 --enable-cross-compile  --target-os=mingw32  --arch=x86_64 --disable-ffmpeg  --disable-ffplay  --disable-ffprobe  --disable-ffserver --disable-shared --enable-static --enable-gpl --enable-mmx --enable-mmx2 --disable-vaapi  --disable-devices --disable-pthreads  --disable-altivec  --disable-sse --disable-neon
#
# This file provides configuration options for ffmpeg
# and is included while GIMP-GAP configure script runs the ffmpeg configuration on Mingw Windows environment.
# (or on crosscompilation with windows OS as target both for win32 and win64 target architecture)
#
# Notes:
#  there is another variant of this file for Linux and Unix-like Os named: configure_options_ffmpeg.txt
#
# Tests on Windows MinGW using the gcc-4.6 compiler showed that special ffmpeg configure options
# were required to produce working exutables of the ffmpeg based video encoders.
# The options that were successful in my tests are:
#
#  --disable-altivec  --disable-sse --disable-neon
# 
# Those option turn off memory aling related optimizations.
#
# I also tested alternative variants 
#  --enable-memalign-hack  as suggested by the ffmpeg configure script
# this resulted in successful build, but in very unstable exutables
# that crashed very often on XP (and immediate on Windows7) tests.
#
# other configure options (as recommanded in older tutorials)
# --extra-cflags="--mno-cygwin --mms-bitfields" 
# --extra-ldflags="-W1,--add-stdcall-alias"
# were no longer supported by my newer gcc-4.6 compiler 
#
# --disable-devices        
#  configures ffmpeg without video devices that would require latests win32 api version to build on MinGW Win32 Systems.
#  disabling devices is not critical since GIMP-GAP does not use ffmpeg features that
#  require other access than plain videofile io.
# 
# recent ffmpeg releases does no longer support --enable-liba52
# for audio /mp3 encoding ffmpeg recommands to link with the external libraries.
#
# the gap main configure script checks if some of the external libs for ffmpeg
# are installed and adds further options automatically
#
#  --enable-libfaac 
#  --enable-libfaad  (versions after ffmpeg-0.6 have removed this option)
#  --enable-libmp3lame
#  --enable-libx264  (old name: --enable-x264)
#  --enable-libxvid  (old name: --enable-xvid)
#  --enable-swscale
#  --enable-nonfree
# options for the ffmpeg configure
#
# cross compilation for windows 64 bit target (on openSUSE 13.1 64 bit build machine)
#  --enable-cross-compile  --target-os=mingw32  --arch=x86_64

