Ffmpeg/x264 (profile High, level 3.0) (latest versions of x264)

gistfile1.sh

infile ="video.avi"
tmpfile="video_tmp.mp4"
outfile="video.mp4"
options="-vcodec libx264 -b 512k -flags +loop+mv4 -cmp 256 \
   -partitions +parti4x4+parti8x8+partp4x4+partp8x8+partb8x8 \
   -me_method hex -subq 7 -trellis 1 -refs 5 -bf 3 \
   -flags2 +bpyramid+wpred+mixed_refs+dct8x8 -coder 1 -me_range 16 \
         -g 250 -keyint_min 25 -sc_threshold 40 -i_qfactor 0.71 -qmin 10\
   -qmax 51 -qdiff 4"

ffmpeg -y -i "$infile" -an -pass 1 -threads 2 $options "$tmpfile"

ffmpeg -y -i "$infile" -acodec libfaac -ar 44100 -ab 96k -pass 2 -threads 2 $options "$tmpfile"

qt-faststart "$tmpfile" "$outfile"

From here