Reputation: 1743
I am using PCA to reduce the dimensions of images before comparing them using the Structural Similarity Index. After using PCA, tf.image.ssim throws an error.
I am comparing images here without the use of PCA. This works perfectly -
import numpy as np
import tensorflow as tf
import time
(x_train, y_train), (x_test, y_test) = tf.keras.datasets.mnist.load_data(
path='mnist.npz'
)
start = time.time()
for i in range(1,6000):
x_train_zero = np.expand_dims(x_train[0], axis=2)
x_train_expanded = np.expand_dims(x_train[i], axis=2)
print(tf.image.ssim(x_train_zero, x_train_expanded, 255))
print(time.time()-start)
I have applied PCA here to reduce the dimensions of images, so that SSIM takes lesser time to compare images -
from sklearn.preprocessing import StandardScaler
from sklearn.decomposition import PCA
x_train = x_train.reshape(60000,-1)
scaler = StandardScaler()
X_scaled = scaler.fit_transform(x_train)
pca = PCA()
pca = PCA(n_components = 11)
X_pca = pca.fit_transform(X_scaled).reshape(60000,11,1)
start = time.time()
for i in range(1,6000):
X_pca_zero = np.expand_dims(X_pca[0], axis=2)
X_pca_expanded = np.expand_dims(X_pca[i], axis=2)
print(tf.image.ssim(X_pca_zero, X_pca_expanded, 255))
print(time.time()-start)
This chunk of code throws the error - InvalidArgumentError: Expected 'tf.Tensor(False, shape=(), dtype=bool)' to be true. Summarized data: 11, 1, 1 11
Upvotes: 0
Views: 3341
Reputation: 4313
So, in short, that error happen because in tf.image.ssim
, the inputs X_pca_zero
and X_pca_expanded
size doesn't match filter_size
, if you have filter_size=11
then the X_pca_zero
and X_pca_expanded
must be at least 11x11, example of how you could change your code:
import tensorflow as tf
import time
from sklearn.preprocessing import StandardScaler
from sklearn.decomposition import PCA
(x_train, y_train), (x_test, y_test) = tf.keras.datasets.mnist.load_data(
path='mnist.npz'
)
x_train = x_train.reshape(60000,-1)
scaler = StandardScaler()
X_scaled = scaler.fit_transform(x_train)
pca = PCA()
pca = PCA(n_components = 16) # or 12 -> 3, 4 filter_size=3
X_pca = pca.fit_transform(X_scaled).reshape(60000, 4, 4, 1)
start = time.time()
X_pca_zero = X_pca[0]
for i in range(1,6000):
X_pca_expanded = X_pca[i]
print(tf.image.ssim(X_pca_zero, X_pca_expanded, 255, filter_size=4))
print(time.time()-start)
Upvotes: 3