Docs For Class PelEntry

Description

Common ancestor class of all PelIfd entries.

As this class is abstract you cannot instantiate objects from it. It only serves as a common ancestor to define the methods common to all entries. The most important methods are getValue() and setValue(), both of which is abstract in this class. The descendants will give concrete implementations for them.

If you have some data coming from an image (some raw bytes), then the static method newFromData() is helpful --- it will look at the data and give you a proper decendent of PelEntry back.

If you instead want to have an entry for some data which take the form of an integer, a string, a byte, or some other PHP type, then don't use this class. You should instead create an object of the right subclass (PelEntryShort for short integers, PelEntryAscii for strings, and so on) directly.

author: Martin Geisler <mgeisler@users.sourceforge.net>
abstract:

Located in /src/PelEntry.php (line 194)

Direct descendents

Class	Description
PelEntryWindowsString	Class used to manipulate strings in the format Windows XP uses.
PelEntryNumber	Class for holding numbers.
PelEntryAscii	Class for holding a plain ASCII string.
PelEntryUndefined	Class for holding data of any kind.

Variable Summary

string $bytes

int $components

PelFormat $format

int $ifd_type

PelTag $tag

Method Summary

string getBytes (PelByteOrder $o)

int getComponents ()

PelFormat getFormat ()

int getIfdType ()

PelTag getTag ()

string getText ([boolean $brief = false])

mixed getValue ()

void setIfdType (int $type)

void setValue (mixed $value)

string __toString ()

Variables

string $bytes = '' (line 218)

The bytes representing this entry.

Subclasses must either override getBytes() or, if possible, maintain this property so that it always contains a true representation of the entry.

access: protected

int $components (line 239)

The number of components of this entry.

access: protected

PelFormat $format (line 232)

The PelFormat of this entry.

access: protected

int $ifd_type (line 207)

Type of IFD containing this tag.

This must be one of the constants defined in PelIfd: PelIfd::IFD0 for the main image IFD, PelIfd::IFD1 for the thumbnail image IFD, PelIfd::EXIF for the Exif sub-IFD, PelIfd::GPS for the GPS sub-IFD, or PelIfd::INTEROPERABILITY for the interoperability sub-IFD.

access: protected

PelTag $tag (line 225)

The PelTag of this entry.

access: protected

Methods

getBytes (line 309)

Turn this entry into bytes.

return: bytes representing this entry.

string getBytes (PelByteOrder $o)

PelByteOrder $o: the desired byte order, which must be either Convert::LITTLE_ENDIAN or Convert::BIG_ENDIAN.

Redefined in descendants as:

PelEntryNumber::getBytes() : Turn this entry into bytes.

getComponents (line 296)

Return the number of components of this entry.

return: the number of components of this entry.

int getComponents ()

getFormat (line 286)

Return the format of this entry.

return: the format of this entry.

PelFormat getFormat ()

getIfdType (line 261)

Return the type of IFD which holds this entry.

return: one of the constants defined in PelIfd: PelIfd::IFD0 for the main image IFD, PelIfd::IFD1 for the thumbnail image IFD, PelIfd::EXIF for the Exif sub-IFD, PelIfd::GPS for the GPS sub-IFD, or PelIfd::INTEROPERABILITY for the interoperability sub-IFD.

int getIfdType ()

getTag (line 247)

Return the tag of this entry.

return: the tag of this entry.

PelTag getTag ()

getText (line 326)

Get the value of this entry as text.

The value will be returned in a format suitable for presentation, e.g., rationals will be returned as 'x/y', ASCII strings will be returned as themselves etc.

return: the value as text.
abstract:

string getText ([boolean $brief = false])

boolean $brief: some values can be returned in a long or more brief form, and this parameter controls that.

Redefined in descendants as:

PelEntryWindowsString::getText() : Return the string of the entry.
PelEntryNumber::getText() : Get the numeric value of this entry as text.
PelEntryShort::getText() : Get the value of an entry as text.
PelEntryRational::getText() : Get the value of an entry as text.
PelEntrySRational::getText() : Get the value of an entry as text.
PelEntryAscii::getText() : Return the ASCII string of the entry.
PelEntryCopyright::getText() : Return a text string with the copyright information.
PelEntryUndefined::getText() : Get the value of this entry as text.
PelEntryUserComment::getText() : Returns the user comment.
PelEntryVersion::getText() : Return a text string with the version.

getValue (line 338)

Get the value of this entry.

The value returned will generally be the same as the one supplied to the constructor or with setValue(). For a formatted version of the value, one should use getText() instead.

return: the unformatted value.
abstract:

mixed getValue ()

Redefined in descendants as:

PelEntryWindowsString::getValue() : Return the string of the entry.
PelEntryNumber::getValue() : Return the numeric value held.
PelEntryAscii::getValue() : Return the ASCII string of the entry.
PelEntryTime::getValue() : Return the timestamp of the entry.
PelEntryCopyright::getValue() : Retrive the copyright information.
PelEntryUndefined::getValue() : Get the data of this undefined entry.
PelEntryUserComment::getValue() : Returns the user comment.
PelEntryVersion::getValue() : Return the version held by this entry.

setIfdType (line 276)

Update the IFD type.

void setIfdType (int $type)

int $type: must be one of the constants defined in PelIfd: PelIfd::IFD0 for the main image IFD, PelIfd::IFD1 for the thumbnail image IFD, PelIfd::EXIF for the Exif sub-IFD, PelIfd::GPS for the GPS sub-IFD, or PelIfd::INTEROPERABILITY for the interoperability sub-IFD.

setValue (line 350)

Set the value of this entry.

The value should be in the same format as for the constructor.

abstract:

void setValue (mixed $value)

mixed $value: the new value.

Redefined in descendants as:

PelEntryWindowsString::setValue() : Give the entry a new value.
PelEntryNumber::setValue() : Change the value.
PelEntryAscii::setValue() : Give the entry a new ASCII value.
PelEntryTime::setValue() : Update the timestamp held by this entry.
PelEntryCopyright::setValue() : Update the copyright information.
PelEntryUndefined::setValue() : Set the data of this undefined entry.
PelEntryUserComment::setValue() : Set the user comment.
PelEntryVersion::setValue() : Set the version held by this entry.

__toString (line 368)

Turn this entry into a string.

return: a string representation of this entry. This is mostly for debugging.

string __toString ()