Speeding bitand / bitshift and type conversion

We have a uint32 data word that is made of two uint16 variables, the first 16 bits is variable #1, the second 16 bits is variable #2. To convert, we are using bitand and type casting:

% Take 32-bit DataWord, convert into two 16-bit variables:
Var1 = uint16(bitshift(bitand(DataWord1,uint32(4294901760)),-16)); % 4294901760 = 0b11111111111111110000000000000000
Var2 = uint16(bitand(DataWord1,uint32(65535))); % 65535 = 0b00000000000000001111111111111111

We do this on an incoming data stream, and unfortunatley, our code above is too slow.

Originally we were using bitget, but it returns a row vector of bits, so getting that row vector into a single uint16 variable was even slower.

Thanks for any help to speed up the above.

Answer 1

[James Tursa]

Try this:

DataWord16 = typecast(DataWord1,'uint16'); % shared data copy for later versions of MATLAB
Var1 = DataWord16(1:2:end);
Var2 = DataWord16(2:2:end);

[Walter Roberson]

In some cases you would swapbytes() the result of typecast

[James Tursa]

Good point.

[C R]

For the data set I am working on this really sped things up. Thanks for the help!