/usr/share/psychtoolbox-3/PsychDemos/VideoTextureExtractionDemo.m is in psychtoolbox-3-common 3.0.11.20131230.dfsg1-1build1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 | function VideoTextureExtractionDemo(lightson, objtype, multiMarker)
% Use ARToolkit to track and visualize 3D objects in live-video.
%
% Usage: ARToolkitDemo([lightson = 0][, objtype = 3][, multiMarker = 2])
%
% Minimalistic demo on how to capture video data and use ARToolkit to
% detect and track the rigid position and orientation of markers, then
% visualize corresponding 3D objects on top of video via OpenGL.
%
% Parameters:
%
% multiMarker = If set to 2 (default), track single markers. If set to 1,
% track so called multi markers or composite markers for more robustness
% against occlusion of single markers. A setting of 3 (=1+2) should track
% both types of markers simultaneously, but this doesn't seem to work well
% yet.
%
% History:
% 19.04.2009 mk First prototype written.
global GL;
global sizeMM;
% Running on PTB-3? Hopefully...
AssertOpenGL;
% Size of rendered objects in millimeters:
sizeMM = 40; %#ok<NASGU>
if nargin < 1
lightson = [];
end
if isempty(lightson)
lightson = 0;
end
if nargin < 2
objtype = [];
end
if isempty(objtype)
objtype = 3;
end
try
% No sync tests for this simple demo:
olsync = Screen('Preference', 'SkipSyncTests', 2);
InitializeMatlabOpenGL;
% Open onscreen window for diplay:
screenid = max(Screen('Screens'));
% Size of window: Default to fullscreen:
if objtype ~= 3
roi = CenterRect(1.5 * [0 0 640 480], Screen('Rect',screenid));
else
roi = [];
end
% Use imaging pipeline to flip image horizontally to avoid confusing
% the viewer due to mirror view:
PsychImaging('PrepareConfiguration');
PsychImaging('AddTask', 'General', 'UseFastOffscreenWindows');
PsychImaging('AddTask', 'AllViews', 'FlipHorizontal');
win = PsychImaging('OpenWindow', screenid, 0, roi);
% Open videocapture device: For now we use engine 2, the ARVideo
% engine, to simplify compatibility issues...
imgFormat = [];
engineId = 0;
switch engineId
case 2,
grabber = Screen('OpenVideoCapture', win, 0, [], 5, [], [], [], [], engineId);
case 0,
devid = PsychGetCamIdForSpec('Eye');
grabber = Screen('OpenVideoCapture', win, devid, [], 1, [], [], [], [], engineId);
% imgFormat = 4;
case 1,
grabber = Screen('OpenVideoCapture', win, 0, [0 0 640 480], [], [], [], [], [], engineId);
otherwise
error('Unknown video capture engineId');
end
% Start capture with requested 30 fps:
Screen('StartVideoCapture', grabber, 30, 1);
% Get a single texture that we can query for the image format:
tex = Screen('GetCapturedImage', win, grabber);
[w, h] = Screen('WindowSize', tex) %#ok<NOPRT>
channels = Screen('PixelSize', tex) / 8 %#ok<NOPRT>
% Release texture after query:
Screen('Close', tex);
tex = []; %#ok<NASGU>
% Debug level for tracker:
PsychCV('Verbosity', 3);
% Initialize ARToolkit: Load camera calibration data, assign image size
% and properties for raw video input images:
ardata = [ PsychtoolboxRoot 'PsychDemos/ARToolkitDemoData/' ];
PsychCV('ARRenderSettings', [], [], 2000);
% ON OS/X:
%
% imgFormat == 4 fuer Quicktime 0,4 channel or ARVideo 0,4 channel.
% imgFormat == [] or 7 fuer ARVideo 5 channels (aka 4 channels swizzled).
% imgFormat == [] or 1 fuer Quicktime or ARVideo 3 channels.
% imgFormat == [] or 6 fuer Quicktime 1,2 channels.
% imgFormat == [] fuer Firewire 0,1,2,3,4 channels.
[imgbuffer, projectionMatrix, debugimagebuffer] = PsychCV('ARInitialize', [ardata 'camera_para.dat'], w, h, channels, imgFormat); %#ok<NASGU>
% [templateMatchingInColor, imageProcessingFullSized, imageProcessingIdeal, trackingWithPCA] = PsychCV('ARTrackerSettings')
% Single markers by default:
if nargin < 3
multiMarker = 2;
end
% Load our (multi-)marker(s):
% Need to cd() into marker directory, as some paths inside the marker
% config files are coded relative to working directory :-(
olddir = pwd;
try
marker = [];
if bitand(multiMarker, 2)
cd(ardata);
% marker(end+1) = PsychCV('ARLoadMarker', 'patt.sample2', 0, 40);
% marker(end+1) = PsychCV('ARLoadMarker', 'patt.hiro', 0);
marker(end+1) = PsychCV('ARLoadMarker', 'patt.kanji', 0, 40);
end
if bitand(multiMarker, 1)
cd([ ardata 'multi/' ]);
marker(end+1) = PsychCV('ARLoadMarker', 'marker.dat', 1); %#ok<NASGU>
end
catch
end
cd(olddir);
if objtype == 3
% Setup our 3D dense OpenGL head model for mirroring -- Our "Avatar":
MFHeadmodel('Initialize', win);
% Enable lighting model for head rendering:
MFHeadmodel('SetLighting', 0);
% Load OBJ's and initialize morph & render engine:
CGHeadModelFile = 'CGHeadModels/TwentySevenCGKeyExpressions/TwentySevenCGKeyExpressions.mat';
ExpressionsCount = MFHeadmodel('LoadModels', sprintf('%s%s', MFData, CGHeadModelFile)); %#ok<NASGU>
% Compute nonrigid facial expression morph for this frame:
morphWeights = 1;
MFHeadmodel('MorphHead', morphWeights);
texprops = MFHeadmodel('GetModelTextureProperties') %#ok<NOPRT>
texResolution = texprops.texResolution;
texSize = max(texResolution);
texCoordMin = texprops.texCoordMin;
texCoordMax = texprops.texCoordMax;
texSize = 512;
texScale = texSize / max(texResolution);
texCoordMin = [0, 0];
texCoordMax = [texSize, texSize];
texResolution = [texSize, texSize];
else
texSize = 512;
texCoordMin = [0, 0];
texCoordMax = [texSize, texSize];
texResolution = [texSize, texSize];
end
% zThreshold may need tweaking for depth range of object:
zThreshold = 0.000001;
callbackEvalString = 'glCallList(gld);';
context = moglExtractTexture('CreateContext', win, [0 0 w h], texCoordMin, texCoordMax, texResolution, zThreshold);
context = moglExtractTexture('SetRenderCallback', context, callbackEvalString);
% Setup OpenGL 3D rendering for our simple test:
Screen('BeginOpenGL', win);
% Enable lighting and depth-test:
glColor3f(1,1,1);
if lightson
glEnable(GL.LIGHTING);
end
glEnable(GL.LIGHT0);
glEnable(GL.DEPTH_TEST);
% Set projection matrix to one provided by ARToolkit:
glMatrixMode(GL.PROJECTION);
glLoadIdentity;
glLoadMatrixd(projectionMatrix);
% Init modelview matrix to identity: Will be overwritten, reloaded on
% each object draw operation by modelview matrix from ARToolkit:
glMatrixMode(GL.MODELVIEW);
glLoadIdentity;
% Position lightsource:
glLightfv(GL.LIGHT0,GL.POSITION,[ 1 2 3 0 ]);
% Define background clearcolor etc.:
glClearColor(0,0,0,0);
glClear;
% Absolutely crucial that alpha blending is "off"!
glDisable(GL.BLEND);
% Build display list with static texture extraction 3D object:
gld = glGenLists(1);
glNewList(gld, GL.COMPILE);
texmin = 0.00;
texmax = 1.00;
glPushMatrix;
switch(objtype)
case 1,
glTranslated(-sizeMM/2, -sizeMM/2, 0);
glTranslated(0, -sizeMM, 0);
glBegin(GL.QUADS);
glTexCoord2f(texmin, texmin);
glVertex2f(0.0, 0.0);
glTexCoord2f(texmin, texmax);
glVertex2f(0.0, 1.0 * sizeMM);
glTexCoord2f(texmax, texmax);
glVertex2f(1.0 * sizeMM, 1.0 * sizeMM);
glTexCoord2f(texmax, texmin);
glVertex2f(1.0 * sizeMM, 0.0);
glEnd;
case 2,
glTranslated(-sizeMM/2, -sizeMM/2, 0);
mysphere = gluNewQuadric;
gluQuadricTexture(mysphere, GL.TRUE);
glMatrixMode(GL.TEXTURE);
glPushMatrix;
glLoadIdentity;
glScaled(texSize, texSize, 1);
gluSphere(mysphere, sizeMM, 100, 100);
glPopMatrix;
glMatrixMode(GL.MODELVIEW);
gluDeleteQuadric(mysphere);
case 3,
glTranslated(0, 1*sizeMM, 0);
glRotated(180, 0, 0, 1);
glMatrixMode(GL.TEXTURE);
glPushMatrix;
glLoadIdentity;
glScaled(texScale, texScale, 1);
moglmorpher('render');
glPopMatrix;
glMatrixMode(GL.MODELVIEW);
end
glPopMatrix;
glEndList;
% OpenGL 3D setup done:
Screen('EndOpenGL', win);
% Shutdown head renderer: We can release the MFHeadmodels ressources
% here already, because we only need 1 static "neutral expression"
% shape, which we stored conveniently into a GL display list above :-)
MFHeadmodel('Shutdown');
% Init segmentation gain to 50% of avg image intensity:
gain = 0.5;
SetMouse(gain * Screen('WindowSize', win)/2, 100);
count = 0;
t=GetSecs;
KbReleaseWait;
inImage = [];
texBuffer = [];
doExtract = 0;
buttons = [0 0 0];
% Run tracking and viz loop until keypress:
while ~buttons(2)
% Update image segmentation gain from horizontal mouse position:
[xm, ym, buttons] = GetMouse;
gain = 2 * xm / Screen('WindowSize', win);
if xm == 0 && ym == 0
break;
end
if buttons(1) && ~oldbuttons
doExtract = 1 - doExtract;
end
oldbuttons = buttons(1);
% Retrieve next captured image. The 'waitforImage=2' waits for a
% new image, but disables texture creation, so 'dummy' is actually
% an empty handle. The 'specialMode'=4 flag requests video data to
% be put into the PsychCV() memory buffer referenced by
% 'imgbuffer'. 'imgIntensity' returns the average image intensity -
% Useful for computing an adaptive image segmentation threshold:
[inImage pts nrdropped imgIntensity] = Screen('GetCapturedImage', win, grabber, 1, inImage, 4, imgbuffer);
% Define dynamic threshold for image segmentation:
thresh = max(min(imgIntensity * gain, 254), 1);
% ARToolkit processing:
detectedMarkers = PsychCV('ARDetectMarkers', [], thresh);
% Visualize detected objects in 3D mode:
Screen('BeginOpenGL', win);
% Clear z-buffer for proper occlusion handling:
glClear(GL.DEPTH_BUFFER_BIT);
% Render current video image as backdrop:
PsychCV('ARRenderImage');
% For each candidate marker do...
for i=1:length(detectedMarkers)
% i'th candidate detected reliably?
merr = detectedMarkers(i).MatchError;
if merr < realmax
% Yes: Draw 3D object corresponding to i'th pattern:
mpos = detectedMarkers(i).ModelViewMatrix(1:3, 4);
statusTxt = sprintf('POS X = %04f Y = %04f Z = %04f', mpos(1), mpos(2), mpos(3));
DrawFormattedText(win, statusTxt, 'center', 0, [255 0 0], [], 1);
% Setup rigid position and orientation via 4x4 xform matrix:
glLoadMatrixd(detectedMarkers(i).ModelViewMatrix);
if doExtract
% Perform texture extraction pass from input video image:
[texBuffer, texId, texTarget] = moglExtractTexture('Extract', context, inImage, 0);
else
% Perform regular render pass:
if isempty(texBuffer)
glCallList(gld);
end
end
% Rerender:
if ~isempty(texBuffer)
if objtype ~= 3
glTranslatef(2.2*sizeMM, 0, 0);
end
glEnable(texTarget);
glBindTexture(texTarget, texId);
glCallList(gld);
glBindTexture(texTarget, 0);
glDisable(texTarget);
end
end
end
% Done with objects:
Screen('EndOpenGL', win);
if doExtract && ~isempty(texBuffer)
% Draw extracted texture:
% Screen('DrawTexture', win, texBuffer);
end
% if ~isempty(texBuffer)
% % Close previously extracted texture:
% Screen('Close', texBuffer);
% texBuffer = [];
% end
% Show updated image at next retrace:
Screen('Flip', win, 0, 0, 1);
% Next tracking loop iteration...
count = count + 1;
end;
telapsed = GetSecs - t;
moglExtractTexture('DestroyContext', context);
% Shutdown head renderer:
MFHeadmodel('Shutdown');
% Stop capture, close engine and onscreen window:
Screen('StopVideoCapture', grabber);
Screen('CloseVideoCapture', grabber);
Screen('CloseAll');
% Shutdown tracker:
PsychCV('ARShutdown');
% Stats...
avgfps = count / telapsed %#ok<NOPRT,NASGU>
catch
Screen('CloseAll');
PsychCV('ARShutdown');
end;
% Restore sync settings:
Screen('Preference', 'SkipSyncTests', olsync);
return
end
function MCalib = computeRigidXForm(MTarget, MHandle)
TTarget = MTarget(1:3, 4);
RTarget = MTarget(1:3, 1:3);
% Tinverse is the 4x4 translation matrix with the negated
% (inverted) T ranslation vector of the tracking target:
Tinverse = diag([1 1 1 1]);
Tinverse(1:3, 4) = -TTarget;
% Rinverse is the transpose (==inverse) of the tracking targets
% rotation matrix RTarget, extended to a 4x4 matrix:
Rinverse = diag([1 1 1 1]);
Rinverse(1:3, 1:3) = transpose(RTarget);
% Build final inverse transformation:
MTargetInverse = Rinverse * Tinverse;
% Build combined forward transformation:
MCalib = MTargetInverse * MHandle;
return;
end
|