Approaches to create a video in matlab

Question

What are the possibilities to create videos in Matlab? I was searching and found mainly 3 toolboxes that work in this field, image processing, image acquisition and control vision... but how can I do it without them, just to create the video from scratch? I'm interested in various approaches to have an overview, but I was unable to find any decent tutorial or consistent source of info on the internet.

Thanks for the help!

Answer 1

Here are some of the different ways to create movies in (core) MATLAB.

MOVIE2AVI

(deprecated, use VIDEOWRITER instead)

%# figure figure, set(gcf, 'Color','white') Z = peaks; surf(Z);  axis tight set(gca, 'nextplot','replacechildren', 'Visible','off');  %# preallocate nFrames = 20; mov(1:nFrames) = struct('cdata',[], 'colormap',[]);  %# create movie for k=1:nFrames    surf(sin(2*pi*k/20)*Z, Z)    mov(k) = getframe(gca); end close(gcf)  %# save as AVI file, and open it using system video player movie2avi(mov, 'myPeaks1.avi', 'compression','None', 'fps',10); winopen('myPeaks1.avi') 

AVIFILE

(deprecated, use VIDEOWRITER instead)

%# figure figure, set(gcf, 'Color','white') Z = peaks; surf(Z);  axis tight set(gca, 'nextplot','replacechildren', 'Visible','off');  %# create AVI object nFrames = 20; aviobj = avifile('myPeaks2.avi', 'fps',10);  %# create movie for k=1:nFrames    surf(sin(2*pi*k/20)*Z, Z)    aviobj = addframe(aviobj, getframe(gca)); end close(gcf)  %# save as AVI file, and open it using system video player aviobj = close(aviobj); winopen('myPeaks2.avi') 

VIDEOWRITER

%# figure figure, set(gcf, 'Color','white') Z = peaks; surf(Z);  axis tight set(gca, 'nextplot','replacechildren', 'Visible','off');  %# create AVI object nFrames = 20; vidObj = VideoWriter('myPeaks3.avi'); vidObj.Quality = 100; vidObj.FrameRate = 10; open(vidObj);  %# create movie for k=1:nFrames    surf(sin(2*pi*k/20)*Z, Z)    writeVideo(vidObj, getframe(gca)); end close(gcf)  %# save as AVI file, and open it using system video player close(vidObj); winopen('myPeaks3.avi') 

IMWRITE

(technically not a movie, but an animated GIF image)

%# figure figure, set(gcf, 'Color','white') Z = peaks; surf(Z);  axis tight set(gca, 'nextplot','replacechildren', 'Visible','off');  %# preallocate nFrames = 20; f = getframe(gca); [f,map] = rgb2ind(f.cdata, 256, 'nodither'); mov = repmat(f, [1 1 1 nFrames]);  %# create movie for k=1:nFrames     surf(sin(2*pi*k/20)*Z, Z)     f = getframe(gca);     mov(:,:,1,k) = rgb2ind(f.cdata, map, 'nodither'); end close(gcf)  %# create GIF and open imwrite(mov, map, 'myPeaks4.gif', 'DelayTime',0, 'LoopCount',inf) winopen('myPeaks4.gif') 

Answer 2

There is http://www.mathworks.de/help/techdoc/ref/videowriterclass.html

My approach is to print the single frames/figures to png files using the print function giving them filenames like 1.png, 2.png, ... and then I use the free FFMPEG converter to make a video.

ffmpeg -r 20 -i %d.png foo.avi

This allows for a lot of finetuning, when it comes to the parameters of the conversion (bitrate, codec, geometry etc.).