Kindly monks,

I have a large swathe of color information about a photo collection in RGB format. Given a range of RGB values, I would like to retrieve photos containing those colors.

Right now, all this data is in a database table, with four columns: a red value, a green value, a blue value, and a photo ID. Lookups now occur in some sort of fashion like: select photo_id from colors where r in (12,13,14,15) and g in (78,79,80,81) and b in (23,24,25,26)

This takes a long time.

I would like to put all this information in a giant in-memory data structure for super-fast lookups. But just what sort of data structure I need escapes my current spiritual wisdom.

A brute force approach of pre-compiling all possible RGB combinations and the photos they correspond to is possible, but I'm hoping a lone monk out there might know of a more elegant approach.

Humbly,
danmcc

In reply to multi-dimensional range lookup by danmcc

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