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samer@32
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1 function [X, times, edges] = constq(range,res,hop,window,fs,signal)
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samer@32
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2 % as_constq - Constant Q spectrogram.
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samer@32
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3 %
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samer@32
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4 % as_constq ::
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samer@32
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5 % [[2]] ~ 'frequency range as a two-element array, [low high]',
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samer@32
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6 % real ~ 'resolution in octaves',
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samer@32
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7 % natural | [[2]] ~ 'hop size, either in samples, or as a rational',
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samer@32
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8 % natural | [[2]] ~ 'window size, either in samples, or as a rational',
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samer@32
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9 % real ~ 'sampling frequency',
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samer@32
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10 % [[T]] ~ 'signal of length T'
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samer@32
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11 % ->
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samer@32
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12 % [[L,M]] ~ 'L-by-M array containing L-band spectral envelopes',
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samer@32
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13 % [[1,M]] ~ 'array of nominal sampling time for each frame',
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samer@32
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14 % [[L-1]] ~ 'array of L-1 band edge frequencies'.
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samer@32
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15
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samer@32
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16 parms=h_fparms(fs,hop,window);
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samer@33
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17 [S,times]=powspec(parms,signal);
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samer@32
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18
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samer@32
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19 % 1000 Hz is the reference frequency for edge quantisation
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samer@32
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20 nedges=cqedges(fs,range,res,1000);
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samer@32
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21 X=specbasis(parms.FFTsize*nedges,size(S,1))*S;
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samer@32
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22 edges=fs*nedges;
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samer@32
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23
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