This patch collects the twopass specific memebers of VP8_COMP into a
dedicated struct. This is a first step towards isolating the two pass
rate control and aids readability by decorating these variables with
the 'twopass.' namespace. This makes it clear to the reader in what
contexts the variable will be valid, and is a hint that a section of
code might be a good candidate to move to firstpass.c in later
refactoring. There likely will be other rate control modes that need
their own specific data as well.
This notation is probably overly verbose in firstpass.c, so an
alternative would be to access this struct through a pointer like
'rc->' instead of 'cpi->firstpass.' in that file. Feel free to make
a review comment to that effect if you prefer.
Change-Id: I0ab8254647cb4b493a77c16b5d236d0d4a94ca4d
The compiler produces better assembly when using int_mv
for assignments. The compiler shifts and ors the two 16bit
values when assigning MV.
Change-Id: I52ce4bc2bfbfaf3f1151204b2f21e1e0654f960f
This patch cleans up the source buffer storage and copy mechanism to
allow access through a standard push/pop/peek interface. This approach
also avoids an extra copy in the case where the source is not a
multiple of 16, fixing issue #102.
Change-Id: I05808c39f5743625cb4c7af54cc841b9b10fdbd9
MV sad cost error is only used in full-pixel motion search,
which only need full-pixel resolution instead of quarter-pixel
resolution. This change reduced mvsadcost table size, and
removed unneccessary pamameter passing since this table is
constant once it is generated.
Change-Id: I9f931e55f6abc3c99011321f1dfb2f3562e6f6b0
A large number of functions were defined with external linkage, even
though they were only used from within one file. This patch changes
their linkage to static and removes the vp8_ prefix from their names,
which should make it more obvious to the reader that the function is
contained within the current translation unit. Functions that were
not referenced were removed.
These symbols were identified by:
$ nm -A libvpx.a | sort -k3 | uniq -c -f2 | grep ' [A-Z] ' \
| sort | grep '^ *1 '
Change-Id: I59609f58ab65312012c047036ae1e0634f795779
The firstpass motion map consists of an 8-bit flag for
each MB indicating how strongly the firstpass code
believes it should be filtered during the second pass
ARNR filtering.
For long or large format material the motion map can
become extremely large and hamper the operation of
the encoding process.
This change removes the motion map altogether, leaving
the second pass to rely on the magnitude of the motion
compensated error to determine the filter weight to
use for the MB during ARNR filtering.
Tests on the derf set indicate that the effect of this
change is neutral, with some small wins and losses. The
motion map has therefore been removed based on
a cost/benefit evaluation.
Change-Id: I53e07d236f5ce09a6f0c54e7c4ffbb490fb870f6
The previous calculation of macroblock count (w*h)/256
is not correct when the width/height are not multiples of
16. Use the precalculated macroblock count from
cpi->common instead. This manifested itself as a divide
by zero when the number of pixels was less than 256.
num_mbs updated in estimate_max_q, estimate_q,
estimate_kf_group_q, and estimate_cq
Change-Id: I92ff98587864c801b1ee5485cfead964673a9973
GCC 4.5 and 4.6 both issue a warning about the multi-line format
string introduced in bc9c30a0, which also changed the whitespace
in the associated stt file by line-wrapping the long format string.
Instead, use multiple string constants, which the compiler will
concatenate. This maintains the original formatting, but remains
legible within the standard line length.
Change-Id: I27c9f92d46be82d408105a3a4091f145f677e00e
In some cases where clips have been encoded with
borders (eg. some wide-screen content where there is a
border top and bottom and slide shows containing portrait
format photographs (border left and right)) key frames were
not being correctly detected.
The new code looks to measure cases where a portion of
the image can be coded equally easily using intra or inter
modes and where the resulting error score is also very low.
These "neutral" areas are then discounted in the key frame
detection code.
Change-Id: I00c3e8230772b8213cdc08020e1990cf83b780d8
This code extends what was previously done for GFs, to pick
cases where insertion of a key frame after a fade (or other
transition or complex motion) followed by a still section, will
be beneficial and will reduce the number of forced key frames.
Change-Id: If8bca00457f0d5f83dc3318a587f61c17d90f135
When the modified_error_left accumulator exceeds INT_MAX, an incorrect
cast to int resulted in a negative value, causing the rate control to
allocate no bits to that keyframe group, leading to severe undershoot
and subsequent poor quality.
This error was exposed by the recent change to the rolling target and
actual spend accumulators in commit 305be4e4 which fixed them to
actually calculate the average value rather than be re-initialized
on every frame to the average per-frame bitrate. When this bug was
triggered, the target bitrate could be 0, so the rolling target
becomes small, which causes the undershoot. The code prior to 305be4e4
did not exhibit this behavior because the rolling target was always
set to a reasonable value and was independent of the actual target
bitrate. With this patch, the actual target bitrate is calculated
correctly, and the rate control tracks as expected.
This cast was likely added to silence a compiler warning on a comparison
between a double (modified_error_left) and an int (0). Instead, this
patch removes the cast and changes the comparison to be against 0.0,
which should prevent the warning from reoccuring.
This fixes issue #289. Special thanks to gnafu for his efforts in
reporting and debugging this fix.
Change-Id: Ie5cc1a7b516c578a76c3a50c892a6f04a11621fe
This fixes an overflow problem in the frame error accumulators.
The overflow condition is extreme but did trigger when Frank B.
coded some high motion interlaced HD content.
The observed effect was a catastrophic breakdown of the rate
control leading to massive undershoot and poor bit allocation.
All the error values should really be unsigned but I will look at this
separately.
Change-Id: I9745f5c5ca2783620426b66b568b2088b579151f
Improved the performance of the first pass only
(~6% on 720p test clip) by making use of LUT instead of the
float calculations. Might try a SIMD version later.
Also started to make use of int_mv instead of
MV.
Change-Id: If2a217c7d6b59cd2c25c5553e0ca7e0502403af8
Commit 336aa0b7da incorrectly
declared current_pos as and int, when it should have been
a FIRSTPASS_STATS pointer.
Change-Id: I0a51c7a86ebba8546c95dd5d9d1c1143d4613e40
The old 2 pass code estimated error distribution when coding a
forced (by interval) key frame. The result of this was that in some
cases, when allocating bits at the GF group level within a KF
group there was either a glut of bits or starvation of bits at the end
of the KF group.
Added code to rescan and get the correct data once the position of
a forced key frame has been determined.
Change-Id: I0c811675ef3f9e4109d14bd049d7641682ffcf11
Added code to scan ahead a few frames when we see what
we think is a static scene in the two pass GF loop to see if the
conditions persist.
Moved calculation of decay rate out into a fuunction.
Change-Id: I6e9c67e01ec9f555144deafc8ae67ef25bffb449
These changes are specifically targeted at fade transitions to
static scenes. Here we want to place a GF/ARF immediately
after the fade and prevent an ARF just before the fade.
Also some code lines and comment lines shortened to 80 chars
while I was there.
Change-Id: Iefdc09a4fa7b265048fc017246b73e138693950f
In both vp8_find_next_key_frame and define_gf_group,
motion_pct was initialised at the top of the loop before
next_frame stats had been read in.
This fix sets motion_pct after next_frame stats have
been read.
Change-Id: I8c0bebf372ef8aa97b97fd35b42973d1d831ee73
Incorrect value loop_decay_rate used in GF loop.
The intent was to test the cumulative value decay_accumulator.
Change-Id: I62928c63eb09f4f6936a45ebd1c23784d1c9681b
This code fixes a bug in the calculation of
the minimum Q for alt ref frames.
It also allows an extended gf/arf interval for sections
of clips that completely static (or nearly so).
Change-Id: I1a21aaa16d4f0578e5f99b13bebd78d59403c73b
Where a key frame occurs because of a minimum interval
selected by the user, then these forced key frames ideally need
to be more closely matched in quality to the surrounding frame.
Change-Id: Ia55b1f047e77dc7fbd78379c45869554f25b3df7
Further experiment with restriction of the Q range.
This uses the average non KF/GF/ARF quantizer, instead
of just relying on the initial value. It is not such a strong constraint
but there may be a reduced risk of rate misses.
Change-Id: I424fe782a37a2f4e18c70805e240db55bfaa25ec
The merge includes hooks to for CQ mode and other code
changes merged from the test branch.
CQ mode attempts to maintain a more stable quantizer within a clip
whilst also trying to adhere to a guidline maximum bitrate.
The existing target data rate parameter is used to specify the
guideline maximum bitrate.
A new parameter allows the user to specify a target CQ level.
For normal (non kf/gf/arf) frames, the quantizer will not drop BELOW the
user specified value (0-63). However, in some cases the encoder may
choose to impose a target CQ that is above that specified by the user,
if it estimates that consistent use of the target value is not compatible
with guideline maximum bitrate.
Change-Id: I2221f9eecae8cc3c431d36caf83503941b25e4c1
In two pass encoding each frame is given an active
Q range to work with. This change limits how much this
Q range can be altered over time from the initial estimate
made for the clip as a whole.
There is some danger this could lead to overshoot or undershoot
in some corner cases but it helps considerably in regard to
clips where either there is a glut or famine of bits in some sections,
particularly near the end of a clip.
Change-Id: I34fcd1af31d2ee3d5444f93e334645254043026e
Calculate a minimum intra value to be used in determining the
IIratio scores used in two pass, second pass.
This is to make sure sections that are low complexity" in the
intra domain are still boosted appropriately for KF/GF/ARF.
For now I have commented out the Q based adjustment of
KF boost.
Change-Id: I15deb09c5bd9b53180a2ddd3e5f575b2aba244b3
Add vp8_mv_pred() to better predict starting MV for NEWMV
mode in vp8_rd_pick_inter_mode(). Set different search
ranges according to MV prediction accuracy, which improves
encoder performance without hurting the quality. Also,
as Yaowu suggested, using diamond search result as full
search starting point and therefore adjusting(reducing)
full search range helps the performance.
Change-Id: Ie4a3c8df87e697c1f4f6e2ddb693766bba1b77b6
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
This eliminates a large set of warnings exposed by the Mozilla build
system (Use of C++ comments in ISO C90 source, commas at the end of
enum lists, a couple incomplete initializers, and signed/unsigned
comparisons).
It also eliminates many (but not all) of the warnings expose by newer
GCC versions and _FORTIFY_SOURCE (e.g., calling fread and fwrite
without checking the return values).
There are a few spurious warnings left on my system:
../vp8/encoder/encodemb.c:274:9: warning: 'sz' may be used
uninitialized in this function
gcc seems to be unable to figure out that the value shortcut doesn't
change between the two if blocks that test it here.
../vp8/encoder/onyx_if.c:5314:5: warning: comparison of unsigned
expression >= 0 is always true
../vp8/encoder/onyx_if.c:5319:5: warning: comparison of unsigned
expression >= 0 is always true
This is true, so far as it goes, but it's comparing against an enum, and the C
standard does not mandate that enums be unsigned, so the checks can't be
removed.
Change-Id: Iaf689ae3e3d0ddc5ade00faa474debe73b8d3395
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
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
This code adjust the impact of the amount and speed of motion
on GF and KF boost.
Sections with lots of slow motion will tend to have a
somewhat bigger boost and sections with fast motion may
have less.
There is a knock on effect to the selection of the active
quantizer range.
This will likely require further tuning but helps with a couple
of particularly bad edge cases.
Change-Id: Ic2449cda7305672b69acf42fc0a845b77ac98d40
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.
When ARFs are enabled in non-lagged compress modes, the GF interval
was being reset to zero. Non-lagged ARF updates were enabled in commit
63ccfbd, but this incorrect GF interval caused a quality regression.
Change-Id: I615c3b493f4ce2127044f4e68d0bcb07d6b730c3
Changes 'The VP8 project' to 'The WebM project', for consistency
with other webmproject.org repositories.
Fixes issue #97.
Change-Id: I37c13ed5fbdb9d334ceef71c6350e9febed9bbba
Moved partition_bmi and partition_count out of MB_MODE_INFO and
placed into MACROBLOCK. Also reduced the size of other members
of the MB_MODE_INFO struct. For 1080p, the memory was reduced
by 1,209,516 bytes. The decoder performance appeared to improve
by 3% for the clip used.
Note: The main goal for this change is to improve the decoder
performance. The encoder will be revisited at a later date for
further structure cleanup.
Change-Id: I4733621292ee9cc3fffa4046cb3fd4d99bd14613
These changes improve the behaviour of the code with
forced key frames sent in by a calling application.
The sizing of the frames is still suboptimal for two pass in
particular but the behaviour is much better than it was.
Change-Id: I35fae610c67688ccc69d11f385e87dfc884e65a1
