A dependency-light Python script that computes MS-SSIM between two image or frame files from first principles. It prints the per-scale contrast x structure (cs) terms across all five scales, the luminance term at the coarsest scale, the calibrated weights, and the final weighted product, alongside the single-scale SSIM for comparison. Includes a --demo mode (fine-grain-noise case), an explicit minimum-size fallback that renormalizes the weights, and the equivalent FFmpeg/libvmaf float_ms_ssim co
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The handbook · 7 volumes
Fora Soft Video Engineering Handbook
This from-scratch MS-SSIM calculator prints the per-scale contrast and structure terms, the luminance term and the weights, so you can see exactly where the final score comes from. Our seven-volume handbook covers the video stack end to end; start with Volume 1 on quality metrics, pixels and color, then Volume 6 on AI models and Volume 3 on QoE monitoring. Written by Nikolay Sapunov, CEO at Fora Soft.
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