getid3_ac3::frameSizeLookup

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Syntax Syntax

getid3_ac3::frameSizeLookup( int $frmsizecod, int $fscod )

Parameters Parameters

$frmsizecod

(int) (Required)

$fscod

(int) (Required)

Return Return

(int|false)

Source Source

File: wp-includes/ID3/module.audio.ac3.php

	 *
	 * @return int|false
	 */
	public static function frameSizeLookup($frmsizecod, $fscod) {
		// LSB is whether padding is used or not
		$padding     = (bool) ($frmsizecod & 0x01);
		$framesizeid =        ($frmsizecod & 0x3E) >> 1;

		static $frameSizeLookup = array();
		if (empty($frameSizeLookup)) {
			$frameSizeLookup = array (
				0  => array( 128,  138,  192),  //  32 kbps
				1  => array( 160,  174,  240),  //  40 kbps
				2  => array( 192,  208,  288),  //  48 kbps
				3  => array( 224,  242,  336),  //  56 kbps
				4  => array( 256,  278,  384),  //  64 kbps
				5  => array( 320,  348,  480),  //  80 kbps
				6  => array( 384,  416,  576),  //  96 kbps
				7  => array( 448,  486,  672),  // 112 kbps
				8  => array( 512,  556,  768),  // 128 kbps
				9  => array( 640,  696,  960),  // 160 kbps
				10 => array( 768,  834, 1152),  // 192 kbps
				11 => array( 896,  974, 1344),  // 224 kbps
				12 => array(1024, 1114, 1536),  // 256 kbps
				13 => array(1280, 1392, 1920),  // 320 kbps
				14 => array(1536, 1670, 2304),  // 384 kbps
				15 => array(1792, 1950, 2688),  // 448 kbps
				16 => array(2048, 2228, 3072),  // 512 kbps
				17 => array(2304, 2506, 3456),  // 576 kbps
				18 => array(2560, 2786, 3840)   // 640 kbps
			);
		}
		$paddingBytes = 0;
		if (($fscod == 1) && $padding) {
			// frame lengths are padded by 1 word (16 bits) at 44100
			// (fscode==1) means 44100Hz (see sampleRateCodeLookup)
			$paddingBytes = 2;

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