Select sources and range
Choose one aligned reference and candidate, then apply one shared inclusive frame range. Source identity, resolution, frame rate, and declared frames establish the expected contract.
Reference comparison
Full-Reference Analysis
Compare an aligned reference and candidate using VMAF, PSNR, and SSIM. Preview, progress, coverage, and scores follow the same selected frame pairs.
Studio workspace
Synchronized evidence, visible while the comparison runs
Reference and candidate previews use equal dimensions. Live values are cumulative and explicitly labeled; pause, resume, and stop operate on the same comparison worker.
Studio screenshot
01
Frame and metric semantics
VMAF, PSNR, and SSIM measure the same selected frame pairs. Inputs must already match in content, dimensions, and frame rate.
Details: Frame and metric semantics
| Measurement | Native scale | Implementation |
|---|---|---|
| VMAF | 0-100 | Every submitted 8-bit I420 decode-index pair is sent directly to libvmaf; the final value is the pooled result for those pairs. |
| PSNR | dB | Direct full-resolution I420 calculation with cumulative Y/U/V values and retained minimum/maximum evidence. |
| SSIM | 0-1 | Non-overlapping 8 x 8 planar SSIM, exported and displayed as (4Y + U + V) / 6. |
| Pair count and coverage | Frames / percent | Studio applies one inclusive frame-index range to both sources. Exports retain selected and compared pairs, both declared frame counts, source coverage, and selected-range coverage. |
Inputs must have matching content, dimensions, and frame rates. CoreVQ does not perform timestamp or offset alignment, dropped-frame compensation, crop, or scale conversion. Missing pairs inside the selected range produce an incomplete comparison; a source-length difference entirely outside a completed selected range does not. The measured domain is 8-bit I420 converted from decoded BGR; it is not HDR-aware and does not evaluate audio.
02
Composite result
The convenience score combines 60% VMAF, 25% normalized SSIM, and 15% normalized PSNR.
Details: Composite result
Full-Reference Score0.60 VMAF + 0.25 SSIM quality + 0.15 PSNR quality
SSIM and PSNR are converted to bounded 0-100 quality components. Available weights are renormalized if a metric is unavailable.
- Measurements
- VMAF, PSNR, SSIM
- Status
- Live / Partial / Final / Incomplete
- Output
- Score, grade, metrics, coverage, components, provenance
03
Execution and export
Select an aligned pair and shared range, then analyze, pause, resume, or stop. Exports retain coverage and partial-result status.
Details: Execution and export
Analyze pairs
A worker decodes the selected same-index pairs, converts them to I420, updates metrics, and emits paired previews and progress within the chosen range.
Control execution
Pause suspends the worker. Resume continues it. Stop preserves completed-pair evidence and labels the result Partial.
Export evidence
CSV and JSON include frame bounds, per-input times, source and selected-range coverage, metrics, composite score, grade, status, warning, and provenance.