function digital_rain_animation % Programmed in Matlab R2017a. % You can have a glimpse of the original digital rain in the  %   Matrix Movie at 1:04 (or youtube: /watch?v=3vAnuBtyEYE ). % The original is far messier. Drops stop, start and shift rows % additionally there are stuck letters, gaps and so on. % This is not replicated because it makes the short loop time very obvious. % Those features could be added in a longer video. % The font is not correct. % The code could be radically optimized, but hence it is intended for  %   one-time use, there is no real need.  latinList = ['-><=*' char(124) '":АБВГДЕЁЖЗИЙКЛМНОПРСТУФХЦЧШЩЪЫЬЭЮЯ0123456789']; % the vertical bar is encrypted as char(124) to avoid template-errors on wikimedia commons asianList = char(65393:65437); % Asian symbols; Half-width kana; % Matlab can work with UTF-8 but M-Files are saved using ANSI. If letters are typed directly, they are lost while saving the file charList = [latinList asianList asianList]; % aisan symbols twice as likely nChar = numel(charList);   [pathstr,fname] = fileparts(which(mfilename)); % save files under the same name and at file location   for gifVersion = [1 2 3 4 5 6]%          switch gifVersion         case 1             rng(1) % seed random generator to make results reproducible             name = 'small_letters';             nFrames = 250;             sizeLetters = [25 42]; % [nLetterRows nLetterColumns]             dropLength = 35; % should be adjusted with regard to nFrames and sizeLetters(1) (must be smaller as nFrames)             doubleDropRattio = 0.5; % ratios of columns with 2 drops per loop instad of just 1             DelayTime = 1/10; % in sec             xLimits = [0 500]; % in pixel             yLimits = [0 400]; % in pixel             snapshotAtFrame = 50;         case 2             rng(1) % seed random generator to make results reproducible             name = 'medium_letters';             nFrames = 150;             sizeLetters = [12 21]; % [nLetterRows nLetterColumns]             dropLength = 25; % should be adjusted with regard to nFrames and sizeLetters(1) (must be smaller as nFrames)             doubleDropRattio = 1; % ratios of columns with 2 drops per loop instad of just 1             DelayTime = 1/10; % in sec             xLimits = [0 500]; % in pixel             yLimits = [0 400]; % in pixel             snapshotAtFrame = 50;         case 3             rng(2) % seed random generator to make results reproducible             name = 'medium_letters_2';             nFrames = 191; % hight Least common multiple with 150; so combinations do no allign             sizeLetters = [12 21]; % [nLetterRows nLetterColumns]             dropLength = 25; % should be adjusted with regard to nFrames and sizeLetters(1) (must be smaller as nFrames)             doubleDropRattio = 1; % ratios of columns with 2 drops per loop instad of just 1             DelayTime = 1/10; % in sec             xLimits = [0 500]; % in pixel             yLimits = [0 400]; % in pixel             snapshotAtFrame = 50;         case 4             rng(3) % seed random generator to make results reproducible             name = 'medium_letters_3';             nFrames = 229;             sizeLetters = [12 21]; % [nLetterRows nLetterColumns]             dropLength = 25; % should be adjusted with regard to nFrames and sizeLetters(1) (must be smaller as nFrames)             doubleDropRattio = 1; % ratios of columns with 2 drops per loop instad of just 1             DelayTime = 1/10; % in sec             xLimits = [0 500]; % in pixel             yLimits = [0 400]; % in pixel             snapshotAtFrame = 50;         case 5             rng(4) % seed random generator to make results reproducible             name = 'medium_letters_4';             nFrames = 259;             sizeLetters = [12 21]; % [nLetterRows nLetterColumns]             dropLength = 25; % should be adjusted with regard to nFrames and sizeLetters(1) (must be smaller as nFrames)             doubleDropRattio = 1; % ratios of columns with 2 drops per loop instad of just 1             DelayTime = 1/10; % in sec             xLimits = [0 500]; % in pixel             yLimits = [0 400]; % in pixel             snapshotAtFrame = 50;         case 6             rng(1) % seed random generator to make results reproducible             name = 'big_letters';             nFrames = 60;             sizeLetters = [6 9]; % [nLetterRows nLetterColumns]             dropLength = 15; % should be adjusted with regard to nFrames and sizeLetters(1) (must be smaller as nFrames)             doubleDropRattio = 1; % ratios of columns with 2 drops per loop instad of just 1             DelayTime = 1/5; % in sec             xLimits = [0 400]; % in pixel             yLimits = [0 400]; % in pixel             snapshotAtFrame = 50;         otherwise             error('not defined')     end       figHandle = figure(1562134155);     clf     axesHandle = axes;     hold(axesHandle,'on')     set(figHandle, 'Units','pixel');     set(figHandle, 'Position',[1 1 xLimits(2) yLimits(2)]); % big start image for antialiasing later [x y width height]     set(axesHandle,'Color',[0 0 0]); % black background     set(axesHandle,'Position',[0 0 1 1]); % stretch axis as big as figure, [x y width height]     set(axesHandle,'XTick',NaN) % get rid of ticks     set(axesHandle,'YTick',NaN) % get rid of ticks     set(axesHandle,'TickLength',[0 0]) % get rid of ticks     set(axesHandle,'YColor',[0 0 0]) % remove outline     set(axesHandle,'XColor',[0 0 0]) % remove outline          xlim(xLimits);ylim(yLimits);          letterCube = repmat(randi(nChar,sizeLetters),1,1,nFrames);     for iRand = 1:numel(letterCube)*0.02 % small proportion of flipping symbols         letterRow = randi(sizeLetters(1)); % select random position         letterCol = randi(sizeLetters(2)); % select random position         letterThroughTime = letterCube(letterRow,letterCol,:); % extract         letterThroughTime = letterThroughTime(:)';         letterThroughTime(1:randi(round(nFrames/3)+3,1,2)) = randi(nChar); % add a random section         shift = randi(nFrames-1);         letterThroughTime = [letterThroughTime(shift+1:end) letterThroughTime(1:shift)]; % time offset         letterCube(letterRow,letterCol,:) = letterThroughTime; % write back     end       dropColMap = zeros(nFrames,3); % default Black     dropColMap(1:dropLength,:) = letterColMap(dropLength); % drop colors with black to fill the list up          glareColMap = zeros(nFrames,3); % default Black     glareColMap(1,:) = 1; % drop tip white          % for i=1:xLimits(2)     %     plot(i,100,'.','Color',map(i,:))     % end          xDelta = xLimits(2)/sizeLetters(2);     xCoordinates = (xDelta/2:xDelta:xLimits(2));          yDelta = yLimits(2)/sizeLetters(1);     yCoordinates = (yDelta/2:yDelta:yLimits(2))+yDelta/10;          handMat = NaN(sizeLetters);     for iRow = 1:sizeLetters(1)         for iCol = 1:sizeLetters(2)             handMat(iRow,iCol) = text(xCoordinates(iCol),yCoordinates(iRow),...                 charList(letterCube(iRow,iCol,1)),...                 'FontWeight','bold',...                 'FontName','monospaced',...                 'Color',[1 1 1],...                 'FontUnits','pixel',...                 'FontSize',yDelta*1.08,...                 'HorizontalAlignment','center',...                 'VerticalAlignment','middle');         end     end     stateMat = repmat((1:sizeLetters(1))' ,1, sizeLetters(2)); % initiate the basic rain drops running down the screen     stateOffset = randi(nFrames,1,sizeLetters(2)); % create a basic offsets for different delays     stateMat = stateMat + ones(sizeLetters(1),1) * stateOffset;               stateOffset = randi(round(nFrames/3),1,sizeLetters(2))+randi(round(nFrames/5),1,sizeLetters(2)); % create secondary offsets for different delays     stateOffset(rand(1,sizeLetters(2))>doubleDropRattio) = 0; % only a portion of columns get 2 drops     stateMat2 = stateMat + ones(sizeLetters(1),1) * stateOffset;          clearRGBimage = uint8(ones(yLimits(2),xLimits(2),3,nFrames)); % allocate     shineRGBimage = clearRGBimage;                                      % allocate       for iFrame = 1:nFrames                  stateMat  = rem(stateMat ,nFrames); % bring back into range [0 nFrames-1]         stateMat2 = rem(stateMat2,nFrames); % bring back into range [0 nFrames-1]                  for iRow = 1:sizeLetters(1)             for iCol = 1:sizeLetters(2)                 if stateMat(iRow,iCol)>stateMat2(iRow,iCol) % use the second drop                     set(handMat(iRow,iCol),'Color',dropColMap(stateMat2(iRow,iCol)+1,:),...                         'string',charList(nChar-letterCube(iRow,iCol,iFrame)+1)); % use a mirrored charList to get different characters                 else  % use the first drop                     set(handMat(iRow,iCol),'Color',dropColMap(stateMat(iRow,iCol)+1,:),...                         'string',charList(letterCube(iRow,iCol,iFrame)));                 end             end         end         drawnow         fClear = getframe(figHandle);                  % secondary image using only the white letters to generate extra strong glare         for iRow = 1:sizeLetters(1)             for iCol = 1:sizeLetters(2)                 if stateMat(iRow,iCol)>stateMat2(iRow,iCol) % use the second drop                     set(handMat(iRow,iCol),'Color',glareColMap(stateMat2(iRow,iCol)+1,:),...                         'string',charList(nChar-letterCube(iRow,iCol,iFrame)+1)); % use a mirrored charList to get different characters                 else  % use the first drop                     set(handMat(iRow,iCol),'Color',glareColMap(stateMat(iRow,iCol)+1,:),...                         'string',charList(letterCube(iRow,iCol,iFrame)));                 end             end         end         drawnow         fGlare = getframe(figHandle);                  stateMat  = stateMat +1; % move drops "one position down"         stateMat2 = stateMat2+1; % move drops "one position down"                  %% save animation         fClear.cdata = fliplr(fClear.cdata); % view from "behind the code"         fGlare.cdata = fliplr(fGlare.cdata); % view from "behind the code"                  weightFiddleMode = false; % for debugging ad adjusting                  if weightFiddleMode; figure(110); clf; imshow(fClear.cdata); end         fShine.cdata = imgaussfilt(fClear.cdata,yDelta/3); % far reaching shine of all letters         if weightFiddleMode; figure(111); clf; imshow(fShine.cdata); end         fShine.cdata = fShine.cdata*1.5; % make brighter (automatically limited to range by unit8 format)         if weightFiddleMode; figure(112); clf; imshow(fShine.cdata); end                  fEdge.cdata = imgaussfilt(fClear.cdata,yDelta/12); % stronger glow close to the letter edges         if weightFiddleMode; figure(113); clf; imshow(fEdge.cdata); end                  fEdge.cdata = fEdge.cdata*0.7; % make darker         if weightFiddleMode; figure(114); clf; imshow(fEdge.cdata); end                  fShine.cdata = imadd(fShine.cdata,fEdge.cdata); % combine shine and edge glow         if weightFiddleMode; figure(115); clf; imshow(fShine.cdata); end                           if weightFiddleMode; figure(116); clf; imshow(fGlare.cdata); end         fGlare.cdata = imgaussfilt(fGlare.cdata,yDelta/2); % far reaching shine of the white letter at the drop tip         if weightFiddleMode; figure(117); clf; imshow(fGlare.cdata); end         fGlare.cdata = fGlare.cdata*1.5; % make brighter (automatically limited to range by unit8 format)         if weightFiddleMode; figure(118); clf; imshow(fGlare.cdata); end                  fShine.cdata = imadd(fShine.cdata,fGlare.cdata); % combine; this makes the drop tip double bright         if weightFiddleMode; figure(119); clf; imshow(fShine.cdata); end                  fShine.cdata = imadd(fShine.cdata*0.8,fClear.cdata*0.5);  % combine shine with original sharp letters         if weightFiddleMode; figure(120); clf; imshow(fShine.cdata); end         if weightFiddleMode; return; end           clearRGBimage(:,:,:,iFrame) = fClear.cdata; % store         shineRGBimage(:,:,:,iFrame) = fShine.cdata; % store                  if snapshotAtFrame == iFrame             imwrite(fClear.cdata,fullfile(pathstr, [fname '_' name '_clear.png'])) % save png (native RGB no colormap)             imwrite(fShine.cdata,fullfile(pathstr, [fname '_' name '_shine.png'])) % save png (native RGB no colormap)         end     end           colormapImage = permute(clearRGBimage(:,:,:,:),[1 2 4 3]); % step1; make unified image     colormapImage = reshape(colormapImage, yLimits(2),xLimits(2)*nFrames,3,1); % step2; make unified image     mapClear = createImMap(colormapImage,64,[0 0 0; 1 1 1]); % colormap     colormapImage = permute(shineRGBimage(:,:,:,:),[1 2 4 3]); % step1; make unified image     colormapImage = reshape(colormapImage, yLimits(2),xLimits(2)*nFrames,3,1); % step2; make unified image     mapShine = createImMap(colormapImage,128,[0 0 0; 1 1 1]); % colormap          imClear = uint8(ones(yLimits(2),xLimits(2),1,nFrames)); % allocate     imShine = uint8(ones(yLimits(2),xLimits(2),1,nFrames)); % allocate     for iFrame = 1:nFrames         imClear(:,:,1,iFrame) = rgb2ind(clearRGBimage(:,:,:,iFrame),mapClear); % ,'nodither');         imShine(:,:,1,iFrame) = rgb2ind(shineRGBimage(:,:,:,iFrame),mapShine); % ,'nodither');     end          imwrite(imClear,mapClear,fullfile(pathstr, [fname '_' name '_clear.gif']),'DelayTime',DelayTime,'LoopCount',inf) % save gif         imwrite(imShine,mapShine,fullfile(pathstr, [fname '_' name '_shine.gif']),'DelayTime',DelayTime,'LoopCount',inf) % save gif         disp([fname '_' name '_clear.gif  has ' num2str(numel(imClear)/10^6 ,4) ' Megapixels']) % Category:Animated GIF files exceeding the 50 MP limit end   function map = letterColMap(nCol) %  map: % Pos 1:  white (short burst) % a: bright green changing to green % b: staying green () % c: fading to black   querries = linspace(0,100,nCol-1);   x = [0   15   40   100]; % percent of map %      a    b    c  red = interp1(x,...      [0.4  0.0  0.0   0],... intensity     querries); blue = interp1(x,...      [0.4  0.0  0.0   0],... intensity     querries); green = interp1(x,...      [1   0.8   0.8   0],... intensity     querries);   map = [ [1 1 1];red(:) green(:) blue(:)]; % white in front   function map = createImMap(imRGB,nCol,startMap) % createImMap creates a color-map including predefined colors. % "rgb2ind" creates a map but there is no option to predefine some colors, %         and it does not handle stacked images. % Input: %   imRGB:     image, [imRows x imColumns x 3(RGB) x nStack] (unit8) %   nCol:      total number of colors the map should have, [integer] %   startMap:  predefined colors; colormap format, [p x 3] (double)  imRGB = permute(imRGB,[1 2 4 3]); % step1; make unified column-image (handling possible nStack) imRGBcolumn = reshape(imRGB,[],1,3,1); % step2; make unified column-image  fullMap = double(permute(imRGBcolumn,[1 3 2]))./255; % "column image" to color map  [fullMap,~,imMapColumn] = unique(fullMap,'rows'); % find all unique colors; create indexed colormap-image % "cmunique" could be used but is buggy and inconvenient because the output changes between "uint8" and "double"  nColFul = size(fullMap,1); nColStart = size(startMap,1); disp(['Number of colors: ' num2str(nColFul) ' (including ' num2str(nColStart) ' self defined)']);  if nCol<=nColStart;  error('Not enough colors');        end if nCol>nColFul;   warning('More colors than needed');  end  isPreDefCol = false(size(imMapColumn)); % init   for iCol = 1:nColStart     diff = sum(abs(fullMap-repmat(startMap(iCol,:),nColFul,1)),2); % difference between a predefined and all colors     [mDiff,index] = min(diff); % find matching (or most similar) color     if mDiff>0.05 % color handling is not precise         warning(['Predefined color ' num2str(iCol) ' does not appear in image'])         continue     end     isThisPreDefCol = imMapColumn==index; % find all pixel with predefined color     disp([num2str(sum(isThisPreDefCol(:))) ' pixel have predefined color ' num2str(iCol)]);     isPreDefCol = or(isPreDefCol,isThisPreDefCol); % combine with overall list end [~,mapAdditional] = rgb2ind(imRGBcolumn(~isPreDefCol,:,:),nCol-nColStart,'nodither'); % create map of remaining colors map = [startMap;mapAdditional];