view trunk/matlab/bmm/carfac/SAI_Run.m @ 690:76f749d29b48

Fix memory leak in CARFAC.

Also get rid of most uses of auto, which tend to hurt readability
unless the type name is particularly long, especially when it masks
pointers.

% Copyright 2013, Google, Inc.
% Author: Richard F. Lyon
%
% This Matlab file is part of an implementation of Lyon's cochlear model:
% "Cascade of Asymmetric Resonators with Fast-Acting Compression"
% to supplement Lyon's upcoming book "Human and Machine Hearing"
%
% Licensed under the Apache License, Version 2.0 (the "License");
% you may not use this file except in compliance with the License.
% You may obtain a copy of the License at
%
%     http://www.apache.org/licenses/LICENSE-2.0
%
% Unless required by applicable law or agreed to in writing, software
% distributed under the License is distributed on an "AS IS" BASIS,
% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
% See the License for the specific language governing permissions and
% limitations under the License.

function [frame_rate, num_frames] = SAI_Run(CF, input_waves)
% function [CF, SAI_movie] = SAI_Run(CF, input_waves)
% This function runs the CARFAC and display an SAI movie.

n_ch = CF.n_ch;
[n_samp, n_ears] = size(input_waves);
if n_ears ~= CF.n_ears
  error('bad number of input_waves channels passed to CARFAC_Run')
end
fs = CF.fs;

seglen = round(fs / 30);  % Pick about 30 fps
frame_rate = fs / seglen;
n_segs = ceil(n_samp / seglen);

% Design the SAI parameters.
sai_struct.width = 256;
sai_struct.future_lags = sai_struct.width / 2;
sai_struct.window_width = seglen;
n_triggers = 2;
sai_struct.n_window_pos = n_triggers;
sai_struct.channel_smoothing_scale = 0;


% State stored in sai_struct.
% Make the history buffer.
buffer_width = sai_struct.width + ...
    floor((1 + (n_triggers - 1)/2) * sai_struct.window_width);
sai_struct.nap_buffer = zeros(buffer_width, n_ch);
% The SAI frame is transposed to be image-like.
sai_struct.frame = zeros(n_ch, sai_struct.width);

for seg_num = 1:n_segs
  % seg_range is the range of input sample indices for this segment
  if seg_num == n_segs
    % The last segment may be short of seglen, but do it anyway:
    seg_range = (seglen*(seg_num - 1) + 1):n_samp;
  else
    seg_range = seglen*(seg_num - 1) + (1:seglen);
  end
  % NOTE: seg_naps might have multiple channels.
  [seg_naps, CF] = CARFAC_Run_Segment(CF, input_waves(seg_range, :));

  % Rectify.
  % NOTE: This might not be necessary.
  seg_naps = max(0, seg_naps);  

  if seg_num == n_segs  % pad out the last result
    seg_naps = [seg_naps; zeros(seglen - size(seg_naps,1), size(seg_naps, 2))];
  end
 
  % Shift new data into the buffer.
  n_shift = size(seg_naps, 1);
  sai_struct.nap_buffer = [sai_struct.nap_buffer((1 + n_shift):end,:); seg_naps];

  sai_struct = SAI_StabilizeLayer(sai_struct);
  
  cmap = 1 - gray;  % jet
  figure(10)
  image(32 * sai_struct.frame);
  colormap(cmap);
  colorbar

  drawnow
%  imwrite(32*display_frame, cmap, sprintf('frames/frame%05d.png', seg_num));
end

num_frames = seg_num;

return