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The Cineon System was a ground breaking computer based digital film system created by Kodak in the early 1990s. It was an integrated suite of components consisting a film scanner, a film recorder and workstation hardware with software (the Cineon Digital Film Workstation) for compositing, effects, image restoration and color management. The system was first released in September 1992 to Cinesite Hollywood. The workstations were initially built on Sun-Transputer based hardware. In July 1993 version 2.1.3 of the software was released for Silicon Graphics Inc (SGI) Onyx hardware. The software was withdrawn from sale by 1997, although a number of customers continued to use it beyond that date. As an end-to-end solution for 4K, 10 bit digital film production, the system was well ahead of its time. The three major components of the system (scanner, workstation software, and recorder) have all received separate AMPAS Scientific and Technical Awards. The project was also responsible for the creation of the Cineon ( .cin) 10 bit log file format designed handle digital film frames. Although the product is no longer for sale, Cineon file format that Kodak defined was for a long time commonly used in the film visual effects world, and formed the basis for the SMPTE-standardised Digital Picture Exchange (DPX) format. ==Cineon file format== The Cineon file format was designed specifically to represent scanned film images, and it has some interesting differences from other formats such as TIFF and JPEG: * The pixel data represents "printing density", the density that is seen by the print film. Thus, Cineon files are assumed to operate as part of a reproduction chain keeping whatever values are originally scanned from a negative or positive film. Any negative can be reproduced on the recorder retaining the original neg's characteristics (such as color component crosstalk and gamma) — and thereby retaining the negative's "look" if it were directly printed. The original Cineon color data metric printing densities were based upon 5244 intermediate film. Conversion of Cineon Printing Density (CPD) to Status-M can be estimated with a 3x3 matrix or by using tables contained in the Kodak "Digital LAD" document. This document shows a specific relation between Cineon Code values and Status-M densities. * The data is stored in log format, directly corresponding to density of the original negative. Since the scanned material is likely a negative, the data can be said to be "gamma with log encoding". * To evaluate original scene luminances from Cineon data, the camera negative characteristics must be known. (Such characterization is known as "unbuilding.") Such characterization is aided by exposing a sensitometric strip so that the actual developing gamma can be determined. The film can be unbuilt by using the unique per-layer contrasts of the color negative. * In a Cineon (.cin) file, each channel (R,G,B) is 10 bits, packed 3 per 32-bit word, with two bits unused. * Conversion to 8-bit integer format for display on computer monitors or transfer to video typically involves the notion of the "black point" and "white point" used for conversion to more limited range video signals. Conventionally, these points are 95 and 685 on the 0-1023 scale (but should be adjusted based upon actual negative content). Pixel values above 685 are "brighter than white", such as the sun, chrome highlights, etc. The concept of a "soft clip" was introduced to make the rolloff of whites appear more natural. Pixel values below 95 represent black values exposed on the negative (the clear base of the film). These values can descend in practice as low as pixel values 20 or 30. Among others FFmpeg and XnView claim to support .cin and .dpx.抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Cineon」の詳細全文を読む スポンサード リンク
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