diff --git a/dlls/windowscodecs/proxy.c b/dlls/windowscodecs/proxy.c
index 150983f9c41..082bc0cfd30 100644
--- a/dlls/windowscodecs/proxy.c
+++ b/dlls/windowscodecs/proxy.c
@@ -84,6 +84,54 @@ HRESULT WINAPI IWICBitmapCodecInfo_DoesSupportMultiframe_Proxy_W(IWICBitmapCodec
     return IWICBitmapCodecInfo_DoesSupportMultiframe(iface, pfSupportMultiframe);
 }
 
+HRESULT WINAPI IWICBitmapDecoder_GetDecoderInfo_Proxy_W(IWICBitmapDecoder *iface,
+    IWICBitmapDecoderInfo **ppIDecoderInfo)
+{
+    return IWICBitmapDecoder_GetDecoderInfo(iface, ppIDecoderInfo);
+}
+
+HRESULT WINAPI IWICBitmapDecoder_CopyPalette_Proxy_W(IWICBitmapDecoder *iface,
+    IWICPalette *pIPalette)
+{
+    return IWICBitmapDecoder_CopyPalette(iface, pIPalette);
+}
+
+HRESULT WINAPI IWICBitmapDecoder_GetMetadataQueryReader_Proxy_W(IWICBitmapDecoder *iface,
+    IWICMetadataQueryReader **ppIMetadataQueryReader)
+{
+    return IWICBitmapDecoder_GetMetadataQueryReader(iface, ppIMetadataQueryReader);
+}
+
+HRESULT WINAPI IWICBitmapDecoder_GetPreview_Proxy_W(IWICBitmapDecoder *iface,
+    IWICBitmapSource **ppIBitmapSource)
+{
+    return IWICBitmapDecoder_GetPreview(iface, ppIBitmapSource);
+}
+
+HRESULT WINAPI IWICBitmapDecoder_GetColorContexts_Proxy_W(IWICBitmapDecoder *iface,
+    UINT cCount, IWICColorContext **ppIColorContexts, UINT *pcActualCount)
+{
+    return IWICBitmapDecoder_GetColorContexts(iface, cCount, ppIColorContexts, pcActualCount);
+}
+
+HRESULT WINAPI IWICBitmapDecoder_GetThumbnail_Proxy_W(IWICBitmapDecoder *iface,
+    IWICBitmapSource **ppIThumbnail)
+{
+    return IWICBitmapDecoder_GetThumbnail(iface, ppIThumbnail);
+}
+
+HRESULT WINAPI IWICBitmapDecoder_GetFrameCount_Proxy_W(IWICBitmapDecoder *iface,
+    UINT *pCount)
+{
+    return IWICBitmapDecoder_GetFrameCount(iface, pCount);
+}
+
+HRESULT WINAPI IWICBitmapDecoder_GetFrame_Proxy_W(IWICBitmapDecoder *iface,
+    UINT index, IWICBitmapFrameDecode **ppIBitmapFrame)
+{
+    return IWICBitmapDecoder_GetFrame(iface, index, ppIBitmapFrame);
+}
+
 HRESULT WINAPI IWICBitmapFlipRotator_Initialize_Proxy_W(IWICBitmapFlipRotator *iface,
     IWICBitmapSource *pISource, WICBitmapTransformOptions options)
 {
diff --git a/dlls/windowscodecs/windowscodecs.spec b/dlls/windowscodecs/windowscodecs.spec
index aecd87f528f..4ae0c413e1a 100644
--- a/dlls/windowscodecs/windowscodecs.spec
+++ b/dlls/windowscodecs/windowscodecs.spec
@@ -14,14 +14,14 @@
 @ stdcall IWICBitmapCodecInfo_GetDeviceModels_Proxy(ptr long ptr ptr) IWICBitmapCodecInfo_GetDeviceModels_Proxy_W
 @ stdcall IWICBitmapCodecInfo_GetFileExtensions_Proxy(ptr long ptr ptr) IWICBitmapCodecInfo_GetFileExtensions_Proxy_W
 @ stdcall IWICBitmapCodecInfo_GetMimeTypes_Proxy(ptr long ptr ptr) IWICBitmapCodecInfo_GetMimeTypes_Proxy_W
-@ stub IWICBitmapDecoder_CopyPalette_Proxy
-@ stub IWICBitmapDecoder_GetColorContexts_Proxy
-@ stub IWICBitmapDecoder_GetDecoderInfo_Proxy
-@ stub IWICBitmapDecoder_GetFrameCount_Proxy
-@ stub IWICBitmapDecoder_GetFrame_Proxy
-@ stub IWICBitmapDecoder_GetMetadataQueryReader_Proxy
-@ stub IWICBitmapDecoder_GetPreview_Proxy
-@ stub IWICBitmapDecoder_GetThumbnail_Proxy
+@ stdcall IWICBitmapDecoder_CopyPalette_Proxy(ptr ptr) IWICBitmapDecoder_CopyPalette_Proxy_W
+@ stdcall IWICBitmapDecoder_GetColorContexts_Proxy(ptr long ptr ptr) IWICBitmapDecoder_GetColorContexts_Proxy_W
+@ stdcall IWICBitmapDecoder_GetDecoderInfo_Proxy(ptr ptr) IWICBitmapDecoder_GetDecoderInfo_Proxy_W
+@ stdcall IWICBitmapDecoder_GetFrameCount_Proxy(ptr ptr) IWICBitmapDecoder_GetFrameCount_Proxy_W
+@ stdcall IWICBitmapDecoder_GetFrame_Proxy(ptr long ptr) IWICBitmapDecoder_GetFrame_Proxy_W
+@ stdcall IWICBitmapDecoder_GetMetadataQueryReader_Proxy(ptr ptr) IWICBitmapDecoder_GetMetadataQueryReader_Proxy_W
+@ stdcall IWICBitmapDecoder_GetPreview_Proxy(ptr ptr) IWICBitmapDecoder_GetPreview_Proxy_W
+@ stdcall IWICBitmapDecoder_GetThumbnail_Proxy(ptr ptr) IWICBitmapDecoder_GetThumbnail_Proxy_W
 @ stub IWICBitmapEncoder_Commit_Proxy
 @ stub IWICBitmapEncoder_CreateNewFrame_Proxy
 @ stub IWICBitmapEncoder_GetEncoderInfo_Proxy