Saved in:
Bibliographic Details
Main Authors: Lee, Seokhyun, Kim, Jaeho, Oh, Changjun, van der Schaar, Mihaela, Lee, Changhee
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2605.01418
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913083557937152
author Lee, Seokhyun
Kim, Jaeho
Oh, Changjun
van der Schaar, Mihaela
Lee, Changhee
author_facet Lee, Seokhyun
Kim, Jaeho
Oh, Changjun
van der Schaar, Mihaela
Lee, Changhee
contents Time-series generative models often lack control over temporal granularity, forcing users to accept whatever granularity the model produces. To enable truly user-driven generation, we introduce TimeTok, a unified framework for Granularity-Controllable Time-Series Generation (GC-TSG), which generates time series at any target granularity from any coarser input (e.g., rough sketches) or from scratch. At the core of TimeTok is a hierarchical tokenization strategy that maps time series into an ordered sequence of tokens, from coarse to fine temporal granularity. Our autoregressive generation process operates across these granularity levels, producing token blocks that are decoded back into continuous time series. This design naturally enables GC-TSG - including standard generation - within a single framework, where controlling the number of token blocks provides explicit control over output detail. Experiments show that TimeTok excels at GC-TSG tasks while achieving state-of-the-art performance in standard generation. Furthermore, we showcase TimeTok's potential as a foundational tokenizer by training on multiple datasets with heterogeneous temporal granularities, verifying strong transferability that consistently outperforms models trained on individual datasets. To our knowledge, this is the first unified framework that covers the full generative spectrum for time series, offering a valuable foundation for models that benefit from diverse temporal granularities.
format Preprint
id arxiv_https___arxiv_org_abs_2605_01418
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle TimeTok: Granularity-Controllable Time-Series Generation via Hierarchical Tokenization
Lee, Seokhyun
Kim, Jaeho
Oh, Changjun
van der Schaar, Mihaela
Lee, Changhee
Artificial Intelligence
Time-series generative models often lack control over temporal granularity, forcing users to accept whatever granularity the model produces. To enable truly user-driven generation, we introduce TimeTok, a unified framework for Granularity-Controllable Time-Series Generation (GC-TSG), which generates time series at any target granularity from any coarser input (e.g., rough sketches) or from scratch. At the core of TimeTok is a hierarchical tokenization strategy that maps time series into an ordered sequence of tokens, from coarse to fine temporal granularity. Our autoregressive generation process operates across these granularity levels, producing token blocks that are decoded back into continuous time series. This design naturally enables GC-TSG - including standard generation - within a single framework, where controlling the number of token blocks provides explicit control over output detail. Experiments show that TimeTok excels at GC-TSG tasks while achieving state-of-the-art performance in standard generation. Furthermore, we showcase TimeTok's potential as a foundational tokenizer by training on multiple datasets with heterogeneous temporal granularities, verifying strong transferability that consistently outperforms models trained on individual datasets. To our knowledge, this is the first unified framework that covers the full generative spectrum for time series, offering a valuable foundation for models that benefit from diverse temporal granularities.
title TimeTok: Granularity-Controllable Time-Series Generation via Hierarchical Tokenization
topic Artificial Intelligence
url https://arxiv.org/abs/2605.01418