Refactor VideoDenoiser to use a buffer pool, replacing explicit double buffering.

Refactor VideoDenoiser to use a buffer pool, replacing explicit double buffering.

Also improve denoiser to not assume identical stride of all involved
frames, and delete the no longer needed function I420Buffer::CopyKeepStride.

BUG=None

Committed: https://crrev.com/18ee17d1e7876b95fa48a82360b20236624350b6
Cr-Commit-Position: refs/heads/master@{#14940}

[nisse-webrtc, 2016-11-01 14:19:02]

nisse@webrtc.org changed reviewers:
+ jackychen@webrtc.org, stefan@webrtc.org

[nisse-webrtc, 2016-11-01 14:19:03]

PTAL. I think we discussed this a few months ago (see cl
https://codereview.webrtc.org/2005733003/). But I realized that using a buffer
pool seems both cleaner and safer than just moving the double-buffering logic
inside the class.

Now each frame buffer is written to only in the same call which created it, and
all reuse is the responsibility of the buffer pool. In the common case, the
number of live buffers is unchanged.

Clearly, no change in behavior is intended, but I'm not sure how to verify that.
Are there any tests that check the behavior of the denoiser? The unit tests I've
found only check that we get identical result for C and assembly implementation
of the underlying filters.

[stefan-webrtc, 2016-11-02 13:11:01]

Description was changed from

==========
Refactor VideoDenoiser to use a buffer pool, replacing explicit double
buffering.

Also improve denoiser to not assume identical stride of all involved
frames, and delete the no longer needed function I420Buffer::CopyKeepStride.

On top of cl https://codereview.webrtc.org/2464073002/

BUG=None
==========

to

==========
Refactor VideoDenoiser to use a buffer pool, replacing explicit double
buffering.

Also improve denoiser to not assume identical stride of all involved
frames, and delete the no longer needed function I420Buffer::CopyKeepStride.

On top of cl https://codereview.webrtc.org/2464073002/

BUG=None
==========

[stefan-webrtc, 2016-11-02 13:11:01]

stefan@webrtc.org changed reviewers:
+ marpan@webrtc.org
- jackychen@webrtc.org

[stefan-webrtc, 2016-11-02 13:11:19]

Changing reviewer to marpan@ as jacky is no longer in the project.

[nisse-webrtc, 2016-11-02 14:19:30]

Description was changed from

==========
Refactor VideoDenoiser to use a buffer pool, replacing explicit double
buffering.

Also improve denoiser to not assume identical stride of all involved
frames, and delete the no longer needed function I420Buffer::CopyKeepStride.

On top of cl https://codereview.webrtc.org/2464073002/

BUG=None
==========

to

==========
Refactor VideoDenoiser to use a buffer pool, replacing explicit double
buffering.

Also improve denoiser to not assume identical stride of all involved
frames, and delete the no longer needed function I420Buffer::CopyKeepStride.

BUG=None
==========

[marpan, 2016-11-02 16:56:42]

marpan@google.com changed reviewers:
+ marpan@google.com

[marpan, 2016-11-02 16:56:42]

lgtm

[stefan-webrtc, 2016-11-03 13:37:27]

rs-lgtm

[nisse-webrtc, 2016-11-07 08:02:20]

The CQ bit was checked by nisse@webrtc.org

[commit-bot: I haz the power, 2016-11-07 08:02:31]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.webrtc.org/...

[commit-bot: I haz the power, 2016-11-07 09:35:01]

Description was changed from

==========
Refactor VideoDenoiser to use a buffer pool, replacing explicit double
buffering.

Also improve denoiser to not assume identical stride of all involved
frames, and delete the no longer needed function I420Buffer::CopyKeepStride.

BUG=None
==========

to

==========
Refactor VideoDenoiser to use a buffer pool, replacing explicit double
buffering.

Also improve denoiser to not assume identical stride of all involved
frames, and delete the no longer needed function I420Buffer::CopyKeepStride.

BUG=None
==========

[commit-bot: I haz the power, 2016-11-07 09:35:02]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-11-07 09:35:11]

Description was changed from

==========
Refactor VideoDenoiser to use a buffer pool, replacing explicit double
buffering.

Also improve denoiser to not assume identical stride of all involved
frames, and delete the no longer needed function I420Buffer::CopyKeepStride.

BUG=None
==========

to

==========
Refactor VideoDenoiser to use a buffer pool, replacing explicit double
buffering.

Also improve denoiser to not assume identical stride of all involved
frames, and delete the no longer needed function I420Buffer::CopyKeepStride.

BUG=None

Committed: https://crrev.com/18ee17d1e7876b95fa48a82360b20236624350b6
Cr-Commit-Position: refs/heads/master@{#14940}
==========

[commit-bot: I haz the power, 2016-11-07 09:35:11]

Patchset 2 (id:??) landed as
https://crrev.com/18ee17d1e7876b95fa48a82360b20236624350b6
Cr-Commit-Position: refs/heads/master@{#14940}