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Some small fixes...

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This commit is contained in:
Jaroslav Kysela 1999-11-24 18:17:00 +00:00
parent 875d195da0
commit 9433839ddd
1 changed files with 33 additions and 7 deletions
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40
src/pcm/plugin/rate.c
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@ -28,6 +28,10 @@
#include <byteswap.h>
#include "../pcm_local.h"
#define SHIFT 10
#define BITS (1<<SHIFT)
#define MASK (BITS-1)
/*
* Basic rate conversion plugin
*/
@ -38,6 +42,7 @@ struct rate_private_data {
unsigned int pitch;
unsigned int pos;
signed short last_L_S1, last_R_S1;
ssize_t old_src_size, old_dst_size;
};
static void mix(struct rate_private_data *data,
@ -53,16 +58,16 @@ static void mix(struct rate_private_data *data,
R_S1 = R_S2 = data->last_R_S1;
while (dst_size-- > 0) {
pos += data->pitch;
src_ptr += (pos >> 10) * 2; pos &= 0x3ff;
src_ptr += (pos >> SHIFT) * 2; pos &= MASK;
L_S2 = *src_ptr;
val = L_S1 + ((L_S2 + L_S1) * (signed int)pos) / 1024;
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) / 1024;
val = R_S1 + ((R_S2 + R_S1) * (signed int)pos) / BITS;
if (val < -32768)
val = -32768;
else if (val > 32767)
@ -71,7 +76,7 @@ static void mix(struct rate_private_data *data,
}
data->last_L_S1 = L_S2;
data->last_R_S1 = R_S2;
data->pos = pos & 0x3ff;
data->pos = pos;
}
static ssize_t rate_transfer(snd_pcm_plugin_t *plugin,
@ -96,21 +101,37 @@ static ssize_t rate_transfer(snd_pcm_plugin_t *plugin,
static ssize_t rate_src_size(snd_pcm_plugin_t *plugin, size_t size)
{
struct rate_private_data *data;
ssize_t res;
if (!plugin || size <= 0)
return -EINVAL;
data = (struct rate_private_data *)snd_pcm_plugin_extra_data(plugin);
return (((size * data->pitch) + 0x1ff) >> 10) & ~3;
res = (((size * data->pitch) + (BITS/2)) >> SHIFT) & ~3;
if (size < 128*1024) {
if (data->old_src_size == size)
return data->old_dst_size;
data->old_src_size = size;
data->old_dst_size = res;
}
return res;
}
static ssize_t rate_dst_size(snd_pcm_plugin_t *plugin, size_t size)
{
struct rate_private_data *data;
ssize_t res;
if (!plugin || size <= 0)
return -EINVAL;
data = (struct rate_private_data *)snd_pcm_plugin_extra_data(plugin);
return (((size << 10) + (data->pitch / 2)) / data->pitch) & ~3;
res = (((size << SHIFT) + (data->pitch / 2)) / data->pitch) & ~3;
if (size < 128*1024) {
if (data->old_dst_size == size)
return data->old_src_size;
data->old_dst_size = size;
data->old_src_size = res;
}
return res;
}
int snd_pcm_plugin_build_rate(int src_format, int src_rate, int src_voices,
@ -135,7 +156,12 @@ int snd_pcm_plugin_build_rate(int src_format, int src_rate, int src_voices,
if (plugin == NULL)
return -ENOMEM;
data = (struct rate_private_data *)snd_pcm_plugin_extra_data(plugin);
data->pitch = ((src_rate << 10) + (dst_rate >> 1)) / dst_rate;
data->src_rate = src_rate;
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->old_src_size = data->old_dst_size = 0;
plugin->transfer = rate_transfer;
plugin->src_size = rate_src_size;
plugin->dst_size = rate_dst_size;