Fast warp delta search for four and six param models in warp newmv

[jadhuran]

Decouple warp parameter searches

Add cost based early termination

Enabled for speed levels four and above

Results

Anchor: a341351

Speed 4

+-------+-------+------+------+------+------+-------+
| Class |  Y%   |  U%  |  V%  | YUV% | ENC% | DEC%  |
+-------+-------+------+------+------+------+-------+
| A1    |  0.07 | 0.32 | 0.28 | 0.09 | 97.6 | 100.7 |
| A2    | -0.01 | 0.23 | 0.20 | 0.00 | 95.3 | 100.1 |
+-------+-------+------+------+------+------+-------+

[yeqing-wu]

Thanks. It is a good tradeoff. I have some comments, please help take a look

[jadhuran]

Thanks. It is a good tradeoff. I have some comments, please help take a look

I have addressed your comments