Subjective speech quality measurement with and without parallel task: Laboratory test results comparison

Area of Science:

• Speech processing
• Acoustics
• Human-computer interaction

Background:

• Subjective speech quality assessment is crucial for telecommunications.
• Existing methodologies may be influenced by testing conditions.
• The ITU-T P.835 standard provides a framework for speech quality evaluation.

Purpose of the Study:

• To introduce and validate a novel methodology for subjective speech quality measurement.
• To assess the repeatability of speech quality measurements across laboratory and simulated environmental conditions.
• To investigate the impact of a parallel task on speech quality test outcomes.

Main Methods:

• Speech samples were degraded using background noise and low bit-rate coding.
• Subjective speech quality tests were conducted with and without a parallel task.
• The ITU-T P.835 methodology was employed.
• Statistical analyses included Pearson correlation, confidence intervals (CI95), and opposite pair comparisons.

Main Results:

• The novel methodology demonstrated repeatability between different testing environments.
• The inclusion of a parallel task led to observable differences in the measured speech quality.
• Statistical comparisons revealed significant variations when a parallel task was present.

Conclusions:

• The proposed subjective speech quality measurement methodology is robust across varied conditions.
• The presence of a parallel task significantly influences subjective speech quality perception.
• Further research should consider the role of parallel tasks in speech quality assessment.