d3d11: Move GstD3D11Converter to gst-libs
examples: d3d11: Add GstD3D11Converter example
An example to demonstrate color space conversion, rescale and flip/rotation
using GstD3D11Converter
d3d11: Move GstD3D11Converter to gst-libs
The object is equivalent to GstVideoConverter but for D3D11.
Application can use this object directly for various conversions,
such as color space conversion, rescale, crop and flip/rotation.
d3d11format: Move DXGI color space mapping method to gst-libs
Expose color space mapping method to public so that application
can configure GstCaps or GstVideoInfo using DXGI color space
Edited by Seungha Yang