title: Undefined function or variable 'mmreader'
body: <p>I try to use matlab 2016a to read avi videos, however, I get the following problems:</p>
  
  <p>undefined funciton or variable 'mmreader';
  The code is as following:</p>
  
  <pre><code>clc;
  clear;
  %% this to read avi by using mmread to get every frame
  video = mmreader('D:\My Documents\MATLAB\My\fire.avi');
  nFrames = video.NumberOfFrames;
  H = video.Height;
  W = video.Width;
  Rate = video.FrameRate;
  % Preallocate movie structure.
  mov(1:nFrames) = struct('cdata',zeros(H,W,3,'uint8'),'colormap',[]);
  
  
  %read one frame every time
  for i = 1:nFrames
  mov(i).cdata = read(video,i);
  P = mov(i).cdata;
   disp('current frame number：'),disp(i);
   imshow(P),title('original picture');
  
  
  %     P2=rgb2gray(P);
  
  end
  </code></pre>
  
  <p>Why? Could anyone help me? Thanks in advance.</p>