@article {IOPORT.06023420,
    author       = {Chandrasekhar, Vijay and Takacs, Gabriel and Chen, David M. and Tsai, Sam S. and Reznik, Yuriy},
    title        = {Compressed histogram of gradients: a low-bitrate descriptor.},
    year         = {2012},
    journal      = {International Journal of Computer Vision},
    volume       = {96},
    number       = {3},
    issn         = {0920-5691},
    pages        = {384-399},
    publisher    = {Springer, New York, NY},
    doi          = {10.1007/s11263-011-0453-z},
    abstract     = {Summary: Establishing visual correspondences is an essential component of many computer vision problems, which is often done with local feature-descriptors. Transmission and storage of these descriptors are of critical importance in the context of mobile visual search applications. We propose a framework for computing low bit-rate feature descriptors with a $20\times $ reduction in bit rate compared to state-of-the-art descriptors. The framework offers low complexity and has significant speed-up in the matching stage. We show how to efficiently compute distances between descriptors in the compressed domain eliminating the need for decoding. We perform a comprehensive performance comparison with SIFT, SURF, BRIEF, MPEG-7 image signatures and other low bit-rate descriptors and show that our proposed CHoG descriptor outperforms existing schemes significantly over a wide range of bitrates. We implement the descriptor in a mobile image retrieval system and for a database of 1 million CD, DVD and book covers, we achieve 96\% retrieval accuracy using only 4 KB of data per query image.},
    identifier   = {06023420},
}