Cristian P, Developer in San Francisco, CA, United States
Cristian is available for hire
Hire Cristian

Cristian P

Verified Expert  in Engineering

Deep Learning Developer

Location
San Francisco, CA, United States
Toptal Member Since
December 8, 2022

Cristian has four years of experience in Computer Vision (CV) and Machine Learning (ML). He has worked in natural language processing, autonomous driving at startups, and face tracking at Oculus. Running throughout the whole ML system lifecycle, from training models to testing and serving behind an application interface. Cristian enjoys curating datasets and can communicate with all teams to articulate results while researching tooling, frameworks, and papers needed for an optimal solution.

Availability

Part-time

Preferred Environment

PyTorch, Python 3, JavaScript, Bash, NumPy, Pandas, SQL, C++11

The most amazing...

...project I've built is a data pipeline for face key-point estimation, an evaluation of object classification, and multi-class, multi-label classification.

Work Experience

Research Engineer

2021 - 2022
Meta
  • Managed language models pre-training and fine-tuning to detect privacy-sensitive artifacts, trained and optimized the BERT model, which improved evaluation metrics by 2% over the baseline.
  • Collaborated with XFN teams and sourced 3–5 million data points to create training datasets and ingest them into BERT models.
  • Facilitated implementation of service API for serving the BERT model unlocking new use cases for three teams.
Technologies: PyTorch, SQL, NumPy, Pandas, Matplotlib, Bash

Research Engineer

2019 - 2021
Oculus
  • Designed and implemented a resilient data pipeline for ingesting, prioritizing, and sampling video data for key-point labeling to automate acquiring raw data and getting it labeled.
  • Analyzed and benchmarked different models for face-tracking and collaborated with the mobile device team to deploy the best face-tracking model to specialized hardware.
  • Collaborated with the data operations team and implemented key-frame detection and active learning sampling methods, reducing the need for data annotation by 30%.
Technologies: PyTorch, SQL, NumPy, Pandas, PHP, Bash

Computer Vision Research Engineer

2018 - 2019
Cognition Factory
  • Implemented a modular and configurable pipeline to collect labeled images on new objects and fine-tune object detection models.
  • Investigated and re-ordered Numpy operations to improve the latency of Yolo darknet Python implementation.
  • Developed a background segmentation feature to crop out objects so that the object classification models can be trained on data generated with that object.
Technologies: PyTorch, Python 3

Computer Vision Intern

2017 - 2018
Motional
  • Developed a plane detection and segmentation algorithm to partition lidar maps.
  • Created a feature in the labeling tool to detect inconsistent lidar maps to reduce annotation time by 20%.
  • Implemented UI features in the labeling tool using the Qt framework.
Technologies: C++11, PCL, OpenCV, Qt 4, Bash

Part-time Computer Vision Engineer

2016 - 2017
Cognition Factory
  • Implemented a fish-eye lens camera calibration method from a paper.
  • Developed triangulation methods and integrated them into a SLAM pipeline.
  • Created an end-to-end monocular up-to-scale visual odometry pipeline.
Technologies: C++11, Python 3, OpenCV, PyTorch, Ceres

Object Multi-Label Classification

The project was about detecting multiple tools in an image. I did an exploratory data analysis, then developed a baseline multi-label Convolutional Neural Network based classification model. After that, I iterated on improving the metrics of the model with various ideas, such as trying out different pre-trained object classification networks, loss functions, and data augmentation techniques.
2015 - 2018

Master's Degree in Machine Learning and Computer Vision

Technical University of Munich - Munich

2011 - 2015

Bachelor's Degree in Computer Science

Technical University of Munich - Munich

SEPTEMBER 2018 - PRESENT

Structure Machine Learning Projects

Coursera

AUGUST 2018 - PRESENT

Neural Networks and Deep Learning

Coursera

Libraries/APIs

PyTorch, NumPy, OpenCV, Pandas, PCL, Matplotlib

Languages

Python 3, Python, SQL, JavaScript, Bash, C++11, C++, PHP

Other

Deep Learning, Object Detection, Object Classification, Image Processing, Ceres, Qt 4, Machine Learning, Natural Language Processing (NLP), Language Models, GPT, Generative Pre-trained Transformers (GPT)

Collaboration That Works

How to Work with Toptal

Toptal matches you directly with global industry experts from our network in hours—not weeks or months.

1

Share your needs

Discuss your requirements and refine your scope in a call with a Toptal domain expert.
2

Choose your talent

Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.
3

Start your risk-free talent trial

Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.

Top talent is in high demand.

Start hiring