def gen_images(locs, features, n_gridpoints, normalize=True,
augment=False, pca=False, std_mult=0.1, n_components=2, edgeless=False):
"""
Generates EEG images given electrode locations in 2D space and multiple feature values for each electrode
:param locs: An array with shape [n_electrodes, 2] containing X, Y
coordinates for each electrode.
:param features: Feature matrix as [n_samples, n_features]
Features are as columns.
Features corresponding to each frequency band are concatenated.
(alpha1, alpha2, ..., beta1, beta2,...)
:param n_gridpoints: Number of pixels in the output images
:param normalize: Flag for whether to normalize each band over all samples
:param augment: Flag for generating augmented images
:param pca: Flag for PCA based data augmentation
:param std_mult Multiplier for std of added noise
:param n_components: Number of components in PCA to retain for augmentation
:param edgeless: If True generates edgeless images by adding artificial channels
at four corners of the image with value = 0 (default=False).
:return: Tensor of size [samples, colors, W, H] containing generated
images.
"""
feat_array_temp = []
nElectrodes = locs.shape[0] # Number of electrodes
# Test whether the feature vector length is divisible by number of electrodes
assert features.shape[1] % nElectrodes == 0
n_colors = int(features.shape[1] / nElectrodes)
for c in range(n_colors):
feat_array_temp.append(features[:, c * nElectrodes : nElectrodes * (c+1)])
if augment:
if pca:
for c in range(n_colors):
feat_array_temp[c] = augment_EEG(feat_array_temp[c], std_mult, pca=True, n_components=n_components)
else:
for c in range(n_colors):
feat_array_temp[c] = augment_EEG(feat_array_temp[c], std_mult, pca=False, n_components=n_components)
nSamples = features.shape[0]
# Interpolate the values
grid_x, grid_y = np.mgrid[
min(locs[:, 0]):max(locs[:, 0]):n_gridpoints*1j,
min(locs[:, 1]):max(locs[:, 1]):n_gridpoints*1j
]
temp_interp = []
for c in range(n_colors):
temp_interp.append(np.zeros([nSamples, n_gridpoints, n_gridpoints]))
# Generate edgeless images
if edgeless:
min_x, min_y = np.min(locs, axis=0)
max_x, max_y = np.max(locs, axis=0)
locs = np.append(locs, np.array([[min_x, min_y], [min_x, max_y],[max_x, min_y],[max_x, max_y]]),axis=0)
for c in range(n_colors):
feat_array_temp[c] = np.append(feat_array_temp[c], np.zeros((nSamples, 4)), axis=1)
# Interpolating
for i in range(nSamples):
for c in range(n_colors):
temp_interp[c][i, :, :] = griddata(locs, feat_array_temp[c][i, :], (grid_x, grid_y),
method='cubic', fill_value=np.nan)
print('Interpolating {0}/{1}\r'.format(i+1, nSamples), end='\r')
# Normalizing
for c in range(n_colors):
if normalize:
temp_interp[c][~np.isnan(temp_interp[c])] = \
scale(temp_interp[c][~np.isnan(temp_interp[c])])
temp_interp[c] = np.nan_to_num(temp_interp[c])
return np.swapaxes(np.asarray(temp_interp), 0, 1) # swap axes to have [samples, colors, W, H]
def gen_images(locs, features, nGridPoints, normalize=True,
augment=False, pca=False, stdMult=0.1, n_components=2, edgeless=False):
"""
Generates EEG images given electrode locations in 2D space and multiple feature values for each electrode
:param loc: An array with shape [n_electrodes, 2] containing X, Y
coordinates for each electrode.
:param features: Feature matrix as [n_samples, n_features+1]
Features are as columns.
Features corresponding to each frequency band are concatenated.
(alpha1, alpha2, ..., beta1, beta2,...)
:param nGridPoints: Number of pixels in the output images
:param normalize: Flag for whether to normalize each feature over all samples
:param augment: Flag for generating augmented images
:param pca: Flag for PCA based data augmentation
:param stdMult: Standard deviation of noise for augmentation
:param n_components:Number of components in PCA to retain for augmentation
:param edgeless: If True generates edgeless images by adding artificial channels
at four corners of the image with value = 0 (default=False).
:return: Tensor of size [samples, colors, W, H] containing generated
images.
"""
feat_array_temp = []
nElectrodes = locs.shape[0] # Number of electrodes
# Test whether the feature vector length is divisible by number of electrodes (last column is the labels)
assert features.shape[1] % nElectrodes == 0
n_colors = features.shape[1] / nElectrodes
for c in range(n_colors):
feat_array_temp.append(features[:, c * nElectrodes : nElectrodes * (c+1)])
if augment:
if pca:
for c in range(n_colors):
feat_array_temp[c] = augment_EEG(feat_array_temp[c], stdMult, pca=True, n_components=n_components)
else:
for c in range(n_colors):
feat_array_temp[c] = augment_EEG(feat_array_temp[c], stdMult, pca=False, n_components=n_components)
nSamples = features.shape[0]
# Interpolate the values
grid_x, grid_y = np.mgrid[
min(locs[:, 0]):max(locs[:, 0]):nGridPoints*1j,
min(locs[:, 1]):max(locs[:, 1]):nGridPoints*1j
]
temp_interp = []
for c in range(n_colors):
temp_interp.append(np.zeros([nSamples, nGridPoints, nGridPoints]))
# Generate edgeless images
if edgeless:
min_x, min_y = np.min(locs, axis=0)
max_x, max_y = np.max(locs, axis=0)
locs = np.append(locs, np.array([[min_x, min_y], [min_x, max_y],[max_x, min_y],[max_x, max_y]]),axis=0)
for c in range(n_colors):
feat_array_temp[c] = np.append(feat_array_temp[c], np.zeros((nSamples, 4)), axis=1)
for i in xrange(nSamples):
for c in range(n_colors):
temp_interp[c][i, :, :] = griddata(locs, feat_array_temp[c][i, :], (grid_x, grid_y),
method='cubic', fill_value=np.nan)
print 'Interpolating {0}/{1}\r'.format(i+1, nSamples),
for c in range(n_colors):
if normalize:
temp_interp[c][~np.isnan(temp_interp[c])] = \
scale(temp_interp[c][~np.isnan(temp_interp[c])])
temp_interp[c] = np.nan_to_num(temp_interp[c])
return np.swapaxes(np.asarray(temp_interp), 0, 1) # swap axes to have [samples, colors, W, H]
def gen_images(loc_filename, features_filename, nGridPoints,
augment=False, pca=False, stdMult=0.1, n_components=2):
"""
:param loc_filename: Address of the MAT file containing electrode coordinates.
An array with shape [n_electrodes, 2] containing X, Y
coordinates for each electrode.
:param features_filename: Address of the MAT file containing features as columns and
last column as labels.
:param nGridPoints: Number of pixels in the output images
:param augment: Flag for generating augmented images
:param pca: Flag for PCA based data augmentation
:param stdMult: Standard deviation of noise for augmentation
:param n_components:Number of components in PCA to retain for augmentation
:return: Tensor of size [samples, colors, W, H] containing generated
images.
"""
# Load electrode locations projected on a 2D surface
mat = scipy.io.loadmat(loc_filename)
locs = mat['proj'] * [1, -1] # reverse the Y axis to have the front on the top
nElectrodes = locs.shape[0] # Number of electrodes
# Load feature values
mat = scipy.io.loadmat(features_filename)
data = mat['features']
feat_array_temp = []
# Test whether the feature vector length is divisible by number of electrodes (last column is the labels)
assert data.shape[1] % nElectrodes == 1
n_colors = data.shape[1] / nElectrodes
for c in range(n_colors):
feat_array_temp.append(data[:, c * nElectrodes : nElectrodes * (c+1)])
if augment:
if pca:
for c in range(n_colors):
feat_array_temp[c] = augment_EEG(feat_array_temp[c], stdMult, pca=True, n_components=n_components)
else:
for c in range(n_colors):
feat_array_temp[c] = augment_EEG(feat_array_temp[c], stdMult, pca=False, n_components=n_components)
labels = data[:, -1]
nSamples = data.shape[0]
# Interpolate the values
grid_x, grid_y = np.mgrid[
min(locs[:, 0]):max(locs[:, 0]):nGridPoints*1j,
min(locs[:, 1]):max(locs[:, 1]):nGridPoints*1j
]
temp_interp = []
for c in range(n_colors):
temp_interp.append(np.zeros([nSamples, nGridPoints, nGridPoints]))
for i in xrange(nSamples):
for c in range(n_colors):
temp_interp[c][i, :, :] = griddata(locs, feat_array_temp[c][i, :], (grid_x, grid_y),
method='cubic', fill_value=np.nan)
print 'Interpolating {0}/{1}\r'.format(i+1, nSamples),
for c in range(n_colors):
temp_interp[c][~np.isnan(temp_interp[c])] = \
scale(temp_interp[c][~np.isnan(temp_interp[c])])
temp_interp[c] = np.nan_to_num(temp_interp[c])
return np.swapaxes(np.asarray(temp_interp), 0, 1) # swap axes to have [samples, colors, W, H]
)
data = mat['features']
labels = data[:, -1]
nSamples = data.shape[0]
timeFeatMat = []
for winNum in range(numTimeWin):
print 'Processing window {0}/{1}'.format(winNum + 1, numTimeWin)
thetaFeats = data[:, winNum * 192:winNum * 192 + 64]
alphaFeats = data[:, winNum * 192 + 64:winNum * 192 + 128]
betaFeats = data[:, winNum * 192 + 128:winNum * 192 + 192]
if augment:
if pca:
thetaFeats = augment_EEG(thetaFeats,
stdMult,
pca=True,
n_components=n_components)
alphaFeats = augment_EEG(alphaFeats,
stdMult,
pca=True,
n_components=n_components)
betaFeats = augment_EEG(betaFeats,
stdMult,
pca=True,
n_components=n_components)
else:
thetaFeats = augment_EEG(thetaFeats,
stdMult,
pca=False,
n_components=n_components)
alphaFeats = augment_EEG(alphaFeats,
# ax = fig.add_subplot(111)
# ax.scatter(locs[:, 0],locs[:, 1])
# ax.set_xlabel('X'); ax.set_ylabel('Y')
# ax.set_title('Polar Projection')
# pl.ion(); pl.show()
# Load power values
mat = scipy.io.loadmat('Z:\CVPIA\Pouya\SDrive\SkyDrive\Documents\Proposal\Programs\Classifier\Datasets\WM_features_MSP.mat')
data = mat['features']
thetaFeats = data[:, :64]
alphaFeats = data[:, 64:128]
betaFeats = data[:, 128:192]
if augment:
if pca:
thetaFeats = augment_EEG(thetaFeats, stdMult, pca=True, n_components=n_components)
alphaFeats = augment_EEG(alphaFeats, stdMult, pca=True, n_components=n_components)
betaFeats = augment_EEG(betaFeats, stdMult, pca=True, n_components=n_components)
else:
thetaFeats = augment_EEG(thetaFeats, stdMult, pca=False, n_components=n_components)
alphaFeats = augment_EEG(alphaFeats, stdMult, pca=False, n_components=n_components)
betaFeats = augment_EEG(betaFeats, stdMult, pca=False, n_components=n_components)
labels = data[:, -1]
nSamples = data.shape[0]
# Interpolate the values
grid_x, grid_y = np.mgrid[
min(locs[:, 0]):max(locs[:, 0]):nGridPoints*1j,
min(locs[:, 1]):max(locs[:, 1]):nGridPoints*1j
]
