I need a MATLAB syntax for video modulation using QAM

This is my code :...but further iam unable to continue:

clc; clear all; close all; a=VideoReader('F:\whatsapp\video\VID-20141230-WA0001.mp4'); nFrames=a.NumberOfFrames; for k=1:nFrames img=read(a,k); %X=randn(300,400,3); z=img(:,:,1); %b=reshape(reflectances,1,300*400,3); %b=reshape(b,300*400,3); %p=imresize(img,[256 256]); %i=double(p); %i=im2bw(img); %=im2uint8(img); %y =modem.qammod('4',i,16); %y=qammod(z,16); %rgbSum=double(img); % for fr=2:nFrames % thisFrame=double(read(a,fr)); % rgbSum=rgbSum+thisFrame; % end % rgbMean=rgbSum/nFrames; figure(1),imshow(img,[]);

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