Update VP8 settings to avoid spending bitrate on static areas. PERF NOTE

Update VP8 settings to avoid spending bitrate on static areas. PERF NOTE

This CL changes the threshold where we consider a block to be static and
of sufficient quality to not spend bits/CPU encoding it.

Perf note: This change may result in a minor degradation of PSNR/SSIM
and available send bitrate. CPU usage and bitrate sent should however
be greately reduced.

BUG=webrtc:5015
Committed: https://crrev.com/fb30c1b5d1effcc82a96fdf40814a03baf0727bf
Cr-Commit-Position: refs/heads/master@{#10134}

[sprang_webrtc, 2015-09-30 13:15:00]

sprang@webrtc.org changed reviewers:
+ marpan@webrtc.org, stefan@webrtc.org

[sprang_webrtc, 2015-09-30 13:15:00]

After manual visual tuning I set the STATIC_THRESHOLD to 300, seems to be
reasonable trade-off between low artifacts (esp after scrolling motion) and
quickly reaching a static mode. 

marpan@, you're the expert. :) WDYT?

[marpan, 2015-09-30 15:45:29]

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

[marpan, 2015-09-30 15:45:30]

one comment, and lgtm.

https://codereview.webrtc.org/1383533002/diff/1/webrtc/modules/video_coding/c...
File webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc (right):

https://codereview.webrtc.org/1383533002/diff/1/webrtc/modules/video_coding/c...
webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc:667:
vpx_codec_control(&(encoders_[i]), VP8E_SET_STATIC_THRESHOLD, 300);
condition this change only for screen_content_mode for now..

[stefan-webrtc, 2015-10-01 08:54:27]

lgtm

[sprang_webrtc, 2015-10-01 11:17:03]

https://codereview.webrtc.org/1383533002/diff/1/webrtc/modules/video_coding/c...
File webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc (right):

https://codereview.webrtc.org/1383533002/diff/1/webrtc/modules/video_coding/c...
webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc:667:
vpx_codec_control(&(encoders_[i]), VP8E_SET_STATIC_THRESHOLD, 300);
On 2015/09/30 15:45:30, marpan wrote:
> condition this change only for screen_content_mode for now..

Done.

[sprang_webrtc, 2015-10-01 11:17:06]

The CQ bit was checked by sprang@webrtc.org

[sprang_webrtc, 2015-10-01 11:17:07]

The patchset sent to the CQ was uploaded after l-g-t-m from marpan@google.com
Link to the patchset: https://codereview.webrtc.org/1383533002/#ps20001 (title:
"Addressed comment")

[commit-bot: I haz the power, 2015-10-01 11:17:14]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1383533002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1383533002/20001

[commit-bot: I haz the power, 2015-10-01 11:56:03]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-10-01 11:56:03]

Try jobs failed on following builders:
  win_drmemory_light on tryserver.webrtc (JOB_FAILED,
http://build.chromium.org/p/tryserver.webrtc/builders/win_drmemory_light/buil...)

[sprang_webrtc, 2015-10-01 13:24:55]

The CQ bit was checked by sprang@webrtc.org

[commit-bot: I haz the power, 2015-10-01 13:25:11]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1383533002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1383533002/20001

[commit-bot: I haz the power, 2015-10-01 13:26:16]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-10-01 13:26:24]

Patchset 2 (id:??) landed as
https://crrev.com/fb30c1b5d1effcc82a96fdf40814a03baf0727bf
Cr-Commit-Position: refs/heads/master@{#10134}