Re: [PATCH 3/3] windowscodecs: Use source palette if it wasn't specified earlier for PNG frame

[Dmitry Timoshkov]

Nikolay Sivov  wrote:
> @@ -1765,6 +1765,18 @@ static HRESULT WINAPI PngFrameEncode_WriteSource(IWICBitmapFrameEncode *iface,
>  if (SUCCEEDED(hr))
>  {
> -
>    if (This->colors == 0)
> -
>    {
> -
>        IWICPalette *palette;
> -
> -
>        if (SUCCEEDED(PaletteImpl_Create(&palette)))
> -
>        {
> -
>            if (SUCCEEDED(IWICBitmapSource_CopyPalette(pIBitmapSource, palette)))
> -
>                IWICBitmapFrameEncode_SetPalette(iface, palette);
> -
>            IWICPalette_Release(palette);
> -
>        }
> -
>    }
> -
>    hr = write_source(iface, pIBitmapSource, prc,
>        This->format->guid, This->format->bpp, This->width, This->height);
> }

What is this for? It looks like a workaround for a WIC converter bug.
I'd like to see a test case for this behaviour.