Can anyone help me to debug this error

V = 'army.avi';
xy1oObj = VideoReader (V); %Using video reader reading video
% Extracting frames
T = xyloObj.NumberOfframes % Calculate number of frames
for g = 1: T
    p = read(xyloObj, g); %retrieve data from video
    if (g ~=xyloObj.NumberOfFrames)
        J = read (xyloObj, g + 1);
        th = difference (p,J); %calculate histogram diff btwn two frames
        X(g) =th;
    end
end
% caculating mean and sd nd extracting frames
mean = mean2 (X)
std = std2 (X)
threshold = std + mean * 4
for g = 1: T
    p = read (xyloObj, g);
    if (g ~= xyloObj.NumberOfFrames)
        J = read (xyloObj, g + 1);
        th = difference (p,j);
        if (th> mean) %greater than threshold select key frame
            filename = fullfile ('C: \ Keyframes', sprintf ('frame_% frame20.JPG', g)); %writing keyframes
            imwrite (J, filename);
        end
    end
end
function[ r ] = difference (f1,f2)
k = rgb2gray (f1);%convert into grayscale
l = rgb2gray (f2);
f11 = imhist (k); %histogram of data
f12 = imhiist (l);
diffe = imabsdiff (f11, f12); %absolute different of two images
r = sum(diffe);
end

error is:

Error: File: differ.m Line: 28 Column: 1
Function definitions are not permitted in this context.

Undefined variable "xyloObj" or function "xyloObj.NumberOfframes".

Error in differ (line 4)
T = xyloObj.NumberOfframes % Calculate number of frames

[Stephen23]

@Sangeetha Srinivas: what MATLAB version are you using?

[Sangeetha Srinivas]

matlab 2014 version

Answer 1

[Guillaume]

The ability to define functions in scripts was introduced in R2016b. In earlier version, your function must be in its own file. Therefore you must move your difference function into its own difference.m file.

[Sangeetha Srinivas]

If I do that i'm getting another error as Undefined variable "xyloObj" or function "xyloObj.NumberOfframes".

Error in differ (line 4) T = xyloObj.NumberOfframes % Calculate number of frames

[Dennis]

Try

xyloObj = VideoReader (V);

[Guillaume]

xy1oObj = VideoReader (V)

The character between xy and oObj is the number 1.

T = xyloObj.NumberOfframe

The character between xy and oObj is the letter el.

You need to be consistent!

[Sangeetha Srinivas]

Thank you sir.But im still getting errors please help me out to solve it. Attempt to execute SCRIPT rgb2gray as a function: C:\Users\roshini\Documents\MATLAB\rgb2gray.m

Error in difference (line 2) k = rgb2gray (f1);%convert into grayscale

Error in differ (line 9) th = difference (p,J); %calculate histogram diff btwn two frames

[Sangeetha Srinivas]

I have extracted frames from a video now I need to find the absolute frame difference between two frames.Sir, can u please help me out.

[Guillaume]

I have no idea what an absolute frame difference is. In any case, this is a topic for a new question.

[Sangeetha Srinivas]

It is nothing but finding out difference between two images.

now can u please help me out to solve this problem Attempt to execute SCRIPT rgb2gray as a function: C:\Users\roshini\Documents\MATLAB\rgb2gray.m

Error in difference (line 2) k = rgb2gray (f1);%convert into grayscale

Error in differ (line 9) th = difference (p,J); %calculate histogram diff btwn two frames

[Guillaume]

It is nothing but finding out difference between two images.

Depending on what difference mean, that can be a huge topic.

With regards to the error, it looks like you named your script rgb2gray.m which of course prevent you from using the function rgb2gray. Don't name the script the same as functions you use.

Note that if that C:\Users\roshini\Documents\MATLAB\rgb2gray.m file is actually the difference function I told you to create, then its name must be C:\Users\roshini\Documents\MATLAB\difference.m and its content:

function [r] = difference (f1,f2)
   k = rgb2gray (f1);%convert into grayscale
   l = rgb2gray (f2);
   f11 = imhist (k); %histogram of data
   f12 = imhiist (l);
   diffe = imabsdiff (f11, f12); %absolute different of two images
   r = sum(diffe);
end