def fit(self, imgs, xs, densities, masks):
# print '[Arteta_pipeline] Fitting Classifier to data...'
# only take into account pixels in the boxes
xs = xs[masks[:,:,0]]
# Fit the scaler and the kd-tree
logger.info("Scaling channels...")
self.scaler = StandardScaler()
scaled_xs = self.scaler.fit_transform(np.vstack(xs))
logger.info("Building kd-tree...")
self.kdtree = KDTreeTransformer(self.maxDepth)
self.kdtree.fit(scaled_xs)
# Generate histograms
logger.info("Computing histograms...")
histograms = self._compute_histograms(imgs,masks,xs) # map(self._compute_histograms, imgs, masks, xs) #
logger.info("Integrating histograms and extracting samples...")
xs, ys = zip(*map(self._extract_training_data, histograms, densities, masks))
xs = np.vstack(xs)
ys = np.hstack(ys)
logger.info("Fitting the regressor...")
self.regressor.fit(xs, ys)
indices = np.arange(xs.shape[1])
if self.avoid_negative_density:
while np.any(self.regressor.coef_ < 0):
indices = indices[np.flatnonzero(self.regressor.coef_ > 0)]
self.regressor.fit(xs[:, indices], ys)
self.coef_ = np.zeros(xs.shape[1], dtype=np.float_)
self.coef_[indices] = self.regressor.coef_
self.intercept_ = self.regressor.intercept_
return self
class ArtetaPipeline(object):
def __init__(self,
num_training_samples=None,
kernel_size=15,
kernel_type='gaussian',
avoid_negative_density=False,
random_seed=None,
maxDepth = 8):
self.random_seed = random_seed
self.random_state = np.random.RandomState(self.random_seed)
self.num_training_samples = num_training_samples
self.kernel_size = kernel_size
self.kernel_type = kernel_type
self.avoid_negative_density = avoid_negative_density
self.regressor = linear_model.RidgeCV(
alphas=[100000.0, 10000.0, 1000.0, 100, 10, 1, 0.1, 0.01, 0.001, 0.0001, 1e-05, 1e-06],
cv=None, fit_intercept=False, gcv_mode=None, normalize=False,
scoring=None, store_cv_values=True)
self.maxDepth = maxDepth
# useless function, channels computed by features extractor
def _compute_channels(self, img, density, mask):
phi = self.fextractor.transform_one(img)
xs = phi[mask]
ys = density[mask]
return xs, ys
def _compute_histograms(self, img, mask, x=None):
scaled_x = self.scaler.transform(x)
leaves_x = self.kdtree.transform(scaled_x)
num_leaves = self.kdtree.get_output_ndims()
aux = leaves_x
res = np.zeros(mask.shape + (num_leaves,), dtype=np.float32)
# count = np.sum(leaves_x[:])
# print 'Num leaves : ', num_leaves
# print 'Scaled_x : ', scaled_x.shape
# print 'leaves_x : ', leaves_x.shape
# print 'Sum over scaled x ', count
# print 'shape res : ', res.shape
# print 'mask shape : ', mask.shape
# print 'res[mask] : ', res[mask].shape
res[mask] = aux
return res
def _extract_training_data(self, img, density, mask):
coords = sampling.random_coords_from_mask(self.num_training_samples, mask, self.random_state)
xs, ys = [], []
for size in [self.kernel_size]:
if self.kernel_type == 'flat':
kernel = np.ones(size)
int_img = utils.separate_convolve(img, kernel, axis=[0, 1, 2])
int_density = utils.separate_convolve(density, kernel, axis=[0, 1, 2])
elif self.kernel_type == 'gaussian':
int_img = ndimage.gaussian_filter(img, sigma=[size, size, 0]) #size, # removed on dimension here to work on 2d images first
int_density = ndimage.gaussian_filter(density, sigma=[size, size]) #, size
else:
raise ValueError, "Unknown kernel_type '%s'" % self.kernel_type
xs.append(int_img[coords])
ys.append(int_density[coords])
return np.vstack(xs), np.hstack(ys)
def set_params(self, **args):
# FIXME : mechanism to deal with missing or unexisting inputs
self.maxDepth = args['maxDepth']
self.kernel_size = args['sigma']
def fit(self, imgs, xs, densities, masks):
# print '[Arteta_pipeline] Fitting Classifier to data...'
# only take into account pixels in the boxes
xs = xs[masks[:,:,0]]
# Fit the scaler and the kd-tree
logger.info("Scaling channels...")
self.scaler = StandardScaler()
scaled_xs = self.scaler.fit_transform(np.vstack(xs))
logger.info("Building kd-tree...")
self.kdtree = KDTreeTransformer(self.maxDepth)
self.kdtree.fit(scaled_xs)
# Generate histograms
logger.info("Computing histograms...")
histograms = self._compute_histograms(imgs,masks,xs) # map(self._compute_histograms, imgs, masks, xs) #
logger.info("Integrating histograms and extracting samples...")
xs, ys = zip(*map(self._extract_training_data, histograms, densities, masks))
xs = np.vstack(xs)
ys = np.hstack(ys)
logger.info("Fitting the regressor...")
self.regressor.fit(xs, ys)
indices = np.arange(xs.shape[1])
if self.avoid_negative_density:
while np.any(self.regressor.coef_ < 0):
indices = indices[np.flatnonzero(self.regressor.coef_ > 0)]
self.regressor.fit(xs[:, indices], ys)
self.coef_ = np.zeros(xs.shape[1], dtype=np.float_)
self.coef_[indices] = self.regressor.coef_
self.intercept_ = self.regressor.intercept_
return self
def predict_one(self, img, mask):
logger.info("Computing histograms...")
histograms = self._compute_histograms(None, mask,np.vstack(img))
logger.info("Predicting densities...")
pred = np.dot(histograms[mask], self.coef_) + self.intercept_
res = np.zeros(img.shape[:-1], dtype=np.float32)
res[mask[:,:,0]] = pred
# print 'Results shape : ', res.shape
# print '[Arteta_pipeline] - Predict one - Sum of predictions is : ', np.sum(res[...])
return res
def predict(self, imgs, masks):
# print 'predicting for : ', imgs.shape, masks.shape
return map(self.predict_one, imgs, masks)
def get_params(self):
return {#"feature_extractor": self.fextractor,
"regressor": self.regressor,
"num_training_samples": self.num_training_samples,
"kernel_size": self.kernel_size,
"kernel_type": self.kernel_type,
"random_seed": self.random_seed,
"avoid_negative_density": self.avoid_negative_density}
