@INPROCEEDINGS{fuga2021product, author={Nakamura, Fuga and Harakawa, Ryosuke and Iwahashi, Masahiro}, booktitle={2021 Asia-Pacific Signal and Information Processing Association Annual Summit and Conference (APSIPA ASC)}, title={Product Quantization to Reduce Entropy of Labels for Fast and Accurate Image Retrieval}, year={2021}, volume={}, number={}, pages={1536-1540}, doi={} }