Reason for revert:
Internal bots failed.
Original issue's description:
> Reland "Move smoothing filter to common audio".
>
> The original CL was this https://codereview.webrtc.org/2484153002/
>
> Due to failure with internal trial servers, it was reverted. This CL tries to reland it.
>
> BUG=webrtc:6443
>
> Committed: https://crrev.com/223641f1b903e41e77d88f03199b4cdb65255ec8
> Cr-Commit-Position: refs/heads/master@{#15227}
TBR=tommi@webrtc.org,solenberg@webrtc.org,terelius@webrtc.org,kjellander@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:6443
Review-Url: https://codereview.webrtc.org/2529943002
Cr-Commit-Position: refs/heads/master@{#15228}
Set the |qp_| field in EncodedImage before calling OnEncodedImage.
BUG=webrtc:6541
Review-Url: https://codereview.webrtc.org/2499003002
Cr-Commit-Position: refs/heads/master@{#15199}
A recent cl (https://codereview.webrtc.org/2510583002) introduced an
issue where the initial rate allocation (call to VideoBitrateAllocator
and any associated temporal layers) uses framerate = 0 fps. This may
cause issues, including having the rate control in ScreenshareLayers
ramp up too slowly.
This CL make the initial call use VideoCodec.maxFramerate as framerate.
Also expanded unit tests.
BUG=webrtc:6301
Review-Url: https://codereview.webrtc.org/2513383002
Cr-Commit-Position: refs/heads/master@{#15166}
This is yet another reland of https://codereview.webrtc.org/2434073003/
including two fixes:
1. SimulcastRateAllocator did not handle the screenshare settings properly for numSimulcastStreams = 1. Additional test case was added for that.
2. In VideoSender, when rate allocation is updated after setting a new VideoCodec config, only update the state of the EncoderParameters, but don't actually run SetRateAllocation on the encoder itself. This caused some problems upstreams.
Please review only the changes after patch set 1.
Original description:
Extract bitrate allocation of spatial/temporal layers out of codec impl.
This CL makes a number of intervowen changes:
* Add BitrateAllocation struct, that contains a codec independent view
of how the target bitrate is distributed over spatial and temporal
layers.
* Adds the BitrateAllocator interface, which takes a bitrate and frame
rate and produces a BitrateAllocation.
* A default (non layered) implementation is added, and
SimulcastRateAllocator is extended to fully handle VP8 allocation.
This includes capturing TemporalLayer instances created by the
encoder.
* ViEEncoder now owns both the bitrate allocator and the temporal layer
factories for VP8. This allows allocation to happen fully outside of
the encoder implementation.
This refactoring will make it possible for ViEEncoder to signal the
full picture of target bitrates to the RTCP module.
BUG=webrtc:6301
R=stefan@webrtc.org
Review URL: https://codereview.webrtc.org/2510583002 .
Cr-Commit-Position: refs/heads/master@{#15105}
Reason for revert:
Broke a lot of tests in chromium.webrtc browser_tests. See e.g. https://build.chromium.org/p/chromium.webrtc/builders/Mac%20Tester/builds/62228 and https://build.chromium.org/p/chromium.webrtc/builders/Win8%20Tester/builds/30102.
[ RUN ] WebRtcVideoQualityBrowserTests/WebRtcVideoQualityBrowserTest.MANUAL_TestVideoQualityH264/1
...
#
# Fatal error in e:\b\c\b\win_builder\src\third_party\webrtc\modules\rtp_rtcp\source\rtp_format_h264.cc, line 170
# last system error: 0
# Check failed: packetization_mode_ == kH264PacketizationMode1 (0 vs. 2)
#
Original issue's description:
> Implement H.264 packetization mode 0.
>
> This approach extends the H.264 specific information with
> a packetization mode enum.
>
> Status: Parameter is in code. No way to set it yet.
>
> Rebase of CL 2009213002
>
> BUG=600254
>
> Committed: https://crrev.com/3bba101f36483b8030a693dfbc93af736d1dba68
> Cr-Commit-Position: refs/heads/master@{#15032}
TBR=hbos@webrtc.org,sprang@webrtc.org,mflodman@webrtc.org,hta@webrtc.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=600254
NOPRESUBMIT=true
Review-Url: https://codereview.webrtc.org/2500743002
Cr-Commit-Position: refs/heads/master@{#15050}
This approach extends the H.264 specific information with
a packetization mode enum.
Status: Parameter is in code. No way to set it yet.
Rebase of CL 2009213002
BUG=600254
Review-Url: https://codereview.webrtc.org/2337453002
Cr-Commit-Position: refs/heads/master@{#15032}
Chrome coding standard now discourages use of references to smart
pointers. This cl updates some recent methods to the new conventions.
BUG=webrtc:6672
Review-Url: https://codereview.webrtc.org/2477233004
Cr-Commit-Position: refs/heads/master@{#15028}
Reason for revert:
Seems to be causing flakiness in perf test:
FullStackTest.ScreenshareSlidesVP8_2TL_LossyNet
Original issue's description:
> Reland of Issue 2434073003: Extract bitrate allocation ...
>
> This is a reland of https://codereview.webrtc.org/2434073003/ including
> some fixes for failing test cases.
>
> Original description:
>
> Extract bitrate allocation of spatial/temporal layers out of codec impl.
>
> This CL makes a number of intervowen changes:
>
> * Add BitrateAllocation struct, that contains a codec independent view
> of how the target bitrate is distributed over spatial and temporal
> layers.
>
> * Adds the BitrateAllocator interface, which takes a bitrate and frame
> rate and produces a BitrateAllocation.
>
> * A default (non layered) implementation is added, and
> SimulcastRateAllocator is extended to fully handle VP8 allocation.
> This includes capturing TemporalLayer instances created by the
> encoder.
>
> * ViEEncoder now owns both the bitrate allocator and the temporal layer
> factories for VP8. This allows allocation to happen fully outside of
> the encoder implementation.
>
> This refactoring will make it possible for ViEEncoder to signal the
> full picture of target bitrates to the RTCP module.
>
> BUG=webrtc:6301
>
> Committed: https://crrev.com/647bf43dcb2fd16fccf276bd94dc4400728bb405
> Cr-Commit-Position: refs/heads/master@{#15023}
TBR=mflodman@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:6301
Review-Url: https://codereview.webrtc.org/2491393002
Cr-Commit-Position: refs/heads/master@{#15026}
This is a reland of https://codereview.webrtc.org/2434073003/ including
some fixes for failing test cases.
Original description:
Extract bitrate allocation of spatial/temporal layers out of codec impl.
This CL makes a number of intervowen changes:
* Add BitrateAllocation struct, that contains a codec independent view
of how the target bitrate is distributed over spatial and temporal
layers.
* Adds the BitrateAllocator interface, which takes a bitrate and frame
rate and produces a BitrateAllocation.
* A default (non layered) implementation is added, and
SimulcastRateAllocator is extended to fully handle VP8 allocation.
This includes capturing TemporalLayer instances created by the
encoder.
* ViEEncoder now owns both the bitrate allocator and the temporal layer
factories for VP8. This allows allocation to happen fully outside of
the encoder implementation.
This refactoring will make it possible for ViEEncoder to signal the
full picture of target bitrates to the RTCP module.
BUG=webrtc:6301
Review-Url: https://codereview.webrtc.org/2488833004
Cr-Commit-Position: refs/heads/master@{#15023}
Reason for revert:
Breaks perf tests.
Original issue's description:
> Extract bitrate allocation of spatial/temporal layers out of codec impl.
>
> This CL makes a number of intervowen changes:
>
> * Add BitrateAllocation struct, that contains a codec independent view
> of how the target bitrate is distributed over spatial and temporal
> layers.
>
> * Adds the BitrateAllocator interface, which takes a bitrate and frame
> rate and produces a BitrateAllocation.
>
> * A default (non layered) implementation is added, and
> SimulcastRateAllocator is extended to fully handle VP8 allocation.
> This includes capturing TemporalLayer instances created by the
> encoder.
>
> * ViEEncoder now owns both the bitrate allocator and the temporal layer
> factories for VP8. This allows allocation to happen fully outside of
> the encoder implementation.
>
> This refactoring will make it possible for ViEEncoder to signal the
> full picture of target bitrates to the RTCP module.
>
> BUG=webrtc:6301
>
> Committed: https://crrev.com/8f46c679d24a05b3f08e02c6d91ec9637f34e24f
> Cr-Commit-Position: refs/heads/master@{#14998}
TBR=stefan@webrtc.org,perkj@webrtc.org,mflodman@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:6301
Review-Url: https://codereview.webrtc.org/2489843002
Cr-Commit-Position: refs/heads/master@{#15001}
This CL makes a number of intervowen changes:
* Add BitrateAllocation struct, that contains a codec independent view
of how the target bitrate is distributed over spatial and temporal
layers.
* Adds the BitrateAllocator interface, which takes a bitrate and frame
rate and produces a BitrateAllocation.
* A default (non layered) implementation is added, and
SimulcastRateAllocator is extended to fully handle VP8 allocation.
This includes capturing TemporalLayer instances created by the
encoder.
* ViEEncoder now owns both the bitrate allocator and the temporal layer
factories for VP8. This allows allocation to happen fully outside of
the encoder implementation.
This refactoring will make it possible for ViEEncoder to signal the
full picture of target bitrates to the RTCP module.
BUG=webrtc:6301
Review-Url: https://codereview.webrtc.org/2434073003
Cr-Commit-Position: refs/heads/master@{#14998}
Reason for revert:
Fix gyp build
Original issue's description:
> Revert of Add a webrtc{en,de}coderfactory implementation for VideoToolbox (patchset #2 id:20001 of https://codereview.webrtc.org/2463313002/ )
>
> Reason for revert:
> Broke dependent project because the .gn changes weren't accompanied by corresponding .gyp changes.
>
> Original issue's description:
> > Add a webrtc{en,de}coderfactory implementation for VideoToolbox
> >
> > This CL removes the coupling of the VideoToolbox h264 implementation
> > to the generic h264 code. The files have been moved into sdb/obj/Framework
> > and all dependency on them has been removed from the rest of WebRTC.
> > We now add it as an external encoder via a factory supplied to the
> > CreatePeerConnectionFactory call. This also brings the iOS implementation
> > closer to what we do on Android for MediaCodec.
> >
> > BUG=webrtc:6619
> >
> > Committed: https://crrev.com/6a5047dad31f14f53dd9f8bc1ecde19e1dede2e4
> > Cr-Commit-Position: refs/heads/master@{#14953}
>
> TBR=magjed@webrtc.org,stefan@webrtc.org,kthelgason@webrtc.org
> BUG=webrtc:6619
>
> Committed: https://crrev.com/d69ad84420d9c0e1c11450c352f6c92e7c9583f1
> Cr-Commit-Position: refs/heads/master@{#14985}
R=magjed@webrtc.orgTBR=kwiberg@webrtc.org, magjed@webrtc.org, stefan@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:6619
Review URL: https://codereview.webrtc.org/2487723004 .
Cr-Commit-Position: refs/heads/master@{#14992}
Reason for revert:
Broke dependent project because the .gn changes weren't accompanied by corresponding .gyp changes.
Original issue's description:
> Add a webrtc{en,de}coderfactory implementation for VideoToolbox
>
> This CL removes the coupling of the VideoToolbox h264 implementation
> to the generic h264 code. The files have been moved into sdb/obj/Framework
> and all dependency on them has been removed from the rest of WebRTC.
> We now add it as an external encoder via a factory supplied to the
> CreatePeerConnectionFactory call. This also brings the iOS implementation
> closer to what we do on Android for MediaCodec.
>
> BUG=webrtc:6619
>
> Committed: https://crrev.com/6a5047dad31f14f53dd9f8bc1ecde19e1dede2e4
> Cr-Commit-Position: refs/heads/master@{#14953}
TBR=magjed@webrtc.org,stefan@webrtc.org,kthelgason@webrtc.org
BUG=webrtc:6619
Review-Url: https://codereview.webrtc.org/2483273002
Cr-Commit-Position: refs/heads/master@{#14985}
I have no idea how bad it is that we're hitting this limit; I'm just
doing this to stop the tests from flaking.
BUG=webrtc:6484
Review-Url: https://codereview.webrtc.org/2477663002
Cr-Commit-Position: refs/heads/master@{#14974}
This CL removes the coupling of the VideoToolbox h264 implementation
to the generic h264 code. The files have been moved into sdb/obj/Framework
and all dependency on them has been removed from the rest of WebRTC.
We now add it as an external encoder via a factory supplied to the
CreatePeerConnectionFactory call. This also brings the iOS implementation
closer to what we do on Android for MediaCodec.
BUG=webrtc:6619
Review-Url: https://codereview.webrtc.org/2463313002
Cr-Commit-Position: refs/heads/master@{#14953}
This change the interface of the PacketBuffer since the bitstream data of the packet has to be persistent when inserted into the PacketBuffer.
BUG=webrtc:5514
R=stefan@webrtc.org
Review URL: https://codereview.webrtc.org/2476283002 .
Cr-Commit-Position: refs/heads/master@{#14949}
To differentiate between when a packet should be dropped or when a keyframe
is missing its SPS and/or SPS CopyAndFixBitstream now returns:
- kInsert, the packet should be inserted into the PacketBuffer.
- kDrop, the packet should be dropped.
- kRequestKeyframe, a keyframe should be requested.
BUG=webrtc:5514
Review-Url: https://codereview.webrtc.org/2477343002
Cr-Commit-Position: refs/heads/master@{#14948}
Since ffmpeg use an optimized bitstream reader that reads in chunks of 32/64
bits the bitstream buffer has to be increased in order for the reader to not
read out of bounds.
BUG=webrtc:5514
R=stefan@webrtc.org
Review URL: https://codereview.webrtc.org/2476513004 .
Cr-Commit-Position: refs/heads/master@{#14941}
Removed EncodedImageCallback::Encoded() and RtpRtcp::SendOutgoingData().
These methods should no longer be used anywhere and it's safe to remove
them.
BUG=chromium:621691
Committed: https://crrev.com/c681250aaa2025836db7669694e323898e5c2ca7
Review-Url: https://codereview.webrtc.org/2405173006
Cr-Original-Commit-Position: refs/heads/master@{#14923}
Cr-Commit-Position: refs/heads/master@{#14935}
Reason for revert:
Still breaks internal downstream project.
Sergey: Please update internal project before relanding this.
Original issue's description:
> Remove deprected functions from EncodedImageCallback and RtpRtcp
>
> Removed EncodedImageCallback::Encoded() and RtpRtcp::SendOutgoingData().
> These methods should no longer be used anywhere and it's safe to remove
> them.
>
> BUG=chromium:621691
>
> Committed: https://crrev.com/c681250aaa2025836db7669694e323898e5c2ca7
> Cr-Commit-Position: refs/heads/master@{#14923}
TBR=mflodman@webrtc.org,stefan@webrtc.org,sergeyu@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:621691
Review-Url: https://codereview.webrtc.org/2479643002
Cr-Commit-Position: refs/heads/master@{#14925}
Removed EncodedImageCallback::Encoded() and RtpRtcp::SendOutgoingData().
These methods should no longer be used anywhere and it's safe to remove
them.
BUG=chromium:621691
Review-Url: https://codereview.webrtc.org/2405173006
Cr-Commit-Position: refs/heads/master@{#14923}
Since it is unsafe to hand out a pointer to a packet that might be removed/
overwritten at any time we now return a copy of the header if it exist.
BUG=webrtc:5514
Review-Url: https://codereview.webrtc.org/2468183002
Cr-Commit-Position: refs/heads/master@{#14920}
Reason for revert:
Breaks everything
Original issue's description:
> Revert of Remove deprected functions from EncodedImageCallback and RtpRtcp (patchset #4 id:100001 of https://codereview.webrtc.org/2405173006/ )
>
> Reason for revert:
> This might be breaking projects downstream.
>
> Original issue's description:
> > Remove deprected functions from EncodedImageCallback and RtpRtcp
> >
> > Removed EncodedImageCallback::Encoded() and RtpRtcp::SendOutgoingData().
> > These methods should no longer be used anywhere and it's safe to remove
> > them.
> >
> > BUG=chromium:621691
> >
> > Committed: https://crrev.com/fa565842718ad178a7562721b25d916fbabc2b92
> > Cr-Commit-Position: refs/heads/master@{#14902}
>
> TBR=mflodman@webrtc.org,stefan@webrtc.org,sergeyu@chromium.org
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=chromium:621691
>
> Committed: https://crrev.com/6c78307a21252c2dbd704f6d5e92a220fb722ed4
> Cr-Commit-Position: refs/heads/master@{#14914}
TBR=mflodman@webrtc.org,stefan@webrtc.org,sergeyu@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:621691
Review-Url: https://codereview.webrtc.org/2467373003
Cr-Commit-Position: refs/heads/master@{#14915}
Reason for revert:
This might be breaking projects downstream.
Original issue's description:
> Remove deprected functions from EncodedImageCallback and RtpRtcp
>
> Removed EncodedImageCallback::Encoded() and RtpRtcp::SendOutgoingData().
> These methods should no longer be used anywhere and it's safe to remove
> them.
>
> BUG=chromium:621691
>
> Committed: https://crrev.com/fa565842718ad178a7562721b25d916fbabc2b92
> Cr-Commit-Position: refs/heads/master@{#14902}
TBR=mflodman@webrtc.org,stefan@webrtc.org,sergeyu@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:621691
Review-Url: https://codereview.webrtc.org/2474433008
Cr-Commit-Position: refs/heads/master@{#14914}
The H264SpsPpsTracker class:
- Keeps track of all received SPS/PPS.
- Decides whether a packet should be inserted into the PacketBuffer or not.
- Don't insert if this packet only contains SPS and/or PPS.
- Don't insert if this is the first packet of and IDR and we have not
received the required SPS/PPS.
- Insert start codes, and in the case of the first packet of an IDR prepend
the bitstream with the given SPS/PPS for this IDR.
BUG=webrtc:5514
Review-Url: https://codereview.webrtc.org/2466993003
Cr-Commit-Position: refs/heads/master@{#14906}
Removed EncodedImageCallback::Encoded() and RtpRtcp::SendOutgoingData().
These methods should no longer be used anywhere and it's safe to remove
them.
BUG=chromium:621691
Review-Url: https://codereview.webrtc.org/2405173006
Cr-Commit-Position: refs/heads/master@{#14902}
This CL replaces the use of webrtc::Video as an internal
variable in the H.264 encoder with the specific fields
that are used by this encoder.
In support of refactorings discussed around:
BUG=600254
Committed: https://crrev.com/2549437b5ccf5aae2e6f1a1491c5f505d1859f9c
Review-Url: https://codereview.webrtc.org/2468903003
Cr-Original-Commit-Position: refs/heads/master@{#14887}
Cr-Commit-Position: refs/heads/master@{#14892}
Reason for revert:
Landed the wrong patchset. Nothing broken.
Original issue's description:
> Remove webrtc::Video from H264 encoder internals
>
> This CL replaces the use of webrtc::Video as an internal
> variable in the H.264 encoder with the specific fields
> that are used by this encoder.
>
> In support of refactorings discussed around:
>
> BUG=600254
>
> Committed: https://crrev.com/2549437b5ccf5aae2e6f1a1491c5f505d1859f9c
> Cr-Commit-Position: refs/heads/master@{#14887}
TBR=magjed@webrtc.org,stefan@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=600254
Review-Url: https://codereview.webrtc.org/2472673002
Cr-Commit-Position: refs/heads/master@{#14888}
This CL replaces the use of webrtc::Video as an internal
variable in the H.264 encoder with the specific fields
that are used by this encoder.
In support of refactorings discussed around:
BUG=600254
Review-Url: https://codereview.webrtc.org/2468903003
Cr-Commit-Position: refs/heads/master@{#14887}
In this CL:
- Don't insert a packet if we have explicitly cleared past it.
- Added some logging to ExpandBufferSize.
- Renamed IsContinuous to PotentialNewFrame.
- Unittests updated/added for this new behavior.
- Refactored TestPacketBuffer unittests.
BUG=webrtc:5514
R=danilchap@webrtc.org, stefan@webrtc.org
Review URL: https://codereview.webrtc.org/2399373002 .
Cr-Commit-Position: refs/heads/master@{#14871}
The new code is only exercised in tests so far. The H264 profile-level-id
parsing is not complete, but it should be enough for our purposes for
now.
BUG=webrtc:6400,webrtc:6337
Review-Url: https://codereview.webrtc.org/2459633002
Cr-Commit-Position: refs/heads/master@{#14850}
Replaced with a size() method, returning the corresponding attribute
(_length) of the underlying EncodedImage.
BUG=None
Review-Url: https://codereview.webrtc.org/2444193010
Cr-Commit-Position: refs/heads/master@{#14809}
Reason for revert:
Internal project has been fixed
Original issue's description:
> Revert of Move bitstream parser to more appropriate directory. (patchset #4 id:60001 of https://codereview.webrtc.org/2370853005/ )
>
> Reason for revert:
> Breaks internal project
>
> Original issue's description:
> > Move current bitstream parser to more appropriate directory.
> >
> > This CL groups together the code that has to do with parsing H264 bitstreams.
> > This code logically belongs together, and having it in the same directory not
> > only simplifies things from a project structure perspective, but also makes it
> > easier to refactor out common parts incrementally.
> > An added benefit is that this simplifies modular compilation, where for example
> > one would like a build of WebRTC without the H264 codec-specific parts.
> >
> > BUG=webrtc:6338
> >
> > Committed: https://crrev.com/cc6817e9ce4a5ffc73efb660cf0368afbc7d9a4f
> > Cr-Commit-Position: refs/heads/master@{#14684}
>
> TBR=magjed@webrtc.org,stefan@webrtc.org
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=webrtc:6338
>
> Committed: https://crrev.com/f04f14e772f803de39f8a6128e5157127cd35103
> Cr-Commit-Position: refs/heads/master@{#14685}
TBR=magjed@webrtc.org,stefan@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:6338
Review-Url: https://codereview.webrtc.org/2434043002
Cr-Commit-Position: refs/heads/master@{#14783}
This refactoring allows runtime checks that functions that access
codec specific information are using the correct union member.
The API also allows replacing the union with another implementation
without changes at calling sites.
BUG=webrtc:6603
Review-Url: https://codereview.webrtc.org/2001533003
Cr-Commit-Position: refs/heads/master@{#14775}
The API has changed for the slice config of SSpatialLayerConfig as of
OpenH264 v1.6. Update H264EncoderImpl with an ifdef that uses the
correct API depending on what version of OpenH264 is being used.
BUG=webrtc:6583
Review-Url: https://codereview.webrtc.org/2440113002
Cr-Commit-Position: refs/heads/master@{#14762}
This CL makes scaling and cropping lazy in AVFoundationVideoCapturer and
provides optimized paths for SW and HW encoding. For SW encoding, an
efficient NV12 -> I420 cropping and scaling is implemented in
CoreVideoFrameBuffer::NativeToI420. For HW encoding, an efficient NV12 ->
NV12 cropping and scaling is implemented in
CoreVideoFrameBuffer::CropAndScaleTo. The performance improvement over
the existing cropping and scaling is that it is now done in one step
instead of making an intermediary copy of the Y plane.
There might still be room for improvement in the HW path using some HW
support. That will be explored in a future CL.
BUG=b/30939444
Review-Url: https://codereview.webrtc.org/2394483005
Cr-Commit-Position: refs/heads/master@{#14701}
