This is for the bidir-pred experiment. Previously the length of the
bi-predictive frame group interval is fixed at 2, i.e. one
bi-predictive frame may be inserted every other frame. This patch
makes the length adjustable, i.e. any positive number may be
specified, but the use of the backward ref will be turned off if the
bi-predictive frame group interval is larger than the golden frame
group.
Further, an additional rate factor level has been added:
INTER_LOW
, which applies to LAST_BIPRED_UPDATE frames that are not used as
references.
Change-Id: I5514d34a64dd486bbb5756c2d0612946f598a789
Major parts have been implemented as follows:
(1) Added BRF_UPDATE, LASTNRF_UPDATE, and NRF_UPDATE in firstpass.c;
(2) Added the handling for the scenario of
"cpi->common.show_existing_frame == 1" at the encoder;
(3) Added a new reference frame of BWDREF_FRAME;
(4) Have bwd-ref work with upsampled references.
Note that when the experiment of "ext_refs" turned on, this experiment
will be turned off automatically currently.
RD performance in Overall PSNR has been improved, compared against the
VP10 baseline:
lowres: Avg -3.312; BDRate -3.154
derflr: Avg -1.927; BDRate -1.176
midres: Avg -2.149; BDRate -2.001
hdres : Avg -0.567; BDRate -0.588
Change-Id: I4c06ff51cc20194bffbd4d2346e57ba3dcf6b62c
For testing implemented a fixed pattern and delta, 1 pass,
fixed Q, low delay mode.
This has not in any way been tuned or optimized.
Change-Id: Icf9b57c3bb16cc5c0726d5229009212af36eb6d9
Spatial/temporal svc code was removed. Verified using Borg test,
and the results before and after the change are matching.
Change-Id: I4c2ee5cd560428e3e50be02e57e5871ef4246390