48 research outputs found
Crowdsourcing in Computer Vision
Computer vision systems require large amounts of manually annotated data to
properly learn challenging visual concepts. Crowdsourcing platforms offer an
inexpensive method to capture human knowledge and understanding, for a vast
number of visual perception tasks. In this survey, we describe the types of
annotations computer vision researchers have collected using crowdsourcing, and
how they have ensured that this data is of high quality while annotation effort
is minimized. We begin by discussing data collection on both classic (e.g.,
object recognition) and recent (e.g., visual story-telling) vision tasks. We
then summarize key design decisions for creating effective data collection
interfaces and workflows, and present strategies for intelligently selecting
the most important data instances to annotate. Finally, we conclude with some
thoughts on the future of crowdsourcing in computer vision.Comment: A 69-page meta review of the field, Foundations and Trends in
Computer Graphics and Vision, 201
Improving Semantic Embedding Consistency by Metric Learning for Zero-Shot Classification
This paper addresses the task of zero-shot image classification. The key
contribution of the proposed approach is to control the semantic embedding of
images -- one of the main ingredients of zero-shot learning -- by formulating
it as a metric learning problem. The optimized empirical criterion associates
two types of sub-task constraints: metric discriminating capacity and accurate
attribute prediction. This results in a novel expression of zero-shot learning
not requiring the notion of class in the training phase: only pairs of
image/attributes, augmented with a consistency indicator, are given as ground
truth. At test time, the learned model can predict the consistency of a test
image with a given set of attributes , allowing flexible ways to produce
recognition inferences. Despite its simplicity, the proposed approach gives
state-of-the-art results on four challenging datasets used for zero-shot
recognition evaluation.Comment: in ECCV 2016, Oct 2016, amsterdam, Netherlands. 201
A Crowdsourcing Procedure for the Discovery of Non-Obvious Attributes of Social Image
Research on mid-level image representations has conventionally concentrated
relatively obvious attributes and overlooked non-obvious attributes, i.e.,
characteristics that are not readily observable when images are viewed
independently of their context or function. Non-obvious attributes are not
necessarily easily nameable, but nonetheless they play a systematic role in
people`s interpretation of images. Clusters of related non-obvious attributes,
called interpretation dimensions, emerge when people are asked to compare
images, and provide important insight on aspects of social images that are
considered relevant. In contrast to aesthetic or affective approaches to image
analysis, non-obvious attributes are not related to the personal perspective of
the viewer. Instead, they encode a conventional understanding of the world,
which is tacit, rather than explicitly expressed. This paper introduces a
procedure for discovering non-obvious attributes using crowdsourcing. We
discuss this procedure using a concrete example of a crowdsourcing task on
Amazon Mechanical Turk carried out in the domain of fashion. An analysis
comparing discovered non-obvious attributes with user tags demonstrated the
added value delivered by our procedure.Comment: 6 pages, 3 figures, Extended version of paper to appear in CrowdMM
2014: International ACM Workshop on Crowdsourcing for Multimedi
Learning Multimodal Latent Attributes
Abstract—The rapid development of social media sharing has created a huge demand for automatic media classification and annotation techniques. Attribute learning has emerged as a promising paradigm for bridging the semantic gap and addressing data sparsity via transferring attribute knowledge in object recognition and relatively simple action classification. In this paper, we address the task of attribute learning for understanding multimedia data with sparse and incomplete labels. In particular we focus on videos of social group activities, which are particularly challenging and topical examples of this task because of their multi-modal content and complex and unstructured nature relative to the density of annotations. To solve this problem, we (1) introduce a concept of semi-latent attribute space, expressing user-defined and latent attributes in a unified framework, and (2) propose a novel scalable probabilistic topic model for learning multi-modal semi-latent attributes, which dramatically reduces requirements for an exhaustive accurate attribute ontology and expensive annotation effort. We show that our framework is able to exploit latent attributes to outperform contemporary approaches for addressing a variety of realistic multimedia sparse data learning tasks including: multi-task learning, learning with label noise, N-shot transfer learning and importantly zero-shot learning