Python 3, 8888 84 bytes
l=2;s=''
for c in''.join(bin(128+ordf'{ord(c))[3:]for07b}'for c in input()):s+='01'[l!=c];l=c
print(s)
I feel that the assignments should be avoidable, but couldn't think of any way to do that.
Update:
- -4 bytes thanks to movatica