windowscodecs: Set palette in WriteSource when necessary.

dlls/windowscodecs/bmpencode.c

@@ -316,7 +316,8 @@ static HRESULT WINAPI BmpFrameEncode_WriteSource(IWICBitmapFrameEncode *iface,
     if (SUCCEEDED(hr))
     {
         hr = write_source(iface, pIBitmapSource, prc,
-            This->format->guid, This->format->bpp, This->width, This->height);
+            This->format->guid, This->format->bpp, !This->colors && This->format->colors,
+            This->width, This->height);
     }
 
     return hr;

dlls/windowscodecs/jpegformat.c

@@ -1181,7 +1181,8 @@ static HRESULT WINAPI JpegEncoder_Frame_WriteSource(IWICBitmapFrameEncode *iface
     if (SUCCEEDED(hr))
     {
         hr = write_source(iface, pIBitmapSource, prc,
-            This->format->guid, This->format->bpp, This->width, This->height);
+            This->format->guid, This->format->bpp, FALSE,
+            This->width, This->height);
     }
 
     return hr;

dlls/windowscodecs/main.c

@@ -154,7 +154,7 @@ HRESULT configure_write_source(IWICBitmapFrameEncode *iface,
 
 HRESULT write_source(IWICBitmapFrameEncode *iface,
     IWICBitmapSource *source, const WICRect *prc,
-    const WICPixelFormatGUID *format, UINT bpp,
+    const WICPixelFormatGUID *format, UINT bpp, BOOL need_palette,
     INT width, INT height)
 {
     IWICBitmapSource *converted_source;
@@ -185,6 +185,28 @@ HRESULT write_source(IWICBitmapFrameEncode *iface,
         return E_NOTIMPL;
     }
 
+    if (need_palette)
+    {
+        IWICPalette *palette;
+
+        hr = PaletteImpl_Create(&palette);
+        if (SUCCEEDED(hr))
+        {
+            hr = IWICBitmapSource_CopyPalette(converted_source, palette);
+
+            if (SUCCEEDED(hr))
+                hr = IWICBitmapFrameEncode_SetPalette(iface, palette);
+
+            IWICPalette_Release(palette);
+        }
+
+        if (FAILED(hr))
+        {
+            IWICBitmapSource_Release(converted_source);
+            return hr;
+        }
+    }
+
     stride = (bpp * width + 7)/8;
 
     pixeldata = HeapAlloc(GetProcessHeap(), 0, stride * prc->Height);

dlls/windowscodecs/pngformat.c

@@ -1772,7 +1772,9 @@ static HRESULT WINAPI PngFrameEncode_WriteSource(IWICBitmapFrameEncode *iface,
     if (SUCCEEDED(hr))
     {
         hr = write_source(iface, pIBitmapSource, prc,
-            This->format->guid, This->format->bpp, This->width, This->height);
+            This->format->guid, This->format->bpp,
+            !This->colors && This->format->color_type == PNG_COLOR_TYPE_PALETTE,
+            This->width, This->height);
     }
 
     return hr;

dlls/windowscodecs/tests/bmpformat.c

@@ -1247,7 +1247,7 @@ static void test_writesource_palette(void)
     ok(hr == S_OK, "GetFrame error %#x\n", hr);
 
     hr = IWICBitmapFrameDecode_CopyPalette(frame_decode, palette);
-    todo_wine ok(hr == S_OK, "CopyPalette error %#x\n", hr);
+    ok(hr == S_OK, "CopyPalette error %#x\n", hr);
 
     hr = IWICPalette_GetColors(palette, 2, result_palette, &result_colors);
     ok(hr == S_OK, "GetColors error %#x\n", hr);

dlls/windowscodecs/tiffformat.c

@@ -1769,7 +1769,9 @@ static HRESULT WINAPI TiffFrameEncode_WriteSource(IWICBitmapFrameEncode *iface,
     if (SUCCEEDED(hr))
     {
         hr = write_source(iface, pIBitmapSource, prc,
-            This->format->guid, This->format->bpp, This->width, This->height);
+            This->format->guid, This->format->bpp,
+            !This->colors && This->format->bpp <= 8 && !IsEqualGUID(This->format->guid, &GUID_WICPixelFormatBlackWhite),
+            This->width, This->height);
     }
 
     return hr;

dlls/windowscodecs/wincodecs_private.h

@@ -174,7 +174,7 @@ extern HRESULT configure_write_source(IWICBitmapFrameEncode *iface,
 
 extern HRESULT write_source(IWICBitmapFrameEncode *iface,
     IWICBitmapSource *source, const WICRect *prc,
-    const WICPixelFormatGUID *format, UINT bpp,
+    const WICPixelFormatGUID *format, UINT bpp, BOOL need_palette,
     INT width, INT height) DECLSPEC_HIDDEN;
 
 extern void reverse_bgr8(UINT bytesperpixel, LPBYTE bits, UINT width, UINT height, INT stride) DECLSPEC_HIDDEN;