← Back to the Ubunatic Library

VDDA Live

Visualization-driven data aggregation, running entirely in your browser: an embedded DuckDB (WebAssembly) executes the actual M4 query from the VLDB 2014 paper against data you record — and proves the reduced chart is pixel-identical.

This demo needs to be served over HTTP (WebAssembly workers do not load from file://). Run make serve-web or open it on the website.

1Record a series — press and hold, you are the sensor

Hold the button to record a time series: time sweeps forward at a fixed sample rate while your pointer drives the signal — its height sets the level, and moving in any direction shakes the sensor into noise bursts. Release to load the recording into DuckDB — it gets upsampled with sensor noise to the row count below. No mouse handy?

2Reduce — rewrite the query, not the client

Underlying rows

Chart width (pixels)

Aggregation technique

Loading DuckDB…

3Compare — baseline vs. reduced, pixel by pixel

Baseline — all rows, rasterized

Reduced — rows selected by the rewritten query

Pixel errors — black = false pixels, white = missing pixels

—

underlying rows

—

rows after reduction

—

data reduction

—

query time (ms)

—

pixel errors