Root Delta Image (RDI): A Low-Complexity Lossy Still-Image Format with Scanline Root-Delta Prediction

Root Delta Image (RDI): A Low-Complexity Lossy Still-Image Format with Scanline Root-Delta Prediction | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Root Delta Image (RDI): A Low-Complexity Lossy Still-Image Format with Scanline Root-Delta Prediction Anar Bastanov, Vecdi Emre Levent This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8705345/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Modern image codecs achieve impressive compression ratios, but their bitstreams and decoding pipelines have grown complex enough that implementing and hardening a decoder is often more challenging than the image-processing task that motivated the decoder in the first place.This work presents Root Delta Image (RDI) , a compact, intentionally low-complexity lossy raster format designed around (i) a reversible integer color decorrelation transform (YCoCg), (ii) per-scanline prediction with a constrained 4-bit root-delta quantizer, (iii) optional 2 \((\times)\) 2 chroma subsampling, and (iv) a file layout consisting of a fixed-size header plus exactly one \texttt{zlib}/DEFLATE-compressed payload.RDI trades compression efficiency for analyzability: the format has explicit size bounds and deterministic decode procedures that are expressible with bounded loops, integer arithmetic, and a single call to a commodity DEFLATE implementation.We summarize the format specification, describe a reference implementation, and evaluate two practical nibble-packed modes on natural images.Across the Kodak image suite and two TestImages.org subsets, RDI achieves perceptual similarity comparable to baseline JPEG at common quality settings while typically requiring higher bitrates; at the same time, it yields substantial size reductions compared to lossless PNG.We position RDI among predictive and transform-based codecs and highlight properties that are particularly relevant to embedded and security-sensitive deployments: compact decoding logic, predictable memory use, and a validation-first bitstream structure. Image compression low-complexity codec predictive coding delta coding YCoCg DEFLATE secure parsing embedded systems Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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