Refactor the GstVaapiCodedBuffer APIs so that to more clearly separate
public and private interfaces. Besides, the map/unmap APIs should not
be exposed as is but appropriate accessors should be provided instead.
* GstVaapiCodedBuffer: VA coded buffer abstraction
- gst_vaapi_coded_buffer_get_size(): get coded buffer size.
- gst_vaapi_coded_buffer_copy_into(): copy coded buffer into GstBuffer
* GstVaapiCodedBufferPool: pool of VA coded buffer objects
- gst_vaapi_coded_buffer_pool_new(): create a pool of coded buffers of
the specified max size, and bound to the supplied encoder
* GstVaapiCodedBufferProxy: pool-allocated VA coded buffer object proxy
- gst_vaapi_coded_buffer_proxy_new_from_pool(): create coded buf from pool
- gst_vaapi_coded_buffer_proxy_get_buffer(): get underlying coded buffer
- gst_vaapi_coded_buffer_proxy_get_buffer_size(): get coded buffer size
Rationale: more optimized transfer functions might be provided in the
future, thus rendering the map/unmap mechanism obsolete or sub-optimal.
https://bugzilla.gnome.org/show_bug.cgi?id=719775
Optimize gst_vaapiencode_handle_frame() to avoid extra memory allocation,
and in particular the GstVaapiEncObjUserData object. i.e. directly use
the VA surface proxy from the source buffer. This also makes the user
data attached to the GstVideoCodecFrame more consistent between both
the decoder and encoder plug-in elements.
Add initial API for video encoding: only basic interfaces and small
encoder objects are implemented so far.
Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>