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Updated to WebP v0.3.6 build 2025-07-02 beta -> you can convert now GIF animated files to WebP animated files (see Example10.au3 on my 1Drv).

Hello everyone, I'm pleased to share a UDF I developed to work with IWICImagingFactory from the Windows Imaging Component (WIC), focused exclusively on reading and writing image metadata. 🔍 Why this UDF? IWICImagingFactory is a powerful API but can also be particularly confusing when working with metadata. Its layers of abstraction, data formats, and interface complexity can easily distract you from your goals without a clear structure. 🧩 Key Features: 🔄 Read and write metadata using WIC interfaces (IWICMetadataQueryReader, IWICMetadataQueryWriter) 💾 Supports common formats (JPEG, PNG, TIFF, etc.) 🧠 Built using an object-oriented model via AutoItObject to encapsulate complexity and avoid side effects ⚠️ Full support for PROPVARIANT and VARIANT types, essential for COM interaction 🔗 Handles the WIC metadata query language (e.g., /app1/ifd/exif:{ushort=36867} for Date Taken) 📜 Works with WIC-compliant hierarchical metadata queries 🧠 Prerequisites / Recommended Knowledge Solid understanding of COM programming in AutoIt Familiarity with PROPVARIANT/VARIANT (types, conversion, init/cleanup) Knowledge of WIC metadata schema and hierarchy Comfortable with object-oriented programming in AutoIt (using AutoItObject) 🧪 Why use an object-oriented approach? IWICImagingFactory is as flexible as it is tricky. Exploring it directly can lead to unexpected behaviors or technical detours. The object-oriented approach helps contain this complexity, structure features properly, and avoid common pitfalls when dealing with raw COM interfaces. 📁 What’s Included in the UDF A main object WICImageMeta (or similar) that encapsulates the image, reader/writer, and associated interfaces Straightforward methods like .ReadMeta($sPath), .WriteMeta($sPath, $vValue, $sType), .Save($sDest), etc. Automatic resource management (Release, Cleanup) Examples for reading/writing EXIF, XMP, and other metadata 📷 Quick Usage Example #include <MsgBoxConstants.au3> #include <WinAPI.au3> #include <Array.au3> #include "IWICImagingMetadata.au3" ; This is your custom UDF for WIC metadata ; Path to a test image (replace with your own file path) Local $sFilename = @DesktopDir & "\screenshot.png" ; === 1. Create the WIC Imaging Factory === ; This is the entry point for all WIC operations Local $oFactory = _WIC_ImagingFactory() If Not IsObj($oFactory) Then MsgBox(0, "Error", "Failed to create WIC Imaging Factory") Exit EndIf ; === 2. Create a decoder from the image file === ; This will analyze the image format and prepare for frame extraction Local $oDecoder = $oFactory.createDecoderFromFileName($sFilename) If Not IsObj($oDecoder) Then MsgBox(0, "Error", "Failed to create image decoder: @error=" & @error) $oFactory = 0 Exit EndIf ; === 3. Get the first frame of the image === ; Most still images have a single frame; this retrieves it from the decoder Local $oFrame = $oFactory.createBitmapFrameDecode($oDecoder) If Not IsObj($oFrame) Then MsgBox($MB_ICONERROR, "Error", "Failed to retrieve image frame: @error=" & @error) $oDecoder = 0 $oFactory = 0 Exit EndIf ; === 4. Get a metadata query reader from the frame === ; This reader allows you to query metadata values using WIC metadata paths Local $oQueryReader = $oFactory.getMetadataQueryReader($oFrame) If Not IsObj($oQueryReader) Then MsgBox(0, "Error", "Failed to get metadata query reader: @error=" & @error) $oFrame = 0 $oDecoder = 0 $oFactory = 0 Exit EndIf ; === 5. Enumerate available metadata names === ; This step is crucial to explore what metadata is actually present. ; It returns an array of metadata query paths that can be used. Local $aNames = $oFactory.enumerateMetaDataNames($oQueryReader) If @error Then ConsoleWrite("Error: Failed to enumerate metadata names: @error=" & @error & @CRLF) Else ConsoleWrite("Available metadata names: " & _ArrayToString($aNames, "|") & @CRLF) EndIf ; === 6. Read a specific metadata value === ; In this case, we're trying to read a textual field: "Creation Time" in a PNG tEXt chunk Local $sQuery = "/tEXt/{str=Creation Time}" Local $vData = $oFactory.queryMetadataByName($oQueryReader, $sQuery) If Not @error Then ConsoleWrite("Metadata read: " & $sQuery & " = " & $vData & @CRLF) Else ConsoleWrite("Error: Failed to read " & $sQuery & " : @error=" & @error & @CRLF) EndIf ; === NOTE === ; If your query selects a metadata **block**, then `vData` may be another IWICMetadataQueryReader object. ; In that case, you must call `queryMetadataByName` again, passing this sub-reader to reach nested values. 💬 Conclusion If you've worked with image metadata using WIC before, you know it's a technical challenge. This UDF aims to simplify the process while preserving full control for those who need fine-grained access. Feel free to try it out, give feedback, or suggest improvements. Enjoy digging into the hidden data of your images! 📸 IWICImagingMetadata.au3

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