Audio Search Using Codec Frames for Real-Time Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current audio search systems require significant processing resources for real-time processing and accuracy, with large indexing phases and storage needs, and can produce errors that affect subsequent searches.

Innovation Solution

The system uses frames from an audio signal to look up entries in a lookup table associated with a codec, determining similarities with sound model elements to detect sound bites, words, or phrases, generating events upon detection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If LVCSR is used for indexing phase, then text representation of audio content is achieved, but large processing resources are required and errors limit search accuracy

Engineering Contradiction:
Improvesearch accuracyVSAvoidprocessing resources
Core Design Contradiction:
Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent extracts only the necessary acoustic features from audio frames (codec parameters, energy, zero-crossing rate) rather than performing full LVCSR processing. This extraction approach obtains sufficient information for sound bite detection while avoiding the heavy computational burden of complete speech recognition, thereby reducing processing resources while maintaining detection accuracy

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent segments the audio signal into frames and processes each frame independently using codec-specific lookup tables. This segmentation allows parallel processing of multiple frames with simplified operations, reducing overall processing complexity compared to sequential LVCSR while maintaining comprehensive coverage of the audio content

Inventive Principle:
Principle #1Segmentation

2Adaptability or versatility

If statistical models with multiple states are used, then phoneme detection capability is improved, but processing complexity and storage requirements increase

Engineering Contradiction:
Improvephoneme detection capabilityVSAvoidprocessing complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent changes the parameters used for phoneme detection from complex statistical model states to simplified acoustic features including codec parameters, frame energy, and zero-crossing rate. These parameter changes maintain the ability to distinguish different phonemes while dramatically reducing processing complexity and storage requirements

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent uses lightweight, frame-by-frame acoustic feature analysis instead of heavy statistical models. Each frame is processed independently with simple feature extraction and lookup table comparison, replacing complex long-term statistical modeling with numerous simple, independent analyses that achieve similar detection capability with far less computational overhead

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

3Speed

If index data is stored for later search, then search speed is improved, but disk space requirements increase significantly

Engineering Contradiction:
Improvesearch speedVSAvoiddisk space
Core Design Contradiction:
SpeedVSVolume of stationary object

Solution Approach 1:

The patent stores only the essential acoustic features and codec parameters for each frame in the index, rather than storing complete LVCSR transcripts or complex statistical model data. This partial indexing approach provides sufficient information for rapid sound bite detection while keeping the index size manageable and proportional to the audio duration

Inventive Principle:
Principle #16Partial or excessive action

Solution Approach 2:

Instead of storing processed speech recognition results and searching through text transcripts, the patent inverts the approach by storing raw acoustic features and performing detection directly on these features during search. This inversion eliminates the need for large transcript storage while maintaining fast search capability through efficient feature matching

Inventive Principle:
Principle #13The other way round (Inversion)

Data Source

PatentUS9595264B2Audio search using codec frames
Publication Date: 2017.03.14 ARLINGTON TECHNOLOGIES LLC
  • US9595264B2 patent drawing
  • US9595264B2 patent drawing
  • US9595264B2 patent drawing

AI summary

To detect events in an audio stream, frames of an audio signal (e.g., frames generated by a codec for a voice call or music stream) are received. Based on information in the frames, an index is used to look up an entry in a table associated with the codec. Each entry in the table indicates a likelihood that a frame matches a sound model element. The likelihood is used in the search for a sound bite, word, and/or phrase in the audio signal. The process of dynamic programming is used to find the combined likelihood for a match of the word, phrase, and/or sound bite to a region of the audio stream. Upon detection of the word, phrase, and/or sound bite in the audio stream, an event is generated, such as, notifying a person or logging the event in a database.