aboutsummaryrefslogtreecommitdiff
path: root/webrtc/modules/video_processing/test/createTable.m
diff options
context:
space:
mode:
Diffstat (limited to 'webrtc/modules/video_processing/test/createTable.m')
-rw-r--r--webrtc/modules/video_processing/test/createTable.m179
1 files changed, 179 insertions, 0 deletions
diff --git a/webrtc/modules/video_processing/test/createTable.m b/webrtc/modules/video_processing/test/createTable.m
new file mode 100644
index 0000000000..fe8777ee71
--- /dev/null
+++ b/webrtc/modules/video_processing/test/createTable.m
@@ -0,0 +1,179 @@
+% Create the color enhancement look-up table and write it to
+% file colorEnhancementTable.cpp. Copy contents of that file into
+% the source file for the color enhancement function.
+
+clear
+close all
+
+
+% First, define the color enhancement in a normalized domain
+
+% Compander function is defined in three radial zones.
+% 1. From 0 to radius r0, the compander function
+% is a second-order polynomial intersecting the points (0,0)
+% and (r0, r0), and with a slope B in (0,0).
+% 2. From r0 to r1, the compander is a third-order polynomial
+% intersecting the points (r0, r0) and (r1, r1), and with the
+% same slope as the first part in the point (r0, r0) and slope
+% equal to 1 in (r1, r1).
+% 3. For radii larger than r1, the compander function is the
+% unity scale function (no scaling at all).
+
+r0=0.07; % Dead zone radius (must be > 0)
+r1=0.6; % Enhancement zone radius (must be > r0 and < 1)
+B=0.2; % initial slope of compander function (between 0 and 1)
+
+x0=linspace(0,r0).'; % zone 1
+x1=linspace(r0,r1).'; % zone 2
+x2=linspace(r1,1).'; % zone 3
+
+A=(1-B)/r0;
+f0=A*x0.^2+B*x0; % compander function in zone 1
+
+% equation system for finding second zone parameters
+M=[r0^3 r0^2 r0 1;
+ 3*r0^2 2*r0 1 0;
+ 3*r1^2 2*r1 1 0;
+ r1^3 r1^2 r1 1];
+m=[A*r0^2+B*r0; 2*A*r0+B; 1; r1];
+% solve equations
+theta=M\m;
+
+% compander function in zone 1
+f1=[x1.^3 x1.^2 x1 ones(size(x1))]*theta;
+
+x=[x0; x1; x2];
+f=[f0; f1; x2];
+
+% plot it
+figure(1)
+plot(x,f,x,x,':')
+xlabel('Normalized radius')
+ylabel('Modified radius')
+
+
+% Now, create the look-up table in the integer color space
+[U,V]=meshgrid(0:255, 0:255); % U-V space
+U0=U;
+V0=V;
+
+% Conversion matrix from normalized YUV to RGB
+T=[1 0 1.13983; 1 -0.39465 -0.58060; 1 2.03211 0];
+Ylum=0.5;
+
+figure(2)
+Z(:,:,1)=Ylum + (U-127)/256*T(1,2) + (V-127)/256*T(1,3);
+Z(:,:,2)=Ylum + (U-127)/256*T(2,2) + (V-127)/256*T(2,3);
+Z(:,:,3)=Ylum + (U-127)/256*T(3,2) + (V-127)/256*T(3,3);
+Z=max(Z,0);
+Z=min(Z,1);
+subplot(121)
+image(Z);
+axis square
+axis off
+set(gcf,'color','k')
+
+R = sqrt((U-127).^2 + (V-127).^2);
+Rnorm = R/127;
+RnormMod = Rnorm;
+RnormMod(RnormMod==0)=1; % avoid division with zero
+
+% find indices to pixels in dead-zone (zone 1)
+ix=find(Rnorm<=r0);
+scaleMatrix = (A*Rnorm(ix).^2 + B*Rnorm(ix))./RnormMod(ix);
+U(ix)=(U(ix)-127).*scaleMatrix+127;
+V(ix)=(V(ix)-127).*scaleMatrix+127;
+
+% find indices to pixels in zone 2
+ix=find(Rnorm>r0 & Rnorm<=r1);
+scaleMatrix = (theta(1)*Rnorm(ix).^3 + theta(2)*Rnorm(ix).^2 + ...
+ theta(3)*Rnorm(ix) + theta(4)) ./ RnormMod(ix);
+U(ix)=(U(ix)-127).*scaleMatrix + 127;
+V(ix)=(V(ix)-127).*scaleMatrix + 127;
+
+% round to integer values and saturate
+U=round(U);
+V=round(V);
+U=max(min(U,255),0);
+V=max(min(V,255),0);
+
+Z(:,:,1)=Ylum + (U-127)/256*T(1,2) + (V-127)/256*T(1,3);
+Z(:,:,2)=Ylum + (U-127)/256*T(2,2) + (V-127)/256*T(2,3);
+Z(:,:,3)=Ylum + (U-127)/256*T(3,2) + (V-127)/256*T(3,3);
+Z=max(Z,0);
+Z=min(Z,1);
+subplot(122)
+image(Z);
+axis square
+axis off
+
+figure(3)
+subplot(121)
+mesh(U-U0)
+subplot(122)
+mesh(V-V0)
+
+
+
+% Last, write to file
+% Write only one matrix, since U=V'
+
+fid = fopen('../out/Debug/colorEnhancementTable.h','wt');
+if fid==-1
+ error('Cannot open file colorEnhancementTable.cpp');
+end
+
+fprintf(fid,'//colorEnhancementTable.h\n\n');
+fprintf(fid,'//Copy the constant table to the appropriate header file.\n\n');
+
+fprintf(fid,'//Table created with Matlab script createTable.m\n\n');
+fprintf(fid,'//Usage:\n');
+fprintf(fid,'// Umod=colorTable[U][V]\n');
+fprintf(fid,'// Vmod=colorTable[V][U]\n');
+
+fprintf(fid,'static unsigned char colorTable[%i][%i] = {\n', size(U,1), size(U,2));
+
+for u=1:size(U,2)
+ fprintf(fid,' {%i', U(1,u));
+ for v=2:size(U,1)
+ fprintf(fid,', %i', U(v,u));
+ end
+ fprintf(fid,'}');
+ if u<size(U,2)
+ fprintf(fid,',');
+ end
+ fprintf(fid,'\n');
+end
+fprintf(fid,'};\n\n');
+fclose(fid);
+fprintf('done');
+
+
+answ=input('Create test vector (takes some time...)? y/n : ','s');
+if answ ~= 'y'
+ return
+end
+
+% Also, create test vectors
+
+% Read test file foreman.yuv
+fprintf('Reading test file...')
+[y,u,v]=readYUV420file('../out/Debug/testFiles/foreman_cif.yuv',352,288);
+fprintf(' done\n');
+unew=uint8(zeros(size(u)));
+vnew=uint8(zeros(size(v)));
+
+% traverse all frames
+for k=1:size(y,3)
+ fprintf('Frame %i\n', k);
+ for r=1:size(u,1)
+ for c=1:size(u,2)
+ unew(r,c,k) = uint8(U(double(v(r,c,k))+1, double(u(r,c,k))+1));
+ vnew(r,c,k) = uint8(V(double(v(r,c,k))+1, double(u(r,c,k))+1));
+ end
+ end
+end
+
+fprintf('\nWriting modified test file...')
+writeYUV420file('../out/Debug/foremanColorEnhanced.yuv',y,unew,vnew);
+fprintf(' done\n');