# Image Classification for watermarks with poor results

Just starting learning things about tensorflow and NN. As an exercise I decided to create a dataset of images, watermarked and not, in order to binary classify these. First of all, the dataset ( you can see it here ) was created artificially by me applying some random watermarks. First doubt, in the dataset I don't have both images one watermarked and one not, would be better to have? Second, frustrating: model stand on 0.5 accuracy, so it just produce random output :( Model I tried is this:

model = tf.keras.Sequential([
tf.keras.layers.Conv2D(16,(1,1), activation='relu', input_shape=(150, 150, 3)),
tf.keras.layers.MaxPool2D(2,2),
tf.keras.layers.Conv2D(32,(3,3), activation='relu'),
tf.keras.layers.MaxPool2D(2,2),
tf.keras.layers.Conv2D(64,(3,3), activation='relu'),
tf.keras.layers.MaxPool2D(2,2),
tf.keras.layers.Flatten(),
tf.keras.layers.Dense(128, activation='elu'),
tf.keras.layers.Dense(64, activation='elu'),
tf.keras.layers.Dense(32, activation='relu'),
tf.keras.layers.Dense(1,activation="sigmoid")


and then compiled as this:

model.compile(optimizer='adam',
loss='binary_crossentropy',
metrics = ['accuracy'])


Here below the fit:

history = model.fit(train_data,
validation_data=valid_data,
steps_per_epoch=100,
epochs=15,
validation_steps=50,
verbose=2)


As for any other details, code is here. I already checked for technical issues, I'm pretty sure image enter properly, train and validation dataset are 80/20, about 12K images for training. However accuracy bounches up and down around .5 while fitting. How can I improve?

tf.keras.layers.Dense(64, activation='relu'),