annotate constant-q-cpp/misc/yeti/cqt.yeti @ 372:af71cbdab621 tip

Update bqvec code

/*
    Constant-Q library
    Copyright (c) 2013-2014 Queen Mary, University of London

    Permission is hereby granted, free of charge, to any person
    obtaining a copy of this software and associated documentation
    files (the "Software"), to deal in the Software without
    restriction, including without limitation the rights to use, copy,
    modify, merge, publish, distribute, sublicense, and/or sell copies
    of the Software, and to permit persons to whom the Software is
    furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be
    included in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
    NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
    CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
    CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
    WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

    Except as contained in this notice, the names of the Centre for
    Digital Music; Queen Mary, University of London; and Chris Cannam
    shall not be used in advertising or otherwise to promote the sale,
    use or other dealings in this Software without prior written
    authorization.
*/

module cqt;

cqtkernel = load cqtkernel;
resample = load may.stream.resample;
manipulate = load may.stream.manipulate;
mat = load may.matrix;
cm = load may.matrix.complex;
framer = load may.stream.framer;
cplx = load may.complex;
fft = load may.transform.fft;
vec = load may.vector;
ch = load may.stream.channels;

{ pow, round, floor, ceil, log2, nextPowerOfTwo } = load may.mathmisc;

cqt { maxFreq, minFreq, binsPerOctave } str =
   (sampleRate = str.sampleRate;
    octaves = ceil (log2 (maxFreq / minFreq));
//    actualMinFreq = (maxFreq / (pow 2 octaves)) * (pow 2 (1/binsPerOctave));

    kdata = cqtkernel.makeKernel { sampleRate, maxFreq, binsPerOctave };

//    eprintln "sampleRate = \(sampleRate), maxFreq = \(maxFreq), minFreq = \(minFreq), actualMinFreq = \(actualMinFreq), octaves = \(octaves), binsPerOctave = \(binsPerOctave), fftSize = \(kdata.fftSize), hop = \(kdata.fftHop)";

//    eprintln "atomsPerFrame = \(kdata.atomsPerFrame)";

    padding = (kdata.fftSize * (pow 2 (octaves-1)));

//    eprintln "padding = \(padding)";

    str = manipulate.paddedBy padding str;

    streams = manipulate.duplicated octaves str;

    // forward transform uses the conjugate-transposed kernel, inverse
    // uses the original
    kernel = cm.transposed (cm.conjugateTransposed kdata.kernel);

//    eprintln "have kernel";

    fftFunc = fft.forward kdata.fftSize;

    cqblocks =
        map do octave:
            frames = map ch.mixedDown //!!! mono for now
               (framer.frames kdata.fftSize [ Hop kdata.fftHop, Padded false ]
                   (resample.decimated (pow 2 octave) streams[octave]));
            map do frame:
                freq = fftFunc (cplx.complexArray frame (vec.zeros kdata.fftSize));
// eprintln "octave = \(octave), frame = \(vec.list frame)";
// eprintln "octave = \(octave), freq = \(freq)";
                cm.product kernel (cm.newComplexColumnVector freq);
            done frames;
        done [0..octaves-1];

    // The cqblocks list is a list<list<matrix>>. Each top-level list
    // corresponds to an octave, from highest to lowest, each having
    // twice as many elements in its list as the next octave. The
    // sub-lists are sampled in time with an effective spacing of
    // fftSize * 2^(octave-1) audio frames, and the matrices are row
    // vectors with atomsPerFrame * binsPerOctave complex elements.
    //
    // ***
    // 
    // In a typical constant-Q structure, each (2^(octaves-1) *
    // fftHop) input frames gives us an output structure conceptually
    // like this:
    //
    // [][][][][][][][]   <- fftHop frames per highest-octave output value
    // [][][][][][][][]      layered as many times as binsPerOctave (here 2)
    // [--][--][--][--]   <- fftHop*2 frames for the next lower octave
    // [--][--][--][--]      etc
    // [------][------]
    // [------][------]
    // [--------------]
    // [--------------]
    //
    // ***
    //
    // But the kernel we're using here has more than one temporally
    // spaced atom; each individual cell is a row vector with
    // atomsPerFrame * binsPerOctave elements, but that actually
    // represents a rectangular matrix of result cells with width
    // atomsPerFrame and height binsPerOctave. The columns of this
    // matrix (the atoms) then need to be spaced by 2^(octave-1)
    // relative to those from the highest octave.

    // Reshape each row vector into the appropriate rectangular matrix
    // and split into single-atom columns

    emptyHops = kdata.firstCentre / kdata.atomSpacing; //!!! int? round?
//    maxDrop = emptyHops * (pow 2 (octaves-1)) - emptyHops;
//    eprintln "maxDrop = \(maxDrop)";

    cqblocks =
        map do octlist:
            concatMap do rv:
                cm.asColumns
                   (cm.generate do row col:
                        cm.at rv ((row * kdata.atomsPerFrame) + col) 0
                    done {
                        rows = kdata.binsPerOctave,
                        columns = kdata.atomsPerFrame
                    })
            done octlist
        done cqblocks;

    cqblocks = array (map2 do octlist octave:
        d = emptyHops * (pow 2 (octaves-octave)) - emptyHops;
//        eprintln "dropping \(d)";
        drop d octlist;
    done cqblocks [1..octaves]);

    assembleBlock bits =
       (//eprintln "assembleBlock: structure of bits is:";
        //eprintln (map length bits);

        rows = octaves * kdata.binsPerOctave;
        columns = (pow 2 (octaves - 1)) * kdata.atomsPerFrame;

        cm.generate do row col:

            // bits structure: [1,2,4,8,...]

            // each elt of bits is a list of the chunks that should
            // make up this block in that octave (lowest octave first)

            // each chunk has atomsPerFrame * binsPerOctave elts in it

            // row is disposed with 0 at the top, highest octave (in
            // both pitch and index into bits structure)

            oct = int (row / binsPerOctave);
            binNo = row % kdata.binsPerOctave;

            chunks = pow 2 oct;
            colsPerAtom = int (columns / (chunks * kdata.atomsPerFrame));
            atomNo = int (col / colsPerAtom);
            atomOffset = col % colsPerAtom;

            if atomOffset == 0 and atomNo < length bits[oct] then
                bits[oct][atomNo][binNo];
            else
                cplx.zero
            fi;

        done { rows, columns };
        );

    assembleBlockSpectrogram bits =
       (// As assembleBlock, but producing a dense magnitude
        // spectrogram (rather than a complex output). (todo:
        // interpolation, smoothing)

        //eprintln "assembleBlockSpectrogram: structure of bits is:";
        //eprintln (map length bits);

        rows = octaves * kdata.binsPerOctave;
        columns = (pow 2 (octaves - 1)) * kdata.atomsPerFrame;

        mat.generate do row col:

            oct = int (row / binsPerOctave);
            binNo = row % kdata.binsPerOctave;

            chunks = pow 2 oct;
            colsPerAtom = int (columns / (chunks * kdata.atomsPerFrame));
            atomNo = int (col / colsPerAtom);

            if atomNo < length bits[oct] then
                cplx.magnitude bits[oct][atomNo][binNo];
            else 
                0
            fi;

        done { rows, columns };
        );

    processOctaveLists assembler octs =
        case octs[0] of
        block::rest:
           (toAssemble = array 
               (map do oct:
                    n = kdata.atomsPerFrame * pow 2 oct;
                    if not empty? octs[oct] then
                        forBlock = array (take n octs[oct]);
                        octs[oct] := drop n octs[oct];
                        forBlock
                    else
                        array []
                    fi
                done (keys octs));
            assembler toAssemble :. \(processOctaveLists assembler octs));
         _: []
        esac;

//eprintln "cqblocks has \(length cqblocks) entries";

    octaveLists = [:];

    cqblocks = array cqblocks;
    for [1..octaves] do oct:
        octaveLists[octaves - oct] := cqblocks[oct-1];
    done;
/*
    \() (map2 do octlist octave:
println "oct \(octaves) - \(octave) = \(octaves - octave)";
             octaveLists[octaves - octave] := octlist 
         done cqblocks [1..octaves]);
*/
//eprintln "octaveLists keys are: \(keys octaveLists)";

    {
        kernel = kdata with {
            binFrequencies = array
               (concatMap do octave:
                    map do freq:
                        freq / (pow 2 octave);
                    done (reverse (list kdata.binFrequencies))
                done [0..octaves-1])
        },
        sampleRate,
        octaves,
        get cqComplex () = processOctaveLists assembleBlock octaveLists,
        get cqSpectrogram () = processOctaveLists assembleBlockSpectrogram octaveLists,
    }
    );

{ cqt }