added hue example images

Author: vadimkantorov

examples/computeColor.m

@@ -0,0 +1,115 @@
+function img = computeColor(u,v)
+
+%   computeColor color codes flow field U, V
+
+%   According to the c++ source code of Daniel Scharstein 
+%   Contact: [email protected]
+
+%   Author: Deqing Sun, Department of Computer Science, Brown University
+%   Contact: [email protected]
+%   $Date: 2007-10-31 21:20:30 (Wed, 31 Oct 2006) $
+
+% Copyright 2007, Deqing Sun.
+%
+%                         All Rights Reserved
+%
+% Permission to use, copy, modify, and distribute this software and its
+% documentation for any purpose other than its incorporation into a
+% commercial product is hereby granted without fee, provided that the
+% above copyright notice appear in all copies and that both that
+% copyright notice and this permission notice appear in supporting
+% documentation, and that the name of the author and Brown University not be used in
+% advertising or publicity pertaining to distribution of the software
+% without specific, written prior permission.
+%
+% THE AUTHOR AND BROWN UNIVERSITY DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+% INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR ANY
+% PARTICULAR PURPOSE.  IN NO EVENT SHALL THE AUTHOR OR BROWN UNIVERSITY BE LIABLE FOR
+% ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+% WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+% ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+% OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 
+
+nanIdx = isnan(u) | isnan(v);
+u(nanIdx) = 0;
+v(nanIdx) = 0;
+
+colorwheel = makeColorwheel();
+ncols = size(colorwheel, 1);
+
+rad = sqrt(u.^2+v.^2);          
+
+a = atan2(-v, -u)/pi;
+
+fk = (a+1) /2 * (ncols-1) + 1;  % -1~1 maped to 1~ncols
+   
+k0 = floor(fk);                 % 1, 2, ..., ncols
+
+k1 = k0+1;
+k1(k1==ncols+1) = 1;
+
+f = fk - k0;
+
+for i = 1:size(colorwheel,2)
+    tmp = colorwheel(:,i);
+    col0 = tmp(k0)/255;
+    col1 = tmp(k1)/255;
+    col = (1-f).*col0 + f.*col1;   
+   
+    idx = rad <= 1;   
+    col(idx) = 1-rad(idx).*(1-col(idx));    % increase saturation with radius
+    
+    col(~idx) = col(~idx)*0.75;             % out of range
+    
+    img(:,:, i) = uint8(floor(255*col.*(1-nanIdx)));         
+end;    
+
+%%
+function colorwheel = makeColorwheel()
+
+%   color encoding scheme
+
+%   adapted from the color circle idea described at
+%   http://members.shaw.ca/quadibloc/other/colint.htm
+
+
+RY = 15;
+YG = 6;
+GC = 4;
+CB = 11;
+BM = 13;
+MR = 6;
+
+ncols = RY + YG + GC + CB + BM + MR;
+
+colorwheel = zeros(ncols, 3); % r g b
+
+col = 0;
+%RY
+colorwheel(1:RY, 1) = 255;
+colorwheel(1:RY, 2) = floor(255*(0:RY-1)/RY)';
+col = col+RY;
+
+%YG
+colorwheel(col+(1:YG), 1) = 255 - floor(255*(0:YG-1)/YG)';
+colorwheel(col+(1:YG), 2) = 255;
+col = col+YG;
+
+%GC
+colorwheel(col+(1:GC), 2) = 255;
+colorwheel(col+(1:GC), 3) = floor(255*(0:GC-1)/GC)';
+col = col+GC;
+
+%CB
+colorwheel(col+(1:CB), 2) = 255 - floor(255*(0:CB-1)/CB)';
+colorwheel(col+(1:CB), 3) = 255;
+col = col+CB;
+
+%BM
+colorwheel(col+(1:BM), 3) = 255;
+colorwheel(col+(1:BM), 1) = floor(255*(0:BM-1)/BM)';
+col = col+BM;
+
+%MR
+colorwheel(col+(1:MR), 3) = 255 - floor(255*(0:MR-1)/MR)';
+colorwheel(col+(1:MR), 1) = 255;

examples/mpi_sintel_final_alley_1_vis_hue_examples/000003.png

@@ -1,5 +1,5 @@
 % The script requires the training sequences of the MPI Sintel dataset (http://sintel.is.tue.mpg.de/).
-% flowToColor is originally part of the MPI Sintel's bundler.
+% flowToColor and computeColor are originally part of the MPI Sintel's bundler.
 % The script has originally been used to produce visualizations for https://github.com/vadimkantorov/mpegflow/blob/master/README.md, but you could use it on other videos by adjusting VIDEO_PATH
 
 VIDEO_PATH = 'mpi_sintel_final_alley_1.avi';
@@ -15,7 +15,7 @@
     if isempty(frameIndex_rows_cols)
         break
     end
-        
+
     dxdy = fscanf(f, '%d ', fliplr(frameIndex_rows_cols(2:end)'))';
     flow = cat(3, dxdy(1:size(dxdy, 1) / 2, :), dxdy(size(dxdy, 1) / 2 + 1 : end, :));
     img = flowToColor(flow);