getid3_quicktime::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_quicktime::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

Light

Touches nothing outside its own arguments.

Scaling

Scales with input

The body loops, so the work grows with how much data it finds.

Instructions

111–155

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 739.

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 · 2 distinct outcomes

One number would be a lie: the work depends on which branch runs. These are every distinct cost getid3_quicktime::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 · 9

• getid3_quicktime::fseek()
• getid3_lib::intValueSupported()
• getid3_quicktime::error()
• getid3_quicktime::fread()
• getid3_lib::BigEndian2Int()
• getid3_quicktime::QuicktimeParseAtom()
• getid3_quicktime::quicktime_time_to_sample_table()
• getid3_quicktime::quicktime_bookmark_time_scale()
• getid3_quicktime::warning()

Source code

View on Trac ↗View on GitHub ↗

52	public function Analyze() {53		$info = &$this->getid3->info;54 55		$this->metaDATAkey = 1;56		$info['fileformat'] = 'quicktime';57		$info['quicktime']['hinting']    = false;58		$info['quicktime']['controller'] = 'standard'; // may be overridden if 'ctyp' atom is present59 60		$this->fseek($info['avdataoffset']);61 62		$offset      = 0;63		$atomcounter = 0;64		$atom_data_read_buffer_size = $info['php_memory_limit'] ? round($info['php_memory_limit'] / 4) : $this->getid3->option_fread_buffer_size * 1024; // set read buffer to 25% of PHP memory limit (if one is specified), otherwise use option_fread_buffer_size [default: 32MB]65		while ($offset < $info['avdataend']) {66			if (!getid3_lib::intValueSupported($offset)) {67				$this->error('Unable to parse atom at offset '.$offset.' because beyond '.round(PHP_INT_MAX / 1073741824).'GB limit of PHP filesystem functions');68				break;69			}70			$this->fseek($offset);71			$AtomHeader = $this->fread(8);72 73			// https://github.com/JamesHeinrich/getID3/issues/38274			// Atom sizes are stored as 32-bit number in most cases, but sometimes (notably for "mdat")75			// a 64-bit value is required, in which case the normal 32-bit size field is set to 0x0000000176			// and the 64-bit "real" size value is the next 8 bytes.77			$atom_size_extended_bytes = 0;78			$atomsize = getid3_lib::BigEndian2Int(substr($AtomHeader, 0, 4));79			$atomname = substr($AtomHeader, 4, 4);80			if ($atomsize == 1) {81				$atom_size_extended_bytes = 8;82				$atomsize = getid3_lib::BigEndian2Int($this->fread($atom_size_extended_bytes));83			}84 85			if (($offset + $atomsize) > $info['avdataend']) {86				$info['quicktime'][$atomname]['name']   = $atomname;87				$info['quicktime'][$atomname]['size']   = $atomsize;88				$info['quicktime'][$atomname]['offset'] = $offset;89				$this->error('Atom at offset '.$offset.' claims to go beyond end-of-file (length: '.$atomsize.' bytes)');90				return false;91			}92			if ($atomsize == 0) {93				// Furthermore, for historical reasons the list of atoms is optionally94				// terminated by a 32-bit integer set to 0. If you are writing a program95				// to read user data atoms, you should allow for the terminating 0.96				$info['quicktime'][$atomname]['name']   = $atomname;97				$info['quicktime'][$atomname]['size']   = $atomsize;98				$info['quicktime'][$atomname]['offset'] = $offset;99				break;100			}101			$atomHierarchy = array();102			$parsedAtomData = $this->QuicktimeParseAtom($atomname, $atomsize, $this->fread(min($atomsize - $atom_size_extended_bytes, $atom_data_read_buffer_size)), $offset, $atomHierarchy, $this->ParseAllPossibleAtoms);103			$parsedAtomData['name']   = $atomname;104			$parsedAtomData['size']   = $atomsize;105			$parsedAtomData['offset'] = $offset;106			if ($atom_size_extended_bytes) {107				$parsedAtomData['xsize_bytes'] = $atom_size_extended_bytes;108			}109			if (in_array($atomname, array('uuid'))) {110				@$info['quicktime'][$atomname][] = $parsedAtomData;111			} else {112				$info['quicktime'][$atomname] = $parsedAtomData;113			}114 115			$offset += $atomsize;116			$atomcounter++;117		}118 119		if (!empty($info['avdataend_tmp'])) {120			// this value is assigned to a temp value and then erased because121			// otherwise any atoms beyond the 'mdat' atom would not get parsed122			$info['avdataend'] = $info['avdataend_tmp'];123			unset($info['avdataend_tmp']);124		}125 126		if (isset($info['quicktime']['comments']['chapters']) && is_array($info['quicktime']['comments']['chapters']) && (count($info['quicktime']['comments']['chapters']) > 0)) {127			$durations = $this->quicktime_time_to_sample_table($info);128			for ($i = 0; $i < count($info['quicktime']['comments']['chapters']); $i++) {129				$bookmark = array();130				$bookmark['title'] = $info['quicktime']['comments']['chapters'][$i];131				if (isset($durations[$i])) {

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-video.quicktime.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

Corrections

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