Compressed Histogram of Gradients: A Low Bitrate Descriptor

For many mobile visual search applications, a query photo is taken by a mobile device and compared against a database on a remote server. The size of the data sent over the network needs to be as small as possible to reduce latency and improve user experience. We have studied descriptor compression techniques and shown that compressed descriptors can reduce query latency significantly in mobile image retrieval systems. Here, we make publicly available a Linux binary of a new low bitrate descriptor called Compressed Histogram of Gradients (CHoG) [1-3] with location coding [4].

References:
[1] V. Chandrasekhar, G. Takacs, D. Chen, S. Tsai, Y. Reznik, R. Grzeszczuk, and B. Girod, "Compressed histogram of gradients: a low bitrate descriptor", International Journal on Computer Vision, Vol. 94, No. 5, May 2011.
[2] V. Chandrasekhar, Y. Reznik, G. Takacs, D. Chen, S. Tsai, R. Grzeszczuk, and B. Girod, "Quantization schemes for low bitrate compressed histogram of gradients descriptors", IEEE International Workshop on Mobile Vision, June 2010.
[3] V. Chandrasekhar, G. Takacs, D. Chen, S. Tsai, R. Grzeszczuk, and B. Girod, "CHoG: compressed histogram of gradients", IEEE International Conference on Computer Vision and Pattern Recognition, June 2009.
[4] S. Tsai, D. Chen, G. Takacs, V. Chandrasekhar, J. P. Singh, and B. Girod, "Location coding for mobile image retrieval", International Mobile Multimedia Communications Conference, September 2009.
[5] B. Girod, V. Chandrasekhar, R. Grzeszczuk, Y. A. Reznik, "Mobile Visual Search: Architectures, Technologies, and the Emerging MPEG Standard", IEEE MultiMedia, vol. 18, no. 3, pp. 86-94, July-September 2011.