The Data Challenge in Accented English Speech Recognition

Accented English represents a fascinating and diverse linguistic tapestry, reflecting the global reach of the English language. However, when it comes to automatic speech recognition (ASR) systems, the rich array of accents can present a substantial challenge. This article explores the complexities of recognizing accented English in the context of speech recognition and the ongoing efforts to address this challenge.

 

The Diversity of Accented English

 

Accented English encompasses a wide range of pronunciation, intonation, and rhythm variations. It includes accents from various regions, such as British English, American English, Australian English, Indian English, and many more. These accents exhibit distinct phonological features, often differing significantly from one another and from standard English. Recognizing and understanding this diversity is essential for effective communication and speech technology.

 

The Accented English ASR Challenge

 

ASR technology aims to convert spoken language into written text, making it a valuable tool in a variety of applications, from transcription services to voice assistants. However, recognizing accented English poses unique difficulties:

 

Accent Variability: Accents can exhibit significant variability even within their categories. For example, the British English accent varies considerably across regions like London, Birmingham, and Glasgow. ASR systems need to account for these nuances.

 

Data Scarcity: Building robust ASR models requires large and diverse datasets for training. However, there is often a shortage of high-quality accented English speech data, especially for less common accents. This data scarcity can hinder the development of accurate models.

 

Out-of-Vocabulary Words: Accented English may introduce variations in pronunciation and vocabulary that are not present in standard English. ASR systems must adapt to these variations and be able to handle out-of-vocabulary words.

 

Speaker Independence: ASR models should ideally be speaker-independent, meaning they can recognize any speaker's accent. Achieving this level of generalization is challenging, as accents introduce variations that can be specific to individuals.

 

Nexdata Accented English Training Datasets

 

117 Hours - Latin American Speaking English Speech Data by Mobile Phone 

281 Latinos recorded in a relatively quiet environment in authentic English. The recorded script is designed by linguists and covers a wide range of topics including generic, interactive, on-board and home. The text is manually proofread with high accuracy. It matches with mainstream Android and Apple system phones.

 

18 Hours - Brazilian English Speech Data by Mobile Phone 

18 native Brazilian speakers were involved, balanced for gender. The recording corpus is rich in content, and it covers a wide domain such as generic command and control category, human-machine interaction category; smart home category; in-car category. The transcription corpus has been manually proofread to ensure high accuracy.

 

207 Hours – Canadian Speaking English Speech Data by Mobile Phone 

466 native Canadian speakers involved, balanced for gender. The recording corpus is rich in content, and it covers a wide domain such as generic command and control category, human-machine interaction category; smart home category; in-car category. The transcription corpus has been manually proofread to ensure high accuracy.

 

1,012 Hours - Indian English Speech Recognition Data by Mobile Phone

Indian English audio data captured by mobile phones, 1,012 hours in total, recorded by 2,100 Indian native speakers. The recorded text is designed by linguistic experts, covering generic, interactive, on-board, home and other categories. The text has been proofread manually with high accuracy; this data set can be used for automatic speech recognition, machine translation, and voiceprint recognition.

 

535 Hours - German Speaking English Speech Recognition Data by Mobile Phone 

1162 native German speakers recorded with authentic accent. The recorded script is designed by linguists and covers a wide domain of topics including generic command and control category; human-machine interaction category; smart home command and control category; in-car command and control category. The text is manually proofread to ensure high accuracy. It matches with main Android system phones and iPhone. The data set can be applied for automatic speech recognition, voiceprint recognition model training, construction of corpus for machine translation and algorithm research.