File : README



		                AISHELL-2 Speech Data

			北京希尔贝壳科技有限公司
      	            	    Beijing Shell Shell Technology Co.,Ltd
			           03/10/2018

1. AISHELL-2 Speech Data

		- Sampling Rate : 	16kHz
		- Sample Format : 	16bit
		- Environment :		Indoor
		- Speech Data Type : 	PCM
		- Channel Number : 	1
		- Recording Equipment : 	iOS
		- Time : 	1000 hours of speech data (around 1 million utterances)
		- Speaker : 	1991 speakers (845 male and 1146 female)


2. 数据目录结构
│  AISHELL2-Data-Specification .docx			                （Corpus Information）
│  README.txt			                                              (readme）
│  ChangeLog			                                                      	  （Change Information）
└─ data				                          	                （Data File）
	│├─wav.list                                                                               （Audio list）
	│├─trans.txt                                                                             （Transcript Content）
	│├─spk_info.txt                                                                       （Speaker Information）
	│├─wav                                                                                     （Audio Data File）
	│├─D2166						  （Speaker ID File）
        	││  ││      ID2166W0001.wav			                （Audio）

3. Evaluation Data:
		Currently we open-sourced AISHELL2-2018A-EVAL
		-  dev: 2500 utterances from 5 speaker
		-  test: 5000 utterances from 10 speakers
		You can download above evaluation set from: https://www.aishelltech.com/aishell_2018_eval

4. RECIPE
		Based on Kaldi standard system, AISHELL-2 provides a self-contained Mandarin ASR recipe
		-  a word segmentation module, which is a must-have component for Chinese ASR systems
		-  an open-sourced Mandarin lexicon(DaCiDian)
		-  a simplified GMM training recipe
		-  80-dim FBank without pitch as NN input feature
		-  slightly different data augmentation setup(tempo perturbation, max-volume perturbation)
		-  acoustic channel adaptation recipe(AM fine-tuning)
		-  a real-time streaming ASR demo via laptop microphone (tested on MacOS)
		You can download recipe set from: http://www.aishelltech.com/aishell_2