image_utils.py

import numpy as np
import scipy as sp
from PIL import Image
from scipy import misc


def imread(filename):
  """Read image from file.
  Args:
    filename: .
  Returns:
    im_array: .
  """
  im = sp.misc.imread(filename)
  return im / 255.0
  # return im / 127.5 - 1.0


def imsave(np_image, filename):
  """Save image to file.
  Args:
    np_image: .
    filename: .
  """
  # im = sp.misc.toimage(np_image, cmin=0, cmax=1.0)
  im = sp.misc.toimage(np_image, cmin=-1.0, cmax=1.0)
  im.save(filename)

def imwrite(filename, np_image):
  """Save image to file.
  Args:
    filename: .
    np_image: .
  """
  # im = sp.misc.toimage(np_image, cmin=0, cmax=1.0)
  im = sp.misc.toimage(np_image, cmin=-1.0, cmax=1.0)
  im.save(filename)

def imwrite_batch(filenames, np_images):
  """Save batch images to file.
  Args:
    filenames:
  """
  #TODO
  pass

def imresize(np_image, new_dims):
  """Image resize similar to Matlab.
  This function resize images to the new dimension, and properly handles
  alaising when downsampling.
  Args:
    np_image: numpy array of dimension [height, width, 3]
    new_dims: A python list containing the [height, width], number of rows, columns.
  Returns:
    im: numpy array resized to dimensions specified in new_dims.
  """
  # im = np.uint8(np_image*255)
  im = np.uint8((np_image+1.0)*127.5)
  im = Image.fromarray(im)
  new_height, new_width = new_dims
  im = im.resize((new_width, new_height), Image.ANTIALIAS)
  return np.array(im)