馃憢 Hi, all!

I am Elliot Shichao Song, a PhD candidate. My current research focuses on foundation models. I blog about my research and life.
Cyanotype of the works, a phone, windows, a ring, a bell curve and a grid, joined by a thread that runs on

Things I've Made

Products and small things I have made, all in one place.

 路 4 min 路 740 words 路 Elliot Shichao Song
An AI-coordinated image hub (generated with [GPT Image 2.6 Sunburst](https://openai.com/index/introducing-images-2-6/))

Efficient Large-Scale Crawling with an AI Agent: 3 Days, $175, 3 Billion Original Images

Downloading the originals behind 2.98 billion image URLs in OmniCorpus-CW, I left almost all operations to an AI agent: patrols, rate tuning, creating and deleting machines, incident handling and billing. I only made the decisions. In 79 hours it saved 99.6% of the images, 744 TB, for about $175 in machines.

 路 8 min 路 1545 words 路 Elliot Shichao Song
A caption passes through the judge and splits three ways: correct, omission and hallucination (generated with [ChatGPT Images](https://chatgpt.com/))

CaptionExam: A Challenging QA Benchmark for Captioners

On CaptionExam, even GPT-6 Astra only just passes at describing images, with a score of 61.2%.

 路 10 min 路 2045 words 路 Elliot Shichao Song
Semantic islands: retrieving similar samples from a sea of images (generated with [ChatGPT Images](https://chatgpt.com/))

A Billion-Scale Retrieval System for Text-to-Image Training Data

Training a text-to-image model from scratch means finding, inspecting and filtering samples across billions of image鈥搕ext pairs. Using a retrieval system over 1.4B samples as an example, this post covers data storage and management, distributed embedding extraction, building and querying an IVF-PQ index, and online retrieval and cluster browsing.

 路 19 min 路 3948 words 路 Elliot Shichao Song
Reinforcement Learning illustration (by [Google Gemini](https://gemini.google.com/))

Fully Annotated Guide to "A (Long) Peek into Reinforcement Learning"

This is a fully annotated guide to Lilian Weng鈥檚 post A (Long) Peek into Reinforcement Learning.

 路 Updated:  路 45 min 路 9392 words 路 Shichao Song