A dependency-free (pure standard-library) Python tool that computes BD-rate AND BD-quality from two sets of (bitrate, quality) points, the way the research recommends: SHAPE-PRESERVING monotone PCHIP interpolation (no overshoot), integration in the LOG10-bitrate domain, integration ONLY over the overlapping quality range (IoU reported, thin-overlap warning), and the recommended -10*log10(1-q/qmax) VMAF/SSIM log transform. Point it at your own CSV (bitrate_kbps,quality), or run --dataset on the b
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The handbook · 7 volumes
Fora Soft Video Engineering Handbook
This BD-rate calculator returns BD-rate and BD-quality from two rate-quality curves, integrating only over the overlap and using the log transform for VMAF. Our seven-volume handbook covers the full video stack; start with Volume 1 for rate control and quality metrics, then Volume 3 for ABR ladders and Volume 6. Written by Nikolay Sapunov, CEO at Fora Soft.
Comparing two encoders and need an honest BD-rate number?
Send us your rate-quality points, and we will check the BD-rate math and tell you whether the gain is real. 250+ video products shipped since 2005.
You get a realistic estimate, technical recommendations and next steps. Free, no obligations.
