Mahmoud Afifi
Staff Research Scientist at Samsung Research America
PhD in Computer Science, York University, Canada | Supervisor: Prof. Michael S. Brown
MSc in Information Technology, Assiut University, Egypt | Supervisor: Prof. Khaled Hussain
Email: m.3[last name][at]gmail[dot]com
CV | Linkedin | Google Scholar | ResearchGate | GitHub | Mathworks | Twitter
Experience
Staff Research Scientist / Research Intern: Works on low-level computer vision, camera, and imaging technologies. As an intern, I contributed to My Filters feature (released in Samsung Galaxy S20) and developed techniques for color and exposure-error correction.
Camera Software Engineer / Student Researcher / Research Intern: Worked with Pixel team on color correction of Pixel phone cameras. As a student researcher/intern with the Gcam team, I worked on cross camera white-balance correction (C5).
Machine Learning / Camera Algorithms Engineer: Worked with Camera ISP Algorithm on color correction for iPhone cameras.
Computer Vision R&D Engineer / Consultant: Developed an ML algorithm for skin color correction and consulted on hairstyle editing and hair color matching used in LUXY HAIR virtual demo.
Consultant: Worked on image harmonization.
Research Engineer / Consultant: Developed the color correction module in NUDEMETER and consulted on skin tone analysis.
Research
I am interested in low-level computer vision and computational photography, focusing on color processing and enhancing photograph quality. Below are representative examples of my work. For a full list of publications, please take a look here.
Mostafa Hussien, Mahmoud Afifi, Kim Khoa Nguyen, and Mohamed Cheriet
arXiv, 2024
In collaboration with ÉTS, University of Quebec
We introduce a data-driven unstructured pruning method that uses training data (or a subset of it) to estimate each weight's importance based on its contribution to the corresponding node's output. Preliminary experiments show that our method consistently produces more accurate models, even at high compression rates, compared to other approaches.
Abdelrahman Abdelhamed*, Mahmoud Afifi*, and Alec Go
arXiv, 2024
With some prompt engineering, multimodal LLMs (e.g., Gemini) can perform zero-shot image classification. However, they may not consistently produce accurate target dataset labels. Our approach leverages multimodal LLMs & cross-modal embedding encoders to produce initial class prediction feature & image description feature alongside image feature, improving zero-shot image classification accuracy without the need for dataset-specific prompts. Our method outperforms prior methods across various datasets, achieving a 6.8% increase in accuracy on ImageNet.
* Equal contribution
Mahmoud Afifi, Zhenhua Hu, and Liang Liang
ECCV 2024
27.9% acceptance rateUtilizing the chromatic distortion present between long and short exposure frames of HDR photography, we introduce a compact guiding feature for illuminant estimators. Processed by just ~300 learnable parameters, it achieves results that match or surpass previous methods relying on thousands or even millions of parameters.
Paper | Supp. Materials | arXiv | Poster
Georgy Perevozchikov, Nancy Mehta, Mahmoud Afifi, and Radu Timofte
ECCV 2024
27.9% acceptance rateIn collaboration with University of Würzburg
Rawformer, an unsupervised Transformer-based encoder-decoder model for raw-to-raw mapping, enables the utilization of learnable camera ISP trained on a specific camera's raw images to render raw images taken by new cameras with different characteristics.
Paper | Supp. Materials | arXiv | Code
Mahmoud Afifi, Marcus A. Brubaker, and Michael S. Brown
WACV 2022
35% acceptance rateYork University
Mixed/single-illuminant scene white balancing does not necessarily require illuminant estimation. Instead, the problem could be bounded by a small set of predefined white-balance settings. Given that, we locally blend a set of small images rendered with different white-balance settings to generate the final corrected image.
Paper | Supp. Materials | arXiv | Code & Data | Poster | Presentation | Talk | Patent Application
Abdullah Abuolaim, Mahmoud Afifi, and Michael S. Brown
WACV 2022
35% acceptance rateYork University
Jointly learning to predict the two DP views from a single blurry input image improves the network’s ability to learn to deblur the image. Generating high-quality DP views can be used for other DP-based applications, such as reflection removal.
PDF | Supplementary Materials | arXiv | Code & Dataset | Patent Application
Mahmoud Afifi, Jonathan T. Barron, Chloe LeGendre, Yun-Ta Tsai, and Francois Bleibel
ICCV 2021 (Oral Presentation)
25.9% acceptance rate | 3% oral presentation acceptance rateGoogle Research
A self-calibration method for cross-camera color constancy through the lens of transductive inference: additional (unlabeled) images are provided as input to the model at test time, which allows the model to calibrate itself to the spectral properties of the test-set camera during inference.
Paper | Supp. Materials | arXiv | Code | Poster | Presentation | Presentation (PDF) | Talk | Google @ ICCV'21
Mahmoud Afifi, Marcus A. Brubaker, and Michael S. Brown
CVPR 2021
23.4% acceptance rateYork University
HistoGAN is the first work to control colors of GAN-generated images based on features derived directly from color histograms. Our method learns to transfer the color information encapsulated in histogram features to the colors of a GAN-generated images (HistoGAN) or real input images (ReHistoGAN). As color histograms provide an abstract representation of image color that is decoupled from spatial information, our HistoGAN and ReHistoGAN are less restrictive and suitable across arbitrary domains.
Paper | Supp. Materials | arXiv | Code & Dataset | Colab (histogram loss) | Poster | Presentation | Talk
Mahmoud Afifi, Konstantinos G. Derpanis, Björn Ommer, and Michael S. Brown
CVPR 2021
23.4% acceptance rateSamsung Research in collaboration with Heidelberg University
A single coarse-to-fine deep learning model with adversarial training to correct both over- and under-exposed photographs.
Paper | Supp. Materials | arXiv | Code & Dataset | Poster | Presentation | Talk | Samsung Research Post | Patent
Mahmoud Afifi, Abdelrahman Abdelhamed, Abdullah Abuolaim, Abhijith Punnappurath, and Michael S. Brown
TPAMI 2021
Impact factor: 20.8 (2023)York University
Learning an accurate camera-rendering linearization gives a significant improvement for different computer vision tasks (e.g., denoising, deblurring, and image enhancement).
Paper | arXiv | Supp. Materials | External Link | Code & Dataset
Mahmoud Afifi and Abdullah Abuolaim
BMVC 2021
York University
A semi-supervised method to map between two different camera-raw spaces. Training requires an unpaired set of images besides a very small set of paired images taken by these two camera models.
arXiv | Dataset | Presentation
Mahmoud Afifi and Michael S. Brown
CVPR 2020 (Oral Presentation)
22.1% acceptance rate | 5.7% oral presentation acceptance rateSamsung Research
A multi-task deep learning model for post-capture white-balance correction and editing
Paper | Supp. Materials | arXiv | Code | Presentation | Talk | CVPR Daily Magazine | Samsung Research Post | Samsung Newsroom | Patent
Abhijith Punnappurath, Abdullah Abuolaim*, Mahmoud Afifi*, and Michael S. Brown
ICCP 2020
York University
A symmetry property of dual-pixel kernels for unsupervised depth estimation
* Equal contribution
Paper | Code & Dataset | Talk
Atima Lui, Nyalia Lui, Mahmoud Afifi, and Ariadne Bazigos
US Patent 2020
My Nudest Inc
A system for analyzing user input, combining user's image(s) and query responses to provide tailored color outputs. Through color correction and comparison to predetermined color identifiers, it delivers accurate results and product recommendations.
Majed El Helou, Ruofan Zhou, Sabine Süsstrunk, Radu Timofte, Mahmoud Afifi, et al.,
ECCV workshops 2020
York University
Runner-Up Award overall tracks
As an intermediate stage, producing a uniformly-lit white-balanced image could help to eventually produce high-quality relit images.
arXiv | Code | Certificate
Mahmoud Afifi and Michael S. Brown
CIC 2020 (Oral Presentation)
York University
A simple method to link the nonlinear white-balance correction functions, introduced in our CVPR'19 work, to the user's selected colors to allow interactive white-balance manipulation
arXiv | Code | Presentation
Hoang Le, Mahmoud Afifi, and Michael S. Brown
CIC 2020 (Oral Presentation)
York University
Having additional wide-gamut metadata, available during color space conversion, greatly assists in constructing a locally weighted color mapping function to convert between color gamuts.
Mahmoud Afifi and Michael S. Brown
ICCV 2019
25% acceptance rateYork University
Deep learning models can be fooled by white-balance errors and their accuracy can be improved by augmented images with different white-balance settings.
Paper | Supp. Materials | arXiv | Project Page | Code | Colab
Mahmoud Afifi, Brian Price, Scott Cohen, and Michael S. Brown
CVPR 2019
25.2% acceptance rateYork University in collaboration with Adobe Research
The first work to directly address the problem of incorrectly white-balanced images; requires a small memory overhead and it is fast.
Paper | Project Page | Supp. Materials | Demo | Video | Code | Dataset | Adobe Research Post | Patent
Mahmoud Afifi, Brian Price, Scott Cohen, and Michael S. Brown.
Eurographics 2019 (Short Papers)
York University in collaboration with Adobe Research
A fully automated image recoloring without the need for target/reference images
Paper | Project Page | External Link | Code | Supp. Materials | Presentation | Fast-Forward Video | Adobe Research Post
Mahmoud Afifi and Michael S. Brown
BMVC 2019 (Oral Presentation)
28% acceptance rate | 5% oral presentation acceptance rateYork University
Learning a new canonical space in an unsupervised manner allows us to train a single deep model on multiple camera sensors and perform accurate illuminant estimation for images captured by new unseen camera sensors in the inference phase.
Paper | Project Page | Supp. Materials | arxiv | Code | Presentation | Talk | Patent
Mahmoud Afifi, Abhijith Punnappurath, Abdelrahman Abdelhamed, Hakki Can Karaimer, Abdullah Abuolaim, and Michael S. Brown
CIC 2019 (Oral Presentation)
Best paper award
York University
With a small modification to existing camera ISPs, we can achieve accurate post-capture white balance editing by embedding a set of mapping coefficients in the JPEG metadata.
Paper | Project Page | Code | Presentation | Patent Application
Mahmoud Afifi, Abhijith Punnappurath, Graham Finlayson, and Michael S. Brown
JOSA A 2019
Impact factor: 1.4 (2023)York University in collaboration with University of East Anglia
A locally adaptive bias correction technique for illuminant estimation
Abdullah Sawas*, Abdullah Abuolaim*, Mahmoud Afifi, and Manos Papagelis
MDM 2018
Best paper award
York University
Efficient discovery of evolving groups of pedestrians; a new group pattern is introduced in the journal version.
* Equal contribution
Mahmoud Afifi and Abdelrahman Abdelhamed
JVCI 2019
Impact factor: 2.6 (2023)Assiut University
Gender classification can be improved using different facial features; our finding is validated by a user study.
Mahmoud Afifi
MTA 2019
Impact factor: 3.0 (2023)Assiut University
Hand images can efficacy be used for gender recognition and biometric identification; a large dataset of hand images enables us to train our two-stream deep model.
Khaled F. Hussain, Mahmoud Afifi, Ghada Moussa
ITS 2018
Impact factor: 7.9 (2023)Assiut University
In generic vehicle classification tasks, deep learning models tend to not rely on color information and filter out unnecessary details information in high-resolution images.
Mahmoud Afifi and Khaled F. Hussain
CVM 2016
Impact factor: 17.3 (2023)Assiut University
Bleeding artifacts caused by Poisson image editing can be reduced by a simple two-stage blending approach.
Paper | Project Page | Code | Video
Conference version: Paper | Project Page | Code | Video
Mahmoud Afifi, Khaled F. Hussain, Hosny M. Ibrahim, and Nagwa M. Omar
ISPACS 2015
Assiut University
In many scenarios, image registration and blending can help to get a fast video completion.
Honors
Dissertation Award
CS-Can|Info-Can Canadian Computer Science Distinguished Dissertation Award, 2021 | Lassonde post
CIPPRS John Barron Doctoral Dissertation Award, 2021 | Lassonde post
Nominated by EECS for the Best Doctoral Dissertation Prize at York University, 2021
Best Paper Award
Outstanding Reviewer
European Conference on Computer Vision, 2024 (ECCV'24)
IEEE/CVF Conference on Computer Vision and Pattern Recognition, 2024 (CVPR'24)
IEEE/CVF International Conference on Computer Vision, 2021 (ICCV'21)
IEEE/CVF Conference on Computer Vision and Pattern Recognition, 2020 (CVPR'20)
Honourable Mention at British Machine Vision Conference, 2019 (BMVC'19)
Challenges
Runner-Up Award overall tracks in AIM 2020 Challenge on Scene Relighting and Illumination Estimation at ECCV'20
Best Short CG Film in the Fourth Forum of Egyptian Faculties of Computer and Information Science, 2010
Others
Professional Services
Google Advocate for the African Computer Vision Summer School (ACVSS) in Kenya, 2024
Program Committee Member:
AIM: Advances in Image Manipulation workshop in conjunction with ECCV 2024
NTIRE: New Trends in Image Restoration and Enhancement workshop and challenges in conjunction with CVPR 2024
NTIRE: New Trends in Image Restoration and Enhancement workshop and challenges in conjunction with CVPR 2023
NTIRE: New Trends in Image Restoration and Enhancement workshop and challenges in conjunction with CVPR 2022 | Apple post
NTIRE: New Trends in Image Restoration and Enhancement workshop and challenges in conjunction with CVPR 2020
Student Representative at Tenure & Promotion Adjudicating Committee, EECS, York University, 2020
Reviewer:
Conferences: ECCV'24, CVPR'24, ACCV'24, LIM'24, SIGGRAPH Asia'23, ICCV'23, CVPR'23, SIGGRAPH Asia'22, CVPR'22, WACV'22, SIGGRAPH Asia'21, SIGGRAPH'21, ICCV'21, CVPR'21, BMVC'21, WACV'21, MASCOTS'21, CVPR'20, WACV'20, ACCV'20, MASCOTS'20, CIC28, CRV'20, WACV'19, CIC27, BMVC'19, BMVC'18
Journals: T-PAMI, T-IP, IJCV, T-CI, T-MM, CVM, VTM, T-ITS, T-CSVT, T-HMS, T-MECH, T-CE, Neurocomputing, IEEE Access, TOMM, TVCJ, MTAP, COL, Displays, JVCI, MULT, MVAP, SIVP, JRTIP, IET IP, IET CV, IET SP, IET EL, SPIE JEI, CIN, JHE, OPENCS
Vice-Chair: ACM Assiut Student Chapter