The optimizer did something funny with the code around
line 1412.  Before the call to encode_sb split_dist was
set properly but after it was adjusted and converted to
a negative.

https://code.google.com/p/webm/issues/detail?id=714

Change-Id: I9a7631d5325ade2dc28c1030653a23eecec8721b

This commit enables the use of DC, vertical, and horizontal intra
prediction mode in rtc non-RD mode decision. When the best cost value
of inter modes is above a given threshold, the encoder runs the
above three intra modes and selects the one that has minimum
prediction residual in terms of SAD.

This together with recent changes on non-RD mode decision and coding
control improves compression performance of speed -6 by
derf  91%
yt    61%
hd    46%
stdhd 52%

In terms of encoding speed, it is about 3 times faster than speed -5.

Change-Id: I6b483bfd0307e6482bb22a6676ae4e25a52b1310

Change-Id: I70240e50927b4379603628f6349bf615f756b5a1

When non-RD coding decision is used in rtc mode, the alt reference
is not used for inter frame prediction. This commit disabled alt ref
option whenever speed -6 is used.

Change-Id: I0b33ca03661de1db2d9bef1bcbff848cd4c9396f

Change-Id: I39286df9fc76e3451f14ce2652d671e11b0c37bc

Cast result of round() to int.

Change-Id: Ib708fddfadde4c765001ce9723fda113fd0f4bf6

Cast result of round() to int.

Change-Id: I4982886ad4e7657b4c40d21bd850d31690a68c28

Current setting was specific to 1 layer case.
rc_target_bitrate is total bitrate for whole stream,
so set it to ts_target_bitrate for highest/top temporal layer.

Change-Id: I83de73364956fa21c0a7c971c9f390d4840457e6

Avoid special context setting for alt-ref in svc mode.

Change-Id: I5337d0739abe16aab7854bcaa3c8537191c4b60c

Change-Id: Ia9252ad0caa4d2bda529a3fe93efcb31e7eb2da0

Change-Id: I1210ce23cf8f98950c445a17ef51a73c6852c89f

Use unsigned loop counters in set_roi_map() and set_active_map().

Change-Id: I9bbaed38b51ef73b82ba4ad4c4bc18ca5d2399f9

Use unsigned int instead of uint64_t for duration and deadline
arguments to functions get_frame_stats() and encode_frame().

Change-Id: I1f26a7afc38ae89916b2c67415ced26fdc9d53e7

- Use size_t for frame_size() (fixes warnings elsewhere)
- Remove unnecessary use of const.

Change-Id: Id2cba182ac3fd2f67d25fd1db3a0bc3e1eda040b

This variable takes control parameters for vp9 encoder, hence
renamed vp9_cfg.

Change-Id: I9b253c41a06e44d97fe699f26005cd71e2eeb36c