getid3_lib::BigEndian2Int

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Syntax Syntax

getid3_lib::BigEndian2Int( string $byteword, bool $synchsafe = false, bool $signed = false )

Parameters Parameters

$byteword

(string) (Required)

$synchsafe

(bool) (Optional)

Default value: false

$signed

(bool) (Optional)

Default value: false

Return Return

(int|float|false)

Source Source

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

		if ($bytewordlen == 0) {
			return false;
		}
		for ($i = 0; $i < $bytewordlen; $i++) {
			if ($synchsafe) { // disregard MSB, effectively 7-bit bytes
				//$intvalue = $intvalue | (ord($byteword{$i}) & 0x7F) << (($bytewordlen - 1 - $i) * 7); // faster, but runs into problems past 2^31 on 32-bit systems
				$intvalue += (ord($byteword[$i]) & 0x7F) * pow(2, ($bytewordlen - 1 - $i) * 7);
			} else {
				$intvalue += ord($byteword[$i]) * pow(256, ($bytewordlen - 1 - $i));
			}
		}
		if ($signed && !$synchsafe) {
			// synchsafe ints are not allowed to be signed
			if ($bytewordlen <= PHP_INT_SIZE) {
				$signMaskBit = 0x80 << (8 * ($bytewordlen - 1));
				if ($intvalue & $signMaskBit) {
					$intvalue = 0 - ($intvalue & ($signMaskBit - 1));
				}
			} else {
				throw new Exception('ERROR: Cannot have signed integers larger than '.(8 * PHP_INT_SIZE).'-bits ('.strlen($byteword).') in self::BigEndian2Int()');
			}
		}
		return self::CastAsInt($intvalue);
	}

	/**
	 * @param string $byteword

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