Voice Technologies

  1. Automatic Speech Recognition
    1. ASR System Architecture
      1. Pipeline Overview
        1. Signal Processing Frontend
          1. Feature Extraction Stage
            1. Acoustic Modeling
              1. Language Modeling
                1. Decoding Process
                2. System Integration
                  1. Component Interfaces
                    1. Data Flow Management
                      1. Error Handling
                        1. Performance Optimization
                      2. Acoustic Modeling
                        1. Traditional Approaches
                          1. Hidden Markov Models
                            1. State Structure
                              1. Transition Probabilities
                                1. Emission Probabilities
                                  1. Training Algorithms
                                  2. Gaussian Mixture Models
                                    1. Component Estimation
                                      1. EM Algorithm
                                        1. Model Selection
                                          1. Adaptation Techniques
                                        2. Neural Network Approaches
                                          1. Deep Neural Networks
                                            1. Architecture Design
                                              1. Activation Functions
                                                1. Training Procedures
                                                  1. Regularization Methods
                                                  2. Recurrent Neural Networks
                                                    1. Vanilla RNNs
                                                      1. Long Short-Term Memory
                                                        1. Gated Recurrent Units
                                                          1. Bidirectional Processing
                                                          2. Convolutional Neural Networks
                                                            1. 1D and 2D Convolutions
                                                              1. Pooling Strategies
                                                                1. Feature Map Interpretation
                                                              2. Advanced Architectures
                                                                1. Connectionist Temporal Classification
                                                                  1. Alignment-Free Training
                                                                    1. CTC Loss Function
                                                                      1. Decoding Algorithms
                                                                      2. Attention Mechanisms
                                                                        1. Attention Types
                                                                          1. Alignment Learning
                                                                            1. Context Vector Computation
                                                                        2. Language Modeling
                                                                          1. Statistical Language Models
                                                                            1. N-gram Models
                                                                              1. Unigram through N-gram
                                                                                1. Smoothing Techniques
                                                                                  1. Back-off Strategies
                                                                                    1. Interpolation Methods
                                                                                    2. Model Evaluation
                                                                                      1. Perplexity Calculation
                                                                                        1. Cross-Entropy
                                                                                          1. Out-of-Vocabulary Handling
                                                                                        2. Neural Language Models
                                                                                          1. Feedforward Networks
                                                                                            1. Recurrent Language Models
                                                                                              1. Transformer Architecture
                                                                                                1. Self-Attention Mechanism
                                                                                                  1. Positional Encoding
                                                                                                    1. Multi-Head Attention
                                                                                                    2. Pre-trained Models
                                                                                                      1. BERT and Variants
                                                                                                        1. GPT Family
                                                                                                          1. Fine-tuning Strategies
                                                                                                      2. Decoding and Search
                                                                                                        1. Search Algorithms
                                                                                                          1. Viterbi Algorithm
                                                                                                            1. Dynamic Programming
                                                                                                              1. Trellis Structure
                                                                                                                1. Backtracking
                                                                                                                2. Beam Search
                                                                                                                  1. Pruning Strategies
                                                                                                                    1. Beam Width Selection
                                                                                                                      1. Length Normalization
                                                                                                                    2. Advanced Decoding
                                                                                                                      1. Weighted Finite State Transducers
                                                                                                                        1. Lattice Generation
                                                                                                                          1. N-best List Generation
                                                                                                                        2. Modern ASR Architectures
                                                                                                                          1. End-to-End Models
                                                                                                                            1. Listen Attend and Spell
                                                                                                                              1. Encoder-Decoder Framework
                                                                                                                                1. Attention Mechanisms
                                                                                                                                  1. Teacher Forcing
                                                                                                                                  2. RNN Transducer
                                                                                                                                    1. Streaming Capability
                                                                                                                                      1. Alignment Learning
                                                                                                                                        1. Prediction Network
                                                                                                                                        2. Transformer-Based ASR
                                                                                                                                          1. Conformer Architecture
                                                                                                                                            1. Self-Attention in ASR
                                                                                                                                              1. Positional Encoding
                                                                                                                                            2. Hybrid Systems
                                                                                                                                              1. HMM-DNN Integration
                                                                                                                                                1. Tandem Systems
                                                                                                                                                  1. Bottleneck Features
                                                                                                                                                2. ASR Evaluation
                                                                                                                                                  1. Error Metrics
                                                                                                                                                    1. Word Error Rate
                                                                                                                                                      1. Calculation Methods
                                                                                                                                                        1. Statistical Significance
                                                                                                                                                        2. Character Error Rate
                                                                                                                                                          1. Phoneme Error Rate
                                                                                                                                                          2. Error Analysis
                                                                                                                                                            1. Substitution Errors
                                                                                                                                                              1. Insertion Errors
                                                                                                                                                                1. Deletion Errors
                                                                                                                                                                  1. Error Pattern Analysis
                                                                                                                                                                  2. Robustness Testing
                                                                                                                                                                    1. Noise Conditions
                                                                                                                                                                      1. Speaker Variability
                                                                                                                                                                        1. Domain Adaptation
                                                                                                                                                                          1. Cross-Lingual Evaluation