README updated with usage and file structure

.gitignore

@@ -1,2 +1,3 @@
 frames
-small1.avi
+small1.avi
+em_small.avi

README.md

@@ -1,4 +1,4 @@
-## Data Communications (CO250): Mini-Project
+# Data Communications (CO250): Mini-Project
 
 **Title:**
 
@@ -46,10 +46,47 @@ Ramadhan J. Mstafa, Khaled M. Elleithy, "A highly secure video steganography usi
 [View Paper](http://ieeexplore.ieee.org/document/6845191/)
 
 
+## Usage
+
+Run the following files in order 
+1. `main.m` : In the `frames` directory the following would be present
+    * `framesRGB` : RGB frames of the video small.mp4
+    * `framesY` : srambled Y components for RGB frames
+    * `framesU` : srambled U components for RGB frames
+    * `framesV` : srambled V components for RGB frames
+
+2. `embed_message.m` : The binary image `message.png` will be embedded into the scrambled Y, U, V components. 
+
+3. `combine_frames.m` : In the directory `frames\embeddedFramesRGB`, the embedded RGB frames will be created.
+
+4. `frames_to_video.m` : Video named `em_small.avi` will be created from the embedded RGB frames.
+
+
 ## File Structure
 
-* Introduction.md - Explains theoretical aspects of the mini project.
+* `Introduction.md` - Explains theoretical aspects of the mini project.
+
+* `Design.md` - Explains design aspects of the mini project.
+
+* `main.m` - Main module of the implementation.
+
+* `construct_frames.m` - Construct RGB frames from the video and get their Y, U, V components. Save them in the mentioned      location.
+
+* `embed_message.m` - Applying (7, 4) Hamming Code to the message and embed the same into the scrambled Y, U, V frames.
+
+* `combine_frames.m` - Combine the embedded Y, U, V frames into their embedded RGB frame.
+
+* `frames_to_video.m` - Construct the video from the embedded RGB frames.
+
+* `scramble.m` - Scrambles all the Y, U, V frames given their directory based on a key.
+
+* `unscramble.m` - Unscrambles all the Y, U, V frames given their directory based on a key.
+
+* `yuv2rgb.m` - Converts Y, U, V components into a single RGB frame.
+
+* `rgb2yuv.m` - Converts a RGB frame to its Y, U, V components.
+
+* `small.mp4` - Video used to embed message into.
 
-* Design.md - Explains design aspects of the mini project.
+* `message.png` - Binary image to be sent after embedding it into small.mp4 video and retreived at the other end.
 
-* main.m - Main module of the implementation.

construct_frames.m

@@ -1,23 +1,22 @@
 % Construct frames from video and store in respective directories
 function construct_frames(video, workingDir, frameLocationRGB, frameLocationY, frameLocationU, frameLocationV) 
+
     i = 1;
     %=== Convert each video frame into different formats and store them ===%
     while hasFrame(video)
-       % Read frame from the video %
+       % read frame from the video %
        img = readFrame(video);
-       % Get YCbCr format from inbuilt function %
-       % YCbCr = rgb2ycbcr(img);
-       % Get YUV format from function defined in rgb2yuv.m %
+
+       % get YUV format from function defined in rgb2yuv.m %
        % each frame's Y, U, V component to be stored separately %
        [Y, U, V] = rgb2yuv(img);
-       % Naming for each frame %
+
+       % maming for each frame %
        filename = [sprintf('%d',i) '.bmp'];
 
        %=== Store the frames in their respective directories ===%
        fullname = fullfile(workingDir,frameLocationRGB,filename);
        imwrite(img,fullname);
-       % fullname = fullfile(workingDir,'imagesYCbCr',filename);
-       % imwrite(YCbCr,fullname);
        fullname = fullfile(workingDir,frameLocationY,filename);
        imwrite(Y,fullname);
        fullname = fullfile(workingDir,frameLocationU,filename);

frames_to_video.m

@@ -1,7 +1,7 @@
 %=== Set directory of frames ===%
 workingDir = 'frames';
 
-%=== get embedded RGB frames ===%
+%=== Get embedded RGB frames ===%
 imageNames = dir(fullfile(workingDir,'embeddedFramesRGB','*.bmp'));
 imageNames = {imageNames.name}';
 % for ii = 1:length(imageNames)
@@ -12,27 +12,27 @@
 video1 = VideoReader('small.mp4');
 
 %=== Set output video writer object ===%
-outputVideo = VideoWriter('small1.avi', 'Uncompressed AVI');
+outputVideo = VideoWriter('em_small.avi', 'Uncompressed AVI');
 % set lossless compression
 ouputVideo.LosslessCompression  = true;
-% Set same frame rate
+% Set same frame rate as original video
 outputVideo.FrameRate = video1.FrameRate
 open(outputVideo);
 
 %=== Frames to Video ===%
 for ii = 1:length(imageNames)
-   % Put frames in the video
+   % read a RGB frame
    img = imread(fullfile(workingDir,'embeddedFramesRGB',[sprintf('%d',ii) '.bmp']));
+   % put the frame in the video writer object
    writeVideo(outputVideo,img)
 end
 close(outputVideo);
 
 
+%=== Check if the frames after video formation ===% 
+%=== are same as the frames before =====%
 
-
-%=== Check if the frames after video formation % 
-% are same as the frames before =====%
-video = VideoReader('small1.avi');
+video = VideoReader('em_small.avi');
 i = 1;
 
 count = 0;

main.m

@@ -2,24 +2,23 @@
 workingDir = 'frames';
 mkdir(workingDir);
 mkdir(workingDir,'framesRGB');
-mkdir(workingDir,'framesYCbCr');
 mkdir(workingDir,'framesY');
 mkdir(workingDir,'framesU');
 mkdir(workingDir,'framesV');
 
 %=== Get video reader obj for the video ===%
 video = VideoReader('small.mp4');
 
-% construct frames from the video reader object
-% store them in these directories
+%=== construct frames from the video reader object ===%
+%=== store them in these directories ===%
 construct_frames(video, workingDir, 'framesRGB', 'framesY', 'framesU', 'framesV');
 
 %=== Get no of frames of the video ===%
 numOfFrames = floor(video.FrameRate*video.Duration) - 1;
 disp(numOfFrames);
 
-% Fix a key %
+%=== Fix a key ===%
 key = 5;
 
-% scamble the video frames
+%=== scamble the video frames ===%
 scramble(key, workingDir, 'framesY', 'framesU', 'framesV');

rgb2yuv.m

@@ -4,7 +4,7 @@
     R = RGB(:,:,1); 
     G = RGB(:,:,2); 
     B = RGB(:,:,3); 
-    % Conversion formula
+    % Conversion formula RGB to YUV
     Y = 0.299 * R + 0.587 * G + 0.114 * B; 
     U = (-0.14713 * R )- (0.28886 * G) + (0.436 * B); 
     V = 0.615 * R - 0.51499 * G - 0.10001 * B; 

yuv2rgb.m

@@ -1,6 +1,6 @@
 %yuv2rgb Convert Y, U, V components of a frame to a RGB frame
 function [RGB] = yuv2rgb( Y, U, V )
-    % Conversion formula
+    % Conversion formula YUV to RGB
     R = Y + 1.139834576 * V;
     G = Y -.3946460533 * U -.58060 * V;
     B = Y + 2.032111938 * U;