Venture Isle is offering for sale or license, US Patent 7,689,404, a method of enabling multilingual speech recognition by reduction to single language recognizer engine components.

The purpose of the invention is to significantly reduce the computational complexity of multilingual or large-vocabulary speech recognition. In addition to the instance where the language of an utterance is not known in advance, applications exist wherein the language may also change during an utterance. Thus business needs increasingly dictate the need for multi-language speech recognition for a wide range of applications.

This patented technology offers a more efficient means of enabling existing single language recognizers to support multiple languages simultaneously. This technology overcomes traditional challenges and complexities of multilingual speech recognition. Traditional or prior art solutions include:

1. The requirement to pre-specify the language before recognition can occur or,

1. Determining the language based on a small vocabulary of wake-up or activation phrases or commands or

1. The need to run multiple single language recognizers in parallel or

1. Creating hugely complex monolithic multilingual recognizers that support all languages

In contrast, the method described in the patent utilizes existing components of single-language speech recognizer engines by combining and controlling them in a way that enables automatic multilingual speech recognition across a range of supported languages and dialects.

A new component, the ‘Multilingual Dispatcher’ (MLD) envelops language independent components and invokes language-specific components to perform language-dependent processing.

The MLD dispatches certain requests to individual recognizers, aggregates their responses and keeps track of the recognized sequence. The dispatcher is agnostic to how the single-language recognizers work internally. Thus, the hypotheses space is decomposed into sub-spaces visible to individual recognizers, which reduces the complexity. Moreover, language-specific components themselves are not affected when a language is added or removed from the application.

A ‘language’ is applicable for anything for which a recognizer exists, so the invention applies to both different spoken languages and different recognizer models or engines for different subsets of the same spoken language.

Key elements of the invention include a heuristic way to make numeric scores of hypotheses (such as Viterbi scores) comparable even if produced by different language-specific recognizers and a heuristic way of propagation of (seeding) a hypothesis from a hypothesis in a different language. Specific language support works like a replaceable plug-in thus creating a structure that enables scalable deployment of any subset of supported languages in short order.  

Benefits of the MLD technology include:

• Increased modularity and flexibility- additional languages can be added or removed without requiring major reconfiguration

• Less complex multilingual implementation – faster time to market

• Enable multi-language speech recognition with a smaller memory requirement – less cost and smaller footprint

• Quicker execution times than alternative technologies – better user experience

• Lower overall system costs

• Lower on-going support costs

The technical description in the patent is concerned with a single pass of recognition. In addition there are multiple-pass recognizers and the invention of combining single-language recognizers into a multilingual recognizer applies to any or all passes of multiple-pass engines.

FOR MORE INFORMATION