% Calibration routine for SMI IViewX eyetracker and Psychtoolbox, % using the serial port for communication. This function validates % a previous calibration. It's generally a good idea to pass the % exact same params struct here as you provided to calibrateEyeTracker. % NB, MeanDevXY is in deg visual angle, so is completely dependent on % you appropriately configuring IViewX settings to match your setup. The % other values are in pixels. % Currently only reports validation parameters for the left eye if tracking % binocular. As near as I can tell, this information is never transmitted, % so little can be done at this end. % Syntax: % [success,RMSdev,RMSdevdist,MeanDevXY] = validateCalibration(window,ET_serial,ET_params) % Inputs (all params are optional): % window - Psychtoolbox screen handle % ET_serial - Opened serial port object for scanner. % ET_params - struct with eye tracking parameters. All are optional. % npoints - (13) calibration points. DO NOT change between calib and % validation. % bgcolour - ([128 128 128]) background colour (RGB) % targcolour - ([255 255 255]) target colour (RGB) % targsize - (20) target height/width in pixels % acceptkey - ([spacebar]) key for forcing point acceptance % quitkey - ([escapekey]) key for aborting calibration % Use KbName('UnifyKeyNames') to get names for other keys % 13/4/2010 J Carlin function [ready,RMSdev, RMSdevdist, MeanDevXY] = validateCalibration(window,ET_serial,ET_params) % If no serial object entered, crash out if ~exist('ET_serial','var') || isempty(ET_serial) error('ET_serial must be defined! See calibrateEyeTracker') end % By default, calls time out in 10 SECONDS. % This is clearly unacceptably slow for our % purposes. Now 100 ms. set(ET_serial,'timeout',.1); % The downside is that Matlab spits out a lot of % warnings. Let's disable these... wstate=warning('off','MATLAB:serial:fgetl:unsuccessfulRead'); % If you don't know what you want, we will fill this in with % defaults. if ~exist('ET_params','var') ET_params = struct; end % Screen settings sc = Screen('Resolution',window); schw = [sc.width sc.height]; KbName('UnifyKeyNames'); % These are the default settings default_params = struct(... 'bgcolour',[128 128 128],... 'targcolour',[255 255 255],... 'targsize',20, ... 'npoints',13, ... 'acceptkey',KbName('space'), ... 'quitkey',KbName('escape') ... ); % Now put in defaults for whatever was left undefined fns = fieldnames(default_params); for fn = fns' if ~isfield(ET_params,fn{1}) ET_params.(fn{1}) = default_params.(fn{1}); end end % Draw background Screen(window,'FillRect',ET_params.bgcolour); % Display settings for targets % Make a cross - studiously avoiding alpha blending here to % maximise compatibility (but you will need to im processing toolbox) % Settings cross_orgsize = 100; cross_linewidth = .05; % Build cross cs = round((cross_orgsize / 2) - (cross_orgsize * cross_linewidth)); ce = round((cross_orgsize / 2) + (cross_orgsize * cross_linewidth)); cr = zeros(cross_orgsize); cr(:,cs:ce) = 1; cr(cs:ce,:) = 1; % Resize - Since square, no point to bicubic interpolation cr_rs = imresize(cr,[ET_params.targsize ET_params.targsize],'nearest'); % Make target uint8, colour rgb_t = ET_params.targcolour; cros = uint8(cat(3,cr_rs*rgb_t(1),cr_rs*rgb_t(2),cr_rs*rgb_t(3))); % Make an appropriately-coloured background rgb = ET_params.bgcolour; bg = uint8(ones(ET_params.targsize)); bg_rgb =cat(3,bg*rgb(1),bg*rgb(2),bg*rgb(3)); % Put background and target together target = bg_rgb; target(find(cros)) = cros(find(cros)); % Draw texture targetbuf = Screen('MakeTexture',window,target); % Set up basic rect targetrect = [0 0 size(target,1) size(target,2)]; % Start validation fprintf(ET_serial,sprintf('ET_VLS')); ready = 0; readyonce = 0; % Extra check to catch second eye in bino mode ntries = 0; points = zeros(ET_params.npoints,2); % Initialise output vars for graceful errors RMSdev = []; RMSdevdist = []; MeanDevXY = []; rc = 0; while ~ready ntries = ntries+1; % If no connection with serial, return anyway if ntries > 500 fprintf('Serial port communication failure!\n') break end % Check for manual attempts to move things along [keyisdown, secs, keyCode] = KbCheck; if keyisdown k = find(keyCode); k = k(1); % Force acceptance of current point if k == ET_params.acceptkey fprintf('Accepting point...\n') %WaitSecs(.2); % Time to let go of key... % Now stop execution until the key is released while KbCheck WaitSecs(.01); end fprintf(ET_serial,'ET_ACC'); % Give up on calibration elseif k == ET_params.quitkey fprintf('Calibration attempt aborted!\n') fprintf(ET_serial,'ET_BRK'); break end end % Ensure a second run through after receiving the first % ET_VLS return, so that we catch the second eye too. if readyonce ready = 1; end % Check if the eye tracker has something to say response = fgetl(ET_serial); % What might the eye tracker have to say? if ~isempty(response) % Save each response - mainly for debugging rc = rc+1; resplog{rc} = response; % Split by spaces command_etc = strread(regexprep(response,' ',' '),'%s'); command = command_etc{1}; %%% What we do next depends on the command we got: % Calibration point change if strcmp(command,'ET_CHG') % Coordinates for point xy = points(str2num(command_etc{2}),:); % Rect for point pointrect = CenterRectOnPoint(targetrect,xy(1),xy(2)); % Draw into rect Screen('DrawTexture',window,targetbuf,[],pointrect); Screen(window,'Flip'); % Reset timeout counter ntries = 0; % Calibation point definition elseif strcmp(command,'ET_PNT') points(str2num(command_etc{2}),:) = ... [str2num(command_etc{3}) str2num(command_etc{4})]; % Screen size verification %elseif strcmp(command,'ET_CSZ') % Actually, we don't want calibration area % to match screen size. % So arguments are X and Y size %sc = Screen('Resolution',window); %if str2num(command_etc{2}) ~= sc.width %fprintf('Calibration failed - Screen width mismatch\n') %break %elseif str2num(command_etc{3}) ~= sc.height %fprintf('Calibration failed - Screen height mismatch\n') %break %end % Validation finished % The twist here is that ET_VLS returns twice if % in binocular mode... So need to go through a last % check after finishing this. elseif strcmp(command,'ET_VLS') % Command_etc should now contain various numbers values = str2num(char(command_etc(3:5)))'; % SMI for some reason insists on including a degree % symbol for the last 2, which complicates things... values(end+1) = str2num(command_etc{6}(1:end-1)); values(end+1) = str2num(command_etc{7}(1:end-1)); if ~readyonce RMSdev = values(1:2); RMSdevdist = values(3); MeanDevXY = values(4:5); else % Right eye RMSdev(2,:) = values(1:2); RMSdevdist(2,:) = values(3); MeanDevXY(2,:) = values(4:5); end readyonce = 1; % Various commands we don't care about elseif strcmp(command,'ET_REC') || ... strcmp(command,'ET_CLR') || ... strcmp(command,'ET_CAL') || ... strcmp(command,'ET_CSZ') || ... strcmp(command,'ET_ACC') || ... strcmp(command,'ET_CPA') || ... strcmp(command,'ET_FIN') || ... strcmp(command,'ET_LEV') continue % Catch all else fprintf(sprintf(['Validation failed - received unrecognised '... 'input: %s\n'],response)); fprintf(ET_serial,'ET_BRK'); break % DEBUG end % Resp interpretation end % Resp check end % While % Clear the target texture from memory Screen('Close',targetbuf); % Return warning state to whatever it started as warning(wstate.state,wstate.identifier);