pre_process.py

import pandas as pd
import cv2
import numpy as np

dataset_path = 'data/train.csv'  # 文件保存位置
image_size = (48, 48)  # 图片大小


# 载入数据
# faces 为表情的灰度矩阵列表 emotions 为各表情所对应的心情序号
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'])
    return faces, emotions


# 将数据归一化
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