Bit rotation

Hi all,

i'm arduino begginer. How can i simple transfer this:
0000 0001 0000 0101 0110 0001 0110 1011 0010 1101‬
to this:
0000 1000 0000 1010 0110 1000 0110 1101 0100 1011‬

1 > 4
2 > 3
3 > 2
4 > 1

data are store in varibale: uint8_t buffer[BUFFER_SIZE];

Thank you for your help.

Chapter and verse

Or you can use bitRead() and bitWrite() to invert these "nibbles"