System and method for automatic language model selection

1. A computer-implemented method of generating a transcript of an audio input, the method comprising:

generating a phonetic lattice by decoding the audio input;

producing a transcription based on the phonetic lattice and based on a first language model;

associating words identified in the transcription with a certainty value calculated for each identified word;

including words associated with a certainty value higher than a first threshold value in a combined index;

selecting, from a plurality of language models and based on the combined index, a second language model; and

generating a second transcription of the audio input based on the phonetic lattice and using the second language model.

2. The method of claim 1 , wherein the first language model is a general model and the second language model is a specific language model.

3. The method of claim 1 , comprising:

combining at least two sub-words identified in the transcription to produce a word and including the produced word in the combined index.

4. The method of claim 1 , comprising identifying key phrases in the transcription and including the key phrases in the combined index.

5. The method of claim 1 , comprising, selecting the second language model based on calculating a plurality of match values by relating a respective plurality of specific language models to the combined index and selecting the specific language model associated with the highest match value.

6. The method of claim 1 , comprising:

associating sub-words identified in the transcription with a certainty value calculated for each identified sub-word;

identifying a sequence of sub-words associated with a certainty value higher than a second threshold value;

producing a word based on the identified sequence of sub-words; and

including the produced word in the combined index.

7. A computer-implemented method of generating a transcript of an audio input, the method comprising:

producing a first transcription of the audio input using a first language model;

associating words identified in the first transcription with a certainty value calculated for each identified word;

including words associated with a certainty value higher than a first threshold value in a structured data;

selecting, from a plurality of language models, a second language model by matching the plurality of language models with the structured data; and

producing a second transcription of the audio input using the second language model.

8. An article comprising a non-transitory computer-readable storage medium, having stored thereon instructions that, when executed by a controller, cause the controller to:

generate a phonetic lattice by decoding the audio input;

produce a transcription based on the phonetic lattice and based on a first language model;

associate words identified in the transcription with a certainty value calculated for each identified word;

include words associated with a certainty value higher than a first threshold value in a combined index;

select, from a plurality of language models and based on the combined index, a second language model; and

use the second language model and the phonetic lattice to generate a second transcript of the audio input.

9. The article of claim 8 , wherein the first language model is a general model and the second language model is a specific language model.

10. The article of claim 8 , wherein the instructions when executed further result in:

combining at least two sub-words identified in the transcription to produce a word and including the produced word in the combined index.

11. The article of claim 8 , wherein the instructions when executed further result in identifying key phrases in the transcription and including the key phrases in the combined index.

12. The article of claim 8 , wherein the instructions when executed further result in selecting the second language model based on calculating a plurality of match values by relating a respective plurality of specific language models to the combined index and selecting the specific language model associated with the highest match value.

13. The article of claim 8 , wherein the instructions when executed further result in:

associating sub-words identified in the transcription with a certainty value calculated for each identified sub-word;

identifying a sequence of sub-words associated with a certainty value higher than a second threshold value;

producing a word based on the identified sequence of sub-words; and

including the produced word in the combined index.