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PPG 2x-16x Examples

compressionKIT currently ships a set of four reference PPG RVQ operating points that make the compression-versus-fidelity tradeoff easy to evaluate. They share the same overall training flow and differ mainly in how aggressively the signal is compressed.

At A Glance

Variant Archived v1 PRD Retest PRD Archived v1 MSE Retest MSE Best Use
4.76% 4.18% 0.001688 0.001303 Highest reconstruction fidelity
6.18% 5.38% 0.002850 0.002151 Balanced deployment point
8.67% 7.83% 0.005595 0.004556 Strong savings with preserved morphology
16× 11.42% 10.43% 0.009705 0.008099 Maximum reduction for constrained systems

The retest values above were regenerated from the current modular flow and improved on the archived v1 golden baselines across all four operating points.

2× Example

The 2× model is the most conservative option. It is the right starting point when signal fidelity is the first priority and compression is a secondary constraint.

  • Compression ratio: 2×
  • Archived v1 PRD: 4.76%
  • Current retest PRD: 4.18%
  • Archived v1 MSE: 0.001688
  • Current retest MSE: 0.001303

This variant is useful when teams want the reconstructed waveform to remain as close as possible to the source signal while still reducing storage and transfer cost.

4× Example

The 4× model is a strong middle ground and often the best first deployment candidate when the product needs both quality and efficiency.

  • Compression ratio: 4×
  • Archived v1 PRD: 6.18%
  • Current retest PRD: 5.38%
  • Archived v1 MSE: 0.002850
  • Current retest MSE: 0.002151

This is the operating point to evaluate when a program needs visible savings without pushing reconstruction quality to the edge.

8× Example

The 8× model is a more aggressive compression point that still retains the dominant PPG structure well enough for interactive comparison and product evaluation.

  • Compression ratio: 8×
  • Archived v1 PRD: 8.67%
  • Current retest PRD: 7.83%
  • Archived v1 MSE: 0.005595
  • Current retest MSE: 0.004556

For many teams, 8× is where the system-level benefit starts to become immediately tangible without losing the core waveform story.

16× Example

The 16× model is the most aggressive reference point in the documented v1 set. It is aimed at scenarios where bandwidth, storage, or radio energy dominate the design conversation.

  • Compression ratio: 16×
  • Archived v1 PRD: 11.42%
  • Current retest PRD: 10.43%
  • Archived v1 MSE: 0.009705
  • Current retest MSE: 0.008099

This operating point is useful when the question is not whether compression helps, but how far it can be pushed while still preserving the signal information that matters.

Configs Used For The Reference Family

The corresponding golden-style configs live at the repository root:

How To Evaluate Them

The easiest way to explore the family is:

  1. Start at 2× to anchor the quality ceiling.
  2. Move to 4× to establish a balanced operating point.
  3. Jump to 16× to understand the efficiency ceiling.
  4. Use 8× to decide whether the middle-to-aggressive tradeoff fits the target product.

If you want to see these tradeoffs in a more visual and interactive setting, the browser demo is covered in PPG Codec Demo.