Very simple Gender Recognition

In this article, I will try to provide you the simplest TensorFlow Gender Recognition implementation using TensorFlow.

GitHub: https://github.com/aruno14/genderRecognition

First, the data

We will use UTKFace Dataset.

• https://www.kaggle.com/jangedoo/utkface-new

Then, the code

We use MobileNetV2 Model in order to keep the model small and usable on small devices.

import tensorflow as tf
from tensorflow.keras.preprocessing.image import ImageDataGenerator
import pandas
import glob
image_size = (48, 48)
batch_size = 32
epochs = 15
folders = ["UTKFace/"]
countCat = {0:0, 1:0}
class_weight = {0:1, 1:1}
data, labels = [], []
for folder in folders:
    for file in glob.glob(folder+"*.jpg"):
        file = file.replace(folder, "")
        age, gender = file.split("_")[0:2]
        age, gender = int(age), int(gender)
        countCat[gender]+=1
        data.append(folder + file)
        labels.append(str(gender))
minVal = min(countCat.values())
for key in class_weight:
    class_weight[key]/=countCat[key]
    class_weight[key]*=minVal
print(class_weight)
train_df = pandas.DataFrame(data={"filename": data, "class": labels})
train_datagen = ImageDataGenerator(rescale=1./255, validation_split=0.2, horizontal_flip=True)
train_generator = train_datagen.flow_from_dataframe(
        dataframe=train_df,
        x_col="filename",
        y_col="class",
        shuffle=True,
        target_size=image_size,
        batch_size=batch_size,
        subset='training',
        class_mode='categorical')
validation_generator = train_datagen.flow_from_dataframe(
        dataframe=train_df,
        x_col="filename",
        y_col="class",
        shuffle=True,
        target_size=image_size,
        batch_size=batch_size,
        subset='validation',
        class_mode='categorical')
print(train_generator.class_indices)
classifier = tf.keras.applications.mobilenet_v2.MobileNetV2(include_top=True, weights=None, input_tensor=None, input_shape=image_size + (3,), pooling=None, classes=2)
classifier.compile(loss='categorical_crossentropy', metrics=['accuracy'])
classifier.fit(train_generator, steps_per_epoch=train_generator.samples//batch_size, epochs=epochs, validation_data=validation_generator, validation_steps=validation_generator.samples//batch_size, class_weight=class_weight)
classifier.save("gender_model")

Folder structure

• /train_gender.py
• /UTKFace/*jpg

Fitting result

We obtain an accuracy of 0.8944 after 15 epochs.

Fitting history

What about grayscale?

In order to reduce model size, we can use grayscale image.

Code: https://github.com/aruno14/genderRecognition/blob/main/train_gender_grayscale.py

We obtained an accuracy of 0.9265 after 15 epochs.

Let’s convert both model into TensorFlow Lite.

tflite_convert --saved_model_dir=model_reco/ --output_file=model.tflite

RGB model size is 8.9 MB and Grayscale one is 8.9 MB; the same size.