This commit replaces the 16x16 2D-DCT transform with Hadamard
transform for RTC coding mode. It reduces the CPU cycles cost
on 16x16 transform by 5X. Overall it makes the speed -6 encoding
speed 1.5% faster without compromise on compression performance.
Change-Id: If6c993831dc4c678d841edc804ff395ed37f2a1b
This commit makes the encoder to select between SATD/variance as
metric for mode decision. It also allows to account chroma
component costs for mode decision as well. The overall encoding
time increase as compared to variance based mode selection is about
15% for speed -6. The compression performance is on average 2.2%
better than variance based approach, with about 5% compression
performance gains for hard clips (e.g., jimredvga, nikas720p, and
mmmoving) at lower bit-rate range.
Change-Id: I4d04a31d36f4fcb3f5f491dacd6e7fe44cb9d815
This commit uses Hadamard transform based rate-distortion cost
estimate for rtc coding mode decision. It improves the compression
performance of speed -6 for many hard clips at lower bit-rates.
For example, 5.5% for jimredvga, 6.7% for mmmoving, 6.1% for
niklas720p. This will introduce extra encoding cycle costs at
this point.
Change-Id: Iaf70634fa2417a705ee29f2456175b981db3d375
Metrics on RTC set go down by ~1.5% on average.
Key frame encoding time goes down by factor of ~5.
Change-Id: Ia83acc55848613870e5ac6efe7f3d904d877febb
To enable us to the scale-invariant motion estimation
code during mode selection, each of the reference
buffers is scaled to match the size of the frame
being encoded.
This fix ensures that a unit scaling factor is used in
this case rather than the one calculated assuming that
the reference frame is not scaled.
Change-Id: Id9a5c85dad402f3a7cc7ea9f30f204edad080ebf
Set the GF group adaptive max Q compile flag to 1 by default.
This change has a quite big visual impact in some clips and also
contributes to tighter rate control.
For short test clips that have consistent content the impact is
quite small on metrics but for more varied long form clips there is
a drop in overal psnr but a sharp rise in average psnr caused by
greater expenditure on some easier sections and tighter rate clipping
in hard sections.
In chunck'ed encodes some of the effect will already be present due
to the independent rate control in each chunk but this change takes
the control down to a smaller scale.
yt hd +10.67%, - 3.77%, -1.56%
yt +9.654%, - 3.6%, - 1.82%
std hd +0.25%, -0.85%, -0.42%
derf +0.25%, - 1.1%. - 0.87%
Change-Id: Ibbc39b800d99d053939f4c6712d715124082843e
1. skip near if it is same as nearest
2. correct rounding for converting mv to fullpel position
3. update pred_mv_sad after new mv search.
Overall .1%~.25% compression gains on rtc set for speed 5, 6, 7, 8.
Change-Id: Ic300ca53f7da18073771f1bb993c58cde9deee89
Revised adjustment for rd based on source complexity.
Two cases:
1) Bias against low variance intra predictors
when the actual source variance is higher.
2) When the source variance is very low to give a slight
bias against predictors that might introduce false texture
or features.
The impact on metrics of this change across the test sets is
small and mixed.
derf -0.073%, -0.049%, -0.291%
std hd -0.093%, -0.1%, -0.557%
yt +0.186%, +0.04%, - 0.074%
ythd +0.625%, + 0.563%, +0.584%
Medium to strong psycho-visual improvements in some
problem clips.
This feature and intra weight on GF group length now
turned on by default.
Change-Id: Idefc8b633a7b7bc56c42dbe19f6b2f872d73851e
