In [1]:
import nengo
import numpy as np
import cPickle
from nengo_extras.data import load_mnist
from nengo_extras.vision import Gabor, Mask
from matplotlib import pylab
import matplotlib.pyplot as plt
import matplotlib.animation as animation
import scipy.ndimage
from skimage.measure import compare_ssim as ssim
Load the MNIST database
In [2]:
# --- load the data
img_rows, img_cols = 28, 28
(X_train, y_train), (X_test, y_test) = load_mnist()
X_train = 2 * X_train - 1 # normalize to -1 to 1
X_test = 2 * X_test - 1 # normalize to -1 to 1
Each digit is represented by a one hot vector where the index of the 1 represents the number
In [3]:
temp = np.diag([1]*10)
ZERO = temp[0]
ONE = temp[1]
TWO = temp[2]
THREE= temp[3]
FOUR = temp[4]
FIVE = temp[5]
SIX = temp[6]
SEVEN =temp[7]
EIGHT= temp[8]
NINE = temp[9]
labels =[ZERO,ONE,TWO,THREE,FOUR,FIVE,SIX,SEVEN,EIGHT,NINE]
dim =28
Load the saved weight matrices that were created by training the model
In [4]:
label_weights = cPickle.load(open("label_weights5000.p", "rb"))
activity_to_img_weights = cPickle.load(open("activity_to_img_weights5000.p", "rb"))
rotated_clockwise_after_encoder_weights = cPickle.load(open("rotated_after_encoder_weights_clockwise5000.p", "r"))
rotated_counter_after_encoder_weights = cPickle.load(open("rotated_after_encoder_weights5000.p", "r"))
#identity_after_encoder_weights = cPickle.load(open("identity_after_encoder_weights1000.p","r"))
#rotation_clockwise_weights = cPickle.load(open("rotation_clockwise_weights1000.p","rb"))
#rotation_counter_weights = cPickle.load(open("rotation_weights1000.p","rb"))
In [5]:
#Training with filters used on train images
#low_pass_weights = cPickle.load(open("low_pass_weights1000.p", "rb"))
#rotated_counter_after_encoder_weights_noise = cPickle.load(open("rotated_after_encoder_weights_counter_filter_noise5000.p", "r"))
#rotated_counter_after_encoder_weights_filter = cPickle.load(open("rotated_after_encoder_weights_counter_filter5000.p", "r"))
Functions to perform the inhibition of each ensemble
In [6]:
#A value of zero gives no inhibition
def inhibit_rotate_clockwise(t):
if t < 0.5:
return dim**2
else:
return 0
def inhibit_rotate_counter(t):
if t < 0.5:
return 0
else:
return dim**2
def inhibit_identity(t):
if t < 0.3:
return dim**2
else:
return dim**2
In [7]:
def intense(img):
newImg = img.copy()
newImg[newImg < 0] = -1
newImg[newImg > 0] = 1
return newImg
def node_func(t,x):
#clean = scipy.ndimage.gaussian_filter(x, sigma=1)
#clean = scipy.ndimage.median_filter(x, 3)
clean = intense(x)
return clean
In [8]:
#Create stimulus at horizontal
weight = np.dot(label_weights,activity_to_img_weights)
img = np.dot(THREE,weight)
plt.subplot(121)
pylab.imshow(img.reshape(28,28),cmap="gray")
#img =X_train[7]
rot_img =scipy.ndimage.interpolation.rotate(img.reshape(28,28),40,reshape=False,cval=-1).ravel()
pylab.imshow(rot_img.reshape(28,28),cmap='gray')
plt.show()
In [9]:
def ssim_func(x):
img1 = np.dot(x[:5000],activity_to_img_weights)
img2 = np.dot(x[5000:],activity_to_img_weights)
return ssim(img1.reshape(28,28),img2.reshape(28,28))
def activity_sim_func(x):
u=x[:5000]
v=x[5000:]
#a= nengo.spa.similarity(u,v,normalize=True)
a = np.dot(u,v)
return a
In [10]:
rng = np.random.RandomState(9)
n_hid = 5000
model = nengo.Network(seed=3)
with model:
#Stimulus to be matched to
static_stim = nengo.Node(img)
#Stimulus only shows for brief period of time
rot_stim = nengo.Node(lambda t: rot_img if t < 0.1 else 0)
ens_params = dict(
eval_points=X_train,
neuron_type=nengo.LIF(),
intercepts=nengo.dists.Choice([-0.5]),
max_rates=nengo.dists.Choice([100]),
)
# linear filter used for edge detection as encoders, more plausible for human visual system
encoders = Gabor().generate(n_hid, (11, 11), rng=rng)
encoders = Mask((28, 28)).populate(encoders, rng=rng, flatten=True)
#Ensemble that represents the image to be matched
static_ens = nengo.Ensemble(n_neurons=5000, dimensions=784,seed=3, encoders=encoders, **ens_params) #Direct? cannot because similarity between activities
nengo.Connection(static_stim, static_ens)
#Ensemble that represents the image and will be rotated
ens = nengo.Ensemble(n_hid, dim**2, seed=3, encoders=encoders, **ens_params)
#Connect stimulus to ensemble, transform using learned weight matrices
nengo.Connection(rot_stim, ens)
#Recurrent connection on the neurons of the ensemble to perform the rotation
nengo.Connection(ens.neurons, ens.neurons, transform = rotated_clockwise_after_encoder_weights.T, synapse=0.1)
#Bring two images together to calculate similarity
#Ideally:
#combine = nengo.Ensemble(10000, 784*2) #Not direct, connections to actual neurons
combine = nengo.Ensemble(1000, 10000, neuron_type=nengo.Direct())
nengo.Connection(static_ens.neurons,combine[:5000])
nengo.Connection(ens.neurons, combine[5000:])
#structural similarity measure
ssim_node = nengo.Node(None, size_in=1)
nengo.Connection(combine, ssim_node, function = ssim_func)
#neural activity similarity measure
activity_sim_node = nengo.Node(None,size_in=1)
nengo.Connection(combine, activity_sim_node, function=activity_sim_func)
#Collect output, use synapse for smoothing
probe = nengo.Probe(ens.neurons,synapse=0.1)
static_probe = nengo.Probe(static_ens.neurons,synapse=0.1)
ssim_probe = nengo.Probe(ssim_node,synapse=0.1)
activity_sim_probe = nengo.Probe(activity_sim_node,synapse=0.1)
In [11]:
sim = nengo.Simulator(model)
In [12]:
sim.run(5)
In [31]:
%matplotlib inline
#Graph of probe output
plt.plot(sim.trange(), sim.data[ssim_probe], 'k', label="SSIM")
plt.legend()
plt.show()
In [13]:
#Graph of probe output
plt.plot(sim.trange(), sim.data[activity_sim_probe], 'k', label="Activity Similarity")
plt.legend()
plt.show()
In [38]:
#Turn probe activity to img
output_acts = []
for act in sim.data[probe]:
output_acts.append(np.dot(act,activity_to_img_weights))
In [83]:
'''Animation for Probe output'''
fig = plt.figure()
def updatefig(i):
im = pylab.imshow(np.reshape(output_acts[i],(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'),animated=True)
return im,
ani = animation.FuncAnimation(fig, updatefig, interval=0.1, blit=True)
plt.show()
In [39]:
#ouput_acts = sim.data[probe]
plt.subplot(261)
plt.title("100")
pylab.imshow(np.reshape(output_acts[100],(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
plt.subplot(262)
plt.title("500")
pylab.imshow(np.reshape(output_acts[500],(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
plt.subplot(263)
plt.title("1000")
pylab.imshow(np.reshape(output_acts[1000],(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
plt.subplot(264)
plt.title("1500")
pylab.imshow(np.reshape(output_acts[1500],(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
plt.subplot(265)
plt.title("2000")
pylab.imshow(np.reshape(output_acts[2000],(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
plt.subplot(266)
plt.title("2500")
pylab.imshow(np.reshape(output_acts[2500],(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
plt.subplot(267)
plt.title("3000")
pylab.imshow(np.reshape(output_acts[3000],(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
plt.subplot(268)
plt.title("3500")
pylab.imshow(np.reshape(output_acts[3500],(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
plt.subplot(269)
plt.title("4000")
pylab.imshow(np.reshape(output_acts[4000],(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
plt.subplot(2,6,10)
plt.title("4500")
pylab.imshow(np.reshape(output_acts[4500],(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
plt.subplot(2,6,11)
plt.title("5000")
pylab.imshow(np.reshape(output_acts[4999],(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
plt.show()
Pickle the probe's output if it takes a long time to run
In [ ]:
#The filename includes the number of neurons and which digit is being rotated
filename = "mental_rotation_output_ONE_" + str(n_hid) + ".p"
cPickle.dump(sim.data[probe], open( filename , "wb" ) )
In [171]:
testing = np.dot(ONE,np.dot(label_weights,activity_to_img_weights))
testing = output_acts[300]
plt.subplot(131)
pylab.imshow(np.reshape(testing,(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
#Get image
#testing = np.dot(ONE,np.dot(label_weights,activity_to_img_weights))
#noise = np.random.random([28,28]).ravel()
testing = node_func(0,testing)
plt.subplot(132)
pylab.imshow(np.reshape(testing,(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
#Get activity of image
_, testing_act = nengo.utils.ensemble.tuning_curves(ens, sim, inputs=testing)
#Get encoder outputs
testing_filter = np.dot(testing_act,rotated_counter_after_encoder_weights_filter)
#Get activities
testing_filter = ens.neuron_type.rates(testing_filter, sim.data[ens].gain, sim.data[ens].bias)
for i in range(5):
testing_filter = np.dot(testing_filter,rotated_counter_after_encoder_weights_filter)
testing_filter = ens.neuron_type.rates(testing_filter, sim.data[ens].gain, sim.data[ens].bias)
testing_filter = np.dot(testing_filter,activity_to_img_weights)
testing_filter = node_func(0,testing_filter)
_, testing_filter = nengo.utils.ensemble.tuning_curves(ens, sim, inputs=testing_filter)
#testing_rotate = np.dot(testing_rotate,rotation_weights)
testing_filter = np.dot(testing_filter,activity_to_img_weights)
plt.subplot(133)
pylab.imshow(np.reshape(testing_filter,(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
plt.show()
In [ ]:
plt.subplot(121)
pylab.imshow(np.reshape(X_train[0],(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
#Get activity of image
_, testing_act = nengo.utils.ensemble.tuning_curves(ens, sim, inputs=X_train[0])
testing_rotate = np.dot(testing_act,activity_to_img_weights)
plt.subplot(122)
pylab.imshow(np.reshape(testing_rotate,(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
plt.show()
In [ ]:
letterO = np.dot(ZERO,np.dot(label_weights,activity_to_img_weights))
plt.subplot(161)
pylab.imshow(np.reshape(letterO,(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
letterL = np.dot(SEVEN,label_weights)
for _ in range(30):
letterL = np.dot(letterL,rotation_weights)
letterL = np.dot(letterL,activity_to_img_weights)
plt.subplot(162)
pylab.imshow(np.reshape(letterL,(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
letterI = np.dot(ONE,np.dot(label_weights,activity_to_img_weights))
plt.subplot(163)
pylab.imshow(np.reshape(letterI,(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
plt.subplot(165)
pylab.imshow(np.reshape(letterI,(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
letterV = np.dot(SEVEN,label_weights)
for _ in range(40):
letterV = np.dot(letterV,rotation_weights)
letterV = np.dot(letterV,activity_to_img_weights)
plt.subplot(164)
pylab.imshow(np.reshape(letterV,(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
letterA = np.dot(SEVEN,label_weights)
for _ in range(10):
letterA = np.dot(letterA,rotation_weights)
letterA = np.dot(letterA,activity_to_img_weights)
plt.subplot(166)
pylab.imshow(np.reshape(letterA,(dim, dim), 'F').T, cmap=plt.get_cmap('Greys_r'))
plt.show()