Tools: [skip ci] in thumbnail provider replace CxImage library with Win32 API

src/Tools/thumbs/FCStdExtractor.cpp

@@ -32,8 +32,132 @@
 #include <iostream>
 #include <zipios++/zipinputstream.h>
 #include <zipios++/zipfile.h>
-#include <CxImage/xmemfile.h>
-#include <CxImage/ximapng.h>
+#include <wincodec.h>
+#include <wincodecsdk.h>
+#pragma comment(lib, "WindowsCodecs.lib")
+
+ // The functions
+ // * CreateStreamOnResource
+ // * LoadBitmapFromStream
+ // * CreateHBITMAP
+ // are taken from https://faithlife.codes/blog/2008/09/displaying_a_splash_screen_with_c_part_i/
+ // The code is released under an MIT-style license
+
+ // Creates a stream object initialized with the data from an executable resource.
+IStream* CreateStreamOnResource(void* buffer, size_t length)
+{
+    // initialize return value
+    IStream* ipStream = NULL;
+
+    // allocate memory to hold the resource data
+    HGLOBAL hgblResourceData = GlobalAlloc(GMEM_MOVEABLE, length);
+    if (hgblResourceData == NULL)
+        goto Return;
+
+    // get a pointer to the allocated memory
+    LPVOID pvResourceData = GlobalLock(hgblResourceData);
+    if (pvResourceData == NULL)
+        goto FreeData;
+
+    // copy the data from the resource to the new memory block
+    CopyMemory(pvResourceData, buffer, length);
+    GlobalUnlock(hgblResourceData);
+
+    // create a stream on the HGLOBAL containing the data
+
+    if (SUCCEEDED(CreateStreamOnHGlobal(hgblResourceData, TRUE, &ipStream)))
+        goto Return;
+
+FreeData:
+    // couldn't create stream; free the memory
+
+    GlobalFree(hgblResourceData);
+
+Return:
+    // no need to unlock or free the resource
+    return ipStream;
+}
+
+IWICBitmapSource* LoadBitmapFromStream(IStream* ipImageStream)
+{
+    // initialize return value
+    IWICBitmapSource* ipBitmap = NULL;
+
+    // load WIC's PNG decoder
+    IWICBitmapDecoder* ipDecoder = NULL;
+    if (FAILED(CoCreateInstance(CLSID_WICPngDecoder, NULL, CLSCTX_INPROC_SERVER, __uuidof(ipDecoder), reinterpret_cast<void**>(&ipDecoder))))
+        goto Return;
+
+    // load the PNG
+    if (FAILED(ipDecoder->Initialize(ipImageStream, WICDecodeMetadataCacheOnLoad)))
+        goto ReleaseDecoder;
+
+    // check for the presence of the first frame in the bitmap
+    UINT nFrameCount = 0;
+    if (FAILED(ipDecoder->GetFrameCount(&nFrameCount)) || nFrameCount != 1)
+        goto ReleaseDecoder;
+
+    // load the first frame (i.e., the image)
+    IWICBitmapFrameDecode* ipFrame = NULL;
+    if (FAILED(ipDecoder->GetFrame(0, &ipFrame)))
+        goto ReleaseDecoder;
+
+    // convert the image to 32bpp BGRA format with pre-multiplied alpha
+    //   (it may not be stored in that format natively in the PNG resource,
+    //   but we need this format to create the DIB to use on-screen)
+    WICConvertBitmapSource(GUID_WICPixelFormat32bppPBGRA, ipFrame, &ipBitmap);
+    ipFrame->Release();
+
+ReleaseDecoder:
+    ipDecoder->Release();
+Return:
+    return ipBitmap;
+}
+
+HBITMAP CreateHBITMAP(IWICBitmapSource* ipBitmap)
+{
+    // initialize return value
+    HBITMAP hbmp = NULL;
+
+    // get image attributes and check for valid image
+    UINT width = 0;
+    UINT height = 0;
+    if (FAILED(ipBitmap->GetSize(&width, &height)) || width == 0 || height == 0)
+        goto Return;
+
+    // prepare structure giving bitmap information (negative height indicates a top-down DIB)
+    BITMAPINFO bminfo;
+    ZeroMemory(&bminfo, sizeof(bminfo));
+    bminfo.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
+    bminfo.bmiHeader.biWidth = width;
+    bminfo.bmiHeader.biHeight = -((LONG)height);
+    bminfo.bmiHeader.biPlanes = 1;
+    bminfo.bmiHeader.biBitCount = 32;
+    bminfo.bmiHeader.biCompression = BI_RGB;
+
+    // create a DIB section that can hold the image
+    void* pvImageBits = NULL;
+    HDC hdcScreen = GetDC(NULL);
+    hbmp = CreateDIBSection(hdcScreen, &bminfo, DIB_RGB_COLORS, &pvImageBits, NULL, 0);
+    ReleaseDC(NULL, hdcScreen);
+    if (hbmp == NULL)
+        goto Return;
+
+    // extract the image into the HBITMAP
+
+    const UINT cbStride = width * 4;
+    const UINT cbImage = cbStride * height;
+    if (FAILED(ipBitmap->CopyPixels(NULL, cbStride, cbImage, static_cast<BYTE*>(pvImageBits))))
+    {
+        // couldn't extract image; delete HBITMAP
+
+        DeleteObject(hbmp);
+        hbmp = NULL;
+    }
+
+Return:
+    return hbmp;
+}
 
 CComModule _Module;
 
@@ -146,13 +270,17 @@ HRESULT CFCStdExtractor::Extract(HBITMAP* phBmpThumbnail)
                 content.push_back(c);
             }
 
-            // pass the memory buffer to CxImage library to create
-            // the bitmap handle
-            CxMemFile mem(&(content[0]),content.size());
-            CxImagePNG png;
-            png.Decode(&mem);
-            m_hPreview = png.MakeBitmap();
-            *phBmpThumbnail = m_hPreview;
+            // pass the memory buffer to CxImage library to create the bitmap handle
+            IStream* stream = CreateStreamOnResource(&(content[0]), content.size());
+            if (stream) {
+                IWICBitmapSource* bmpSrc = LoadBitmapFromStream(stream);
+                stream->Release();
+                if (bmpSrc) {
+                    m_hPreview = CreateHBITMAP(bmpSrc);
+                    *phBmpThumbnail = m_hPreview;
+                    bmpSrc->Release();
+                }
+            }
         }
     }
     catch(...) {