movie2gif.m

function movie2gif(mov, gifFile, varargin)
% ==================
% Matlab movie to GIF Converter.
%
% Syntax: movie2gif(mov, gifFile, prop, value, ...)
% =================================================
% The list of properties is the same like for the command 'imwrite' for the
% file format gif:
%
% 'BackgroundColor' - A scalar integer. This value specifies which index in
%                     the colormap should be treated as the transparent
%                     color for the image and is used for certain disposal
%                     methods in animated GIFs. If X is uint8 or logical,
%                     then indexing starts at 0. If X is double, then
%                     indexing starts at 1.
%
% 'Comment' - A string or cell array of strings containing a comment to be
%             added to the image. For a cell array of strings, a carriage
%             return is added after each row.
%
% 'DelayTime' - A scalar value between 0 and 655 inclusive, that specifies
%               the delay in seconds before displaying the next image.
%
% 'DisposalMethod' - One of the following strings, which sets the disposal
%                    method of an animated GIF: 'leaveInPlace',
%                    'restoreBG', 'restorePrevious', or 'doNotSpecify'.
%
% 'LoopCount' - A finite integer between 0 and 65535 or the value Inf (the
%               default) which specifies the number of times to repeat the
%               animation. By default, the animation loops continuously.
%               For a value of 0, the animation will be played once. For a
%               value of 1, the animation will be played twice, etc.
%
% 'TransparentColor' - A scalar integer. This value specifies which index
%                      in the colormap should be treated as the transparent
%                      color for the image. If X is uint8 or logical, then
%                      indexing starts at 0. If X is double, then indexing
%                      starts at 1
%
% *************************************************************************
% Copyright 2007-2013 by Nicolae Cindea.

if (nargin < 2)
    error('Too few input arguments');
end

if (nargin == 2)
    frameNb = size(mov, 2);
    isFirst = true;
    h = waitbar(0, 'Generate GIF file...');
    for i = 1:frameNb
        waitbar((i-1)/frameNb, h);
        [RGB, ~] = frame2im(mov(i));
        if (exist('rgb2ind', 'file'))
            [IND, map] = rgb2ind(RGB,256);
        else
            [IND, map] = aRGB2IND(RGB);
        end
        if isFirst
            imwrite(IND, map, gifFile, 'gif');
            isFirst=false;
        else
            imwrite(IND, map, gifFile, 'gif', 'WriteMode', 'append');
        end
    end
    close(h);
end

if (nargin > 2)
    h = waitbar(0, 'Generate GIF file...');
    frameNb = size(mov, 2);
    isFirst = true;
    for i = 1:frameNb
        waitbar((i-1)/frameNb, h);
        [RGB, ~] = frame2im(mov(i));
        if (exist('rgb2ind', 'file'))
            [IND, map] = rgb2ind(RGB,256);
        else
            [IND, map] = aRGB2IND(RGB);
        end
        if isFirst
            args = varargin;
            imwrite(IND, map, gifFile, 'gif', args{:});
            isFirst=false;
            
            % supress 'LoopCount' option from the args!!
            args = varargin;
            l = length(args);
            
            posLoopCount = 0;
            for ii = 1:l
                if(ischar(args{ii}))
                    if strcmp(args{ii}, 'LoopCount')
                        posLoopCount = ii;
                    end
                end
            end
            if (posLoopCount)
                args = {args{1:posLoopCount-1}, args{posLoopCount+2:end}};
            end
            
        else
            imwrite(IND, map, gifFile, 'gif', 'WriteMode', 'append', ...
                args{:});
        end
    end
    close(h);
end