Change VkFormat in Vulkan Texture Import

[ABest2]

I have modified the Vulkan Texture Import example.

https://doc.qt.io/qt-6/qtquick-scenegraph-vulkantextureimport-example.html

It is working well but I only need to render in grayscale so I don't need the VK_FORMAT_R8G8B8A8_UNORM which is the default required VkFormat for import. Is there a method to initialize the view to use a different format such as VK_FORMAT_R8_UNORM? This would reduce the quantity of data which needs to be copied.