How to Sample High Quality 3D Fractals for Action Recognition Pre-Training?

TL;DR

This paper introduces a fast and diverse method for generating 3D fractals using Targeted Smart Filtering, improving pre-training for action recognition models with synthetic data.

Contribution

It proposes a novel, efficient fractal generation technique that enhances diversity and speed, benefiting synthetic data pre-training for action recognition.

Findings

Targeted Smart Filtering is 100 times faster than traditional methods.

The method produces more diverse and effective 3D fractals for pre-training.

Improved downstream action recognition performance using generated fractals.

Abstract

Synthetic datasets are being recognized in the deep learning realm as a valuable alternative to exhaustively labeled real data. One such synthetic data generation method is Formula Driven Supervised Learning (FDSL), which can provide an infinite number of perfectly labeled data through a formula driven approach, such as fractals or contours. FDSL does not have common drawbacks like manual labor, privacy and other ethical concerns. In this work we generate 3D fractals using 3D Iterated Function Systems (IFS) for pre-training an action recognition model. The fractals are temporally transformed to form a video that is used as a pre-training dataset for downstream task of action recognition. We find that standard methods of generating fractals are slow and produce degenerate 3D fractals. Therefore, we systematically explore alternative ways of generating fractals and finds that overly-restrictive approaches, while generating aesthetically pleasing fractals, are detrimental for downstream task performance. We propose a novel method, Targeted Smart Filtering, to address both the generation speed and fractal diversity issue. The method reports roughly 100 times faster sampling speed and achieves superior downstream performance against other 3D fractal filtering methods.