1,721,000 research outputs found
Motion Picture Colour Science and film ‘Look’: the maths behind ACES 1.0 and colour grading
No full textOne of the biggest colour-related problems for the film production and post-production industry is two-fold: to ensure that the creative“look” of video content, as envisioned by the cinematographer, is preserved throughout ([1]– [2]), and to be able to consistently reproduce this ([1], [3]). That also has to be independent both on digital cameras or computers generating and animating it (as input), and on finished asset specifications for the end-users to watch and enjoy it (as output) — be it either in a dark digital cinema theatre, at a home TV setting, or using a Video-on-Demand (VoD) or Internet- streaming application, in a day-lit room or even open sunlight. In recent years many proprietary/commercial tools and workflows emerged, each driven by specific, not always cross-compatible needs (e.g. on-set grading, Digital Cinema mastering, VoD, etc.). This results in proliferation of a plethora of different formats vs. the scarce number of really interoperable standards.
After a minimal introduction to colour-mathematical terminology ([4]–[6]) and ColorLUTs, two brand new colour-management techniques from high-profile moving-picture digital imaging (CDLs and ACES) will be described, as they aim at colour interoperability for the analysis and synthesis of digital ‘looks’, both on-set (production) and along the Digital Intermediate (DI) phase.
ACES in particular, which the author has been active contributor to since 2012, is an Academy-originated initiative for facilitating colour interoperability across the Media & Entertainment industry
Colour correction calculus (CCC): engineering the maths behind colour grading
No full textTo date, the digital world of still and moving pictures for video is almost essentially based on the 3-channel additive colour model, i.e. a plethora of RGB colour spaces. When it comes to creative or technical colour manipulations done digitally (be it either as part of on-location workflows, or during a post-production pipeline in a colour-correction theatre) controls available to artists and engineers range from very intuitive up to extremely new and nonlinear tools. By employing a unified yet simple and novel vector-based formalism typical of mathematical and physical field theories, [1], the author starts from classic Colour Science equations ([2]–[5]) and shows how this formalism may help to “part-and-divide” typical problems in in motion picture colour management, with the aim of simplifying and more consciously apply specific colour-related operations to footage.
Video and film colour correction, particularly the one that is accomplished in the Digital Intermediate (DI) workflow inside a properly colour-calibrated DI theatre, is traditionally divided into various ‘canonical’ phases; the first affecting the picture as a whole (i.e. the same colour mappings are applied the same to every pixel in the frame) and called primary colour correction (CC); then comes the phase where only selected regions of the image (either static or moving) are colour-processed, and called secondary CC; then other oadditional phases may jump in. Secondary CC is the most important one from the creative point of view, where mathematical tools are essential to deliver, effectively, precisely and as quickly as possible, the Author of Photography’s creative intent
The Academy Color Enconding System (ACES) in a video production and post-production colour pipeline
No full textColour management for video-based projects involves transferring large quantities of data —currently 1–3 TB (terabytes) per shooting day, or 1–6 TB per finished full-feature Digital Cinema Master— around different locations and facilities, during a timespan of several months, and having them processed by highly heterogeneous IT infrastructures, each with its peculiar viewing environment at the end (displays, TVs, monitors, projectors). Add to this the different imaging characteristics of camera sensors and purely artificial imagery / computer graphics (CG).
To cope with such a diverse ecosystem, the Academy of Motion Picture Arts and Sciences (AMPAS), as it did many times in the past (from the silent-film era up to current immersive-sound, HFR and HDR breakthroughs), gathered an international group of scientists, cinematographers, developers, colourists and engineers —which the author is among— to came up with a framework called the Academy Color Encoding System (ACES, [1]) encompassing colorimetry, advanced mathematics ([2]), metadata and computer-science security to streamline an easier, more interoperable and durable process which is colour-accurate for every creative, technical and archival needs of visual contents. After a general understanding of ACES as a whole, the author will focus on his own contributions to the project: some of the ACES colour-mathematics internals, and aspects of colour representation and transmission as metadata, [3]–[6]
Topological Calculus: between Algebraic Topology and Electromagnetic fields
No full textThe Topological Calculus, based on Algebraic Topology, is introduced as a discrete Field Theory. Diagonalization of simplicial complex adjacency matrices allows to extract information about domain topology and Helmholtz equation eigenfunctions. Electromagnetic analysis of IFS fractals for Sierpinski gasket/carpet is then carried out: self-similar topology deeply influences the type of e.m. fields, as well as its finite TEM modes (as many as the domain's Euler characteristic; represented by harmonic fields) and self-similar distribution of resonating frequencies. This proves that even in such discrete model many features of guided waves depend on the topology rather than metrics
Fractal Riemann Surfaces: Chaotic Scenarios and Applications
No full textFractal Riemann surfaces are generated as iterators of branched covers (complex multi-valued functions). They feature self-similar geometries, an interesting iterated monodromy group (IMG) driving their topologies, and an easy way to get their symbolic dynamics browsed. On the contrary, convergence issues, numerical accuracy and the onset of chaotic dynamics are present in the direct, homotopy problem of computing paths on them. Theoretical results of analysis and synthesis will be given, with a final look to possible applications in Computer Science (signing and private-key cryptography) and Physics (scattering in fractal resonators)
Kernel- and CPU-level architectures for computing and A\V post-production environments
No full textHigh-Performance Computing has been improving for the last decades through more parallelism and high-level machine instructions. Multimedia applications for Audio\Video post-production also rely on fast algebraic data manipulation, which is though not fully supported at CPU and OS kernel levels yet. After a brief review on current hardware and software implementations, several steering proposals towards future architectures for both HPC and A\V post-production environments, as well as OS human interfaces is sketched here
Method and apparatus for delocalized management of video data
No full textA method for managing video data in a storage system, the video data comprising frames, and a storage system (10) configured to perform the method are described. The storage system (10) comprises a first input (11) configured to receive (1) one or more frames for storage. A storage more frames unit (12) stores (2) the one or more frames, whereas a unique identifier generator (13) associates (3) a unique identifier to each of the one or more frames. The storage system (10) further comprises a processor (14) configured to generate (4) a modified frame by processing one or more frames or to receive a modified frame generated externally. The unique identifier generator (13) associates (5) a derived unique identifier to such a modified frame, which comprises refer ences to the unique identifiers of the one or more processed frames
Linee guida Attribute Authority: allegato tecnico SAML —‒ Sistema di Gestione delle Deleghe Digitali (SGD)
No full textIl presente Allegato Tecnico alle Linee Guida sulle Attribute Authority, pubblicate dall’Agenzia per l’Italia Digitale (AgID), descrive l’implementazione mediante protocollo SAML adottato inizialmente per un particolare gestore di attributi qualificati: il sistema di gestione delle deleghe digitali (SGD).
Il documento è stato sottposto a consultazione pubblica nel mese di giugno 2021 sulla piattaforma docs.italia.i
Method and apparatus for preparing video assets for processing
No full textA method and an apparatus for preparing video assets for processing are described. Via an input (21) a list of video assets required for processing is retrieved (10). A source locator (23) determines (11) source locations of the required video assets. A data handling unit (26) then makes (12) the required video assets available at a target location
Method and apparatus for handling data in a storage system
No full textA method for handling data in a storage system (25) and an apparatus (20) configured to perform the method are described. In particular, in order to store data in the storage system (25), the data being provided as a set of files, a file distributor (22) distributes (11) the files over two or more file systems. Each file system has a data path. A file system generator (23) generates (12) a virtual file system comprising pointers to the distributed files within the two or more file systems. For reading data from the storage system (25), a file system retrieving unit (26) retrieves (13) the virtual file system. A data interface (24) then reads (14) a set of files from the two or more file systems based on the virtual file system using two or more I/O threads
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