-#endif /* PLATFORM_HPUX */
-
-#if defined(PLATFORM_UNIX) && !defined(AUDIO_STREAMING_DSP)
-
-/* these two are stolen from "sox"... :) */
-
-/*
-** This routine converts from linear to ulaw.
-**
-** Craig Reese: IDA/Supercomputing Research Center
-** Joe Campbell: Department of Defense
-** 29 September 1989
-**
-** References:
-** 1) CCITT Recommendation G.711 (very difficult to follow)
-** 2) "A New Digital Technique for Implementation of Any
-** Continuous PCM Companding Law," Villeret, Michel,
-** et al. 1973 IEEE Int. Conf. on Communications, Vol 1,
-** 1973, pg. 11.12-11.17
-** 3) MIL-STD-188-113,"Interoperability and Performance Standards
-** for Analog-to_Digital Conversion Techniques,"
-** 17 February 1987
-**
-** Input: Signed 16 bit linear sample
-** Output: 8 bit ulaw sample
-*/
-
-#define ZEROTRAP /* turn on the trap as per the MIL-STD */
-#define BIAS 0x84 /* define the add-in bias for 16 bit samples */
-#define CLIP 32635
-
-static unsigned char linear_to_ulaw(int sample)
-{
- static int exp_lut[256] =
- {
- 0,0,1,1,2,2,2,2,3,3,3,3,3,3,3,3,
- 4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
- 5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
- 5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
- 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
- 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
- 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
- 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
- 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
- 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
- 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
- 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
- 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
- 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
- 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
- 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7
- };
-
- int sign, exponent, mantissa;
- unsigned char ulawbyte;
-
- /* Get the sample into sign-magnitude. */
- sign = (sample >> 8) & 0x80; /* set aside the sign */
- if (sign != 0)
- sample = -sample; /* get magnitude */
- if (sample > CLIP)
- sample = CLIP; /* clip the magnitude */
-
- /* Convert from 16 bit linear to ulaw. */
- sample = sample + BIAS;
- exponent = exp_lut[( sample >> 7 ) & 0xFF];
- mantissa = ( sample >> ( exponent + 3 ) ) & 0x0F;
- ulawbyte = ~ ( sign | ( exponent << 4 ) | mantissa );
-#ifdef ZEROTRAP
- if (ulawbyte == 0)
- ulawbyte = 0x02; /* optional CCITT trap */
-#endif