugin,
data = (struct rate_private_data *)snd_pcm_plugin_extra_data(plugin);
if (data == NULL)
return -EINVAL;
mix(data, (signed short *)src_ptr, src_size / 4,
if (data->src_voices == 2) {
mix_stereo(data, (signed short *)src_ptr, src_size / 4,
(signed short *)dst_ptr, dst_size / 4);
return (dst_size / 4) * 4;
} else {
return -EINVAL;
}
}
static int rate_action(snd_pcm_plugin_t *plugin, snd_pcm_plugin_action_t action)
{
struct rate_private_data *data;
if (plugin == NULL)
return -EINVAL;
data = (struct rate_private_data *)snd_pcm_plugin_extra_data(plugin);
switch (action) {
case INIT:
case PREPARE:
case DRAIN:
case FLUSH:
data->pos = 0;
data->last_L_S1 = data->last_R_S1 = 0;
data->last_L_S2 = data->last_R_S2 = 0;
break;
}
return 0; /* silenty ignore other actions */
}
static ssize_t rate_src_size(snd_pcm_plugin_t *plugin, size_t size)
@ -160,11 +206,13 @@ int snd_pcm_plugin_build_rate(int src_format, int src_rate, int src_voices,
data->dst_rate = dst_rate;
data->pitch = ((src_rate << SHIFT) + (dst_rate >> 1)) / dst_rate;
data->pos = 0;
data->last_L_S1 = data->last_R_S1;
data->last_L_S1 = data->last_R_S1 = 0;
data->last_L_S2 = data->last_R_S2 = 0;
data->old_src_size = data->old_dst_size = 0;
plugin->transfer = rate_transfer;
plugin->src_size = rate_src_size;
plugin->dst_size = rate_dst_size;
plugin->action = rate_action;
*r_plugin = plugin;
return 0;
}