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+# AISHELL-2
+
+AISHELL-2 is by far the largest free speech corpus available for Mandarin ASR research.
+## 1. DATA
+### Training data
+* 1000 hours of speech data (around 1 million utterances)
+* 1991 speakers (845 male and 1146 female)
+* clean recording environment (studio or quiet living room)
+* read speech
+* reading prompts from various domain: entertainment, finance, technology, sports, control command, place of interest etc.
+* near field recording via 3 parallel channels (iOS, Android, Microphone).
+* iOS data is free for non-commercial research and education use (e.g. universities and non-commercial institutes)
+
+### Evaluation data:
+Currently we release AISHELL2-2018A-EVAL, containing:
+* dev: 2500 utterances from 5 speakers
+* test: 5000 utterances from 10 speakers
+
+Both sets are available across the three channel conditions.
+
+One of interest can download the sets from [here](http://www.aishelltech.com/aishell_eval). Note that we may update and release other evaluation sets on the website later, targeting on different applications and senarios.
+
+## 2. RECIPE
+Based on Kaldi standard system, AISHELL-2 provides a self-contained Mandarin ASR recipe, with:
+* a word segmentation module, which is a must-have component for Chinese ASR systems
+* an open-sourced Mandarin lexicon (DaCiDian, open-sourced at [here](https://github.com/aishell-foundation/DaCiDian))
+* Simplified GMM training & alignment generating recipe (we stopped at speaker independent stage)
+* LFMMI TDNN training and decoding recipe
+
+# REFERENCE
+We released a [paper on Arxiv](https://arxiv.org/abs/1808.10583) on a more detailed description about the corpus with some preliminary resulting numbers. If one would like to use AISHELL-2 in experiments, please cite the paper as below:
+```
+@ARTICLE{aishell2,
+   author = {{Du}, J. and {Na}, X. and {Liu}, X. and {Bu}, H.},
+   title = "{AISHELL-2: Transforming Mandarin ASR Research Into Industrial Scale}",
+   journal = {ArXiv},
+   eprint = {1808.10583},
+   primaryClass = "cs.CL",
+   year = 2018,
+   month = Aug,
+}
+```
+
+# APPLY FOR DATA/CONTACT
+AISHELL foundation is a non-profit online organization, with members from speech industry and research institutes.
+
+We hope AISHELL-2 corpus and recipe could be beneficial to the entire speech community.
+
+Depends on your location and internet speed, we distribute the corpus in two ways:
+* hard-disk delivery
+* cloud-disk downloading
+
+To apply for AISHELL-2 corpus for free, you need to fill in a very simple application form, confirming that:
+* university department / educational institute information has been fully provided
+* only for non-commercial research / education use
+
+AISHELL-foundation covers all data distribution fees (including the corpus, hard-disk cost etc)
+
+Data re-distribution inside your university department is OK for convenience. However, users are not supposed to re-distribute the data to other universities or educational institutes.
+
+To get the application form, or you come across any problem with the recipe, contact us via:
+
+[email protected]
+