Introduce new decoding process whereby a GstVideoCodecFrame is created
first. Next, input stream buffers are accumulated into a GstAdapter,
that is then passed to the _parse() function. The GstVaapiDecoder object
accumulates all parsed units and when a complete frame or field is
detected, that GstVideoCodecFrame is passed to the _decode() function.
Ultimately, the caller receives a GstVaapiSurfaceProxy if decoding
process was successful.
The start_frame() hook is called prior to traversing all decode-units
for decoding. The unit argument represents the first slice in the frame.
Some codecs (e.g. H.264) need to wait for the first slice in order to
determine the actual VA context parameters.
Split decoding process into two steps: (i) parse incoming bitstreams
into simple decoder-units until the frame or field is complete; and
(ii) decode the whole frame or field at once.
This is an ABI change.
GstVaapiSurfaceProxy does not use any particular functionality from
GObject. Actually, it only needs a basic object type with reference
counting.
This is an API and ABI change.
Improve the semantics for gst_vaapi_decoder_put_buffer() when an empty
buffer is passed on. An empty buffer is a buffer with a NULL data pointer
or with a size equals to zero. In this case, that buffer is simply
skipped and the function returns TRUE. A NULL buffer argument still
marks the end-of-stream.
Reset, i.e. destroy then create, the decoder in _setcaps() handler only
if the underlying codec type actually changed. This makes it possible
to be more tolerant with certain MPEG-2 streams that get parsed to
form caps that are compatible with the previous state but minor changes
to "codec-data".
Use g_object_notify_by_pspec() instead of g_object_notify() so that to
avoid a property name lookup. i.e. this makes notifications faster to
the `vaapidecode' element.
Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>
Drop obsolete gst_vaapi_decoder_push_surface() that was no longer used.
Change gst_vaapi_decoder_push_surface_proxy() semantics to assume PTS
is already set correctly and reference count increased, if necessary.
The new API simplifies a lot reference counting and makes it more
flexible for future additions/changes. The GstVaapiCodecInfo is
also gone. Rather, new helper macros are provided to allocate
picture, slice and quantization matrix parameter buffers.
Under some circumstances, we could have leaked a surface, thus not
releasing it to the pool of available surfaces in the VA context.
The strategy is now to use a proxy earlier and automatically ref/unref
whenever necessary. In particular, during the lifetime needed for FFmpeg.
