inigo \
--blank 49 \
-colour:red out=25 \
--blank 999 \
+-blank 49 colour:black out=25 -blank 999 \
-track \
clip3.dv in=200 out=275 \
-track \
start=-100%,0:100%x100%:100 \
end=0,0:100%x100%:100 \
-transition \
-mix:1 in=50 out=75 a_track=0 b_track=1 \
--transition \
-mix start=0 end=1 in=50 out=75 a_track=1 b_track=2 \
+mix:-1 in=50 out=75 a_track=1 b_track=2 \
$*