how to save resized images using ImageDataGenerator and flow_from_directory in keras
Heres a very simple version of saving augmented images of one image wherever you want:
Step 1. Initialize image data generator
Here we figure out what changes we want to make to the original image and generate the augmented images
You can read up about the diff effects here- https://keras.io/preprocessing/image/
datagen = ImageDataGenerator(rotation_range=10, width_shift_range=0.1,
height_shift_range=0.1,shear_range=0.15,
zoom_range=0.1,channel_shift_range = 10, horizontal_flip=True)
Step 2: Here we pick the original image to perform the augmentation on
read in the image
image_path = 'C:/Users/Darshil/gitly/Deep-Learning/My
Projects/CNN_Keras/test_augment/caty.jpg'
image = np.expand_dims(ndimage.imread(image_path), 0)
step 3: pick where you want to save the augmented images
save_here = 'C:/Users/Darshil/gitly/Deep-Learning/My
Projects/CNN_Keras/test_augment'
Step 4. we fit the original image
datagen.fit(image)
step 5: iterate over images and save using the "save_to_dir" parameter
for x, val in zip(datagen.flow(image, #image we chose
save_to_dir=save_here, #this is where we figure out where to save
save_prefix='aug', # it will save the images as 'aug_0912' some number for every new augmented image
save_format='png'),range(10)) : # here we define a range because we want 10 augmented images otherwise it will keep looping forever I think
pass
The flow_from_directory
method gives you an "iterator", as described in your output. An iterator doesn't really do anything on its own. It's waiting to be iterated over, and only then the actual data will be read and generated.
An iterator in Keras for fitting is to be used like this:
generator = dataset.flow_from_directory('/home/1',target_size=(50,50),save_to_dir='/home/resized',class_mode='binary',save_prefix='N',save_format='jpeg',batch_size=10)
for inputs,outputs in generator:
#do things with each batch of inputs and ouptus
Normally, instead of doing the loop above, you just pass the generator to a fit_generator
method. There is no real need to do a for loop:
model.fit_generator(generator, ......)
Keras will only save images after they're loaded and augmented by iterating over the generator.
Its only a declaration, you must use that generator, for example, .next()
from keras.preprocessing.image import ImageDataGenerator
dataset=ImageDataGenerator()
image = dataset.flow_from_directory('/home/1',target_size=(50,50),save_to_dir='/home/resized',class_mode='binary',save_prefix='N',save_format='jpeg',batch_size=10)
image.next()
then you will see images in /home/resized