--- product: Chilkat product_version: 11.7.0 language: pascal language_label: Lazarus Pascal class: Xmp license: bundle deprecated: false reference_html: https://www.chilkatsoft.com/refdoc/pascal_XmpRef.html --- # Chilkat Xmp — Lazarus Pascal — v11.7.0 > Chilkat 11.7.0 · language=pascal · class=Xmp > Other versions: replace `11.7.0` in this URL. Other languages: `https://www.chilkatsoft.com/ai-docs/v/11.7.0//classes/Xmp.md`. > Language-wide rules (install, unlock, error model, strings/bytes): `https://www.chilkatsoft.com/ai-docs/v/11.7.0/pascal/guide.md`. ## Purpose **Read, modify, add, remove, and save XMP metadata in JPG and TIFF files.** `Chilkat.Xmp` is a legacy class for working with embedded XMP metadata in `JPG` and `TIFF` image files. It can load image files or image data from memory, locate embedded XMP documents, return XMP metadata as `Chilkat.Xml`, create new XMP documents, add or update simple string and integer properties, manage arrays and structured properties, add namespace mappings, remove selected XMP properties or entire embedded XMP documents, and save the updated image back to a file or byte buffer. **Legacy class:** `Chilkat.Xmp` is maintained for existing JPG/TIFF XMP workflows, but it is not planned to be extended to support additional file types. **Load JPG or TIFF metadata** Load a `JPG` or `TIFF` file from disk or memory and inspect how many embedded XMP documents were found. **Access XMP as XML** Retrieve embedded XMP documents as `Chilkat.Xml` objects for inspection, editing, or direct XML-level processing. **Add simple properties** Add or update namespace-qualified string and integer properties such as `dc:subject`, `photoshop:Credit`, or `tiff:XResolution`. **Arrays and structures** Work with XMP arrays such as `bag`, `seq`, and `alt`, and manage structured property values. **Namespaces** Use built-in namespace mappings or add custom namespace-to-URI mappings for application-specific XMP properties. **Remove and save** Remove properties, arrays, structures, or embedded XMP documents, then persist changes to a file or return the updated image as a byte buffer. **Common pattern:** Load a JPG or TIFF with `LoadAppFile` or `LoadFromBuffer`, retrieve an embedded XMP document with `GetEmbedded` or create one with `NewXmp`, modify it using the add/remove property methods, then call `SaveAppFile` or `SaveToBuffer` to persist the updated image metadata. **Persistence note:** Changes made to the XMP XML object are not written back to the image file until `SaveAppFile` is called. For memory workflows, use `SaveToBuffer` to obtain the updated JPG or TIFF bytes. ## Object creation, unlocking and error handling **Create / Free** ```pascal uses Chilkat.Xmp; var obj: TXmp; begin obj := TXmp.Create; try if not obj.IsValid then raise Exception.Create('Failed to create a TXmp instance.'); // ... use obj ... finally obj.Free; end; end; ``` `constructor Create;` Allocates the underlying CkXmp object and returns a new TXmp instance. Simply adding **Chilkat.Xmp** to the unit's `uses` clause is enough to locate and bind to the Chilkat shared library (DLL / .so / .dylib) at runtime — no separate load step is required. Check `obj.IsValid` after calling `Create`; it is `False` if the underlying library could not be found/loaded or the object could not be allocated (for example, when unlicensed). `destructor Destroy; override;` Every TXmp created by calling `Create` should eventually be released by calling `.Free` (inherited from `TObject`). The destructor automatically disposes the underlying CkXmp handle. A native (unmanaged) memory leak occurs if the object is never freed. Call `Global.UnlockBundle` once at the start of the program, before using this or any other Chilkat class. Any string unlocks a fully functional 30-day trial; a purchased unlock code is used in production. See `guide.md` for the exact code in Lazarus Pascal. ## Members common to every Chilkat class Documented once per language in `common-members.md`; listed here so this page is self-contained. | Property | Signature | Access | Meaning | |---|---|---|---| | `DebugLogFilePath` | `property DebugLogFilePath: string read GetDebugLogFilePath write SetDebugLogFilePath;` | read/write | If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. | | `LastErrorHtml` | `property LastErrorHtml: string read GetLastErrorHtml;` | read-only | Provides HTML-formatted information about the last called method or property. | | `LastErrorText` | `property LastErrorText: string read GetLastErrorText;` | read-only | Provides plain text information about the last called method or property. | | `LastErrorXml` | `property LastErrorXml: string read GetLastErrorXml;` | read-only | Provides XML-formatted information about the last called method or property. | | `LastMethodSuccess` | `property LastMethodSuccess: Boolean read GetLastMethodSuccess write SetLastMethodSuccess;` | read/write | Indicates the success or failure of the most recent method call: `True` means success, `False` means failure. | | `VerboseLogging` | `property VerboseLogging: Boolean read GetVerboseLogging write SetVerboseLogging;` | read/write | If set to `True`, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. | | `Version` | `property Version: string read GetVersion;` | read-only | Version of the component/library, such as "10.1.0" | ## Member index | Member | Kind | Signature | |---|---|---| | `NumEmbedded` | property, read-only | `property NumEmbedded: Integer read GetNumEmbedded;` | | `StructInnerDescrip` | property, read/write | `property StructInnerDescrip: Boolean read GetStructInnerDescrip write SetStructInnerDescrip;` | | `UncommonOptions` | property, read/write | `property UncommonOptions: string read GetUncommonOptions write SetUncommonOptions;` | | `AddArray` | method | `// xml is a TXml object. // values is a TStringArray object. function AddArray(xml: TChilkatBase;     const arrType: string;     const propName: string;     values: TChilkatBase): Boolean;` | | `AddNsMapping` | method | `procedure AddNsMapping(const ns: string;     const uri: string);` | | `AddSimpleInt` | method | `// iXml is a TXml object. function AddSimpleInt(iXml: TChilkatBase;     const propName: string;     propVal: Integer): Boolean;` | | `AddSimpleStr` | method | `// iXml is a TXml object. function AddSimpleStr(iXml: TChilkatBase;     const propName: string;     const propVal: string): Boolean;` | | `AddStructProp` | method | `// iChilkatXml is a TXml object. function AddStructProp(iChilkatXml: TChilkatBase;     const structName: string;     const propName: string;     const propValue: string): Boolean;` | | `Append` | method | `// iXml is a TXml object. function Append(iXml: TChilkatBase): Boolean;` | | `GetArray` | method | `// iXml is a TXml object. // Return value is a TStringArray object. function GetArray(iXml: TChilkatBase;     const propName: string): TChilkatBase;` | | `GetEmbedded` | method | `// Return value is a TXml object. function GetEmbedded(index: Integer): TChilkatBase;` | | `GetProperty` | method | `// iXml is a TXml object. // Return value is a TXml object. function GetProperty(iXml: TChilkatBase;     const propName: string): TChilkatBase;` | | `GetSimpleInt` | method | `// iXml is a TXml object. function GetSimpleInt(iXml: TChilkatBase;     const propName: string): Integer;` | | `GetSimpleStr` | method | `// iXml is a TXml object. function GetSimpleStr(iXml: TChilkatBase;     const propName: string): string;` | | `GetStructPropNames` | method | `// iXml is a TXml object. // Return value is a TStringArray object. function GetStructPropNames(iXml: TChilkatBase;     const structName: string): TChilkatBase;` | | `GetStructValue` | method | `// iXml is a TXml object. function GetStructValue(iXml: TChilkatBase;     const structName: string;     const propName: string): string;` | | `LoadAppFile` | method | `function LoadAppFile(const filename: string): Boolean;` | | `NewXmp` | method | `// Return value is a TXml object. function NewXmp: TChilkatBase;` | | `RemoveAllEmbedded` | method | `function RemoveAllEmbedded: Boolean;` | | `RemoveArray` | method | `// iXml is a TXml object. function RemoveArray(iXml: TChilkatBase;     const propName: string): Boolean;` | | `RemoveEmbedded` | method | `function RemoveEmbedded(index: Integer): Boolean;` | | `RemoveNsMapping` | method | `procedure RemoveNsMapping(const ns: string);` | | `RemoveSimple` | method | `// iXml is a TXml object. function RemoveSimple(iXml: TChilkatBase;     const propName: string): Boolean;` | | `RemoveStruct` | method | `// iXml is a TXml object. function RemoveStruct(iXml: TChilkatBase;     const structName: string): Boolean;` | | `RemoveStructProp` | method | `// iXml is a TXml object. function RemoveStructProp(iXml: TChilkatBase;     const structName: string;     const propName: string): Boolean;` | | `SaveAppFile` | method | `function SaveAppFile(const filename: string): Boolean;` | ## Properties ### Xmp.NumEmbedded `Chilkat 11.7.0 · pascal · Xmp · NumEmbedded · property · read-only` ```pascal property NumEmbedded: Integer read GetNumEmbedded; ``` The number of XMP metadata documents found within the JPG or TIFF file loaded by LoadAppFile. ### Xmp.StructInnerDescrip `Chilkat 11.7.0 · pascal · Xmp · StructInnerDescrip · property · read/write` ```pascal property StructInnerDescrip: Boolean read GetStructInnerDescrip write SetStructInnerDescrip; ``` Determines whether structures are stored with rdf:parseType=`Resource`, or within an `rdf:Description` sub-node. ### Xmp.UncommonOptions `Chilkat 11.7.0 · pascal · Xmp · UncommonOptions · property · read/write · since 9.5.0.80` ```pascal property UncommonOptions: string read GetUncommonOptions write SetUncommonOptions; ``` A property to be used for future uncommon needs. The default value is the empty string. ## Methods ### Xmp.AddArray `Chilkat 11.7.0 · pascal · Xmp · AddArray · method` ```pascal // xml is a TXml object. // values is a TStringArray object. function AddArray(xml: TChilkatBase;     const arrType: string;     const propName: string;     values: TChilkatBase): Boolean; ``` Adds or replaces an XMP property array. The XMP metadata to be updated is contained in the XML object passed in the 1st argument. The 2nd argument specifies the array type, which can be `bag`, `seq`, or `alt`. The property name should be prefixed with the namespace, such as `dc:subject`. Returns True for success, False for failure. ### Xmp.AddNsMapping `Chilkat 11.7.0 · pascal · Xmp · AddNsMapping · method` ```pascal procedure AddNsMapping(const ns: string;     const uri: string); ``` Adds a namespace to URI mapping. When a property is added via AddSimpleString or any of the other methods, the property name is namespace qualified. When adding the first property in a namespace, the rdf:Description is automatically added and the URI is obtained from the namespace-to-URI mappings. The standard (and commonly used) namespace mappings are defined by default. This is only used if the namespace is custom or not already handled. ### Xmp.AddSimpleInt `Chilkat 11.7.0 · pascal · Xmp · AddSimpleInt · method` ```pascal // iXml is a TXml object. function AddSimpleInt(iXml: TChilkatBase;     const propName: string;     propVal: Integer): Boolean; ``` Adds or updates an XMP integer property. The XMP metadata to be updated is contained in the XML object passed in the 1st argument. The property name should be prefixed with the namespace, such as `tiff:XResolution`. Returns True for success, False for failure. ### Xmp.AddSimpleStr `Chilkat 11.7.0 · pascal · Xmp · AddSimpleStr · method` ```pascal // iXml is a TXml object. function AddSimpleStr(iXml: TChilkatBase;     const propName: string;     const propVal: string): Boolean; ``` Adds or updates a simple XMP string property. The XMP metadata to be updated is contained in the XML object passed in the 1st argument. The property name should be prefixed with the namespace, such as `photoshop:Credit`. Returns True for success, False for failure. ### Xmp.AddStructProp `Chilkat 11.7.0 · pascal · Xmp · AddStructProp · method` ```pascal // iChilkatXml is a TXml object. function AddStructProp(iChilkatXml: TChilkatBase;     const structName: string;     const propName: string;     const propValue: string): Boolean; ``` Adds or updates an XMP structured property value. The XMP metadata to be updated is contained in the XML object passed in the 1st argument. The structure name should be prefixed with the namespace, such as `Iptc4xmpCore:CreatorContactInfo`. The property name within the structure should also be prefixed with the namespace, such as `Iptc4xmpCore:CiAdrCity`. Returns True for success, False for failure. ### Xmp.Append `Chilkat 11.7.0 · pascal · Xmp · Append · method` ```pascal // iXml is a TXml object. function Append(iXml: TChilkatBase): Boolean; ``` Appends a new XMP metadata file to the XMP object. Any XMPs appended via this method will be present in the file when SaveAppFile is called. Files containing XMP metadata typically only include a single XMP document, so this method is usually only called when adding XMP metadata to a file for the first time. Returns True for success, False for failure. ### Xmp.GetArray `Chilkat 11.7.0 · pascal · Xmp · GetArray · method` ```pascal // iXml is a TXml object. // Return value is a TStringArray object. function GetArray(iXml: TChilkatBase;     const propName: string): TChilkatBase; ``` Finds and returns an XMP array property. The property name should be prefixed with the namespace, such as `dc:subject`. Returns `nil` on failure ### Xmp.GetEmbedded `Chilkat 11.7.0 · pascal · Xmp · GetEmbedded · method` ```pascal // Return value is a TXml object. function GetEmbedded(index: Integer): TChilkatBase; ``` Returns the Nth embedded XMP document as a Chilkat XML object. Returns `nil` on failure ### Xmp.GetProperty `Chilkat 11.7.0 · pascal · Xmp · GetProperty · method` ```pascal // iXml is a TXml object. // Return value is a TXml object. function GetProperty(iXml: TChilkatBase;     const propName: string): TChilkatBase; ``` To be documented soon... Returns `nil` on failure ### Xmp.GetSimpleInt `Chilkat 11.7.0 · pascal · Xmp · GetSimpleInt · method` ```pascal // iXml is a TXml object. function GetSimpleInt(iXml: TChilkatBase;     const propName: string): Integer; ``` Finds and returns an XMP integer property. The property name should be prefixed with the namespace, such as `tiff:ResolutionUnit`. ### Xmp.GetSimpleStr `Chilkat 11.7.0 · pascal · Xmp · GetSimpleStr · method` ```pascal // iXml is a TXml object. function GetSimpleStr(iXml: TChilkatBase;     const propName: string): string; ``` Finds and returns an XMP simple string property. The property name should be prefixed with the namespace, such as `photoshop:Source`. Returns True for success, False for failure. ### Xmp.GetStructPropNames `Chilkat 11.7.0 · pascal · Xmp · GetStructPropNames · method` ```pascal // iXml is a TXml object. // Return value is a TStringArray object. function GetStructPropNames(iXml: TChilkatBase;     const structName: string): TChilkatBase; ``` Returns the property names used by an exsting structure within an XMP document. The contents of the structure can be retrieved by calling GetStructValue for each property name returned by GetStructPropNames. Returns `nil` on failure ### Xmp.GetStructValue `Chilkat 11.7.0 · pascal · Xmp · GetStructValue · method` ```pascal // iXml is a TXml object. function GetStructValue(iXml: TChilkatBase;     const structName: string;     const propName: string): string; ``` Returns the value of a single item within an XMP structure property. Property names should always be prefixed with the namespace. Returns True for success, False for failure. ### Xmp.LoadAppFile `Chilkat 11.7.0 · pascal · Xmp · LoadAppFile · method` ```pascal function LoadAppFile(const filename: string): Boolean; ``` Loads a TIFF or JPG file into the XMP object. Returns True for success, False for failure. ### Xmp.NewXmp `Chilkat 11.7.0 · pascal · Xmp · NewXmp · method` ```pascal // Return value is a TXml object. function NewXmp: TChilkatBase; ``` Creates and returns a new/empty XMP metadata document as a Chilkat XML object. Returns `nil` on failure ### Xmp.RemoveAllEmbedded `Chilkat 11.7.0 · pascal · Xmp · RemoveAllEmbedded · method` ```pascal function RemoveAllEmbedded: Boolean; ``` Removes all XMP metadata documents from an XMP object. After calling this method, call SaveAppFile to rewrite the JPG or TIFF file with the XMP metadata removed. Returns True for success, False for failure. ### Xmp.RemoveArray `Chilkat 11.7.0 · pascal · Xmp · RemoveArray · method` ```pascal // iXml is a TXml object. function RemoveArray(iXml: TChilkatBase;     const propName: string): Boolean; ``` Removes an XMP array property from the XMP document. Returns True for success, False for failure. ### Xmp.RemoveEmbedded `Chilkat 11.7.0 · pascal · Xmp · RemoveEmbedded · method` ```pascal function RemoveEmbedded(index: Integer): Boolean; ``` Removes a single XMP metadata document from the JPG or TIFF file. Call SaveAppFile to persist the changes to disk. Returns True for success, False for failure. ### Xmp.RemoveNsMapping `Chilkat 11.7.0 · pascal · Xmp · RemoveNsMapping · method` ```pascal procedure RemoveNsMapping(const ns: string); ``` Removes a namespace-to-URI mapping. ### Xmp.RemoveSimple `Chilkat 11.7.0 · pascal · Xmp · RemoveSimple · method` ```pascal // iXml is a TXml object. function RemoveSimple(iXml: TChilkatBase;     const propName: string): Boolean; ``` Removes a simple XMP property from the XMP document. Returns True for success, False for failure. ### Xmp.RemoveStruct `Chilkat 11.7.0 · pascal · Xmp · RemoveStruct · method` ```pascal // iXml is a TXml object. function RemoveStruct(iXml: TChilkatBase;     const structName: string): Boolean; ``` Removes an XMP structure property from the XMP document. Returns True for success, False for failure. ### Xmp.RemoveStructProp `Chilkat 11.7.0 · pascal · Xmp · RemoveStructProp · method` ```pascal // iXml is a TXml object. function RemoveStructProp(iXml: TChilkatBase;     const structName: string;     const propName: string): Boolean; ``` Removes a single member from an XMP structured property. Returns True for success, False for failure. ### Xmp.SaveAppFile `Chilkat 11.7.0 · pascal · Xmp · SaveAppFile · method` ```pascal function SaveAppFile(const filename: string): Boolean; ``` Persists all changes made to the XMP document(s) by saving the XMP object to a file. Changes made by adding, updating, or removing properties are not persisted to the filesystem until this is called. Returns True for success, False for failure. ## Related classes [`StringArray`](https://www.chilkatsoft.com/ai-docs/v/11.7.0/pascal/classes/StringArray.md), [`Xml`](https://www.chilkatsoft.com/ai-docs/v/11.7.0/pascal/classes/Xml.md)