Putting appropriate check to open_output_file() and close_output_file().
Before that the output file has been opened twice during two-pass encoding.
Change-Id: I290cecf00513d6a31ca3f45bc20fef7efcb10190
- Add command line args that allow display of warnings without prompting
for user input.
- Extend warning code to make it somewhat scalable.
Change-Id: I2bad8f9315f6eed120c2e1bbe0a2a5ede15fbf35
The idea here is to allow "in frame" adjustment of the final Q
value used to encode each SB64, using segmentation.
There is also adjustment of the rd mult in regions of overspend.
Activated using aq_mode=2
Change-Id: I2f140cd898c9f877c32cd6d2e667f5e11ada4b1c
- Rename the struct to VpxEncoderConfig.
- The idea behind this is to enable checking the global settings against
stream specific settings in source files other than vpxenc.c.
Change-Id: Ic736cbb714845b9466acb34671780d65b83ad1a8
- Move IVF reading support into ivfdec.c and ivfdec.h
- Move IVF writing support into ivfenc.c and ivfenc.h
- Removed IVF writing code from the SVC example in favor of ivfenc.
Change-Id: I70adf6240d0320fdd232d8546ed573f0f68dd793
This is mainly a clean up patchset. It moves the WebM writing support
out of vpxenc and into its own source file. Changes to tools_common and
vpxdec result from relocation of shared bits of code.
Change-Id: Iee55d3285f56e0a548f791094fb14c5ac5346a26
First pass does not produce compressed data, therefore encode/decode
match check is not initialized.
Change-Id: I1971a6747337872a850987cc70ba267bd0f1d564
Adds a new end-usage option for constant quality encoding in vpx. This
first version implemented for VP9, encodes all regular inter frames
using the quality specified in the --cq-level= option, while encoding
all key frames and golden/altref frames at a quality better than that.
The current performance on derfraw300 is +0.910% up from bitrate control,
but achieved without multiple recode loops per frame.
The decision for qp for each altref/golden/key frame will be improved
in subsequent patches based on better use of stats from the first pass.
Further, the qp for regular inter frames may also be varied around the
provided cq-level.
Change-Id: I6c4a2a68563679d60e0616ebcb11698578615fb3
Currently, the best quality mode in VP9 is not very well developed,
and unnecessarily makes the encode too slow. Hence the command line
default is changed to "good" quality. Also, the number of passes
default is changed to 2 passes as well, since 1-pass encoding is
not very efficient in VP9.
Besides, a number of VP9 defaults are set to the currently
recommended settings. With these changes, vpxenc
run with --codec=vp9 --kf-max-dist=9999 --cpu-used=0 should
work about the same as our borg results.
Note when the --cpu-used=0 option is dropped there will be a slight
difference in the output, because of a difference in the cpu-used
value for the first pass. Specifically, the default when unspecified
is to use cpu_used=1 for the first pass and cpu_used=0 for the
second pass. But when specified, both passes will use the cpu-used
value specified.
Note that this also changes the default for VP8 as being "good"
but other options stay unchanged.
Change-Id: Ib23c1a05ae2f36ee076c0e34403efbda518c5066
write_ivf_file_header would incorrectly skip writing the file header in
the 2nd pass, causing the initial frame header to be overwritten on
close potential causing an overly large frame header to be read and a
crash.
most likely broken since:
9e50ed7 vpxenc: initial implementation of multistream support
fixes issue #585
Change-Id: I7e863e295dd6344c33b3e9c07f9f0394ec496e7b
These files can stand in until we get proper syntax vectors. They
should provide some additional assurance against inadvertant
bitstream changes.
Change-Id: I12f6c9a5f054e30df40a7ff1f33145abf7e1d59d
Adds a new experiment CONFIG_NON420 that allows other chroma subsamplings
to be passed to the codec. This commit allows the data to be passed from
a y4m input file through vpxenc to the codec, where they're currently
rejected. Later commits will finish support for this inside the codec.
Change-Id: Ib3aac604d8cad9e24cef395fa1067f16ba7e8e43
Clamp only the motion vectors inferred from neighboring reference
macroblocks. The motion vectors obtained through motion search in
NEWMV mode are constrained during the search process, which allows
a relatively larger referencing region than the inferred mvs.
Hence further clamping the best mv provided by the motion search may
affect the efficacy of NEWMV mode.
Synchronized the decoding process. The decoded mvs in NEWMV modes
should be guaranteed to fit in the effective range. Put a mv range
clamping function there for security purpose.
This improves the coding performance of high motion sequences, e.g.,
derf set:
foreman 0.233%
husky 0.175%
icd 0.135%
mother_daughter 0.337%
pamphlet 0.561%
stdhd set:
blue_sky 0.408%
city 0.455%
also saw sunflower goes down by -0.469%.
Change-Id: I3fcbba669e56dab779857a8126a91b926e899cb5
Pick up VP8 encryption, quantization changes, and some fixes to vpxenc
Conflicts:
test/decode_test_driver.cc
test/decode_test_driver.h
test/encode_test_driver.cc
vp8/vp8cx.mk
vpxdec.c
vpxenc.c
Change-Id: I9fbcc64808ead47e22f1f22501965cc7f0c4791c
Adds an experiment to use a weighted prediction of two INTER
predictors, where the weight is one of (1/4, 3/4), (3/8, 5/8),
(1/2, 1/2), (5/8, 3/8) or (3/4, 1/4), and is chosen implicitly
based on consistency of the predictors to the already
reconstructed pixels to the top and left of the current macroblock
or superblock.
Currently the weighting is not applied to SPLITMV modes, which
default to the usual (1/2, 1/2) weighting. However the code is in
place controlled by a macro. The same weighting is used for Y and
UV components, where the weight is derived from analyzing the Y
component only.
Results (over compound inter-intra experiment)
derf: +0.18%
yt: +0.34%
hd: +0.49%
stdhd: +0.23%
The experiment suggests bigger benefit for explicitly signaled weights.
Change-Id: I5438539ff4485c5752874cd1eb078ff14bf5235a
Changing 0x00 ('') fourcc byte to 0x30 ('0'). For VP8 from
0x00385056 to 0x30385056, for VP9 from 0x00395056 to 0x30395056.
Change-Id: I26b1b603c20dd41f7aeabf8cd7893dfd5b1c8b59
This is like VP8_COPY_REFERENCE, but returns a pointer to the reference
frame rather than a copy of it. This is useful when the application
doesn't know what the size of the reference is, as is the case when
scaling is in effect.
Change-Id: I63667109f65510364d0e397ebe56217140772085
Fixes a rollover of the cx_time variable for encodes that take
over ~4200 seconds. Also enable the time estimate in first pass.
Change-Id: Ib5a98ee71bccd79a804d709cec7260651d0b7141
Scales the input of the encoder using libyuv's "box filter". Each stream
may have a different width and height specified. If the width (or
height) parameter is missing (or is explicitly set to 0) then the value
will be calculated based on the specified height (or width) and the
input file's dimensions, preserving its aspect ratio. Leaving the height
unspecified behaves similarly.
Change-Id: I700ef89ce54fb87588420a71c39c0e3e73b1a40e
Allows the user to specify whether decode errors should be fatal or not.
Also makes mismatches optionally fatal.
Change-Id: I58cff4a82f3d42f5653b91cf348a7f669377e632
Make the progress line more useful by providing per-frame updates of
processing frame rate and estimated time remaining.
Fixes issue #534.
Change-Id: Ic91551878ff4b2f5db1cedaafb588add220cfa52
Fixes a rollover of the cx_time variable for encodes that take
over ~4200 seconds. Also enable the time estimate in first pass.
Change-Id: Ib5a98ee71bccd79a804d709cec7260651d0b7141
Scales the input of the encoder using libyuv's "box filter". Each stream
may have a different width and height specified. If the width (or
height) parameter is missing (or is explicitly set to 0) then the value
will be calculated based on the specified height (or width) and the
input file's dimensions, preserving its aspect ratio. Leaving the height
unspecified behaves similarly.
Change-Id: Ic7026810b13be030826be80dc6f7fc4aaf0c35d0
This patch includes 4x4, 8x8, and 16x16 forward butterfly ADST/DCT
hybrid transform. The kernel of 4x4 ADST is sin((2k+1)*(n+1)/(2N+1)).
The kernel of 8x8/16x16 ADST is of the form sin((2k+1)*(2n+1)/4N).
Change-Id: I8f1ab3843ce32eb287ab766f92e0611e1c5cb4c1
Allows the user to specify whether decode errors should be fatal or not.
Also makes mismatches optionally fatal.
Change-Id: I58cff4a82f3d42f5653b91cf348a7f669377e632
These allow sending partial bitstream packets over the network before
encoding a complete frame is completed, thus lowering end-to-end
latency. The tile-rows are not independent.
Change-Id: I99986595cbcbff9153e2a14f49b4aa7dee4768e2
Make the progress line more useful by providing per-frame updates of
processing frame rate and estimated time remaining.
Fixes issue #534.
Change-Id: Ic91551878ff4b2f5db1cedaafb588add220cfa52
Refactor the 8x8 inverse hybrid transform. It is now consistent
with the new inverse DCT. Overall performance loss (due to the
use of this variant ADST, and the rounding errors in the butterfly
implementation) for std-hd is -0.02.
Fixed BUILD warning.
Devise a variant of the original ADST, which allows butterfly
computation structure. This new transform has kernel of the
form: sin((2k+1)*(2n+1) / (4N)). One of its butterfly structures
using floating-point multiplications was reported in Z. Wang,
"Fast algorithms for the discrete W transform and for the discrete
Fourier transform", IEEE Trans. on ASSP, 1984.
This patch includes the butterfly implementation of the inverse
ADST/DCT hybrid transform of dimension 8x8.
Change-Id: I3533cb715f749343a80b9087ce34b3e776d1581d
This patch adds column-based tiling. The idea is to make each tile
independently decodable (after reading the common frame header) and
also independendly encodable (minus within-frame cost adjustments in
the RD loop) to speed-up hardware & software en/decoders if they used
multi-threading. Column-based tiling has the added advantage (over
other tiling methods) that it minimizes realtime use-case latency,
since all threads can start encoding data as soon as the first SB-row
worth of data is available to the encoder.
There is some test code that does random tile ordering in the decoder,
to confirm that each tile is indeed independently decodable from other
tiles in the same frame. At tile edges, all contexts assume default
values (i.e. 0, 0 motion vector, no coefficients, DC intra4x4 mode),
and motion vector search and ordering do not cross tiles in the same
frame.
t log
Tile independence is not maintained between frames ATM, i.e. tile 0 of
frame 1 is free to use motion vectors that point into any tile of frame
0. We support 1 (i.e. no tiling), 2 or 4 column-tiles.
The loopfilter crosses tile boundaries. I discussed this briefly with Aki
and he says that's OK. An in-loop loopfilter would need to do some sync
between tile threads, but that shouldn't be a big issue.
Resuls: with tiling disabled, we go up slightly because of improved edge
use in the intra4x4 prediction. With 2 tiles, we lose about ~1% on derf,
~0.35% on HD and ~0.55% on STD/HD. With 4 tiles, we lose another ~1.5%
on derf ~0.77% on HD and ~0.85% on STD/HD. Most of this loss is
concentrated in the low-bitrate end of clips, and most of it is because
of the loss of edges at tile boundaries and the resulting loss of intra
predictors.
TODO:
- more tiles (perhaps allow row-based tiling also, and max. 8 tiles)?
- maybe optionally (for EC purposes), motion vectors themselves
should not cross tile edges, or we should emulate such borders as
if they were off-frame, to limit error propagation to within one
tile only. This doesn't have to be the default behaviour but could
be an optional bitstream flag.
Change-Id: I5951c3a0742a767b20bc9fb5af685d9892c2c96f
Adds a flag to disable features that would inhibit frame parallel
decoding. This includes backward adaptation and MV sorting based
on search in ref frame buffer.
Also includes some minor clean-ups.
Change-Id: I434846717a47b7bcb244b37ea670c5cdf776f14d
Visual Studio reports and error on the line
static const int bsize2 = bsize >> 1;
"error C2099: initializer is not a constant"
Also warnings on signed/unsigned mismatch
Change-Id: I76cb06f736bd9c90107a26bfb3c130ec3f6c33de
Adds an error-resilient mode where frames can be continued
to be decoded even when there are errors (due to network losses)
on a prior frame. Specifically, backward updates are turned off
and probabilities of various symbols are reset to defaults at
the beginning of each frame. Further, the last frame's mvs are
not used for the mv reference list, and the sorting of the
initial list based on search on previous frames is turned off
as well.
Also adds a test where an arbitrary set of frames are skipped
from decoding to simulate errors. The test verifies (1) that if
the error frames are droppable - i.e. frame buffer updates have
been turned off - there are no mismatch errors for the remaining
frames after the error frames; and (2) if the error-frames are non
droppable, there are not only no decoding errors but the mismatch
PSNR between the decoder's version of the post-error frames and the
encoder's version is at least 20 dB.
Change-Id: Ie6e2bcd436b1e8643270356d3a930e8989ff52a5
Various fixups to resolve issues when building vp9-preview under the more stringent
checks placed on the experimental branch.
Change-Id: I21749de83552e1e75c799003f849e6a0f1a35b07
This patch allows use of 8x8 and 4x4 ADST correctly for Intra
16x16 modes and Intra 8x8 modes when the block size selected
is smaller than the prediction mode. Also includes some cleanups
and refactoring.
Rebase.
Change-Id: Ie3257bdf07bdb9c6e9476915e3a80183c8fa005a
Tags VP9 tracks with the V_VP9 video type when writing to .webm files,
and supports decoding both from vpxdec without specifying --codec.
Change-Id: I0ef61dee06f4db2a74032b142a4b4976c51faf6e
Creates a merge between the master and experimental branches. Fixes a
number of conflicts in the build system to allow *either* VP8 or VP9
to be built. Specifically either:
$ configure --disable-vp9 $ configure --disable-vp8
--disable-unit-tests
VP9 still exports its symbols and files as VP8, so that will be
resolved in the next commit.
Unit tests are broken in VP9, but this isn't a new issue. They are
fixed upstream on origin/experimental as of this writing, but rebasing
this merge proved difficult, so will tackle that in a second merge
commit.
Change-Id: I2b7d852c18efd58d1ebc621b8041fe0260442c21
This commit adds lossless compression capability to the experimental
branch. The lossless experiment can be enabled using --enable-lossless
in configure. When the experiment is enabled, the encoder will use
lossless compression mode by command line option --lossless, and the
decoder automatically recognizes a losslessly encoded clip and decodes
accordingly.
To achieve the lossless coding, this commit has changed the following:
1. To encode at lossless mode, encoder forces the use of unit
quantizer, i.e, Q 0, where effective quantization is 1. Encoder also
disables the usage of 8x8 transform and allows only 4x4 transform;
2. At Q 0, the first order 4x4 DCT/IDCT have been switched over
to a pair of forward and inverse Walsh-Hadamard Transform
(http://goo.gl/EIsfy), with proper scaling applied to match the range
of the original 4x4 DCT/IDCT pair;
3. At Q 0, the second order remains to use the previous
walsh-hadamard transform pair. However, to maintain the reversibility
in second order transform at Q 0, scaling down is applied to first
order DC coefficients prior to forward transform, and scaling up is
applied to the second order output prior to quantization. Symmetric
upscaling and downscaling are added around inverse second order
transform;
4. At lossless mode, encoder also disables a number of minor
features to ensure no loss is introduced, these features includes:
a. Trellis quantization optimization
b. Loop filtering
c. Aggressive zero-binning, rounding and zero-bin boosting
d. Mode based zero-bin boosting
Lossless coding test was performed on all clips within the derf set,
to verify that the commit has achieved lossless compression for all
clips. The average compression ratio is around 2.57 to 1.
(http://goo.gl/dEShs)
Change-Id: Ia3aba7dd09df40dd590f93b9aba134defbc64e34
Allows building the library with the gcc -pedantic option, for improved
portabilty. In particular, this commit removes usage of C99/C++ style
single-line comments and dynamic struct initializers. This is a
continuation of the work done in commit 97b766a46, which removed most
of these warnings for decode only builds.
Change-Id: Id453d9c1d9f44cc0381b10c3869fabb0184d5966
aligned buffers improve performace. this change brings vpxenc &
vp8_scalable_patterns in line with the other examples.
Change-Id: I4cf9f3e4728b901161905dd7ccb092e774ffb15f
Rather than using the static default maximum keyframe spacing
provided by vpx_codec_enc_config_default() set the default
value to 5 times the frame rate. Five seconds is too long for
live streaming applications, but is a compromise between seek
efficiency and giving the encoder freedom to choose keyframe
locations.
The five second value is from James Zern's suggestion in
http://article.gmane.org/gmane.comp.multimedia.webm.user/2945
Change-Id: Ib7274dc248589c433c06e68ca07232e97f7ce17f
This is the first patch to add superblock (32x32) coding
order capabilities. It does not yet do any mode selection
at the SB level, that will follow in a further patch.
This patch encodes rows of SBs rather than
MBs, each SB contains 2x2 MBs.
Two intra prediction modes have been disabled since they
require reconstructed data for the above-right MB which
may not have been encoded yet (e.g. for the bottom right
MB in each SB).
Results on the one test clip I have tried (720p GIPS clip)
suggest that it is somewhere around 0.2dB worse than the
baseline version, so there may be bugs.
It has been tested with no experiments enabled and with
the following 3 experiments enabled:
--enable-enhanced_interp
--enable-high_precision_mv
--enable-sixteenth_subpel_uv
in each case the decode buffer matches the recon buffer
(using "cmp" to compare the dumped/decoded frames).
Note: Testing these experiments individually created
errors.
Some problems were found with other experiments but it
is unclear what state these experiments are in:
--enable-comp_intra_pred
--enable-newentropy
--enable-uvintra
This code has not been extensively tested yet, so there
is every likelihood that further bugs remain. I also
intend to do some code cleanup & refactoring in tandem
with the next patch that adds the 32x32 modes.
Change-Id: I1eba7f740a70b3510df58db53464535ef881b4d9
The commit added a new command line option --test-decode to vpxenc.
The option enables encoder to decode compressed frames and test recon
buffers from the decode against those from encode for mismatch.
There are a few limitations on this option currently, one of them
being the match test is not done on a number of lagged frames at
the end of an encoding.
Change-Id: I80c29b46dcdcea9f48107a506b235743068862fe
this commit added a command line option to skip first n frames from
input file to facilitate debugging and testing.
Change-Id: I4ffc5f85fa7e193ea4bdee08cb236717de8beef1
The maximum psnr has a marginal impact on the overall output in high
quality encodings, the change will make sure the psnr output to be
consistent with encoder internal stats.
Change-Id: I35cf2f85008ec127a7d91c9eb69fa7811798ae32
Propagate debug setting to the EBML struct. When writing the application
name, this allows us to strip the version code and keep the output
metadata static.
Change-Id: I8e06c6abd743bedbff5af6242bbdae5d55754538
When we do 2-pass encoding, elapsed time is accumulated through
whole 2-pass process, which gives incorrect time and fps results
for second pass. This change fixed that by resetting the time
accumulator for second pass.
Change-Id: Ie6cbf0d0e66e6874e7071305e253c6267529cf20
Produce the token partitions on-the-fly, while processing each MB.
Context is updated at the beginning of each frame based on the
previoud frame's counters. Optimally encoder outputs partitions in
separate buffers. For frame based output, partitions are concatenated
internally.
Limitations:
- enabled just in combination with realtime-only mode
- number of encoding threads has to be equal or less than the
number of token partitions. For this reason, by default the encoder
will do 8 token partitions.
- vpxenc supports partition output (-P) just in combination with
IVF output format (--ivf)
Performance:
- Realtime encoder can be up to 13% faster (ARM) depending on the number
of threads and bitrate settings. Constant gain over the 5-16 speed
range.
- Token buffer reduced from one frame to 8 MBs
Quality:
- quality is affected by the delayed context updates. This again
dependents on input material, speed and bitrate settings. For VC
style input the loss seen is up to 0.2dB. If error-resilient=2
mode is used than the effect of this change is negligible.
Example:
./configure --enable-realtime-only --enable-onthefly-bitpacking
./vpxenc --rt --end-usage=1 --fps=30000/1000 -w 640 -h 480
--target-bitrate=1000 --token-parts=3 --static-thresh=2000
--ivf -P -t 4 -o strm.ivf tanya_640x480.yuv
Change-Id: I127295cb85b835fc287e1c0201a67e378d025d76
Add the ability to specify multiple output streams on the command line.
Streams are delimited by --, and most parameters inherit from previous
streams.
In this implementation, resizing streams is still not supported. It
does not make use of the new multistream support in the encoder either.
Two pass support runs all streams independently, though it's
theoretically possible that we could combine firstpass runs in the
future. The logic required for this is too tricky to do as part of this
initial implementation. This is mostly an effort to get the parameter
passing and independent streams working from the application's
perspective, and a later commit will add the rescaling and
multiresolution support.
Change-Id: Ibf18c2355f54189fc91952c734c899e5c072b3e0
dynamicly assign ARG_CTRL_CNT_MAX and
add check to make sure argument instance
doesnt already exist before creating a duplicate
Change-Id: I4f78a9c5346cda8e812cd89c077afe8996493508
To avoid a dependency on vpx_version.h, call the vpx_codec_version_str()
function and build up the string manually.
Change-Id: Ie650e9b8f2aaaffaa31da5e9ef3b566b972321b4
Since this is the only ABI incompatible change since the last release,
convert it to use the control interface instead. The member of the
configuration struct is replaced with the VP8E_SET_MAX_INTRA_BITRATE_PCT
control.
More significant API changes were expected to be forthcoming when this
control was first introduced, and while they continue to be expected,
it's not worth breaking compatibility for only this change.
Change-Id: I799d8dbe24c8bc9c241e0b7743b2b64f81327d59
Using small values for --buf-sz= in command line causes
floating point exception due to division by zero.
Change-Id: Ibfe2d44db922993a78ebc9a4a1087d9625de48ae
As reported in issue 331, vpxenc encoded incorrect webm file header
on big endian machines. This change fixed that.
Change-Id: I31924ebd476a87f3e88b9b5424540bf781d2b86f
For clips that are near 60fps and have a lot of alt refs, it's possible
that the ring buffer holding the previous frames sizes/pts could wrap
around, leading to a division by zero.
In addition to checking for this condition in the ring buffer loop,
the buffer size is made dependent on the actual frame rate in use,
rather than defaulting to 60, which should improve accuracy at frame
rates >= ~60.
Change-Id: If5a04d6e847316dc5f7504f25c01164cf9332be8
Add the --rate-hist=n option, which displays a histogram with n
buckets for the rate over the --buf-sz window.
Change-Id: I2807b5a1525c7972e9ba40839b37e92b23ceffaf
Add the --q-hist=n option, which displays a histogram with n buckets for
the quantizer selected on each frame.
Change-Id: I59b020c26b0acae0b938685081d9932bd98df5c9
Create a new input parameter to allow specifying
the packed frame stereo 3d format. A default value
of mono will be written in the absence of user
specified input
Change-Id: I576d9952ab5d7e2076fbf1b282016a9a1baaa103
Identified as a possible cause of issue #308, the code was silently
ignoring realloc failures, which would lead to corruption, memory
leaks, and likely a crash. The best we can do in this case is die
gracefully.
Change-Id: Ie5f6a853d367015be5b9712bd742778f3baeefd9
Map an enum to the --end-usage values, so you can specify
--end-usage=cq instead of --end-usage=2. The numerical values still
work for historical scripts, etc, but this is more user friendly.
Change-Id: I445ecd9638f801f5924a71eabf449bee293cdd34
Cast size_t to (unsigned long) and print it with the %lu format
string, which is more portable than C99's explict %zu for size_t.
This truncates on Windows x64 but otherwise works on 32 and 64 bit
platforms. In practice the stats file is unlikely to be so large.
Change-Id: I0432b3acf85fc6ba4ad50640942e1ca4614b21cb
Adds following targets to configure script to support RVCT compilation
without operating system support (for Profiler or bare metal images).
- armv5te-none-rvct
- armv6-none-rvct
- armv7-none-rvct
To strip OS specific parts from the code "os_support"-config was added
to script and CONFIG_OS_SUPPORT flag is used in the code to exclude OS
specific parts such as OS specific includes and function calls for
timers and threads etc. This was done to enable RVCT compilation for
profiling purposes or running the image on bare metal target with
Lauterbach.
Removed separate AREA directives for READONLY data in armv6 and neon
assembly files to fix the RVCT compilation. Otherwise
"ldr <reg>, =label" syntax would have been needed to prevent linker
errors. This syntax is not supported by older gnu assemblers.
Change-Id: I14f4c68529e8c27397502fbc3010a54e505ddb43
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
