In this article, I will summarize my journey to webcam image and audio processing.

First the code of the project on GitHub

Image processing

For image processing, we use cv2 module.

Test webcam

import cv2video = cv2.VideoCapture(1)#Change device number if needed
fps = int(video.get(cv2.CAP_PROP_FPS))
width = int(video.get(cv2.CAP_PROP_FRAME_WIDTH))
height = int(video.get(cv2.CAP_PROP_FRAME_HEIGHT))
print(fps, width, height)
while True:
grabbed, frame =
print("====New frame====")
frame = cv2.resize(frame, (width//2, height//2))
cv2.imshow("Video", frame)
if cv2.waitKey(2) & 0xFF == ord("q"):


Detect face and create mean image

The mean image is created using the average pixel value of all detected faces during time. In next section, we will use this image as input of our machine prediction model.

import cv2 import…

We often have to deal with very long lists of element, like audio data, and sometimes we want to reduce size to increase processing speed. There are many functions for image but not for 1dim array. I propose you my solution using only NumPy function.

Here is my solution !

def resize(inputArray, newLength):
block_size = len(inputArray)//newLength
outputArray = inputArray[0:block_size*newLength].reshape((block_size, newLength))
outputArray = np.mean(outputArray, axis=0)//np.max/np.min...
outputArray = outputArray.reshape((newLength))
return outputArray

We reshape the array into a 2dims array constituted of block we will represent by one element using Mean, Max, Min or any function you want to use to reduce size of your array.

Note: this method only works to reduce size and cannot be used to increase the size of the array.

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When you heard about Gender Recognition you think about Image Processing; however, we can also identify gender using Voice.

Let’s try!

First, check how we can do Gender Recognition using image.

Then, we can check some audio processing:

After that, we download audio dataset:

Dataset contains below labels including the gender (not for all files):

client_id path sentence up_votes down_votes age gender accent locale segment

The Model

First, search example

Then, find data

Let’s make something by ourselves

Basic idea

We want to create a model which predict the gain to apply to noisy frequencies to close clear frequencies.

We use STFT to obtain spectrogram of the input, then we predict and apply the gain to it, and finally we use inverse STFT to reconstruct a waveform.

Waveform to Spectrogram

def audioToTensor(filepath:str): audio_binary = audio, audioSR = audioSR = tf.get_static_value(audioSR) audio = tf.squeeze(audio, axis=-1) frame_step = int(audioSR * 0.008)#16000*0.008=128 spectrogram = tf.signal.stft(audio, frame_length=frame_length, frame_step=frame_step)#->31hz, si 512 -> 64hz spect_image = tf.math.imag(spectrogram) spect_real = tf.math.real(spectrogram) spect_sign = tf.sign(spect_real) spect_real = tf.abs(spect_real) return spect_real, spect_image, spect_sign, audioSR…

This article compares the different Audio Representations implemented in TensorFlow and TensorFlowIO.

Load the file

audio =
audioSR = int(audio.rate.numpy())
audio = audio[:]
audio = tf.squeeze(audio, axis=-1)
audio = tf.cast(audio, tf.float32)


plt.figure("Oscillo: " + filepath)
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Oscillogram of word “go”

Shape: (16000,)

Spectrogram: tf.signal.stft()

frame_step = int(audioSR * 0.008)
spectrogram = tf.abs(tf.signal.stft(audio, frame_length=1024, frame_step=frame_step))
plt.figure("Spect: " + filepath)

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


First, the data

We will use UTKFace Dataset.

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)…

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


First, the data

We will use FER2013 Dataset.

Then, the code

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

import tensorflow as tf
from tensorflow.keras.preprocessing.image import ImageDataGenerator
image_size = (48, 48)
batch_size = 32
epoch = 15
train_datagen = ImageDataGenerator(rescale=1./255, validation_split=0.2, horizontal_flip=True)
test_datagen = ImageDataGenerator(rescale=1./255)
train_generator = train_datagen.flow_from_directory(
validation_generator = test_datagen.flow_from_directory(
classifier = tf.keras.applications.mobilenet_v2.MobileNetV2(include_top=True, weights=None, input_tensor=None, input_shape=image_size + (1,), pooling=None, classes=7)
classifier.compile(loss='categorical_crossentropy', metrics=['accuracy']), steps_per_epoch=train_generator.samples//batch_size, epochs=epochs, validation_data=validation_generator, validation_steps=validation_generator.samples//batch_size)"emotion_model")

Folder structure

  • /
  • /emotions/[test, train]/[angry, disgust, fear, happy, neutral, sad, surprise]/+.jpg

Fitting result

I obtained an accuracy of 0.4873 after 15 epochs, however progression is not over.

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Fitting history

Nowadays, we can use high precision voice recognition in our smartphone or any smart devices. However, those systems are provided by big companies like Google, Amazon or Apple, and are not free.

Many people, including myself, thought that it was because of a lack of free data. However, nowdays, we can easily find free data on the Internet.

Voice datasets

Dataset sizes for some languages (2020/10/12)

  • English → 50 GB
  • German → 16GB
  • French → 15GB
  • Japanese → 265MB

Some other data here:


Maybe, it was because no tools are available…


Working in computer science.

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