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Steve Howes
17 lines
423 B
PHP
17 lines
423 B
PHP
<?php
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define ("SIGN_BIT" ,0x80);
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define ("QUANT_MASK" ,0xf);
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define ("BIAS" ,0x84);
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define ("SEG_SHIFT" ,4);
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define ("SEG_MASK" ,0x70);
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// Converts ulaw to 16 bit signed lin
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function ulaw2lin($u_val)
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{
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$u_val = ~$u_val;
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$t = (($u_val & QUANT_MASK) << 3) + BIAS;
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$t <<= ($u_val & SEG_MASK) >> SEG_SHIFT;
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return /*pack("s",*/intval(($u_val & SIGN_BIT) ? (BIAS - $t) : ($t - BIAS))/*)*/;
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}
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?>
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