how to read 12bit raw data faster

This is my way to read 12bit raw image file.

data = fread(p,[768,1024],'ubit12=>uint32',4,'l');

But it takes very long time, is there any other way to speed up the processing time?

Thanks!

[Walter Roberson]

Is the data really packed in groups of 12 consecutive bits? It is not impossible, but it would be somewhat unusual.

[Sounder]

one 12 bits pixel is stored in 2 bytes. It's combined with 4bits of random number and 12 bits of data. So this is the only ezsy way I know to implement, but it takes long time to read.

Answer 1

[Jan]

You can read all 16 bits and set the upper 4 bits to zero:

data = fread(p, [768,1024], 'uint16');
b    = uint32(rem(data, 4096));

I assume you can use the format 'uint16=>uint32' directly - please test if this is faster and if rem works on UINT32 arrays.

[Sounder]

lol it works! 23.5x speedup, thank you