How do I convert my video (>2 GB) to uncompressed AVI grayscale in MATLAB 7.12 (R2011a)?

I need to convert my video that is greater than 2 GB to an uncompressed AVI. I want the video to be in grayscale. How can I go this in MATLAB?

Answer 1

[MathWorks Support Team]

In order to use the VideoWriter to create an uncompressed AVI in grayscale, you need to create a VideoWriter object with the profile set to 'Uncompressed AVI'. Then create a movie structure that has grayscale frames by using the RGB2GRAY function and use the WRITEVIDEO function to write the frames in the movie to the AVI file. Then close the VideoWriter object using the CLOSE function.

Please refer to the following sample code:

% Read sample video.

xyloObj = VideoReader('xylophone.mpg');

% Get details.

nFrames = xyloObj.NumberOfFrames;

vidHeight = xyloObj.Height;

vidWidth = xyloObj.Width;

% Define colormap

map = [(0:255)' (0:255)' (0:255)']/255;

% Preallocate movie structure.

mov(1:nFrames) = struct('cdata', zeros(vidHeight, vidWidth, 'uint8'),'colormap', map);

% Read one frame at a time.

for k = 1 : nFrames

      mov(k).cdata = rgb2gray(read(xyloObj, k));

end

% Prepare the new file.

vidObj = VideoWriter('videowrite.avi','Uncompressed AVI');

open(vidObj);

% Write video

writeVideo(vidObj, mov);

% Close video writer object

close(vidObj);