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-rw-r--r--src/pcm_utils.c109
1 files changed, 99 insertions, 10 deletions
diff --git a/src/pcm_utils.c b/src/pcm_utils.c
index b56ed33ac..f6b308258 100644
--- a/src/pcm_utils.c
+++ b/src/pcm_utils.c
@@ -21,11 +21,16 @@
#include "mpd_types.h"
#include "log.h"
#include "utils.h"
+#include "conf.h"
#include <string.h>
#include <math.h>
#include <assert.h>
+#ifdef HAVE_LIBSAMPLERATE
+#include <samplerate.h>
+#endif
+
void pcm_volumeChange(char *buffer, int bufferSize, AudioFormat * format,
int volume)
{
@@ -46,6 +51,9 @@ void pcm_volumeChange(char *buffer, int bufferSize, AudioFormat * format,
while (bufferSize > 0) {
temp32 = *buffer16;
temp32 *= volume;
+ temp32 += rand() & 511;
+ temp32 -= rand() & 511;
+ temp32 += 500;
temp32 /= 1000;
*buffer16 = temp32 > 32767 ? 32767 :
(temp32 < -32768 ? -32768 : temp32);
@@ -57,6 +65,9 @@ void pcm_volumeChange(char *buffer, int bufferSize, AudioFormat * format,
while (bufferSize > 0) {
temp32 = *buffer8;
temp32 *= volume;
+ temp32 += rand() & 511;
+ temp32 -= rand() & 511;
+ temp32 += 500;
temp32 /= 1000;
*buffer8 = temp32 > 127 ? 127 :
(temp32 < -128 ? -128 : temp32);
@@ -86,7 +97,11 @@ static void pcm_add(char *buffer1, char *buffer2, size_t bufferSize1,
while (bufferSize1 > 0 && bufferSize2 > 0) {
temp32 =
(vol1 * (*buffer16_1) +
- vol2 * (*buffer16_2)) / 1000;
+ vol2 * (*buffer16_2));
+ temp32 += rand() & 511;
+ temp32 -= rand() & 511;
+ temp32 += 500;
+ temp32 /= 1000;
*buffer16_1 =
temp32 > 32767 ? 32767 : (temp32 <
-32768 ? -32768 : temp32);
@@ -101,7 +116,11 @@ static void pcm_add(char *buffer1, char *buffer2, size_t bufferSize1,
case 8:
while (bufferSize1 > 0 && bufferSize2 > 0) {
temp32 =
- (vol1 * (*buffer8_1) + vol2 * (*buffer8_2)) / 1000;
+ (vol1 * (*buffer8_1) + vol2 * (*buffer8_2));
+ temp32 += rand() & 511;
+ temp32 -= rand() & 511;
+ temp32 += 500;
+ temp32 /= 1000;
*buffer8_1 =
temp32 > 127 ? 127 : (temp32 <
-128 ? -128 : temp32);
@@ -133,6 +152,38 @@ void pcm_mix(char *buffer1, char *buffer2, size_t bufferSize1,
format);
}
+#ifdef HAVE_LIBSAMPLERATE
+static int pcm_getSamplerateConverter(void) {
+ const char *conf, *test;
+ int convalgo = SRC_SINC_FASTEST;
+ int newalgo;
+ size_t len;
+
+ conf = getConfigParamValue(CONF_SAMPLERATE_CONVERTER);
+ if(conf) {
+ newalgo = strtol(conf, (char **)&test, 10);
+ if(*test) {
+ len = strlen(conf);
+ for(newalgo = 0; ; newalgo++) {
+ test = src_get_name(newalgo);
+ if(!test)
+ break; /* FAIL */
+ if(!strncasecmp(test, conf, len)) {
+ convalgo = newalgo;
+ break;
+ }
+ }
+ } else {
+ if(src_get_name(newalgo))
+ convalgo = newalgo;
+ /* else FAIL */
+ }
+ }
+ DEBUG("Selecting samplerate converter '%s'\n", src_get_name(convalgo));
+ return convalgo;
+}
+#endif
+
/* outFormat bits must be 16 and channels must be 2! */
void pcm_convertAudioFormat(AudioFormat * inFormat, char *inBuffer, size_t
inSize, AudioFormat * outFormat, char *outBuffer)
@@ -234,6 +285,47 @@ void pcm_convertAudioFormat(AudioFormat * inFormat, char *inBuffer, size_t
if (inFormat->sampleRate == outFormat->sampleRate) {
memcpy(outBuffer, dataChannelConv, dataChannelLen);
} else {
+#ifdef HAVE_LIBSAMPLERATE
+ static SRC_STATE *state = NULL;
+ static SRC_DATA data;
+ int error;
+ static double ratio = 0;
+ double newratio;
+
+ if(!state) {
+ state = src_new(pcm_getSamplerateConverter(), outFormat->channels, &error);
+ if(!state) {
+ ERROR("Cannot create new samplerate state: %s\n", src_strerror(error));
+ exit(EXIT_FAILURE);
+ } else {
+ DEBUG("Samplerate converter initialized\n");
+ }
+ }
+
+ newratio = (double)outFormat->sampleRate / (double)inFormat->sampleRate;
+ if(newratio != ratio) {
+ src_set_ratio(state, ratio = newratio);
+ DEBUG("Setting samplerate conversion ratio to %.2lf\n", ratio);
+ }
+
+ data.input_frames = dataChannelLen / 2 / outFormat->channels;
+ data.output_frames = pcm_sizeOfOutputBufferForAudioFormatConversion(inFormat, dataChannelLen, outFormat) / 2 / outFormat->channels;
+ data.src_ratio = (double)data.output_frames / (double)data.input_frames;
+
+ float conversionInBuffer[data.input_frames * outFormat->channels];
+ float conversionOutBuffer[data.output_frames * outFormat->channels];
+ data.data_in = conversionInBuffer;
+ data.data_out = conversionOutBuffer;
+
+ src_short_to_float_array((short *)dataChannelConv, data.data_in, data.input_frames * outFormat->channels);
+ error = src_process(state, &data);
+ if(error) {
+ ERROR("Cannot process samples: %s\n", src_strerror(error));
+ exit(EXIT_FAILURE);
+ }
+
+ src_float_to_short_array(data.data_out, (short *)outBuffer, data.output_frames * outFormat->channels);
+#else
/* only works if outFormat is 16-bit stereo! */
/* resampling code blatantly ripped from ESD */
mpd_uint32 rd_dat = 0;
@@ -241,11 +333,7 @@ void pcm_convertAudioFormat(AudioFormat * inFormat, char *inBuffer, size_t
mpd_sint16 lsample, rsample;
mpd_sint16 *out = (mpd_sint16 *) outBuffer;
mpd_sint16 *in = (mpd_sint16 *) dataChannelConv;
- const int shift = sizeof(mpd_sint16) * outFormat->channels;
- mpd_uint32 nlen = (((dataChannelLen / shift) *
- (mpd_uint32) (outFormat->sampleRate)) /
- inFormat->sampleRate);
- nlen *= outFormat->channels;
+ mpd_uint32 nlen = pcm_sizeOfOutputBufferForAudioFormatConversion(inFormat, inSize, outFormat) / sizeof(mpd_sint16);
switch (outFormat->channels) {
case 1:
@@ -272,6 +360,7 @@ void pcm_convertAudioFormat(AudioFormat * inFormat, char *inBuffer, size_t
}
break;
}
+#endif
}
return;
@@ -306,9 +395,9 @@ size_t pcm_sizeOfOutputBufferForAudioFormatConversion(AudioFormat * inFormat,
}
}
- outSize = (((outSize / shift) * (mpd_uint32) (outFormat->sampleRate)) /
- inFormat->sampleRate);
-
+ outSize /= shift;
+ outSize = floor(0.5 + (double)outSize *
+ ((double)outFormat->sampleRate / (double)inFormat->sampleRate));
outSize *= shift;
return outSize;