How can I convert a video frame into a data image knowing that using getframe is unnecessary?

I'm using Matlab R2010a and I need to convert a video frame into an image for further treatment concerning the image but an error is always here:

 ??? Error using ==> frame2im
 Argument must be a valid movie matrix from GETFRAME

In my case I don't need getframe. So how can I do? A part of the code is the following:

 v= mmreader('news.avi');
 framedata= read(v,1);
 I1=frame2im(framedata);
 I1=imresize(I1,[128 128]);

Please can someone help me thanks

[Geoff Hayes]

Sam - what can you tell us about framedata? What is the data type and the dimensions?

[sam]

frame data is the first frame of the video 'news avi'. The goal is to convert this first frame into an image using the function frame 2im for further exploitation in my code

[sam]

Hi! even this code with getframe doesn't work

v= mmreader('news.avi');
framedata= read(v,1);
f = getframe ;             
[I1,map] = frame2im(f);

[Geoff Hayes]

Sam - please clarify the data type and dimensions of framedata. Also, why doesn't your above code work? If you are observing an error, then please copy and paste the full error message to your question.

[sam]

Framedata: type: a frame dimensions [512,512]

The error: ??? Error using ==> frame2im Argument must be a valid movie matrix from GETFRAME

Answer 1

[Walter Roberson]

 v = mmreader('news.avi');
 framedata = read(v,1);
 I1 = framedata;
 I1 = imresize(I1,[128 128]);

[sam]

thank you, It works!