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PCM plugin patches made by Abramo Bagnara.

Browse source 
Added new plugin - voice & balance.
This commit is contained in:
Jaroslav Kysela 1999-12-02 14:31:26 +00:00
parent 7167132eed
commit 78dc424b72
11 changed files with 580 additions and 260 deletions
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84
src/pcm/plugin/rate.c
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@ -48,6 +48,43 @@ struct rate_private_data {
ssize_t old_src_size, old_dst_size;
};
static void mix_mono(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 int L_S1, L_S2;
pos = data->pos;
L_S1 = data->last_L_S1;
L_S2 = data->last_L_S2;
if (pos >> SHIFT) {
src_ptr += ((pos >> SHIFT) - 1); pos &= MASK;
L_S1 = L_S2;
L_S2 = *src_ptr;
}
while (dst_size-- > 0) {
if (pos >> SHIFT) {
src_ptr += (pos >> SHIFT); pos &= MASK;
L_S1 = L_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;
pos += data->pitch;
}
data->last_L_S1 = L_S1;
data->last_L_S2 = L_S2;
data->pos = pos;
}
static void mix_stereo(struct rate_private_data *data,
signed short *src_ptr, int src_size,
signed short *dst_ptr, int dst_size)
@ -115,7 +152,12 @@ 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;
if (data->src_voices == 2) {
if (data->src_voices == 1) {
mix_mono(data, (signed short *)src_ptr, src_size / 2,
(signed short *)dst_ptr, dst_size / 2);
return (dst_size / 2) * 2;
}
else 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;
@ -152,7 +194,9 @@ static ssize_t rate_src_size(snd_pcm_plugin_t *plugin, size_t size)
if (!plugin || size <= 0)
return -EINVAL;
data = (struct rate_private_data *)snd_pcm_plugin_extra_data(plugin);
res = (((size * data->pitch) + (BITS/2)) >> SHIFT) & ~3;
res = (((size * data->pitch) + (BITS/2)) >> SHIFT);
res = res / (data->src_voices*2) * (data->src_voices*2);
/* Why this? */
if (size < 128*1024) {
if (data->old_src_size == size)
return data->old_dst_size;
@ -170,7 +214,9 @@ static ssize_t rate_dst_size(snd_pcm_plugin_t *plugin, size_t size)
if (!plugin || size <= 0)
return -EINVAL;
data = (struct rate_private_data *)snd_pcm_plugin_extra_data(plugin);
res = (((size << SHIFT) + (data->pitch / 2)) / data->pitch) & ~3;
res = (((size << SHIFT) + (data->pitch / 2)) / data->pitch);
res = res / (data->src_voices*2) * (data->src_voices*2);
/* Why this? */
if (size < 128*1024) {
if (data->old_dst_size == size)
return data->old_src_size;
@ -180,8 +226,8 @@ static ssize_t rate_dst_size(snd_pcm_plugin_t *plugin, size_t size)
return res;
}
int snd_pcm_plugin_build_rate(int src_format, int src_rate, int src_voices,
int dst_format, int dst_rate, int dst_voices,
int snd_pcm_plugin_build_rate(snd_pcm_format_t *src_format,
snd_pcm_format_t *dst_format,
snd_pcm_plugin_t **r_plugin)
{
struct rate_private_data *data;
@ -190,23 +236,33 @@ int snd_pcm_plugin_build_rate(int src_format, int src_rate, int src_voices,
if (!r_plugin)
return -EINVAL;
*r_plugin = NULL;
if (src_voices != 2 || dst_voices != 2)
if (src_format->interleave != dst_format->interleave)
return -EINVAL;
if (src_format != SND_PCM_SFMT_S16_LE ||
dst_format != SND_PCM_SFMT_S16_LE)
if (src_format->format != dst_format->format)
return -EINVAL;
if (src_rate == dst_rate)
if (!dst_format->interleave)
return -EINVAL;
if (src_format->voices != dst_format->voices)
return -EINVAL;
if (dst_format->voices != 1 && dst_format->voices != 2)
return -EINVAL;
if (src_format->format != SND_PCM_SFMT_S16_LE ||
dst_format->format != SND_PCM_SFMT_S16_LE)
return -EINVAL;
if (src_format->rate == dst_format->rate)
return -EINVAL;
plugin = snd_pcm_plugin_build("rate format conversion",
sizeof(struct rate_private_data));
if (plugin == NULL)
return -ENOMEM;
data = (struct rate_private_data *)snd_pcm_plugin_extra_data(plugin);
data->src_voices = src_voices;
data->dst_voices = dst_voices;
data->src_rate = src_rate;
data->dst_rate = dst_rate;
data->pitch = ((src_rate << SHIFT) + (dst_rate >> 1)) / dst_rate;
data->src_voices = src_format->voices;
data->dst_voices = dst_format->voices;
data->src_rate = src_format->rate;
data->dst_rate = dst_format->rate;
data->pitch = ((src_format->rate << SHIFT) + (dst_format->rate >> 1)) / dst_format->rate;
data->pos = 0;
data->last_L_S1 = data->last_R_S1 = 0;
data->last_L_S2 = data->last_R_S2 = 0;