VBR rate control can become very noisy for the last few frames.
If there are a few bits to spare or a small overshoot then the
target rate and hence quantizer may start to fluctuate wildly.
This patch prevents further adjustment of the active Q limits for
the last few frames.
Patch also removes some redundant variables and makes one small bug fix.
Change-Id: Ic167831bec79acc9f0d7e4698bcc4bb188840c45
Small changes to the default zero bin and rounding tables.
Though the tables are currently the same for the Y1 and Y2 cases
I have left them as separate tables in case we want to tune this later.
There is now some adjustment of the zbin based on the prediction mode.
Previously this was restricted to an adjustment for gf/arf 0,0 MV.
The exact quantizer now marginal outperforms and is the default.
The overall average gain is about 0.5%
Change-Id: I5e4353f3d5326dde4e86823684b236a1e9ea7f47
Change Ice204e86 identified a problem with bitrate undershoot due to
low precision in the timestamps passed to the library. This patch
takes a different approach by calculating the duration of this frame
and passing it to the library, rather than using a fixed duration
and letting the library average it out with higher precision
timestamps. This part of the fix only applies to vpxenc.
This patch also attempts to fix the problem for generic applications
that may have made the same mistake vpxenc did. Instead of
calculating this frame's duration by the difference of this frame's
and the last frame's start time, we use the end times instead. This
allows the framerate calculation to scavenge "unclaimed" time from
the last frame. For instance:
start | end | calculated duration
======+=======+====================
0ms 33ms 33ms
33ms 66ms 33ms
66ms 99ms 33ms
100ms 133ms 34ms
Change-Id: I92be4b3518e0bd530e97f90e69e75330a4c413fc
NEON has optimized 16x16 half-pixel variance functions, but they
were not part of the RTCD framework. Add these functions to RTCD,
so that other platforms can make use of this optimization in the
future and special-case ARM code can be removed.
A number of functions were taking two variance functions as
parameters. These functions were changed to take a single
parameter, a pointer to a struct containing all the variance
functions for that block size. This provides additional flexibility
for calling additional variance functions (the half-pixel special
case, for example) and by initializing the table for all block sizes,
we don't have to construct this function pointer table for each
macroblock.
Change-Id: I78289ff36b2715f9a7aa04d5f6fbe3d23acdc29c
Most of the code that actually uses these matrices indexes them as
if they were a single contiguous array, and coverity produces
reports about the resulting accesses that overflow the static
bounds of the first row.
This is perfectly legal in C, but converting them to actual [16]
arrays should eliminate the report, and removes a good deal of
extraneous indexing and address operators from the code.
Change-Id: Ibda479e2232b3e51f9edf3b355b8640520fdbf23
The first implementation of the firstpass motion map for motion
compensated temporal filtering created a file, fpmotionmap.stt,
in the current working directory. This was not safe for multiple
encoder instances. This patch merges this data into the first pass
stats packet interface, so that it is handled like the other
(numerical) firstpass stats.
The new stats packet is defined as follows:
Numerical Stats (16 doubles) -- 128 bytes
Motion Map -- 1 byte / Macroblock
Padding -- to align packet to 8 bytes
The fpmotionmap.stt file can still be generated for debugging
purposes in the same way that the textual version of the stats
are available (defining OUTPUT_FPF in firstpass.c)
Change-Id: I083ffbfd95e7d6a42bb4039ba0e81f678c8183ca
when a subsequent frame is encoded as an alt reference frame, it is
unlikely that any mb in current frame will be used as reference for
future frames, so we can enable quantization optimization even when
the RD constant is slightly rate-biased. The change has an overall
benefit between 0.1% to 0.2% bit savings on the test sets based on
vpxssim scores.
Change-Id: I9aa7bc5cd573ea84e3ee655d2834c18c4460ceea
This uses MB variance to change the RDO weight for mode decision
and quantization.
Activity is normalized against the average for the frame, which is
currently tracked using feed-forward statistics.
This could also be used to adjust the quantizer for the entire
frame, but that requires more extensive rate control changes.
This does not yet attempt to adapt the quantizer within the frame,
but the signaling cost means that will likely only be useful at
very high rates.
Change-Id: I26cd7c755cac3ff33cfe0688b1da50b2b87b9c93
This is just eliminating some cruft.
Although a number of variables are declared only when INTRARDOPT
is defined, they are used elsewhere without that protection, and
no longer just for intra RDO.
The intra_rd_opt flag was hard-coded to 1 and never checked.
Change-Id: I83a81554ecee8053e7b4ccd8aa04e18fa60f8e4f
Modified AltRef temporal filter to adapt filter length based
on macroblock coding modes selected during first-pass
encode.
Also added sub-pixel motion compensation to the AltRef
filter.
-Updates by making use of spatial correlation.
-Checks if the segment_id is same as above or left context and encodes only the update to the map instead of updating individual segment_ids.
Change-Id: Ib861df97e8aa2b37516219eeddcdbaf552b6a249
Changes 'The VP8 project' to 'The WebM project', for consistency
with other webmproject.org repositories.
Fixes issue #97.
Change-Id: I37c13ed5fbdb9d334ceef71c6350e9febed9bbba
In two pass encodes, the calculation of the number of bits
allocated to a KF group had the potential to overflow for high data
rates if the interval is very long.
We observed the problem in one test clip where there was one
section where there was an 8000 frame gap between key frames.
Change-Id: Ic48eb86271775d7573b4afd166b567b64f25b787
This replaces the approximate division-by-multiplication in the
quantizer with an exact one that costs just one add and one
shift extra.
The asm versions have not been updated in this patch, and thus
have been disabled, since the new method requires different
multipliers which are not compatible with the old method.
Change-Id: I53ac887af0f969d906e464c88b1f4be69c6b1206
When the license headers were updated, they accidentally contained
trailing whitespace, so unfortunately we have to touch all the files
again.
Change-Id: I236c05fade06589e417179c0444cb39b09e4200d
This patch addresses issue #79, which is a regression since commit
28de670 "Fix RD bug." If the coded error value is zero, the iiratio
calculation effectively multiplies by 1000000 by the
DOUBLE_DIVIDE_CHECK macro. This can result in a value larger than
INT_MAX, giving a negative ratio. Since the error values are
conceptually unsigned (though they're stored in a double) this patch
makes the iiratio values unsigned, which allows the clamping to work
as expected.
This renames the vpx_codec/ directory to vpx/, to allow applications
to more consistently reference these includes with the vpx/ prefix.
This allows the includes to be installed in /usr/local/include/vpx
rather than polluting the system includes directory with an
excessive number of includes.
Change-Id: I7b0652a20543d93f38f421c60b0bbccde4d61b4f
