Class for reading xmp data containing properties relevant to images, and spitting out an array that FormatExif accepts. More...

Public Member Functions
	__construct ()
	Constructor.
	__destruct ()
	Destroy the xml parser.
	char ($parser, $data)
	Character data handler Called whenever character data is found in the xmp document.
	endElement ($parser, $elm)
	Handler for hitting a closing element.
	getResults ()
	Get the result array.
	parse ($content, $allOfIt=true, $reset=false)
	Main function to call to parse XMP.
	parseExtended ($content)
	Entry point for XMPExtended blocks in jpeg files.
	startElement ($parser, $elm, $attribs)
	Hits an opening element.
Public Attributes
const	MODE_ALT = 15
const	MODE_BAG = 13
const	MODE_BAGSTRUCT = 16
const	MODE_IGNORE = 1
const	MODE_INITIAL = 0
	These are various mode constants.
const	MODE_LANG = 14
const	MODE_LI = 2
const	MODE_LI_LANG = 3
const	MODE_QDESC = 4
const	MODE_SEQ = 12
const	MODE_SIMPLE = 10
const	MODE_STRUCT = 11
const	NS_RDF = 'http://www.w3.org/1999/02/22-rdf-syntax-ns#'
const	NS_XML = 'http://www.w3.org/XML/1998/namespace'
Protected Attributes
	$items
Private Member Functions
	doAttribs ($attribs)
	Process attributes.
	endElementModeIgnore ($elm)
	When we hit a closing element in MODE_IGNORE Check to see if this is the element we started to ignore, in which case we get out of MODE_IGNORE.
	endElementModeLi ($elm)
	Hit a closing element in MODE_LI (either rdf:Seq, or rdf:Bag ) Add information about what type of element this is.
	endElementModeQDesc ($elm)
	End element while in MODE_QDESC mostly when ending an element when we have a simple value that has qualifiers.
	endElementModeSimple ($elm)
	Hit a closing element when in MODE_SIMPLE.
	endElementNested ($elm)
	Hit a closing element in MODE_STRUCT, MODE_SEQ, MODE_BAG generally means we've finished processing a nested structure.
	resetXMLParser ()
	Main use is if a single item has multiple xmp documents describing it.
	saveValue ($ns, $tag, $val)
	Given an extracted value, save it to results array.
	startElementModeBag ($elm)
	Start element in MODE_BAG (unordered array) this should always be <rdf:Bag>
	startElementModeIgnore ($elm)
	Hit an opening element while in MODE_IGNORE.
	startElementModeInitial ($ns, $tag, $attribs)
	Starting an element when in MODE_INITIAL This usually happens when we hit an element inside the outer rdf:Description.
	startElementModeLang ($elm)
	Start element in MODE_LANG (language alternative) this should always be <rdf:Alt>
	startElementModeLi ($elm, $attribs)
	opening element in MODE_LI process elements of arrays.
	startElementModeLiLang ($elm, $attribs)
	Opening element in MODE_LI_LANG.
	startElementModeQDesc ($elm)
	Start an element when in MODE_QDESC.
	startElementModeSeq ($elm)
	Start element in MODE_SEQ (ordered array) this should always be <rdf:Seq>
	startElementModeSimple ($elm, $attribs)
	Handle an opening element when in MODE_SIMPLE.
	startElementModeStruct ($ns, $tag, $attribs)
	Hit an opening element when in a Struct (MODE_STRUCT) This is generally for fields of a compound property.
Private Attributes
	$ancestorStruct = false
	$charContent = false
	$charset = false
	$curItem = array()
	$extendedXMPOffset = 0
	$itemLang = false
	$mode = array()
	$processingArray = false
	$results = array()
	$xmlParser

Detailed Description

Class for reading xmp data containing properties relevant to images, and spitting out an array that FormatExif accepts.

Note, this is not meant to recognize every possible thing you can encode in XMP. It should recognize all the properties we want. For example it doesn't have support for structures with multiple nesting levels, as none of the properties we're supporting use that feature. If it comes across properties it doesn't recognize, it should ignore them.

The public methods one would call in this class are

parse( $content ) Reads in xmp content. Can potentially be called multiple times with partial data each time.
parseExtended( $content ) Reads XMPExtended blocks (jpeg files only).
getResults Outputs a results array.

Note XMP kind of looks like rdf. They are not the same thing - XMP is encoded as a specific subset of rdf. This class can read XMP. It cannot read rdf.

Definition at line 49 of file XMP.php.

Constructor & Destructor Documentation

XMPReader::__construct ( )

Constructor.

Primary job is to initialize the XMLParser

Definition at line 98 of file XMP.php.

References XMPInfo\getItems(), and resetXMLParser().

XMPReader::__destruct ( )

Destroy the xml parser.

Not sure if this is actually needed.

Definition at line 136 of file XMP.php.

Member Function Documentation

XMPReader::char	(	$	parser,
		$	data
	)

Character data handler Called whenever character data is found in the xmp document.

does nothing if we're in MODE_IGNORE or if the data is whitespace throws an error if we're not in MODE_SIMPLE (as we're not allowed to have character data in the other modes).

As an example, this happens when we encounter XMP like: <exif:DigitalZoomRatio>0/10</exif:DigitalZoomRatio> and are processing the 0/10 bit.

Parameters:

	$parser	XMLParser reference to the xml parser
string	$data	Character data

Exceptions:

MWException on invalid data

Definition at line 383 of file XMP.php.

Referenced by doAttribs().

XMPReader::doAttribs ( $ attribs ) [private]

Process attributes.

Simple values can be stored as either a tag or attribute

Often the initial "<rdf:Description>" tag just has all the simple properties as attributes.

Example:

 <rdf:Description rdf:about="" xmlns:exif="http://ns.adobe.com/exif/1.0/" exif:DigitalZoomRatio="0/10">

Parameters:

array $attribs attribute=>value array.

Exceptions:

MWException

Definition at line 1115 of file XMP.php.

References $attribs, $name, as, char(), list, MODE_QDESC, saveValue(), and wfDebugLog().

Referenced by startElementModeInitial(), startElementModeLi(), and startElementModeStruct().

XMPReader::endElement	(	$	parser,
		$	elm
	)

Handler for hitting a closing element.

generally just calls a helper function depending on what mode we're in.

Ignores the outer wrapping elements that are optional in xmp and have no meaning.

Parameters:

	$parser	XMLParser
string	$elm	namespace . ' ' . element name

Exceptions:

MWException

Definition at line 608 of file XMP.php.

References endElementModeIgnore(), endElementModeLi(), endElementModeQDesc(), endElementModeSimple(), endElementNested(), and wfDebugLog().

XMPReader::endElementModeIgnore ( $ elm ) [private]

When we hit a closing element in MODE_IGNORE Check to see if this is the element we started to ignore, in which case we get out of MODE_IGNORE.

Parameters:

string $elm Namespace of element followed by a space and then tag name of element.

Definition at line 419 of file XMP.php.

Referenced by endElement().

XMPReader::endElementModeLi ( $ elm ) [private]

Hit a closing element in MODE_LI (either rdf:Seq, or rdf:Bag ) Add information about what type of element this is.

Note we still have to hit the outer "</property>"

For example, when processing:

 {,xml}
 <exif:ISOSpeedRatings> <rdf:Seq> <rdf:li>64</rdf:li>
   </rdf:Seq> </exif:ISOSpeedRatings>

This method is called when we hit the "</rdf:Seq>". (For comparison, we call endElementModeSimple when we hit the "</rdf:li>")

Parameters:

string $elm namespace . ' ' . element name

Exceptions:

MWException

Definition at line 544 of file XMP.php.

References list, and wfDebugLog().

Referenced by endElement().

XMPReader::endElementModeQDesc ( $ elm ) [private]

End element while in MODE_QDESC mostly when ending an element when we have a simple value that has qualifiers.

Qualifiers aren't all that common, and we don't do anything with them.

Parameters:

string $elm namespace and element

Definition at line 583 of file XMP.php.

References list, and saveValue().

Referenced by endElement().

XMPReader::endElementModeSimple ( $ elm ) [private]

Hit a closing element when in MODE_SIMPLE.

This generally means that we finished processing a property value, and now have to save the result to the results array

For example, when processing: <exif:DigitalZoomRatio>0/10</exif:DigitalZoomRatio> this deals with when we hit </exif:DigitalZoomRatio>.

Or it could be if we hit the end element of a property of a compound data structure (like a member of an array).

Parameters:

string $elm namespace, space, and tag name.

Definition at line 441 of file XMP.php.

References list, and saveValue().

Referenced by endElement().

XMPReader::endElementNested ( $ elm ) [private]

Hit a closing element in MODE_STRUCT, MODE_SEQ, MODE_BAG generally means we've finished processing a nested structure.

resets some internal variables to indicate that.

Note this means we hit the closing element not the "</rdf:Seq>".

For example, when processing:

 {,xml}
 <exif:ISOSpeedRatings> <rdf:Seq> <rdf:li>64</rdf:li>
   </rdf:Seq> </exif:ISOSpeedRatings>

This method is called when we hit the "</exif:ISOSpeedRatings>" tag.

Parameters:

string $elm namespace . space . tag name.

Exceptions:

MWException

Definition at line 477 of file XMP.php.

References array(), list, and wfDebugLog().

Referenced by endElement().

XMPReader::getResults ( )

Get the result array.

Do some post-processing before returning the array, and transform any metadata that is special-cased.

Returns:: Array array of results as an array of arrays suitable for FormatMetadata::getFormattedData().

Definition at line 147 of file XMP.php.

References as, list, and wfRunHooks().

XMPReader::parse	(	$	content,
		$	allOfIt = `true`,
		$	reset = `false`
	)

Main function to call to parse XMP.

Use getResults to get results.

Also catches any errors during processing, writes them to debug log, blanks result array and returns false.

Parameters:

string	$content	XMP data
	$allOfIt	Boolean: If this is all the data (true) or if its split up (false). Default true
	$reset	Boolean: does xml parser need to be reset. Default false

Exceptions:

MWException

Returns:: Boolean success.

Definition at line 245 of file XMP.php.

References $error, $ok, array(), resetXMLParser(), wfDebugLog(), wfRestoreWarnings(), and wfSuppressWarnings().

Referenced by parseExtended(), and XMPTest\testXMPParse().

XMPReader::parseExtended ( $ content )

Entry point for XMPExtended blocks in jpeg files.

Todo:: In serious need of testing

See also:: http://www.adobe.ge/devnet/xmp/pdfs/XMPSpecificationPart3.pdf XMP spec part 3 page 20

Parameters:

string $content XMPExtended block minus the namespace signature

Returns:: Boolean If it succeeded.

Definition at line 316 of file XMP.php.

References parse(), resetXMLParser(), and wfDebugLog().

XMPReader::resetXMLParser ( ) [private]

Main use is if a single item has multiple xmp documents describing it.

For example in jpeg's with extendedXMP

Definition at line 114 of file XMP.php.

References array().

Referenced by __construct(), parse(), and parseExtended().

XMPReader::saveValue	(	$	ns,
		$	tag,
		$	val
	)		`[private]`

Given an extracted value, save it to results array.

note also uses $this->ancestorStruct and $this->processingArray to determine what name to save the value under. (in addition to $tag).

Parameters:

string	$ns	namespace of tag this is for
string	$tag	tag name
string	$val	value to save

Definition at line 1165 of file XMP.php.

References array(), and wfDebugLog().

Referenced by doAttribs(), endElementModeQDesc(), endElementModeSimple(), and startElementModeSimple().

XMPReader::startElement	(	$	parser,
		$	elm,
		$	attribs
	)

Hits an opening element.

Generally just calls a helper based on what MODE we're in. Also does some initial set up for the wrapper element

Parameters:

	$parser	XMLParser
string	$elm	namespace "<space>" element
array	$attribs	attribute name => value

Exceptions:

MWException

Definition at line 1025 of file XMP.php.

References $attribs, list, startElementModeBag(), startElementModeIgnore(), startElementModeInitial(), startElementModeLang(), startElementModeLi(), startElementModeLiLang(), startElementModeQDesc(), startElementModeSeq(), startElementModeSimple(), startElementModeStruct(), and wfDebugLog().

XMPReader::startElementModeBag ( $ elm ) [private]

Start element in MODE_BAG (unordered array) this should always be <rdf:Bag>

Parameters:

string $elm namespace . ' ' . tag

Exceptions:

MWException if we have an element that's not <rdf:Bag>

Definition at line 703 of file XMP.php.

Referenced by startElement().

XMPReader::startElementModeIgnore ( $ elm ) [private]

Hit an opening element while in MODE_IGNORE.

XMP is extensible, so ignore any tag we don't understand.

Mostly ignores, unless we encounter the element that we are ignoring. in which case we add it to the item stack, so we can ignore things that are nested, correctly.

Parameters:

string $elm namespace . ' ' . tag name

Definition at line 689 of file XMP.php.

Referenced by startElement().

XMPReader::startElementModeInitial	(	$	ns,
		$	tag,
		$	attribs
	)		`[private]`

Starting an element when in MODE_INITIAL This usually happens when we hit an element inside the outer rdf:Description.

This is generally where most properties start.

Parameters:

string	$ns	Namespace
string	$tag	tag name (without namespace prefix)
array	$attribs	array of attributes

Exceptions:

MWException

Definition at line 834 of file XMP.php.

References $attribs, $mode, doAttribs(), and wfDebugLog().

Referenced by startElement().

XMPReader::startElementModeLang ( $ elm ) [private]

Start element in MODE_LANG (language alternative) this should always be <rdf:Alt>

This tag tends to be used for metadata like describe this picture, which can be translated into multiple languages.

XMP supports non-linguistic alternative selections, which are really only used for thumbnails, which we don't care about.

Parameters:

string $elm namespace . ' ' . tag

Exceptions:

MWException if we have an element that's not <rdf:Alt>

Definition at line 747 of file XMP.php.

Referenced by startElement().

XMPReader::startElementModeLi	(	$	elm,
		$	attribs
	)		`[private]`

opening element in MODE_LI process elements of arrays.

Example: <exif:ISOSpeedRatings> <rdf:Seq> <rdf:li>64</rdf:li> </rdf:Seq> </exif:ISOSpeedRatings> This method is called when we hit the <rdf:li> element.

Parameters:

string	$elm	namespace . ' ' . tagname
array	$attribs	Attributes. (needed for BAGSTRUCTS)

Exceptions:

MWException if gets a tag other than <rdf:li>

Definition at line 942 of file XMP.php.

References $attribs, doAttribs(), and list.

Referenced by startElement().

XMPReader::startElementModeLiLang	(	$	elm,
		$	attribs
	)		`[private]`

Opening element in MODE_LI_LANG.

process elements of language alternatives

Example: <dc:title> <rdf:Alt> <rdf:li xml:lang="x-default">My house </rdf:li> </rdf:Alt> </dc:title>

This method is called when we hit the <rdf:li> element.

Parameters:

string	$elm	namespace . ' ' . tag
array	$attribs	array of elements (most importantly xml:lang)

Exceptions:

MWException if gets a tag other than <rdf:li> or if no xml:lang

Definition at line 994 of file XMP.php.

References $attribs.

Referenced by startElement().

XMPReader::startElementModeQDesc ( $ elm ) [private]

Start an element when in MODE_QDESC.

This generally happens when a simple element has an inner rdf:Description to hold qualifier elements.

For example in: <exif:DigitalZoomRatio><rdf:Description><rdf:value>0/10</rdf:value> <foo:someQualifier>Bar</foo:someQualifier> </rdf:Description> </exif:DigitalZoomRatio> Called when processing the <rdf:value> or <foo:someQualifier>.

Parameters:

string $elm namespace and tag name separated by a space.

Definition at line 812 of file XMP.php.

Referenced by startElement().

XMPReader::startElementModeSeq ( $ elm ) [private]

Start element in MODE_SEQ (ordered array) this should always be <rdf:Seq>

Parameters:

string $elm namespace . ' ' . tag

Exceptions:

MWException if we have an element that's not <rdf:Seq>

Definition at line 719 of file XMP.php.

References wfDebugLog().

Referenced by startElement().

XMPReader::startElementModeSimple	(	$	elm,
		$	attribs
	)		`[private]`

Handle an opening element when in MODE_SIMPLE.

This should not happen often. This is for if a simple element already opened has a child element. Could happen for a qualified element.

For example: <exif:DigitalZoomRatio><rdf:Description><rdf:value>0/10</rdf:value> <foo:someQualifier>Bar</foo:someQualifier> </rdf:Description> </exif:DigitalZoomRatio>

This method is called when processing the <rdf:Description> element

Parameters:

string	$elm	namespace and tag names separated by space.
array	$attribs	Attributes of the element.

Exceptions:

MWException

Definition at line 774 of file XMP.php.

References $attribs, list, saveValue(), and wfDebugLog().

Referenced by startElement().

XMPReader::startElementModeStruct	(	$	ns,
		$	tag,
		$	attribs
	)		`[private]`

Hit an opening element when in a Struct (MODE_STRUCT) This is generally for fields of a compound property.

Example of a struct (abbreviated; flash has more properties):

<exif:Flash> <rdf:Description> <exif:Fired>True</exif:Fired> <exif:Mode>1</exif:Mode></rdf:Description></exif:Flash>

or:

<exif:Flash rdf:parseType='Resource'> <exif:Fired>True</exif:Fired> <exif:Mode>1</exif:Mode></exif:Flash>

Parameters:

string	$ns	namespace
string	$tag	tag name (no ns)
array	$attribs	array of attribs w/ values.

Exceptions:

MWException

Definition at line 895 of file XMP.php.

References $attribs, and doAttribs().

Referenced by startElement().

Member Data Documentation

XMPReader::$ancestorStruct = false [private]

Definition at line 52 of file XMP.php.

XMPReader::$charContent = false [private]

Definition at line 53 of file XMP.php.

XMPReader::$charset = false [private]

Definition at line 60 of file XMP.php.

XMPReader::$curItem = array() [private]

Definition at line 51 of file XMP.php.

XMPReader::$extendedXMPOffset = 0 [private]

Definition at line 61 of file XMP.php.

XMPReader::$itemLang = false [private]

Definition at line 57 of file XMP.php.

XMPReader::$items [protected]

Definition at line 63 of file XMP.php.

XMPReader::$mode = array() [private]

Definition at line 54 of file XMP.php.

Referenced by startElementModeInitial().

XMPReader::$processingArray = false [private]

Definition at line 56 of file XMP.php.

XMPReader::$results = array() [private]

Definition at line 55 of file XMP.php.

XMPReader::$xmlParser [private]

Definition at line 59 of file XMP.php.

const XMPReader::MODE_ALT = 15

Definition at line 87 of file XMP.php.

const XMPReader::MODE_BAG = 13

Definition at line 85 of file XMP.php.

const XMPReader::MODE_BAGSTRUCT = 16

Definition at line 88 of file XMP.php.

const XMPReader::MODE_IGNORE = 1

Definition at line 75 of file XMP.php.

const XMPReader::MODE_INITIAL = 0

These are various mode constants.

they are used to figure out what to do with an element when its encountered.

For example, MODE_IGNORE is used when processing a property we're not interested in. So if a new element pops up when we're in that mode, we ignore it.

Definition at line 74 of file XMP.php.

const XMPReader::MODE_LANG = 14

Definition at line 86 of file XMP.php.

const XMPReader::MODE_LI = 2

Definition at line 76 of file XMP.php.

const XMPReader::MODE_LI_LANG = 3

Definition at line 77 of file XMP.php.

const XMPReader::MODE_QDESC = 4

Definition at line 78 of file XMP.php.

Referenced by doAttribs().

const XMPReader::MODE_SEQ = 12

Definition at line 84 of file XMP.php.