Title
Learning to Associate Words and Images Using a Large-Scale Graph
Abstract
We develop an approach for unsupervised learning of associations between co-occurring perceptual events using a large graph. We applied this approach to successfully solve the image captcha of China's railroad system. The approach is based on the principle of suspicious coincidence, originally proposed by Barlow [1], who argued that the brain builds a statistical model of the world by learning associations between events that repeatedly co-occur. In this particular problem, a user is presented with a deformed picture of a Chinese phrase and eight low-resolution images. They must quickly select the relevant images in order to purchase their train tickets. This problem presents several challenges: (1) the teaching labels for both the Chinese phrases and the images were not available for supervised learning, (2) no pre-trained deep convolutional neural networks are available for recognizing these Chinese phrases or the presented images, and (3) each captcha must be solved within a few seconds. We collected 2.6 million captchas, with 2.6 million deformed Chinese phrases and over 21 million images. From these data, we constructed an association graph, composed of over 6 million vertices, and linked these vertices based on co-occurrence information and feature similarity between pairs of images. We then trained a deep convolutional neural network to learn a projection of the Chinese phrases onto a 230- dimensional latent space. Using label propagation, we computed the likelihood of each of the eight images conditioned on the latent space projection of the deformed phrase for each captcha. The resulting system solved captchas with 77% accuracy in 2 seconds on average. Our work, in answering this practical challenge, illustrates the power of this class of unsupervised association learning techniques, which may be related to the brain's general strategy for associating language stimuli with visual objects on the principle of suspicious coincidence.
Year
DOI
Venue
2017
10.1109/CRV.2017.52
2017 14th Conference on Computer and Robot Vision (CRV)
Keywords
DocType
Volume
unsupervised learning,captcha,associative learning,label propagation,suspicious coincidence
Conference
abs/1705.07768
ISBN
Citations 
PageRank 
978-1-5386-2819-5
0
0.34
References 
Authors
17
4
Name
Order
Citations
PageRank
Heqing Ya100.34
Haonan Sun220.69
Jeffrey Helt300.34
Tai Sing Lee479488.73