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authorMax Kellermann <max@duempel.org>2008-09-29 17:25:45 +0200
committerMax Kellermann <max@duempel.org>2008-09-29 17:25:45 +0200
commitac6bc76cdb3e40841a8f7fcc0d55ea09eac10ef3 (patch)
tree7419bb37f5c851d5d1333a518ae3742ec8168fda /src
parentc85b570ad78a0185f45a08e63fefc667c4f056f7 (diff)
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pcm_utils: moved code to special 8/16 bit functions
Moved code into separate bit specific functions: - pcm_volumeChange() -> pcm_volume_change_X() - pcm_add() -> pcm_add_X() - pcm_convertTo16bit() -> pcm_convert_8_to_16()
Diffstat (limited to '')
-rw-r--r--src/pcm_utils.c165
1 files changed, 93 insertions, 72 deletions
diff --git a/src/pcm_utils.c b/src/pcm_utils.c
index 6e7156aea..a1f79f430 100644
--- a/src/pcm_utils.c
+++ b/src/pcm_utils.c
@@ -43,14 +43,38 @@ pcm_range(int32_t sample, unsigned bits)
return sample;
}
+static void
+pcm_volume_change_8(int8_t *buffer, unsigned num_samples,
+ unsigned volume)
+{
+ while (num_samples > 0) {
+ int32_t sample = *buffer;
+
+ sample = (sample * volume + pcm_dither() + 500) / 1000;
+
+ *buffer++ = pcm_range(sample, 8);
+ --num_samples;
+ }
+}
+
+static void
+pcm_volume_change_16(int16_t *buffer, unsigned num_samples,
+ unsigned volume)
+{
+ while (num_samples > 0) {
+ int32_t sample = *buffer;
+
+ sample = (sample * volume + pcm_dither() + 500) / 1000;
+
+ *buffer++ = pcm_range(sample, 16);
+ --num_samples;
+ }
+}
+
void pcm_volumeChange(char *buffer, int bufferSize,
const struct audio_format *format,
int volume)
{
- int32_t temp32;
- int8_t *buffer8 = (int8_t *) buffer;
- int16_t *buffer16 = (int16_t *) buffer;
-
if (volume >= 1000)
return;
@@ -60,74 +84,68 @@ void pcm_volumeChange(char *buffer, int bufferSize,
}
switch (format->bits) {
- case 16:
- while (bufferSize > 0) {
- temp32 = *buffer16;
- temp32 *= volume;
- temp32 += pcm_dither();
- temp32 += 500;
- temp32 /= 1000;
- *buffer16 = pcm_range(temp32, 16);
- buffer16++;
- bufferSize -= 2;
- }
- break;
case 8:
- while (bufferSize > 0) {
- temp32 = *buffer8;
- temp32 *= volume;
- temp32 += pcm_dither();
- temp32 += 500;
- temp32 /= 1000;
- *buffer8 = pcm_range(temp32, 8);
- buffer8++;
- bufferSize--;
- }
+ pcm_volume_change_8((int8_t *)buffer, bufferSize, volume);
break;
+
+ case 16:
+ pcm_volume_change_16((int16_t *)buffer, bufferSize / 2,
+ volume);
+ break;
+
default:
FATAL("%i bits not supported by pcm_volumeChange!\n",
format->bits);
}
}
+static void
+pcm_add_8(int8_t *buffer1, const int8_t *buffer2,
+ unsigned num_samples, int volume1, int volume2)
+{
+ while (num_samples > 0) {
+ int32_t sample1 = *buffer1;
+ int32_t sample2 = *buffer2++;
+
+ sample1 = ((sample1 * volume1 + sample2 * volume2) +
+ pcm_dither() + 500) / 1000;
+
+ *buffer1++ = pcm_range(sample1, 8);
+ --num_samples;
+ }
+}
+
+static void
+pcm_add_16(int16_t *buffer1, const int16_t *buffer2,
+ unsigned num_samples, int volume1, int volume2)
+{
+ while (num_samples > 0) {
+ int32_t sample1 = *buffer1;
+ int32_t sample2 = *buffer2++;
+
+ sample1 = ((sample1 * volume1 + sample2 * volume2) +
+ pcm_dither() + 500) / 1000;
+
+ *buffer1++ = pcm_range(sample1, 16);
+ --num_samples;
+ }
+}
+
static void pcm_add(char *buffer1, const char *buffer2, size_t size,
int vol1, int vol2,
const struct audio_format *format)
{
- int32_t temp32;
- int8_t *buffer8_1 = (int8_t *) buffer1;
- const int8_t *buffer8_2 = (const int8_t *) buffer2;
- int16_t *buffer16_1 = (int16_t *) buffer1;
- const int16_t *buffer16_2 = (const int16_t *) buffer2;
-
switch (format->bits) {
- case 16:
- while (size > 0) {
- temp32 =
- (vol1 * (*buffer16_1) +
- vol2 * (*buffer16_2));
- temp32 += pcm_dither();
- temp32 += 500;
- temp32 /= 1000;
- *buffer16_1 = pcm_range(temp32, 16);
- buffer16_1++;
- buffer16_2++;
- size -= 2;
- }
- break;
case 8:
- while (size > 0) {
- temp32 =
- (vol1 * (*buffer8_1) + vol2 * (*buffer8_2));
- temp32 += pcm_dither();
- temp32 += 500;
- temp32 /= 1000;
- *buffer8_1 = pcm_range(temp32, 8);
- buffer8_1++;
- buffer8_2++;
- size--;
- }
+ pcm_add_8((int8_t *)buffer1, (const int8_t *)buffer2,
+ size, vol1, vol2);
+ break;
+
+ case 16:
+ pcm_add_16((int16_t *)buffer1, (const int16_t *)buffer2,
+ size / 2, vol1, vol2);
break;
+
default:
FATAL("%i bits not supported by pcm_add!\n", format->bits);
}
@@ -357,41 +375,44 @@ static char *pcm_convertChannels(int8_t channels, const char *inBuffer,
return outBuffer;
}
+static void
+pcm_convert_8_to_16(int16_t *out, const int8_t *in,
+ unsigned num_samples)
+{
+ while (num_samples > 0) {
+ *out++ = *in++ << 8;
+ --num_samples;
+ }
+}
+
static const char *pcm_convertTo16bit(int8_t bits, const char *inBuffer,
size_t inSize, size_t *outSize)
{
static char *buf;
static size_t len;
- char *outBuffer = NULL;
- const int8_t *in;
- int16_t *out;
- size_t i;
+ unsigned num_samples;
switch (bits) {
case 8:
+ num_samples = inSize;
*outSize = inSize << 1;
if (*outSize > len) {
len = *outSize;
buf = xrealloc(buf, len);
}
- outBuffer = buf;
- in = (const int8_t *)inBuffer;
- out = (int16_t *)outBuffer;
- for (i = 0; i < inSize; i++)
- *out++ = (*in++) << 8;
+ pcm_convert_8_to_16((int16_t *)buf,
+ (const int8_t *)inBuffer,
+ num_samples);
+ return buf;
- break;
case 16:
*outSize = inSize;
return inBuffer;
- case 24:
- /* put dithering code from mp3_decode here */
- default:
- ERROR("only 8 or 16 bits are supported for conversion!\n");
}
- return outBuffer;
+ ERROR("only 8 or 16 bits are supported for conversion!\n");
+ return NULL;
}
/* outFormat bits must be 16 and channels must be 1 or 2! */