add pa_ prefix to all identifiers.

fix downsampling/resampling
add support for U8 samples


git-svn-id: file:///home/lennart/svn/public/pulseaudio/trunk@49 fefdeb5f-60dc-0310-8127-8f9354f1896f

src/sconv-s16le.c

@@ -0,0 +1,57 @@
+#include <assert.h>
+#include <inttypes.h>
+
+#include "endianmacros.h"
+#include "sconv.h"
+
+#ifndef INT16_FROM
+#define INT16_FROM INT16_FROM_LE
+#endif
+
+#ifndef INT16_TO
+#define INT16_TO INT16_TO_LE
+#endif
+
+void pa_sconv_s16le_to_float32(unsigned n, const void *a, unsigned an, float *b) {
+    const int16_t *ca = a;
+    assert(n && a && an && b);
+
+    for (; n > 0; n--) {
+        unsigned i;
+        float sum = 0;
+        
+        for (i = 0; i < an; i++) {
+            int16_t s = *(ca++);
+            sum += ((float) INT16_FROM(s))/0x7FFF;
+        }
+
+        if (sum > 1)
+            sum = 1;
+        if (sum < -1)
+            sum = -1;
+        
+        *(b++) = sum;
+    }
+}
+
+void pa_sconv_s16le_from_float32(unsigned n, const float *a, void *b, unsigned bn) {
+    int16_t *cb = b;
+    assert(n && a && b && bn);
+    
+    for (; n > 0; n--) {
+        unsigned i;
+        int16_t s;
+        float v = *(a++);
+
+        if (v > 1)
+            v = 1;
+        if (v < -1)
+            v = -1;
+
+        s = (int16_t) (v * 0x7FFF);
+        s = INT16_TO(s);
+
+        for (i = 0; i < bn; i++)
+            *(cb++) = s;
+    }
+}