IMAGE BINARIZE determine THRESHOLD

Hi,

i have one set data image grey scale. pixel value from 0 - 1300.

Then i want to threshold is 1300*0.4 = 520 . then the pixel number greater than 520 is 1, the pixel value smaller than 520 is 0.

Then this is my coding,

spect = dicomread ('astitr8sub32.dcm');
MAX = max(max(max(spect)));
T = MAX*0.4;
PVmin = T;
PVmax = MAX;
spect(spect<PVmin)=0;
spect(spect>PVmax)=0;
spect(spect~=0)=1;

spectmax=max(max(max(spect));
spectmin=min(min(min(spect)));
spectrange=spectmax-spectmin;

now i want convert my grey scale to binary image using function adaptthresh,

spect = dicomread ('astitr8sub32.dcm');
MAX = max(max(max(spect)));
T = adaptthresh(spect, 0.4);
BW = imbinarize(spect, T);

spect(spect==BW)=0;
spect(spect==BW)=1;

spectmax=max(max(max(spect)));
spectmin=min(min(min(spect)));
spectrange=spectmax-spectmin;

BUT i GOT ERROR.

CAN SOME ONE HELP ME?

[Matt J]

What error?

[KALYAN ACHARJYA]

I did not find any coding error, more this

max(max(max(spect)));

can be replace by

max(spect(:));

[mohd akmal masud]

tq all sir. it work