ab-av1

CLI tool for AV1 (and x264/x265) re-encoding using fast VMAF sampling plus automatic CRF binary search to hit a target quality. Wraps ffmpeg/svt-av1/vmaf.

Link

• Visit resource

Related resources

• RefractGuided AVIF/JPEG XL/WebP conversion tool using an iterative quality-search ("optometrist") approach.
• VoltageFFmpeg-based encoding API supporting concurrent instances with a priority/retry job queue and webhook notifications.
• Evaluation of NVENC Split-Frame Encoding (SFE) for UHD Video TranscodingAcademic evaluation of NVENC's split-frame encoding feature for UHD video transcoding throughput and quality.
• Comparing H.265/HEVC and VP9: Impact of High Frame Rates on Perceptual QualityAcademic comparison of HEVC and VP9 codecs under high frame-rate conditions, including ffmpeg/libvpx tuning parameters used.
• Applying Objective Quality Metrics to Video-Codec ComparisonStudy of 789 encoded streams and 320k subjective scores analyzing VMAF correlation per colorspace for codec comparison.
• Differentiable VMAF Re-implementation on PyTorchDifferentiable PyTorch reimplementation of VMAF metric enabling gradient-based codec/RDO optimization, with companion code.
• nano-hevcMinimal educational HEVC encoder written in pure Python, readable-over-fast, for teaching codec internals.
• jxs (JPEG XS reference)Reference software implementation of ISO/IEC 21122-5 (JPEG XS) including jxs_encoder binary, supports PNM/PGX/raw YUV/RGB input.
• Performance Comparison of AV1, JEM, VP9, and HEVC EncodersFraunhofer HHI SPIE 2017 paper comparing codec internals, BD-BR, and complexity across AV1, JEM, VP9, and HEVC.
• Opus (xiph/opus)Reference implementation of the Opus audio codec, recently adding deep-learning-based packet loss concealment.