
Human-machine-interaction is increasingly ubiquitous as technologies leveraging audio and language for artificial intelligence evolve. For many of our interactions with businesses--retailers, banks, even food delivery providers--we can complete our transactions by communicating with some form of AI, such as a chatbot or virtual assistant. Language is the primary component of these conversations and, consequently an essential component to be considered when developing AI.
By combining the processing of language and audio and speech technology businesses can deliver more efficient and personalized customer experiences. This frees humans to spend more time on more strategic, high-level tasks. The potential ROI is enough for many companies to make investments in the technology. As more money is invested, it will lead to more testing, which leads to forward with new developments and best techniques to ensure successful deployments.
Natural Language Processing
Natural Language Processing, or NLP is a subfield of AI which focuses on teaching computers to comprehend and interpret human speech. It's the base of speech annotation tools, text recognition tools, as well as other applications of AI where people converse engage with machine. With NLP employed as an aid in these instances, machines can comprehend human beings and respond effectively, allowing for huge potential across a variety of industries.
Audio and Speech Processing
The field of machine-learning, which includes audio analysis could encompass a range of techniques that include automatic speech recognition, music information retrieval auditory scene analysis for anomaly detection and much more. Models are typically employed to distinguish between sound and speakers by separating audio files in accordance with classes or storing audio files that are based on similar content. It is also possible to take speech and transform it into text easily.
Speech Dataset needs some preprocessing steps, such as digitization and collection before being analysed by an algorithm called ML.
Audio Collection and Digitization
In order to begin the audio processing AI project, you'll require an abundance quality data. If you're in the process of training virtual assistants, voice-activated search features and other transcribing projects, then you'll require specific speech data that can be used to cover the necessary scenarios. If you're not able to locate what you're looking for, then you might have to design your own or partner with a service such as GTS to gather the data. This could include roles-plays, scripted responses, and even spontaneous conversations. For instance, when training a virtual assistant , such as Siri or Alexa you'll require audio of all the commands you might expect your user to provide to their assistant. Other audio projects might require non-speech audio excerpts for example, like cars driving through or children playing according to the purpose.
Audio Annotation
Once you've got enough audio data for the purpose you intend to use it It is necessary to make notes on the data. For the audio process, it generally involves dividing the audio into speakers, layers and timestamps when needed. You'll probably need humans as labelers for this lengthy annotation task. If you're working with data from speech then you'll require annotators that have a good command of the required languages, therefore sourcing them globally could be the best choice.
Audio Analysis
If your data is complete to be analyzed, you'll use one of the many methods to examine it. For illustration, we'll present two sought-after ways to extract information:
Audio Transcription, or Automatic Speech Recognition
Perhaps one of the most commonly used methods of processing audio transcription or Automatic Speech Recognition (ASR) is extensively used in all industries to improve interaction between humans and technology. The aim for ASR is to translate spoken words into text using NLP models to ensure precision. Before ASR existed, computers only record the highs and lows in our speech. Today, algorithms can recognize the patterns of audio recordings, compare them to the sounds of different languages, and figure out the words spoken by each speaker.
An ASR system can include a variety of tools and algorithms to create text output. In general, two kinds of models are used:
1. Acoustic modeling: Turns sound signals into phonetic representations.
2. Model of language:Maps possible phonetic representations to the words and sentence structure which represent the given language.
ASR depends heavily upon NLP to generate precise transcripts. Recently, ASR has leveraged neural networks of deep learning to create output with greater precision and with less supervision needed.
ASR technology can be evaluated on the basis of the accuracy of its technology, as measured in terms of word error rate and speed. The objective to achieve ASR is to reach the same precision that a human listener. However, there are still challenges in navigating the various dialects, accents, and pronunciations, aswell being able to filter out background noises effectively.
Audio Classification
Audio input can be extremely complicated, particularly if many different kinds of sound are included in one. For instance, at the pet park you could hear conversations, birds chirping, dogs barking as well as cars passing through. Audio classification solves the issue by distinguishing audio categories.
The task of determining the audio quality begins with an AI Data Annotation and manual classification. Teams will then find important features from audio signals and then apply a classification system to sort and process them.
Real-Life Applications
Solutions to real-world business issues using speech, audio and processing of language can result in improvements to customer experience as well as reduce costs and time-consuming human labor and help focus attention on higher-level corporate processes. Solutions in this area are prevalent every day. Examples of these solutions are:
1. Chatbots and virtual assistants
2. Search functions that are activated by voice
3. Text-to-speech engines
4. The car's commands
Calls or meetings are transcribable.
5. Improved security through voice recognition
6. Phone directories
7. Translation services
Where did the data come from?
IBM's initial research in the area of voice recognition was component of U.S. government's Defense Advanced Research Projects Agency (DARPA) Effective Affordable Reusable Speech-to Text (EARS) program which resulted in significant technological advancements in speech recognition. The EARS program generated around 140 hours of supervising BN information for training and approximately 9000 hours of light-supervised training data, derived from closed captions in TV shows. In contrast, EARS produced around 2,000 hours of highly supervised human-transcribed training data to train conversations over telephones (CTS).
The business of the day
In the initial group of tests, the team independently tested both the LSTM as well as ResNet models together with the n-gram and FF NNLM before adding scores from both models for comparison to the results of the previous CTS test. In contrast to the results from the initial CTS tests, there was there was no significant decrease in WER (WER) was observed when the scores of both LSTM or ResNet models were merged. The LSTM model that has an n-gram LM is quite effective on its own and its results continue to increase with the addition of the FF-NNLM.
For the second set of experiments, word lattices were generated after decoding with the LSTM+ResNet+n-gram+FF-NNLM model. The team created an n-best list of the lattices, and then rescored them using the LSTM1-LM. The LSTM2-LM could also be used to rescore word-lattices independently. The WER performance was significantly improved following the use of LSTM and LMs. The researchers were able to speculate that the secondary fine-tuning using specific BN data is what enables the LSTM2-LM system to perform better than LSTM1 LM.