# Scalar OpenPOWER Audio and Video Opcodes

the fundamental principle of SV is a hardware for-loop. therefore the first (and in nearly 100% of cases only) place to put Vector operations is firat and foremost in the *scalar* ISA.

This page therefore has acompanying discussion at <https://bugs.libre-soc.org/show_bug.cgi?id=230> for evolution of suitable opcodes.

# Audio

TODO

# Video

TODO

## VSX SIMD

### vpkpx

vpkpx is a 32-bit to 16-bit 8888 into 1555 conversion

### vupkhpx / vupklpx

these are 16-bit to 32-bit 1555 to 8888 conversion

### vavgs*

signed and usigned, 8/16/32: these are all of the form:

    result = truncate((a + b + 1) >> 1))

### vabsdu*

unsigned 8/16/32: these are all of the form:

    result = (src1 > src2) ? truncate(src1-src2) :
                             truncate(src2-src1)

### vmaxs* / vmaxu* (and min)

signed and unsigned, 8/16/32: these are all of the form:

    result = (src1 > src2) ? src1 : src2 # max
    result = (src1 < src2) ? src1 : src2 # min