Changes to Matlab scripts

match.m

@@ -0,0 +1,10 @@
+function match(audio_file, gyro_rec, gyro_fs)
+    % gyro_fs - Gyro sampling frequency
+
+    % plot_spectrums(gyro_rec, GYRO_FS);
+
+    [audio_samples, audio_fs] = audioread(audio_file);
+    [gyro_timestamps, gyro_samples] = read_samples_file(gyro_rec);
+
+    match_samples(audio_samples, audio_fs, gyro_samples, gyro_fs);
+end

match_samples.m

@@ -0,0 +1,11 @@
+function match_samples(audio_samples, audio_fs, gyro_samples, gyro_fs)
+    display(length(gyro_samples));
+
+    display(audio_fs);
+    display(length(audio_samples));
+
+    audio_resampled = resample(audio_samples, gyro_fs, audio_fs);
+    display(length(audio_resampled));
+
+    plot( conv(gyro_samples(:,1), fliplr(audio_resampled)) );
+end

merge_samples.m

@@ -1,28 +1,8 @@
-function [merged_timestamps, merged_signal] = merge_samples(timestamps1, samples1, timestamps2, samples2)
-    merged_timestamps = sort([timestamps1; timestamps2]);
-    merged_signal = zeros(length(timestamps1) + length(timestamps2), size(samples1, 2));
+function [merged_timestamps, merged_signal] = ...
+    merge_samples(timestamps1, samples1, timestamps2, samples2)
+    % Merge samples given their timestamps
 
-    pos1 = 1;
-    pos2 = 1;
-    for pos = 1:length(merged_timestamps)
-        if pos1 <= length(timestamps1) && pos2 <= length(timestamps2)
-            if timestamps1(pos1) < timestamps2(pos2)
-                merged_signal(pos, :) = samples1(pos1, :);
-                pos1 = pos1 + 1;
-            else
-                merged_signal(pos, :) = samples2(pos2, :);
-                pos2 = pos2 + 1;
-            end;
-        else
-            if pos1 <= length(timestamps1)
-                merged_signal(pos, :) = samples1(pos1, :);
-                pos1 = pos1 + 1;
-            end;
-
-            if pos2 <= length(timestamps2)
-                merged_signal(pos, :) = samples2(pos2, :);
-                pos2 = pos2 + 1;
-            end;
-        end;
-    end;
+    [merged_timestamps, ix] = sort([timestamps1(:); timestamps2(:)]);
+    merged_signal = [samples1(:); samples2(:)];
+    merged_signal = merged_signal(ix);
 end

merge_signals.m

@@ -0,0 +1,8 @@
+function [merged_signals] = merge_signals(sig1, sig2, offset1, offset2, n)
+    % Merge two signals sample-by-sample given the samples and offsets
+
+    timestamps1 = offset1:n:offset1+length(sig1)*n - 1;
+    timestamps2 = offset2:n:offset2+length(sig2)*n - 1;
+    [~, merged_signals] = merge_samples(timestamps1, sig1, ...
+        timestamps2, sig2);
+end

plot_spectrums.m

@@ -1,7 +1,9 @@
 function plot_spectrums(filename, fs)
+    nfft = 256;
     [~, samples] = read_samples_file(filename);
     for k = 1:3
         figure;
-        spectrogram(samples(:, k), 128, 120, fs);
+        % specgram(samples(:, k), 128, 120);
+        spectrogram(samples(:, k), hanning(nfft), round(nfft * 0.9), nfft, fs);
     end;
 end