Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Action Recognition in Video Using Sparse Coding and Relative Features   This work presents an approach to category-based action recognition in video
using sparse coding techniques. The proposed approach includes two main
contributions: i) A new method to handle intra-class variations by decomposing
each video into a reduced set of representative atomic action acts or
key-sequences, and ii) A new video descriptor, ITRA: Inter-Temporal Relational
Act Descriptor, that exploits the power of comparative reasoning to capture
relative similarity relations among key-sequences. In terms of the method to
obtain key-sequences, we introduce a loss function that, for each video, leads
to the identification of a sparse set of representative key-frames capturing
both, relevant particularities arising in the input video, as well as relevant
generalities arising in the complete class collection. In terms of the method
to obtain the ITRA descriptor, we introduce a novel scheme to quantify relative
intra and inter-class similarities among local temporal patterns arising in the
videos. The resulting ITRA descriptor demonstrates to be highly effective to
discriminate among action categories. As a result, the proposed approach
reaches remarkable action recognition performance on several popular benchmark
datasets, outperforming alternative state-of-the-art techniques by a large
margin.

17
The categories of this paper are: q-fin
7
The categories of this paper are: hep-th
26
The categories of this paper are: bayes-an
21
The categories of this paper are: adap-org
22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
0
The categories of this paper are: hep-ph
27
The categories of this paper are: comp-gas
4
The categories of this paper are: cond-mat
29
The categories of this paper are: funct-an
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
25
The categories of this paper are: patt-sol
10
The categories of this paper are: q-bio
12
The categories of this paper are: nucl-th