Update MPEG-2 and H.264 encode elements to cope with the new core
libgstvaapi properties API. i.e. all configurable properties are now
directly handled at the GstVaapiEncoder level.
Besides, this also makes sure to not use or modify the GstVaapiEncoder
private definitions directly. Private data need to remain private.
https://bugzilla.gnome.org/show_bug.cgi?id=719529
Constify pointers wherever possible. Drop unused variables, and use
consistent variable names. Fix gst_vaapiencode_h264_allocate_buffer()
to correctly report errors, especially when in-place conversion from
bytestream to avcC format failed.
Move "rate-control" mode and "bitrate" properties to the GstVaapiEncode
base class. The actual range of supported rate control modes is currently
implemented as a plug-in element hook. This ought to be determined from
the GstVaapiEncoder object instead, i.e. from libgstvaapi.
Add a GST_VAAPIENCODE_CAST() helper to avoid run-time checks against
the GObject type system. We are guaranteed to only deal with the same
plug-in element object.
Add GstVaapiEncodeH264 element object. The actual plug-in element
is called "vaapiencode_h264".
Valid properties:
- rate-control: rate control mode (default: none)
- bitrate: desired bitrate in kbps (default: auto-calculated)
- key-period: maximal distance between two key frames (default: 30)
- num-slices: number of slices per frame (default: 1)
- max-bframes: number of B-frames between I and P (default: 0)
- min-qp: minimal quantizer (default: 1)
- init-qp: initial quantizer (default: 26)
Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>
