Query by Example
==Timothy J. Hazen et al. “Query-by-example spoken term detection using phonetic posteriorgram templates” IEEE Automatic Speech Recognition and Understanding Workshop (2009).==
思想
- 用声学模型输出后验直方图(t帧*分类数)作为匹配的对象
- 模板匹配,用DTW

分数归一化($\frac{1}{m}$),使得路径分数从query frame获得的贡献相同(不管路径吸收了多少test frame)
- 多个query的情况(多个命令词),不用知道识别了哪个命令词,只要知道有没有识别命令词即可。两种方法:
- 1.把多个query模板combine成一个;
- 2.把所有的query模板都拿去于test匹配,把匹配分数求和取平均:

==Chen Guoguo,Parada C, Sainath T N, et al. Query-by-example keyword spotting using longshort-term memory networks[C]. international conference on acoustics, speech,and signal processing, 2015: 5236-5240.==
思想
- 嵌入学习embedding的样例检索
- 自定义唤醒词