He Junyan ee7677211a libs: encoder: h265: Deprecate the low-delay-b property. ... In HEVC, P and B definitions are different from AVC: P frames have just one reference list and so 1 MV, while B frames have two reference lists and so 2 MVs. No matter B or P, ist reference lists can contain forward/backward reference. So P and B can both have bi-directions dependency, the difference is just their reference list number (i.e. MV number). This is different from the AVC. The *low delay b mode* refers to a special HEVC mode, in which the stream just contain I and B frames, without P frames, and all B frames only have forward direction dependencies (i.e. all inter frames have 2 reference lists but no backward reference in both lists). This is similar to AVC I/P mode, but changing the P to the forward dependent B. The `low-delay-b` property is now just used to simply convert all P frames to B frames when driver does not support P frames (so both reference lists have the same references frames). This is a little different from the meaning of low delay b mode (the two ref lists may have the different reference frames). And the driver now can report whether it supports P frames correctly, so there is no need to use this property and deprecate it. Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer-vaapi/-/merge_requests/284>		2020-07-27 16:32:49 +02:00
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vaapi	libs: encoder: h265: Deprecate the low-delay-b property.	2020-07-27 16:32:49 +02:00
meson.build	libs: remove gstbitwriter	2018-05-06 17:29:45 +02:00