# gregfreeman/matlabPyrTools

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 % IM = mkSquare(SIZE, PERIOD, DIRECTION, AMPLITUDE, PHASE, ORIGIN, TWIDTH) % or % IM = mkSine(SIZE, FREQ, AMPLITUDE, PHASE, ORIGIN, TWIDTH) % % Compute a matrix of dimension SIZE (a [Y X] 2-vector, or a scalar) % containing samples of a 2D square wave, with given PERIOD (in % pixels), DIRECTION (radians, CW from X-axis, default = 0), AMPLITUDE % (default = 1), and PHASE (radians, relative to ORIGIN, default = 0). % ORIGIN defaults to the center of the image. TWIDTH specifies width % of raised-cosine edges on the bars of the grating (default = % min(2,period/3)). % % In the second form, FREQ is a 2-vector of frequencies (radians/pixel). % Eero Simoncelli, 6/96. % TODO: Add duty cycle. function [res] = mkSquare(sz, per_freq, dir_amp, amp_phase, phase_orig, orig_twidth, twidth) %------------------------------------------------------------ %% OPTIONAL ARGS: if (prod(size(per_freq)) == 2) frequency = norm(per_freq); direction = atan2(per_freq(1),per_freq(2)); if (exist('dir_amp') == 1) amplitude = dir_amp; else amplitude = 1; end if (exist('amp_phase') == 1) phase = amp_phase; else phase = 0; end if (exist('phase_orig') == 1) origin = phase_orig; end if (exist('orig_twidth') == 1) transition = orig_twidth; else transition = min(2,2*pi/(3*frequency)); end if (exist('twidth') == 1) error('Too many arguments for (second form) of mkSine'); end else frequency = 2*pi/per_freq; if (exist('dir_amp') == 1) direction = dir_amp; else direction = 0; end if (exist('amp_phase') == 1) amplitude = amp_phase; else amplitude = 1; end if (exist('phase_orig') == 1) phase = phase_orig; else phase = 0; end if (exist('orig_twidth') == 1) origin = orig_twidth; end if (exist('twidth') == 1) transition = twidth; else transition = min(2,2*pi/(3*frequency)); end end %------------------------------------------------------------ if (exist('origin') == 1) res = mkRamp(sz, direction, frequency, phase, origin) - pi/2; else res = mkRamp(sz, direction, frequency, phase) - pi/2; end [Xtbl,Ytbl] = rcosFn(transition*frequency,pi/2,[-amplitude amplitude]); res = pointOp(abs(mod(res+pi, 2*pi)-pi),Ytbl,Xtbl(1),Xtbl(2)-Xtbl(1),0); % OLD threshold version: %res = amplitude * (mod(res,2*pi) < pi);