For 8-bit the subtrahend is small enough to fit into uint32_t.
This is the same that was done for:
c0241664a Resolve -Wshorten-64-to-32 in variance.
For 10/12-bit apply:
63a37d16f Prevent negative variance
Change-Id: Iab35e3f3f269035e17c711bd6cc01272c3137e1d
Due to rounding, hbd variance may become negative. This commit put in
check and clamp of negative values to 0.
Change-Id: I610d9c8aa2d4eebe7bc5f2c5624a9e3cadad4c94
This reverts commit ea48370a50, reversing
changes made to 15939cb2d7.
The commit was insufficiently tested and causes failures.
Change-Id: I623d6fc2cd3ae6fd42d0abab1f8eada465ae57a7
In 32-bit build with --enable-shared, there is a lot of
register pressure and register src_strideq is reused.
The code needs to use the stack based version of src_stride,
but this doesn't compile when used in an lea instruction.
This patch also fixes a related segmentation fault caused by the
implementation using src_strideq even though it has been
reused.
This patch also fixes the HBD subpel variance tests that fail
when compiled without disable-optimizations.
These failures were caused by local variables in the assembler
routines colliding with the caller's stack frame.
Change-Id: Ice9d4dafdcbdc6038ad5ee7c1c09a8f06deca362
Always round sum error and sum square error toward zero in variance
calculations. This prevents variance from becoming negative.
Avoiding rounding variance at all might be better but would be far
more invasive.
Change-Id: Icf24e0e75ff94952fc026ba6a4d26adf8d373f1c