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    <p>16 bit PCM has a range - 32768 to 32767. So, multiply each of your PCM samples by (1.0f/32768.0f) into a new array of floats, and pass that to your resample. </p> <p>Going back to float after resampling, multiply by 32768.0, saturate (clip anything outside the range - 32768 to 32767), round (or dither as Björn mentioned) and then cast back to short. </p> <p>Test code that shows conversion forward and back using multiplies with no bit errors:</p> <pre><code>// PcmConvertTest.cpp : Defines the entry point for the console application. // #include &lt;assert.h&gt; #include &lt;string.h&gt; #include &lt;stdint.h&gt; #define SZ 65536 #define MAX(x,y) ((x)&gt;(y)) ? (x) : (y) #define MIN(x,y) ((x)&lt;(y)) ? (x) : (y) int main(int argc, char* argv[]) { int16_t *pIntBuf1 = new int16_t[SZ]; int16_t *pIntBuf2 = new int16_t[SZ]; float *pFloatBuf = new float[SZ]; // Create an initial short buffer for testing for( int i = 0; i &lt; SZ; i++) { pIntBuf1[i] = (int16_t)(-32768 + i); } // Convert the buffer to floats. (before resampling) const float div = (1.0f/32768.0f); for( int i = 0; i &lt; SZ; i++) { pFloatBuf[i] = div * (float)pIntBuf1[i]; } // Convert back to shorts const float mul = (32768.0f); for( int i = 0; i &lt; SZ; i++) { int32_t tmp = (int32_t)(mul * pFloatBuf[i]); tmp = MAX( tmp, -32768 ); // CLIP &lt; 32768 tmp = MIN( tmp, 32767 ); // CLIP &gt; 32767 pIntBuf2[i] = tmp; } // Check that the conversion went int16_t to float and back to int for every PCM value without any errors. assert( 0 == memcmp( pIntBuf1, pIntBuf2, sizeof(int16_t) * SZ) ); delete pIntBuf1; delete pIntBuf2; delete pFloatBuf; return 0; } </code></pre>
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