Initial commitHEADmaster

* codec2 cut-down version 1.2.0
* Remove codebook and generation of sources
* remove c2dec c2enc binaries
* prepare for emscripten

1 files changed, 22 insertions, 0 deletions

diff --git a/octave/plot_specgram.m b/octave/plot_specgram.m
new file mode 100644
index 0000000..7b9e3a6
--- /dev/null
+++ b/octave/plot_specgram.m
@@ -0,0 +1,22 @@
+% plot_specgram.m
+% David Rowe May 2017
+%
+% As the name suggests.....
+
+function S = plot_specgram(x, Fs=8000, fmin, fmax)
+  
+  step = fix(20*Fs/1000);     # one spectral slice every 5 ms
+  window = fix(160*Fs/1000);  # 40 ms data window
+  fftn = 2^nextpow2(window);  # next highest power of 2
+  [S, f, t] = specgram(x, fftn, Fs, window, window-step);
+  S = abs(S(2:fftn/2,:));     # magnitude in range 0<f<=Fs/2 Hz.
+  S = S/max(S(:));            # normalize magnitude so that max is 0 dB.
+  S = max(S, 10^(-20/10));    # clip below -20 dB.
+  S = min(S, 10^(-3/10));     # clip above -3 dB.
+  imagesc (t, f, log(S));     # display in log scale
+  set (gca, "ydir", "normal"); # put the 'y' direction in the correct direction
+  if nargin > 2
+    axis([0 max(t) fmin fmax])
+  end
+  xlabel('Time (s)'); ylabel('Freq (Hz)');
+endfunction