See the question and my original answer on StackOverflow

If you have an IWICBitmapDecoder reference, you can call the IWICBitmapDecoder::GetDecoderInfo method. It will get you an IWICBitmapDecoderInfo reference ("Exposes methods that provide information about a decoder.").

From that reference (which derives from the IWICComponentInfo interface), you can call the IWICComponentInfo::GetFriendlyName method which will get you "GIF Decoder" in the GIF decoder (GUID_ContainerFormatGif) case.

This WicNetExplorer open source (.NET C# P/Invoke interop) tool I wrote can display every WIC Component information:

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