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Next plugin fixes...

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This commit is contained in:
Jaroslav Kysela 1999-12-10 00:13:46 +00:00
parent 7da5d03952
commit d0fc70a1c7
2 changed files with 94 additions and 44 deletions
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110
src/pcm/plugin/rate.c
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@ -42,6 +42,7 @@ struct rate_private_data {
int dst_voices;
int src_rate;
int dst_rate;
int sample_size;
unsigned int pitch;
unsigned int pos;
signed short last_S1[MAX_VOICES];
@ -50,9 +51,9 @@ struct rate_private_data {
};
static void mix(struct rate_private_data *data, int voices,
signed short *src_ptr, int src_size,
signed short *dst_ptr, int dst_size)
static void mix16(struct rate_private_data *data, int voices,
signed short *src_ptr, int src_size,
signed short *dst_ptr, int dst_size)
{
unsigned int pos;
signed int val;
@ -79,7 +80,8 @@ static void mix(struct rate_private_data *data, int voices,
src += (pos >> SHIFT) * voices;
pos &= MASK;
S1 = S2;
S2 = *src;
if ((src - src_ptr) < src_size * voices)
S2 = *src;
}
val = S1 + ((S2 - S1) * (signed int)pos) / BITS;
if (val < -32768)
@ -92,8 +94,55 @@ static void mix(struct rate_private_data *data, int voices,
}
data->last_S1[voice] = S1;
data->last_S2[voice] = S2;
data->pos = pos;
}
}
static void mix8(struct rate_private_data *data, int voices,
unsigned char *src_ptr, int src_size,
unsigned char *dst_ptr, int dst_size)
{
unsigned int pos;
signed int val;
signed short S1, S2;
int voice;
unsigned char *src, *dst;
int size;
for (voice = 0; voice < voices; ++voice) {
pos = data->pos;
S1 = data->last_S1[voice];
S2 = data->last_S2[voice];
src = src_ptr + voice;
dst = dst_ptr + voice;
size = dst_size;
if (pos >> SHIFT) {
src += ((pos >> SHIFT) - 1) * voices;
pos &= MASK;
S1 = S2;
S2 = (*src << 8) ^ 0x8000;
}
while (size-- > 0) {
if (pos >> SHIFT) {
src += (pos >> SHIFT) * voices;
pos &= MASK;
S1 = S2;
if ((src - src_ptr) < src_size * voices)
S2 = (*src << 8) ^ 0x8000;
}
val = S1 + ((S2 - S1) * (signed int)pos) / BITS;
if (val < -32768)
val = -32768;
else if (val > 32767)
val = 32767;
*dst = (val >> 8) ^ 0x0080;
dst += voices;
pos += data->pitch;
}
data->last_S1[voice] = S1;
data->last_S2[voice] = S2;
data->pos = pos;
}
data->pos = pos;
}
static ssize_t rate_transfer(snd_pcm_plugin_t *plugin,
@ -110,10 +159,16 @@ 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, data->src_voices,
(signed short *)src_ptr, src_size / (data->src_voices * 2),
(signed short *)dst_ptr, dst_size / (data->dst_voices * 2));
return dst_size / (2 * data->src_voices) * (2 * data->src_voices);
if (data->sample_size == 2) {
mix16(data, data->src_voices,
(signed short *)src_ptr, src_size / (data->src_voices * 2),
(signed short *)dst_ptr, dst_size / (data->dst_voices * 2));
} else {
mix8(data, data->src_voices,
src_ptr, src_size / data->src_voices,
dst_ptr, dst_size / data->dst_voices);
}
return dst_size / (data->sample_size * data->src_voices) * (data->sample_size * data->src_voices);
}
static int rate_action(snd_pcm_plugin_t *plugin, snd_pcm_plugin_action_t action)
@ -147,14 +202,16 @@ static ssize_t rate_src_size(snd_pcm_plugin_t *plugin, size_t size)
return -EINVAL;
data = (struct rate_private_data *)snd_pcm_plugin_extra_data(plugin);
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;
data->old_src_size = size;
data->old_dst_size = res;
res = res / (data->src_voices*data->sample_size) * (data->src_voices*data->sample_size);
if (data->old_src_size > 0) {
if ((data->old_src_size % size) == 0) {
return (data->old_dst_size * data->old_src_size) / size;
} else if ((size % data->old_src_size) == 0) {
return (data->old_dst_size * size) / data->old_src_size;
}
}
data->old_src_size = size;
data->old_dst_size = res;
return res;
}
@ -167,14 +224,16 @@ static ssize_t rate_dst_size(snd_pcm_plugin_t *plugin, size_t size)
return -EINVAL;
data = (struct rate_private_data *)snd_pcm_plugin_extra_data(plugin);
res = (((size << SHIFT) + (data->pitch / 2)) / data->pitch);
res = res / (data->dst_voices*2) * (data->dst_voices*2);
/* Why this? */
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;
res = res / (data->dst_voices*data->sample_size) * (data->dst_voices*data->sample_size);
if (data->old_dst_size > 0) {
if ((data->old_dst_size % size) == 0) {
return (data->old_src_size * data->old_dst_size) / size;
} else if ((size % data->old_dst_size) == 0) {
return (data->old_src_size * size) / data->old_dst_size;
}
}
data->old_dst_size = size;
data->old_src_size = res;
return res;
}
@ -201,8 +260,8 @@ int snd_pcm_plugin_build_rate(snd_pcm_format_t *src_format,
if (dst_format->voices < 1 || dst_format->voices > MAX_VOICES)
return -EINVAL;
if (src_format->format != SND_PCM_SFMT_S16_LE ||
dst_format->format != SND_PCM_SFMT_S16_LE)
if (src_format->format != SND_PCM_SFMT_S16_LE &&
src_format->format != SND_PCM_SFMT_U8)
return -EINVAL;
if (src_format->rate == dst_format->rate)
return -EINVAL;
@ -211,6 +270,7 @@ int snd_pcm_plugin_build_rate(snd_pcm_format_t *src_format,
if (plugin == NULL)
return -ENOMEM;
data = (struct rate_private_data *)snd_pcm_plugin_extra_data(plugin);
data->sample_size = src_format->format == SND_PCM_SFMT_S16_LE ? 2 : 1;
data->src_voices = src_format->voices;
data->dst_voices = dst_format->voices;
data->src_rate = src_format->rate;