getid3_mp3::Analyze(): bool

Compatibility

Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.

Return value

bool

Performance profile

How much work a call to getid3_mp3::Analyze() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.

Cost class

Trivial

Touches nothing outside its own arguments.

Scaling

Constant

No loop in the body: the same number of instructions runs whatever you pass in.

Instructions

57–161

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 364.

Plugin surface

None

Nothing here hands control to plugin code.

Called by

0

Nothing in core calls this; the cost is only what you spend yourself.

What one call costs · 16 distinct outcomes

One number would be a lie: the work depends on which branch runs. These are every distinct cost getid3_mp3::Analyze() can have, taken from its control-flow graph on PHP 8.5.

This body has more branch combinations than are worth enumerating, so the table covers the outcomes found first rather than every one that exists.

Uses · 7

• getid3_mp3::getOnlyMPEGaudioInfo()
• getid3_mp3::error()
• getid3_mp3::getOnlyMPEGaudioInfoBruteForce()
• getid3_mp3::warning()
• getid3_mp3::fseek()
• getid3_mp3::fread()
• getid3_mp3::GuessEncoderOptions()

Source code

View on Trac ↗View on GitHub ↗

44	public function Analyze() {45		$info = &$this->getid3->info;46 47		$initialOffset = $info['avdataoffset'];48 49		if (!$this->getOnlyMPEGaudioInfo($info['avdataoffset'])) {50			if ($this->allow_bruteforce) {51				$this->error('Rescanning file in BruteForce mode');52				$this->getOnlyMPEGaudioInfoBruteForce();53			}54		}55 56 57		if (isset($info['mpeg']['audio']['bitrate_mode'])) {58			$info['audio']['bitrate_mode'] = strtolower($info['mpeg']['audio']['bitrate_mode']);59		}60 61		$CurrentDataLAMEversionString = null;62		if (((isset($info['id3v2']['headerlength']) && ($info['avdataoffset'] > $info['id3v2']['headerlength'])) || (!isset($info['id3v2']) && ($info['avdataoffset'] > 0) && ($info['avdataoffset'] != $initialOffset)))) {63 64			$synchoffsetwarning = 'Unknown data before synch ';65			if (isset($info['id3v2']['headerlength'])) {66				$synchoffsetwarning .= '(ID3v2 header ends at '.$info['id3v2']['headerlength'].', then '.($info['avdataoffset'] - $info['id3v2']['headerlength']).' bytes garbage, ';67			} elseif ($initialOffset > 0) {68				$synchoffsetwarning .= '(should be at '.$initialOffset.', ';69			} else {70				$synchoffsetwarning .= '(should be at beginning of file, ';71			}72			$synchoffsetwarning .= 'synch detected at '.$info['avdataoffset'].')';73			if (isset($info['audio']['bitrate_mode']) && ($info['audio']['bitrate_mode'] == 'cbr')) {74 75				if (!empty($info['id3v2']['headerlength']) && (($info['avdataoffset'] - $info['id3v2']['headerlength']) == $info['mpeg']['audio']['framelength'])) {76 77					$synchoffsetwarning .= '. This is a known problem with some versions of LAME (3.90-3.92) DLL in CBR mode.';78					$info['audio']['codec'] = 'LAME';79					$CurrentDataLAMEversionString = 'LAME3.';80 81				} elseif (empty($info['id3v2']['headerlength']) && ($info['avdataoffset'] == $info['mpeg']['audio']['framelength'])) {82 83					$synchoffsetwarning .= '. This is a known problem with some versions of LAME (3.90 - 3.92) DLL in CBR mode.';84					$info['audio']['codec'] = 'LAME';85					$CurrentDataLAMEversionString = 'LAME3.';86 87				}88 89			}90			$this->warning($synchoffsetwarning);91 92		}93 94		if (isset($info['mpeg']['audio']['LAME'])) {95			$info['audio']['codec'] = 'LAME';96			if (!empty($info['mpeg']['audio']['LAME']['long_version'])) {97				$info['audio']['encoder'] = rtrim($info['mpeg']['audio']['LAME']['long_version'], "\x00");98			} elseif (!empty($info['mpeg']['audio']['LAME']['short_version'])) {99				$info['audio']['encoder'] = rtrim($info['mpeg']['audio']['LAME']['short_version'], "\x00");100			}101		}102 103		$CurrentDataLAMEversionString = (!empty($CurrentDataLAMEversionString) ? $CurrentDataLAMEversionString : (isset($info['audio']['encoder']) ? $info['audio']['encoder'] : ''));104		if (!empty($CurrentDataLAMEversionString) && (substr($CurrentDataLAMEversionString, 0, 6) == 'LAME3.') && !preg_match('[0-9\)]', substr($CurrentDataLAMEversionString, -1))) {105			// a version number of LAME that does not end with a number like "LAME3.92"106			// or with a closing parenthesis like "LAME3.88 (alpha)"107			// or a version of LAME with the LAMEtag-not-filled-in-DLL-mode bug (3.90-3.92)108 109			// not sure what the actual last frame length will be, but will be less than or equal to 1441110			$PossiblyLongerLAMEversion_FrameLength = 1441;111 112			// Not sure what version of LAME this is - look in padding of last frame for longer version string113			$PossibleLAMEversionStringOffset = $info['avdataend'] - $PossiblyLongerLAMEversion_FrameLength;114			$this->fseek($PossibleLAMEversionStringOffset);115			$PossiblyLongerLAMEversion_Data = $this->fread($PossiblyLongerLAMEversion_FrameLength);116			switch (substr($CurrentDataLAMEversionString, -1)) {117				case 'a':118				case 'b':119					// "LAME3.94a" will have a longer version string of "LAME3.94 (alpha)" for example120					// need to trim off "a" to match longer string121					$CurrentDataLAMEversionString = substr($CurrentDataLAMEversionString, 0, -1);122					break;123			}

Changelog

Unchanged from 6.7.7 through 7.1.0.

1. 6.7.7
2. 6.8.8
3. 6.9.7
4. 7.0.4
5. 7.1.0

Signature, return type and hooks compared across 5 parsed releases.

About this page

Parsed data

Generated from the wordpress-develop 7.1.0 tag, from src/wp-includes/ID3/module.audio.mp3.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

Corrections

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