Tensorflow

TensorFlow is an open source library that was created by Google. It is used to design, build, and train deep learning models.

GitHub: https://github.com/topics/tensorflow
Wikipedia: https://en.wikipedia.org/wiki/TensorFlow
Repo: https://github.com/tensorflow
Created by: Google Brain Team
Released: November 9, 2015
Aliases: tensorflow-tutorials, tensorflow-experiments, tensorflow-models, tensorflow-examples, tensorflow-1-0, tensorflow-tutorial,
Last updated: 2026-07-05 00:25:04 UTC
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https://github.com/pra17dod/waste-segregation

Waste Segregation @HackBash2021 : ML based deployed waste segregation web app

flask heroku machine-learning react tensorflow waste-management waste-segregation

Last synced: 13 Apr 2025

https://github.com/nikhilroxtomar/attention-mechanism-implementation

Implementation of different attention mechanisms in TensorFlow and PyTorch.

attention-mechanism pytorch squeeze-and-excitation tensorflow

Last synced: 26 Jul 2025

https://github.com/andfanilo/ddsp-streamlit-ui

Streamlit version for the DDSP timbre transfer demo.

ddsp python streamlit tensorflow

Last synced: 02 Jul 2025

https://github.com/jdpigeon/tfreactnative

A test React Native app with Tensorflow

android react-native tensorflow

Last synced: 11 Apr 2025

https://github.com/lalitdotdev/watchtowerai

An AI-powered web application leveraging Next.js 14 and TensorFlow.js for real-time object detection. Utilizing Tensorflow model for accurate detection, webcam integration for live video streams, and Media Recorder API for seamless recording.

aceternity ai cocossd framer-motion machine-learning mediarecorder-api multimedia multimedia-systems nextjs14 object-detection persondetaction react-webcam shadcn-ui surveillance-systems tailwindcss tensorflow tensorflowjs-model typescript

Last synced: 19 Jul 2025

https://github.com/linchuming/imagesr-tensorflow

An image super-resolution implemented by Tensorflow

image-super-resolution tensorflow

Last synced: 14 Jun 2025

https://github.com/mukeshmithrakumar/scientific

TensorFlow scientific is a library for scientific computing

python tensorflow tensorflow-scientific

Last synced: 26 Oct 2025

https://github.com/sandeepvashishtha/image-recognition

Identify and classify objects in real-time video streams using TensorFlow and OpenCV. This project is designed for applications like security systems, robotics, and interactive installations, combining the power of TensorFlow for deep learning with OpenCV's webcam interaction.

collaborate image-classification imagerecognition keras-classification-models keras-tensorflow object-detection objectrecognition opencv python3 tensorflow

Last synced: 08 Apr 2025

https://github.com/amitkumarj441/identify_pneumonia

Mask-RCNN based model to automatically identify potential pneumonia cases

computer-vision mask-rcnn pneumonia-detection pytorch resnet tensorflow

Last synced: 13 Aug 2025

https://github.com/belval/bitcoinrnn

A Recurrent Neural Network using Tensorflow to predict Bitcoin price

bitcoin recurrent-neural-networks tensorflow

Last synced: 12 Apr 2025

https://github.com/Himscipy/bnn_hvd

Distributed Training of Bayesian Neural Networks at Scale

bayesian-networks computer-vision data-science distributed-computing horovod machine-learning mnist tensorflow tensorflow-probability uncertainty-quantification variational-inference

Last synced: 15 Jul 2025

https://github.com/dunky11/piracy-resistant-watermarks

Implemention of "Piracy Resistant Watermarks for Deep Neural Networks" in TensorFlow.

keras neural-network piracy-resistance tensorflow tensorflow2 watermark watermarking

Last synced: 10 Apr 2025

https://github.com/zukarusan/jchoreco

Java automatic chord recognition with neural network and digital signal processing.

audio-processing chord-recognition chromagram deep-learning java java-api-tensorflow keras-tensorflow machine-learning music neural-network signal-processing stft tarsos tarsosdsp tensorflow

Last synced: 13 May 2025

https://github.com/soheil-mp/natural-language-processing-tutorials

NLP Webinars Created for Udacity's Mentorship Program (2019).

alexa-skill embeddings feature-extraction hidden-markov-model ibm-bluemix keras natural-language-processing parts-of-speech pytorch sequence-to-sequence spam-detection tensorflow text-processing topic-modeling

Last synced: 02 Aug 2025

https://github.com/elggem/tensorflow_node

Tensorflow based ROS node for evaluating deep learning algorithms.

artificial-intelligence artificial-neural-networks autoencoder deeplearning ros ros-node science tensorflow

Last synced: 07 Jul 2025

https://github.com/zotroneneis/deep_music

Recurrent neural network in TensorFlow for generating novel monophonic melodies.

neural-network python3 recurrent-neural-network recurrent-neural-networks tensorflow variational-autoencoder variational-autoencoders

Last synced: 30 Apr 2025

https://github.com/abhifuturetech/ann-robotics-simu

This project focuses on developing and implementing neural network algorithms to enable autonomous navigation in self-driving robots.

keras neural-network opencv python raspberry-pi robotics tensorflow

Last synced: 09 Jul 2025

https://github.com/selenecodes/GPU-jupyterhub

A basic jupyterhub with Nvidia GPU accessibility.

cuda cuda-toolkit docker-compose docker-container docker-deployment docker-volumes gpu-computing jupyter jupyter-notebook jupyterhub scipy tensorflow

Last synced: 04 May 2025

https://github.com/benedekrozemberczki/graf

Inner product natural graph factorization machine used in 'GEMSEC: Graph Embedding with Self Clustering' .

clustering community community-detection deepwalk embedding factorization graph graph-embedding implicit-factorization machine-learning matrix-factorization node-embedding node2vec semisupervised-learning struc2vec structural-embedding tensorflow unsupervised-learning word2vec

Last synced: 11 Apr 2025

https://github.com/minar09/u-net-attention

U-Net + Attention, extending U-Net model for semantic segmentation. Implemented with TensorFlow.

attention attention-gate attention-model attention-to-scale encoder-decoder multi-scale semantic-segmentation tensorflow u-net

Last synced: 11 Apr 2025

https://github.com/thomasgust/pymuse

PyMuse is a python tool to generate music and art with the help of artificial intelligence.

ai alpha art artificial-intelligence generation music neural-network neural-style-transfer python python3 tensorflow

Last synced: 16 Jul 2025

https://github.com/sayakpaul/evonorms-in-tensorflow-2

Implements EvoNorms B0 and S0 as proposed in Evolving Normalization-Activation Layers.

automl-products deep-learning keras tensorflow

Last synced: 07 May 2025

https://github.com/sayannath/mobilevit-gsoc

Implementation of MobileViT in TensorFlow and Keras

tensorflow

Last synced: 01 Mar 2026

https://github.com/thevarunsharma/Image-Colorization

Automatic Image Colorization using a Convolutional Network (U-Net)

convolutional-neural-networks deep-learning flask-application image-colorization keras machine-learning python tensorflow

Last synced: 07 May 2025

https://github.com/imsanjoykb/bunch-of-computer-vision-projects

Bunch of Computer Vision Projects

computer-vision deep-learning digit-recognition face-recognition faceeye-detecton facial-expression-recognition haar-cascade-classifier image-classification image-dataset imagedata-resource livesketch object-tracking pedestrian-detection pytorch-implementation tensorflow yolo yolov5

Last synced: 30 Oct 2025

https://github.com/hanabi1224/tensorflow-batteries

Nuget package that provides tensorflow prebuilt dlls

tensorflow tensorflowsharp

Last synced: 12 May 2025

https://github.com/aazhar/keras2tensorflow

Tutorial on running keras model in C++ and python tensorflow

cpp keras keras-tensorflow python tensorflow

Last synced: 13 Apr 2025

https://github.com/fabianmurariu/website-categories-nn

Build a deep learning model predicting categories from dmoz datasource

deep-learning deep-neural-networks keras spark tensorflow

Last synced: 10 Apr 2025

https://github.com/kweinmeister/notebooks

Jupyter notebooks for learning and demonstrations

machine-learning notebook python tensorflow

Last synced: 23 Jun 2025

https://github.com/alshedivat/cen

Contextual Explanation Networks (CEN).

deep-learning explainability interpretability keras machine-learning tensorflow

Last synced: 07 May 2025

https://github.com/osamhack2020/iot_covid19-detector_co-vision

Identify and Alert people at risk of COVID-19 infection in REAL-TIME using raspberry-pi.

deep-learning face-mask-detection flir-lepton iot keras opencv osam python raspberry-pi telegram-bot tensorflow

Last synced: 04 May 2025

https://github.com/pratikpc/tf-kmeans

A Tensorflow.JS Library for Calculating KMeans

kmeans kmeans-clustering npm-package tensorflow tensorflowjs tf tfjs

Last synced: 09 Oct 2025

https://github.com/vladmandic/insightface

InsightFace for TFJS

face-recognition insightface tensorflow tfjs

Last synced: 24 Oct 2025

https://github.com/benchopt/benchmark_resnet_classif

Benchopt benchmark for ResNet fitting on a classification task

benchmark deep-learning image-classification optimization pytorch resnet tensorflow

Last synced: 19 Oct 2025

https://github.com/vvmnnnkv/s4tf-style-transfer-service

Vapor-based HTTP API serving style transfer model made in Swift for TensorFlow

deep-learning s4tf swift tensorflow vapor

Last synced: 22 Apr 2025

https://github.com/unity-technologies/go-tensorgen

Lightweight tool that generates Go structures and Tensorflow inference execution code from SavedModel

cgo codegen codegenerator go golang savedmodel tensorflow

Last synced: 19 Oct 2025

https://github.com/akb89/word2vec

Re-implementation of Word2Vec using Tensorflow v2 Estimators and Datasets

tensorflow tensorflow-datasets tensorflow-estimators tensorflow2 word2vec

Last synced: 14 Mar 2026

https://github.com/moon0922/control-3d-model-by-facelandmark

This is the react project to control glb model in real-time using face landmark detection and three.js

3dmodel deep-learning react tensorflow tensorflowjs threejs web webcam

Last synced: 02 Aug 2025

https://github.com/pitmonticone/reddittextclassification

Reddit Gender Text-Classification.

algorithms artificial-intelligence computer-science data-analysis data-mining data-science data-visualization jupyter-notebook keras-tensorflow language-model machine-learning modeling natural-language-processing neural-network nlp python reddit scikit-learn spacy-nlp tensorflow

Last synced: 24 Oct 2025

https://github.com/en10/kerasinception

Google Inception-V3 with Keras

image-classification image-recognition inception-v3 inceptionv3 keras keras-tensorflow tensorflow

Last synced: 12 Mar 2026

https://github.com/t73liu/tfjs-starter

TensorFlow.js application that uses MobileNet to detect objects.

expo javascript react-native tensorflow

Last synced: 11 Mar 2026

https://github.com/robinka/metavae

Meta-learning by applying MAML to an inner variational auto-encoder to automatically learn generative models with few examples

deep-learning few-shot-learning generative-models machine-learning maml metalearning neural-network one-shot-learning tensorflow vae

Last synced: 31 Jul 2025

https://github.com/sparkier/luna

Luna is inspired by Lucid, a framework for Feature Visualization. However, Luna is built on Tensorflow 2, and thus supports modern models and deep learning techniques.

artificial-intelligence deep-learning machine-learning tensorflow visualization

Last synced: 13 Mar 2026

https://github.com/zhanpenghe/capsule-network

Keras and tensorflow implementation of capsule network.

capsnet capsule-network dynamic-routing keras tensorflow

Last synced: 26 Apr 2025

https://github.com/dcos-labs/dcos-jupyterlab-service

JupyterLab Notebook for Mesosphere DC/OS

arrow beakerx cudnn dask dcos gpu hdfs jupyter jupyterlab keras marathon mesos mesosphere pandas ray rllib spark tensorflow toree xgboost

Last synced: 06 Mar 2026

https://github.com/epsoft/explainable

explainable

data database dataset explainable numpy seaborn tensorflow

Last synced: 29 Jul 2025

https://github.com/kleinyuan/tf-blocks

Building blocks of tensorflow architectures

cnn tensorflow training

Last synced: 12 Apr 2025

https://github.com/arose13/rosey

Data science utilities for statistics and machine learning

data-science data-visualization keras machine-learning tensorflow

Last synced: 24 Oct 2025

https://github.com/tf-encrypted/tf-big

Arbitrary precision integers in TensorFlow

cryptography machine-learning tensorflow

Last synced: 09 Apr 2025

https://github.com/evernext10/recognition-objects-and-hand-gesture-with-tensorflow-and-firebase-cloud-vision-android

android experiments firebase firebase-cloud-vision hand-gesture-recognition java machine-learning recoginition-object recognition tensorflow

Last synced: 09 Oct 2025

https://github.com/thundergolfer/reasoning-about-entailment-tensorflow

:school: Tensorflow implementation of "Reasoning About Entailment with Neural Attention"

deepmind implementation machine-learning natural-language-inference natural-language-processing tensorflow

Last synced: 06 Jul 2025

https://github.com/isaaccorley/making-convolutional-networks-shift-invariant-again-tensorflow

Tensorflow Implementation of BlurPool the Antialiasing Pooling operation from "Making Convolutional Networks Shift-Invariant Again"

antialiasing artificial-intelligence computer-vision keras tensorflow

Last synced: 08 Oct 2025

https://github.com/sonu275981/gtsrb---german-traffic-sign-recognition

GTSRB - German Traffic Sign Recognition

convolutional-neural-networks deep-learning german-traffic-sign-classifier gtsrb-dataset keras neural-network python tensorflow

Last synced: 19 Oct 2025

https://github.com/arthurdouillard/tensorflow-faceid

Faceid-like in Tensorflow using a Siamese network with contrastive loss

deep-learning face-recognition siamese-network tensorflow

Last synced: 26 Oct 2025

https://github.com/resotto/laplace

LSTM Model to predict BTCUSD ticker values

bidirectional-lstm deep-learning keras lstm numpy python python3 recurrent-neural-networks scikit-learn sklearn tensorflow

Last synced: 02 Jul 2025

https://github.com/singh1aryan/med-tracker

🏥 Health tracking app for daily activities

android android-application database firebase firebase-authentication firebase-firestore firebase-functions firebase-realtime-database hackathon-project hackumass health-tracker machine-learning materialdesignicons medical mlkit mobile-development open-source python tensor-flow tensorflow

Last synced: 16 Oct 2025

https://github.com/animikhaich/alexnet-tensorflow

GPU Optimized AlexNet Implementation to train on ImageNet 2012 using Tensorflow 2.x

alexnet alexnet-tensorflow imagenet implementation paper python tensorflow tensorflow-datasets tensorflow2 tfdata

Last synced: 16 Aug 2025

https://github.com/sergio11/safedrive_drowsiness_detection

🚗 Driver Drowsiness Detection with Deep Learning (PoC) 🧠 A personal experiment comparing CNN + MobileNetV2 and YOLOv11 for real-time drowsiness detection. Focused on evaluating accuracy and efficiency to explore AI’s potential in preventing fatigue-related accidents. 😴⚡ A hands-on dive into safety-driven computer vision.

autonomous-driving computer-vision convolutional-neural-networks deep-learning driver-drowsiness-detection image-classification mobile-ai real-time-detection tensorflow tensorflow-lite transfer-learning yolo yolov11

Last synced: 04 Oct 2025

https://github.com/tensorlayer/tlxcv

A Platform-agnostic Computer Vision Application Library

computer-vision mindspore paddlepaddle pytorch tensorflow tensorlayer tensorlayerx

Last synced: 24 Apr 2025

https://github.com/taki0112/discogan-tensorflow

Simple Tensorflow implementation of DiscoGAN

discogan discogan-tensorflow tensorflow

Last synced: 09 Apr 2025

https://github.com/adamdad/samesame

An Tensorflow.keras implementation of Same, Same But Different - Recovering Neural Network Quantization Error Through Weight Factorization(https://arxiv.org/pdf/1902.01917.pdf) ---ICML2019

cnn equalization quantization tensorflow weight-factorization

Last synced: 29 Jun 2025

https://github.com/zhaocc1106/machine_learn

机器学习与深度学习

deep-learning machine-learning tensorflow

Last synced: 23 Mar 2025

https://github.com/muayyad-alsadi/master-thesis-cnn

Master Thesis: Image recognition by knowledge transfer using deep convolutional neural network

cnn machine-learning neural-networks tensorflow transfer-learning

Last synced: 25 Oct 2025

https://github.com/n3pdf/evolutionary_keras

An evolutionary algorithm implementation for Keras

evolutionary-algorithm genetic-algorithm keras machine-learning open-source python tensorflow

Last synced: 23 Apr 2025

https://github.com/googlecreativelab/visual-alarm-clock

Get up in the morning by striking a pose to stop your alarm from ringing.

arduino microcontroller tensorflow

Last synced: 26 Oct 2025

https://github.com/ukjin1192/tensorflow-minesweeper

Proof of concept for using TensorFlow to improve AI at this Minesweeper game

machine-learning minesweeper-game tensorflow tensorflow-experiments

Last synced: 24 Oct 2025

https://github.com/devfemibadmus/human-pose-estimation

This project focuses on Human Pose Estimation using the MoveNet model with TensorFlow Lite. The goal is to detect keypoint positions on a person's body in images and live video frames. The project provides a Flask web application for both image and live video input, showcasing the real-time capabilities of the model.

flask-ai human-pose-estimation human-pose-tracking movenet movenet-lightning movenet-thunder python tensorflow

Last synced: 14 Oct 2025

https://github.com/x-raylaser/multi-directional-mdrnn

Custom Keras layers for implementing multi-dimensional recurrent neural networks (MDRNNs) described in Alex Graves's paper https://arxiv.org/pdf/0705.2011.pdf

deep-learning keras lstm machine-learning mdrnn multi-dimensional-rnn neural-networks paper-implementations recurrent-neural-networks rnn tensorflow

Last synced: 26 Oct 2025

https://github.com/gimnathperera/molemi-app

Molemi App is a AI (Deep Learning) based plant disease recognition application that can identify up to 10 various types of plant diseases by analyzing plant leaves.

cnn deep-learning expo flask mysql reactnative tensorflow

Last synced: 30 Apr 2025

https://github.com/shrikantnaidu/bert-for-text-classification-with-tensorflow

bert-fine-tuning natural-language-processing tensorflow transfer-learning

Last synced: 29 Apr 2025

https://github.com/compwa/tensorwaves

Python fitter package for multiple computational back-ends

cas jax minimizer optimizer python sympy tensorflow

Last synced: 26 Oct 2025

https://github.com/hoangsonww/ai-ml-classifiers

🌟 This repository houses a collection of image classification models for various purposes, including vehicle, object, animal, and flower classification. Each classifier is built using deep learning techniques and pre-trained models to accurately identify and categorize images based on their respective classes.

ai ai-classifier animal-classification artificial-intelligence classification classifier face-recognition keras keras-tensorflow machine-learning mood-detection ocr opencv python tensorflow tesseract vehicle-classification vehicle-detection

Last synced: 11 Apr 2025

https://github.com/neelanjan00/image-forgery-detection

A deep convolutional neural network for the detection as well as localization of the area of manipulation in forged images, bearing forgeries of simple as well as complex nature. Further along, the trained model is interfaced with a web application for users to interact with the model in a simple and effective manner, and finally, we also develop a chatbot for further easing the process of interaction with the model and effectively tackling the problem of fake news forwards in popular internet messaging platforms such as WhatsApp.

chatbot computer-vision deep-learning flask forgery-detection tensorflow

Last synced: 11 Oct 2025

https://github.com/ugnelis/find-path

Find path by using Semantic Segmentation.

dataset dataset-maker fcn-16s ipynb semantic-segmentation tensorflow vgg16

Last synced: 02 Oct 2025

https://github.com/gentaiscool/cnn-autoencoder-tf

CNN and Contrastive Autoencoder (CAE) on EMNIST using Tensorflow

autoencoder cae cnn contrastive emnist tensorflow

Last synced: 17 Mar 2026

https://github.com/beomso0/ezsasrec

An easy and efficient tool to build sequential recommendation system utilizing SASRec

recommendation recommendation-algorithm recommendation-system recommendations recommender recommender-system recommender-systems sasrec sasrec-tf sequential sequential-models sequential-recommendation tensorflow

Last synced: 05 Mar 2026

https://github.com/harrymt/rate-my-plate

Rate My Plate, Twitter Bot to rate the environmental impact of your food.

flask tensorflow tweepy

Last synced: 12 Jun 2026

https://github.com/nguyenducquan12/ibm-ai-engineering-professional-certificate

Mô tả quá trình mình bắt đầu học để trở thành kỹ sư AI bằng khóa học IBM AI Engineering Professional Certificate

ai coursera ibm ibm-ai-engineering-professional-certificate tensorflow

Last synced: 08 Jun 2026

https://github.com/smaranjitghose/deepholi

A deep learning application to simulate Holi effect for your group pictures.

art deep-learning gans python tensorflow

Last synced: 02 Mar 2026

https://github.com/andi611/conditional-specgan-tensorflow

Text-to-Speech Synthesis by Generating Spectrograms using Generative Adversarial Network

audio-synthesis conditional-gan digital-signal-processing gan librosa machine-learning nlp nlp-machine-learning tensorflow tts

Last synced: 13 Apr 2025

https://github.com/faust-prime/X-ray-images-classification-with-Keras-TensorFlow

ConvNet (CNN) implementation to classify x-ray medical images

augmentation cnn cnn-for-visual-recognition cnn-keras cnn-tensorflow computer-vision keras-implementations keras-layer keras-neural-networks medical medical-image-analysis medical-image-processing tensorflow tensorflow-examples

Last synced: 09 May 2025

https://github.com/thealoneprogrammer/emotion-recognition-juke-box

django emotion emotion-analysis emotion-based-music-app emotion-based-music-player emotion-detection emotion-recognition facerecognition music music-player opencv python song tensorflow

Last synced: 11 Apr 2025

https://github.com/doubangotelecom/ultimatekyc-sdk

Know Your Customer (KYC) implementation using identity document OCR, face match, biometric liveness detection for Anti-Spoofing and much more

ai android biometrics deep-fake deeplearning epassport face-detection face-matching face-recognition ios kyc linux liveness liveness-detection nfc ocr security tensorflow windows

Last synced: 26 Mar 2025

https://github.com/shoamco/Mobileye-Project

Traffic light detection

numpy opencv python3 tensorflow traffic-light-detection

Last synced: 09 May 2025

https://github.com/chen0040/java-audio-embedding

Audio classifier, encoder, and search engine in Java

audio-classification audio-encoder audio-search-engine genres keras music-classification search-engine tensorflow

Last synced: 16 Oct 2025

https://github.com/skulltech/cinembers

Generating numbers from movies, one movie at a time.

image-processing movies python shots tensorflow

Last synced: 16 Oct 2025

https://github.com/sayannath/vit-tf-hub-application

Build and fine-tune your Image Classifier using a Vision Transformer Model from TensorFlow Hub

fine-tuning jax keras tensorflow tf2 tfhub transformers vision-transformer vit

Last synced: 12 May 2025

https://github.com/domarps/papers-i-read

Summaries and notes on recent Deep Learning literature

convolutional-neural-networks deep-learning long-short-term-memory-models pytorch reinforcement-learning tensorflow

Last synced: 14 Oct 2025

https://github.com/sk-g/speech-recognition-tensorflow-challenge

Different CNN Models for keyword spotting in speech recognition

alexnet-model cnn deep-learning machine-learning neural-networks speech-recognition tensorflow

Last synced: 14 Aug 2025

https://github.com/darienmt/carnd-behavioral-cloning-p3

Udacity Self Driving Car Nanodegree - Behavioral Cloning

computer-vision convolutional-neural-networks keras neural-network opencv python self-driving-car tensorflow udacity-self-driving-car visualization

Last synced: 14 Aug 2025

https://github.com/aralroca/cat-dog-detection-tfjs

Cat/Dog detection model in Tensorflow.js

machine-learning mobilenet preact react tensorflow tensorflowjs tfjs tfjs-tutorials

Last synced: 19 Apr 2025

https://github.com/kazuhito00/m-lsd-warpperspective-example

M-LSDを用いて四角形を検出し、射影変換を行うサンプルプログラム

m-lsd opencv tensorflow warpperspective

Last synced: 14 Mar 2026

https://github.com/26hzhang/bert_classification

Token and Sentence Level Classification with Google's BERT (TensorFlow)

bert-bilstm-crf bert-embeddings bert-model tensorflow

Last synced: 12 Oct 2025

https://github.com/garcane/binance-crypto-prediction-and-analysis

This project leverages the Binance API to acquire real-time data for Bitcoin (BTC) and Ethereum (ETH). The data is then used to train a Long Short-Term Memory (LSTM) neural network model for predicting cryptocurrency prices.

api binance bitcoin btc cryptocurrency eth ethereum keras machine-learning neural-networks python tensorflow