getid3_lib::Float2String

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Syntax Syntax

getid3_lib::Float2String( float $floatvalue, int $bits )

Parameters Parameters

$floatvalue

(Required)

$bits

(Required)

Return Return

(string|false)

Source Source

File: wp-includes/ID3/getid3.lib.php

	public static function Float2String($floatvalue, $bits) {
		$exponentbits = 0;
		$fractionbits = 0;
		switch ($bits) {
			case 32:
				$exponentbits = 8;
				$fractionbits = 23;
				break;

			case 64:
				$exponentbits = 11;
				$fractionbits = 52;
				break;

			default:
				return false;
		}
		if ($floatvalue >= 0) {
			$signbit = '0';
		} else {
			$signbit = '1';
		}
		$normalizedbinary  = self::NormalizeBinaryPoint(self::Float2BinaryDecimal($floatvalue), $fractionbits);
		$biasedexponent    = pow(2, $exponentbits - 1) - 1 + $normalizedbinary['exponent']; // (127 or 1023) +/- exponent
		$exponentbitstring = str_pad(decbin($biasedexponent), $exponentbits, '0', STR_PAD_LEFT);
		$fractionbitstring = str_pad(substr($normalizedbinary['normalized'], 2), $fractionbits, '0', STR_PAD_RIGHT);

		return self::BigEndian2String(self::Bin2Dec($signbit.$exponentbitstring.$fractionbitstring), $bits % 8, false);
	}

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