Understanding Video & App Performance Metrics

Evaluating user experience goes beyond just network speed. Key metrics include PSNR, video freeze duration, and application-level throughput. These metrics together help us understand the Quality of Experience (QoE).

PSNR, Freeze Duration, Throughput Diagram

Figure: Network throughput affects PSNR (video quality) and video freeze duration, both contributing to QoE.

1. Peak Signal-to-Noise Ratio (PSNR)

PSNR measures the quality of video or images after transmission. Higher PSNR means clearer, sharper video; lower PSNR leads to blurry or noisy playback.

2. Video Freeze Duration

Video freeze duration is the total time a video pauses or stalls during playback. Long freezes cause frustration, even if the rest of the video plays smoothly.

3. Application-Level Throughput

This measures the data successfully delivered to the application per unit time. High throughput ensures smooth playback; low throughput may cause buffering and reduced video quality.

Student-Friendly Analogy

  • PSNR: How clear the TV picture is (HD vs blurry).
  • Video Freeze: How often the TV pauses and spins "loading."
  • Throughput: How fast the channel signal reaches the TV.

Together, these metrics define QoE—the real experience of the user.

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