diff trunk/matlab/bmm/carfac/SAI_Run_Segment.m @ 700:597913e855fd

Factor out SAI_Run_Segment, and output test_data for comparison with C++ code.

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/trunk/matlab/bmm/carfac/SAI_Run_Segment.m	Thu Jun 27 22:28:42 2013 +0000
@@ -0,0 +1,53 @@
+% 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 sai_struct = SAI_Run_Segment(sai_struct, input)
+% function sai_frame = SAI_Run_Segment(sai_struct, input)
+% Compute a single SAI frame from the given multichannel input signal.
+
+% Store state used between successive calls to this function in sai_struct.
+if ~isfield(sai_struct, 'nap_buffer')
+  % Make the history buffer.
+  buffer_width = sai_struct.width + ...
+      floor((1 + (sai_struct.n_window_pos - 1)/2) * sai_struct.window_width);
+  n_ch = size(input, 2);
+  sai_struct.nap_buffer = zeros(buffer_width, n_ch);
+end
+if ~isfield(sai_struct, 'frame')
+  % The SAI frame is transposed to be image-like.
+  sai_struct.frame = zeros(n_ch, sai_struct.width);
+end
+
+if size(input, 1) < sai_struct.window_width  % pad out the last result
+  input = [input; ...
+           zeros(sai_struct.window_width - size(input, 1), size(input, 2))];
+end
+size(input)
+sai_struct.window_width
+
+assert(size(input, 1) == sai_struct.window_width)
+
+% Shift new data into the buffer.
+num_shift = size(input, 1);
+sai_struct.nap_buffer = [sai_struct.nap_buffer((1 + num_shift):end,:); ...
+                         input];
+
+sai_struct = SAI_StabilizeLayer(sai_struct);
+  
+return