In the variance calculations the difference is summed and later squared.
When the sum exceeds sqrt(2^31) the value is treated as a negative when
it is shifted which gives incorrect results.
To fix this we force the multiplication to be unsigned.
The alternative fix is to shift sum down by 4 before multiplying.
However that will reduce precision.
For 16x16 blocks the maximum sum is 65280 and sqrt(2^31) is 46340 (and
change).
This change is based on:
1698234 Missed some variance casts
fea3556 Fix variance overflow
Change-Id: I2c61856cca9db54b9b81de83b4505ea81a050a0f
there are still a couple type of warning left, which are related to
double constants assigned to float type. As those would be addressed
by the conversion of transforms into integer version. This commit
has left those un-dealt with.
Change-Id: I48fd9b489c0c27ad6b543f4177423419f929f2bb
calculate the txfm_cache difference first as both values may be
INT64_MAX with the intent that they cancel each other out.
Change-Id: I214d072458e1b24f60289974e6302af1aff7b66c
rd_pick_intra4x4mby_modes / rd_pick_intra8x8mby_modes would both use the
input value of 'rate_y' in the return calculation. In many places this
value is uninitialized. Remove the unneeded sum.
Change-Id: Icbd3df685303000301e69291c0ebc06f74bd548d
