Ejemplo n.º 1
0
    def __init__(self, D0, lmbda=None, opt=None, dimK=None, dimN=2):
        """
        Parameters
        ----------
        D0 : array_like
          Initial dictionary array
        lmbda : float
          Regularisation parameter
        opt : :class:`OnlineConvBPDNDictLearn.Options` object
          Algorithm options
        dimK : 0, 1, or None, optional (default None)
          Number of signal dimensions in signal array passed to
          :meth:`solve`. If there will only be a single input signal
          (e.g. if `S` is a 2D array representing a single image)
          `dimK` must be set to 0.
        dimN : int, optional (default 2)
          Number of spatial/temporal dimensions
        """

        if opt is None:
            opt = OnlineConvBPDNDictLearn.Options()
        if not isinstance(opt, OnlineConvBPDNDictLearn.Options):
            raise TypeError('Parameter opt must be an instance of '
                            'OnlineConvBPDNDictLearn.Options')
        self.opt = opt

        if dimN != 2 and opt['CUDA_CBPDN']:
            raise ValueError('CUDA CBPDN solver can only be used when dimN=2')

        if opt['CUDA_CBPDN'] and cuda.device_count() == 0:
            raise ValueError('SPORCO-CUDA not installed or no GPU available')

        self.dimK = dimK
        self.dimN = dimN

        # DataType option overrides data type inferred from __init__
        # parameters of derived class
        self.set_dtype(opt, D0.dtype)

        # Initialise attributes representing algorithm parameter
        self.lmbda = lmbda
        self.eta_a = opt['eta_a']
        self.eta_b = opt['eta_b']
        self.set_attr('eta',
                      opt['eta_a'] / opt['eta_b'],
                      dval=2.0,
                      dtype=self.dtype)

        # Get dictionary size
        if self.opt['DictSize'] is None:
            self.dsz = D0.shape
        else:
            self.dsz = self.opt['DictSize']

        # Construct object representing problem dimensions
        self.cri = None

        # Normalise dictionary
        ds = cr.DictionarySize(self.dsz, dimN)
        dimCd = ds.ndim - dimN - 1
        D0 = cr.stdformD(D0, ds.nchn, ds.nflt, dimN).astype(self.dtype)
        self.D = cr.Pcn(D0,
                        self.dsz, (),
                        dimN,
                        dimCd,
                        crp=True,
                        zm=opt['ZeroMean'])
        self.Dprv = self.D.copy()

        # Create constraint set projection function
        self.Pcn = cr.getPcn(self.dsz, (),
                             dimN,
                             dimCd,
                             crp=True,
                             zm=opt['ZeroMean'])

        # Initalise iterations stats list and iteration index
        self.itstat = []
        self.j = 0

        # Configure status display
        self.display_config()
Ejemplo n.º 2
0
    def __init__(self, dsz, S, dimK=None, dimN=2):
        """Initialise a ConvRepIndexing object.

        Initialise a ConvRepIndexing object representing dimensions
        of S (input signal), D (dictionary), and X (coefficient array)
        in a convolutional representation. These dimensions are inferred
        from the input `dsz` and `S` as well as from parameters `dimN`
        and `dimK`. Management and inferrence of these problem
        dimensions is not entirely straightforward because
        :class:`.ConvCnstrMODBase` and related classes make use
        *internally* of S, D, and X arrays with a standard layout
        (described below), but *input* `S` and `dsz` are allowed to
        deviate from this layout for the convenience of the user. Note
        that S, D, and X refers to the names of signal, dictionary, and
        coefficient map arrays in :class:`.admm.cbpdn.ConvBPDN`; the
        corresponding variable names in :class:`.ConvCnstrMODBase` are
        S, X, and Z.

        The most fundamental parameter is `dimN`, which specifies the
        dimensionality of the spatial/temporal samples being represented
        (e.g. `dimN` = 2 for representations of 2D images). This should
        be common to *input* `S` and `dsz`, and is also common to
        *internal* S, D, and X. The remaining dimensions of input `S`
        can correspond to multiple channels (e.g. for RGB images) and/or
        multiple signals (e.g. the array contains multiple independent
        images). If input `S` contains two additional dimensions (in
        addition to the `dimN` spatial dimensions), then those are
        considered to correspond, in order, to channel and signal
        indices. If there is only a single additional dimension, then
        determination whether it represents a channel or signal index is
        more complicated. The rule for making this determination is as
        follows:

        * if `dimK` is set to 0 or 1 instead of the default ``None``,
          then that value is taken as the number of signal indices in
          input `S` and any remaining indices are taken as channel
          indices (i.e. if `dimK` = 0 then dimC = 1 and if `dimK` = 1
          then dimC = 0).
        * if `dimK` is ``None`` then the number of channel dimensions
          is determined from the number of dimensions specified in the
          input dictionary size `dsz`. Input `dsz` should specify at
          least `dimN` + 1 dimensions, with the final dimension
          indexing dictionary filters. If it has exactly `dimN` + 1
          dimensions then it is a single-channel dictionary, and input
          `S` is also assumed to be single-channel, with the
          additional index in `S` assigned as a signal index
          (i.e. `dimK` = 1).  Conversely, if input `dsz` specified
          `dimN` + 2 dimensions it is a multi-channel dictionary, and
          the additional index in `S` is assigned as a channel index
          (i.e. dimC = 1).

        Note that it is an error to specify `dimK` = 1 if input `S`
        has `dimN` + 1 dimensions and input `dsz` specified `dimN` + 2
        dimensions since a multi-channel dictionary requires a
        multi-channel signal. (The converse is not true: a
        multi-channel signal can be decomposed using a single-channel
        dictionary.)

        The *internal* data layout for S (signal), D (dictionary), and
        X (coefficient array) is (multi-channel dictionary)
        ::

            sptl.          chn  sig  flt
          S(N0,  N1, ...,  C,   K,   1)
          D(N0,  N1, ...,  C,   1,   M)
          X(N0,  N1, ...,  C,   K,   M)

        or (single-channel dictionary)

        ::

            sptl.          chn  sig  flt
          S(N0,  N1, ...,  C,   K,   1)
          D(N0,  N1, ...,  1,   1,   M)
          X(N0,  N1, ...,  C,   K,   M)

        where

        * Nv = [N0, N1, ...] and N = N0 x N1 x ... are the vector of
          sizes of the spatial/temporal indices and the total number of
          spatial/temporal samples respectively
        * C is the number of channels in S
        * K is the number of signals in S
        * M is the number of filters in D

        It should be emphasised that dimC and dimK may take on values
        0 or 1, and represent the number of channel and signal
        dimensions respectively *in input S*. In the internal layout
        of S there is always a dimension allocated for channels and
        signals. The number of channel dimensions in input `D` and the
        corresponding size of that index are represented by dimCd
        and Cd respectively.

        Parameters
        ----------
        dsz : tuple
          Dictionary size specification (using the same format as the
          `dsz` argument of :func:`bcrop`)
        S : array_like
          Input signal
        dimK : 0, 1, or None, optional (default None)
          Number of dimensions in input signal corresponding to multiple
          independent signals
        dimN : int, optional (default 2)
          Number of spatial/temporal dimensions of signal samples
        """

        # Extract properties of dictionary size specification tuple
        ds = cr.DictionarySize(dsz, dimN)
        self.dimCd = ds.ndim - dimN - 1
        self.Cd = ds.nchn
        self.M = ds.nflt
        self.dsz = dsz

        # Numbers of spatial, channel, and signal dimensions in
        # external S are dimN, dimC, and dimK respectively. These need
        # to be calculated since inputs D and S do not already have
        # the standard data layout above, i.e. singleton dimensions
        # will not be present
        if dimK is None:
            rdim = S.ndim - dimN
            if rdim == 0:
                (dimC, dimK) = (0, 0)
            elif rdim == 1:
                dimC = self.dimCd  # Assume S has same number of channels as D
                dimK = S.ndim - dimN - dimC  # Assign remaining channels to K
            else:
                (dimC, dimK) = (1, 1)
        else:
            dimC = S.ndim - dimN - dimK  # Assign remaining channels to C

        self.dimN = dimN  # Number of spatial dimensions
        self.dimC = dimC  # Number of channel dimensions in S
        self.dimK = dimK  # Number of signal dimensions in S

        # Number of channels in S
        if self.dimC == 1:
            self.C = S.shape[dimN]
        else:
            self.C = 1
        self.Cx = self.C

        # Ensure that multi-channel dictionaries used with a signal with a
        # matching number of channels
        if self.Cd > 1 and self.C != self.Cd:
            raise ValueError("Multi-channel dictionary with signal with "
                             "mismatched number of channels (Cd=%d, C=%d)" %
                             (self.Cd, self.C))

        # Number of signals in S
        if self.dimK == 1:
            self.K = S.shape[self.dimN + self.dimC]
        else:
            self.K = 1

        # Shape of spatial indices and number of spatial samples
        self.Nv = S.shape[0:dimN]
        self.N = np.prod(np.array(self.Nv))

        # Axis indices for each component of X and internal S and D
        self.axisN = tuple(range(0, dimN))
        self.axisC = dimN
        self.axisK = dimN + 1
        self.axisM = dimN + 2

        # Shapes of internal S, D, and X
        self.shpD = self.Nv + (self.Cd, ) + (1, ) + (self.M, )
        self.shpS = self.Nv + (self.C, ) + (self.K, ) + (1, )
        self.shpX = self.Nv + (self.Cx, ) + (self.K, ) + (self.M, )
Ejemplo n.º 3
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 def test_06(self):
     dsz = ((8, 8, 3, 16), (12, 12, 3, 32))
     ds = cnvrep.DictionarySize(dsz)
     assert ds.nchn == 3
     assert ds.nflt == 48
Ejemplo n.º 4
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 def test_07(self):
     dsz = (((5, 5, 2, 8), (7, 7, 1, 8)), ((9, 9, 2, 16), (10, 10, 1, 16)))
     ds = cnvrep.DictionarySize(dsz)
     assert ds.nchn == 3
     assert ds.nflt == 24
Ejemplo n.º 5
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 def test_04(self):
     dsz = (8, 8, 32)
     ds = cnvrep.DictionarySize(dsz)
     assert ds.nchn == 1
     assert ds.nflt == 32
     assert str(ds) != ''