This document describes CLEAR, a fully user-side image search system developed by Ryoma Sato at Kyoto University. CLEAR allows users to build and publish their own image search engines without backend servers by formulating image search as a multi-armed bandit problem and implementing the system using only JavaScript on the client-side. This overcomes limitations of traditional search engines which require extensive resources to operate. CLEAR demonstrates that ordinary users can now develop customized image search tools.

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KYOTO UNIVERSITY
CLEAR: A Fully User-side Image Search System
Ryoma Sato

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Traditional Services
Service
Develop & Operate
Official Developer
Serve
Twitter

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Problem: each user wants different services
A’s ideal service
Bs’ ideal services
C’s ideal service
D’s ideal service
gap
Actual Service

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User-side systems realize users’ ideals
A’s ideal service
Bs’ ideal services
C’s ideal service
D’s ideal service
Actual Service
User-side systems fill this
gap on the user’s side

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Challenge: users cannot access to the database

Standard IR sysmtes
are implemented by Engineers of
Twitter, who have complete
access to the database.

User-side IR systems
are implemented by users, who don’t have direct access to the database.
Twitter Inc.
Database
Twitter Engineer
IR system
SQL
ANN
Twitter Inc.
Database
User
SQL
Search Query
API

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Flickr provides text search only, no image-based
↑put text here to search for images
Flickr supports tag
and text-based
searches, but no
image-based search
We want to find
images with similar
atmosphere,
similar composition,
and similar colors,
based on images
at hand

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Suppose we have a score function

Suppose we have a function that receives an image
and returns a scalar score

Ex) The more similar a image is to the image at hand,
the higher the score.

Similarity can be calculated based on composition,
color, etc. It is up to the user to decide which one to
use (depending on what the user wants to do).
0.882

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Maximize the score function at hand fron Flickr

Suppose we have a function that receives an image
and returns a scalar score

Problem setup: retrieve (in real time) the image with
the maximum score from all Flickr images when the
score function is passed by the user.
0.882

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Naive methods are intractable

Method 1: A very naive method is to crawl a large
number of images from Flickr, evaluate each one's
score, and return the image with the highest score
→ High communication cost, not finish in real time

Method 2: Pre-crawl and build an index
→ Storage and server costs are high, and is intractable
for an ordinary user.

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Architecture of CLEAR

CLEAR searches images on the fly
CLEAR runs on the frontend
No indices or crawling
No backend servers

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Formulate as a multi-armed bandit problem

Regard the search query as an arm and formulate the
problem as a multi-armed bandit problem
q = dog q = cat q = Persian cat q = goldfish
0.725
Issue a query
reward
...
Score function f

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Demo Video
Demo: https://clear.joisino.net/

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Develop and publish your own search engine

Contribution: An ordinary user realizes a new search
engine for the existing service.

You can easily develop your own search engine.
↔ Traditionally, building search engines requires
a lot of storage, computational, and network
resources.

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CLEAR is general
CLEAR
score function A
content-based
user specifies
the function

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CLEAR is general
CLEAR
score function B
hue-based
you can use
different ones

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CLEAR is general
CLEAR
score function B
hue-based
you can change
the target service

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CLEAR is general
CLEAR
score function B
hue-based
you can change
the target service

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Develop and publish your own search engine

CLEAR is implemented fully on the client’s side
(with JavaScript)

No back-end servers
→ You can realize your own search engine by rewriting
the score function and opening it in a browser.
→ Deployment is easy
You can deploy in on GitHub Pages or Amazon S3.
→ The more people create and publish their own
search systems, the more options there are, and the
easier it will be to find a favorite search system.
↔ Only Flickr official ones and a few voluntary ones.

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Summary: First fully user-side image search

CLEAR is the first practical implementation of
fully user-side image search.

The system is implemented completely on the client-
side (Javascript).

You can build and publish your own search engine.
Code: https://github.com/joisino/clear
Demo: https://clear.joisino.net/
Fork the repository and
build your own search engine!