def test_groupnorm_correctness_2d_different_groups():
norm1 = normalization.GroupNormalization(axis=1,
input_shape=(10, 6),
groups=2)
norm2 = normalization.GroupNormalization(axis=1,
input_shape=(10, 6),
groups=1)
norm3 = normalization.GroupNormalization(axis=1,
input_shape=(10, 6),
groups=10)
model = Sequential()
model.add(norm1)
model.compile(loss='mse', optimizer='rmsprop')
# centered on 5.0, variance 10.0
x = np.random.normal(loc=5.0, scale=10.0, size=(1000, 10, 6))
model.fit(x, x, epochs=5, verbose=0)
out = model.predict(x)
out -= np.reshape(K.eval(norm1.beta), (1, 10, 1))
out /= np.reshape(K.eval(norm1.gamma), (1, 10, 1))
assert_allclose(out.mean(axis=(0, 2)), 0.0, atol=1.1e-1)
assert_allclose(out.std(axis=(0, 2)), 1.0, atol=1.1e-1)
model = Sequential()
model.add(norm2)
model.compile(loss='mse', optimizer='rmsprop')
# centered on 5.0, variance 10.0
x = np.random.normal(loc=5.0, scale=10.0, size=(1000, 10, 6))
model.fit(x, x, epochs=5, verbose=0)
out = model.predict(x)
out -= np.reshape(K.eval(norm2.beta), (1, 10, 1))
out /= np.reshape(K.eval(norm2.gamma), (1, 10, 1))
assert_allclose(out.mean(axis=(0, 2)), 0.0, atol=1.1e-1)
assert_allclose(out.std(axis=(0, 2)), 1.0, atol=1.1e-1)
model = Sequential()
model.add(norm3)
model.compile(loss='mse', optimizer='rmsprop')
# centered on 5.0, variance 10.0
x = np.random.normal(loc=5.0, scale=10.0, size=(1000, 10, 6))
model.fit(x, x, epochs=5, verbose=0)
out = model.predict(x)
out -= np.reshape(K.eval(norm3.beta), (1, 10, 1))
out /= np.reshape(K.eval(norm3.gamma), (1, 10, 1))
assert_allclose(out.mean(axis=(0, 2)), 0.0, atol=1.1e-1)
assert_allclose(out.std(axis=(0, 2)), 1.0, atol=1.1e-1)
def test_groupnorm_mode_twice():
# This is a regression test for issue #4881 with the old
# batch normalization functions in the Theano backend.
model = Sequential()
model.add(normalization.GroupNormalization(input_shape=(10, 5, 5),
axis=1,
groups=2))
model.add(normalization.GroupNormalization(input_shape=(10, 5, 5),
axis=1,
groups=2))
model.compile(loss='mse', optimizer='sgd')
x = np.random.normal(loc=5.0, scale=10.0, size=(20, 10, 5, 5))
model.fit(x, x, epochs=1, verbose=0)
model.predict(x)
def test_shared_groupnorm():
'''Test that a GN layer can be shared
across different data streams.
'''
# Test single layer reuse
bn = normalization.GroupNormalization(input_shape=(10, ), groups=2)
x1 = Input(shape=(10, ))
bn(x1)
x2 = Input(shape=(10, ))
y2 = bn(x2)
x = np.random.normal(loc=5.0, scale=10.0, size=(2, 10))
model = Model(x2, y2)
assert len(model.updates) == 0
model.compile('sgd', 'mse')
model.train_on_batch(x, x)
# Test model-level reuse
x3 = Input(shape=(10, ))
y3 = model(x3)
new_model = Model(x3, y3)
assert len(model.updates) == 0
new_model.compile('sgd', 'mse')
new_model.train_on_batch(x, x)
def test_groupnorm_convnet_no_center_no_scale():
model = Sequential()
norm = normalization.GroupNormalization(axis=-1, center=False, scale=False,
input_shape=(3, 4, 4), groups=2)
model.add(norm)
model.compile(loss='mse', optimizer='sgd')
# centered on 5.0, variance 10.0
x = np.random.normal(loc=5.0, scale=10.0, size=(1000, 3, 4, 4))
model.fit(x, x, epochs=4, verbose=0)
out = model.predict(x)
assert_allclose(np.mean(out, axis=(0, 2, 3)), 0.0, atol=1e-1)
assert_allclose(np.std(out, axis=(0, 2, 3)), 1.0, atol=1e-1)
def test_groupnorm_correctness_1d():
model = Sequential()
norm = normalization.GroupNormalization(input_shape=(10, ), groups=2)
model.add(norm)
model.compile(loss='mse', optimizer='rmsprop')
# centered on 5.0, variance 10.0
x = np.random.normal(loc=5.0, scale=10.0, size=(1000, 10))
model.fit(x, x, epochs=5, verbose=0)
out = model.predict(x)
out -= K.eval(norm.beta)
out /= K.eval(norm.gamma)
assert_allclose(out.mean(), 0.0, atol=1e-1)
assert_allclose(out.std(), 1.0, atol=1e-1)
def test_groupnorm_convnet():
model = Sequential()
norm = normalization.GroupNormalization(axis=1,
input_shape=(3, 4, 4),
groups=3)
model.add(norm)
model.compile(loss='mse', optimizer='sgd')
# centered on 5.0, variance 10.0
x = np.random.normal(loc=5.0, scale=10.0, size=(1000, 3, 4, 4))
model.fit(x, x, epochs=4, verbose=0)
out = model.predict(x)
out -= np.reshape(K.eval(norm.beta), (1, 3, 1, 1))
out /= np.reshape(K.eval(norm.gamma), (1, 3, 1, 1))
assert_allclose(np.mean(out, axis=(0, 2, 3)), 0.0, atol=1e-1)
assert_allclose(np.std(out, axis=(0, 2, 3)), 1.0, atol=1e-1)
def test_that_trainable_disables_updates():
val_a = np.random.random((10, 4))
val_out = np.random.random((10, 4))
a = Input(shape=(4, ))
layer = normalization.GroupNormalization(input_shape=(4, ), groups=2)
b = layer(a)
model = Model(a, b)
model.trainable = False
assert len(model.updates) == 0
model.compile('sgd', 'mse')
assert len(model.updates) == 0
x1 = model.predict(val_a)
model.train_on_batch(val_a, val_out)
x2 = model.predict(val_a)
assert_allclose(x1, x2, atol=1e-7)
model.trainable = True
model.compile('sgd', 'mse')
assert len(model.updates) == 0
model.train_on_batch(val_a, val_out)
x2 = model.predict(val_a)
assert np.abs(np.sum(x1 - x2)) > 1e-5
layer.trainable = False
model.compile('sgd', 'mse')
assert len(model.updates) == 0
x1 = model.predict(val_a)
model.train_on_batch(val_a, val_out)
x2 = model.predict(val_a)
assert_allclose(x1, x2, atol=1e-7)