load.py

import cv2
import numpy as np
import pandas as pd

dataset_path = 'fer2013/fer2013/fer2013.csv'
image_size=(48,48)

def load_fer2013():
    data = pd.read_csv(dataset_path)
    pixels = data['pixels'].tolist()
    width, height = 48,48
    faces = []
    for pixel_sequence in pixels:
        face = [int(pixel) for pixel in pixel_sequence.split(' ')]
        face = np.asarray(face).reshape(width, height)
        face = cv2.resize(face.astype('uint8'),image_size)
        faces.append(face.astype('float32'))

    faces = np.asarray(faces)
    faces = np.expand_dims(faces, -1)
    emotions = pd.get_dummies(data['emotion']).as_matrix()
    return faces, emotions

def preprocess_input(x, v2=True):
    x = x.astype('float32')
    x = x/255.0

    if v2:
        x = x - 0.5
        x = x*2.0

    return x