MJPEG Tools Svn

min = 2 * abs(*(frame+x+(y-1)*width) - *(frame+x+(y+1)*width)) is a lot
better (especially inside a double nested loop) than:
d = *(frame+x+(y-1)*width) - *(frame+x+(y+1)*width) ;
min = d < 0 ? -d:d;
d = *(frame+x+(y-1)*width) - *(frame+x+(y+1)*width) ;
min += d < 0 ? -d:d;
Also do a bit of tidying (unused/unneded ABS macro removed)

save a few cpu cycles, abs() is faster than (xxx < 0 ? -xxx : xxx)

Adjust the CFLAGS/AM_CFLAGS to use the new new PROGRAM_NOPIC option. Extra
flags (the old AM_CFLAGS) should be added by "--with-extra-cflags=..." at
./configure time (so that they apply to all programs and not just yuvdenoise)

Using abs() is _lots_ faster than a 'if < 0 ? ' construct since abs() is often a
compiler builtin (single machine instruction).

Implement building PROGRAMS (not SHARED LIBS) without PIC code - seems that
on a PPC (OS/X at least) the default is the (slightly) slower PIC mode. For
programs there is the "-mdynamic-no-pic" which should be used for non-shared
(but still dynamic) objects such as compute bound programs. On IA32 there
is the "-fno-PIC" which simply restates the default of non-pic code.

Thus far only a couple programs in lavtools/ have had their CFLAGS adjusted
to show how it's done. Over time other cpu intense programs will have the
same mods made.

Another update submitted by Nicolas Boos

Since we use a define, actually include the header that defines it

Updated with patch from Nicolas Boos

applied fix from Bug tracker:
[ 1041159 ] mplex -O: typo in mplex/main.cpp

-O is never satisfied with time offset units when none
given (according to man page, must default to ms.)

"mjpegtools-1.6.2/mplex/main.cpp" line 582 of 621: if(
e ) should obviously be if (*e).

Further speedup of the non-MMX/SSE SAD functions - shortcut the computation if
the current block has become worse than previously seen blocks.