This invention relates to the simulation of video images originated on motion picture film stocks, from high definition video originated material stored on tape.
Film has been the preferred recording medium on which to originate many productions broadcast on television for years because of the sophisticated visual impression provided by the character of film stocks' color response and the general audience familiarity with the appearance resulting from filmed material presented on television; the resulting "look", a product of the photo-chemical process preceding the production of television signals representative of the image stored in the photo-chemical process, differs in several ways from video originated material of an identical photographic subject. Two key ways in which they differ are the focus of this invention: The color and grey scale component value response in each pixel of the resulting image on a television monitor; and the subtle visual impression made by the textured appearance of film grain, which is inherent to images stored within motion picture film emulsion.
Though color negative film has the ability to reproduce abundantly more color and grey scale gradients than video originated images, when video images are created from filmed images by means of a standard telecine "flying spot scanner" transfer, an illusion of the entire range of film's color response is maintained. This phenomenon, occurring within the scope of the video medium, provides that constants exist that can define the variation in pixel response between film and video originated images shot under identical lighting conditions, when viewed on video monitors: It is the combination of filmed information as it can be reproduced on a monitor that provides the overall maintenance of the "film look", and each separate color component combination of each pixel of film originated image is in fact available and employed by video originated images, though in response to a different photographic stimulus in almost every case.
The video data resulting from a telecine transfer defines filmed images in video terms, so the medium in question is in fact video, and the parameters and actual subtleness of projected filmed images are not the issue. Rather, the video data assigned to a resulting pixel representing a zone of film emulsion is an averaging process provided by video standards and color and grey scale gradients recognized as those registered and visible on standard television receivers.
Digital video technology has provided that digital data defines video images and encodes the color and grey component values for each pixel in addressable sequences, able to be "read" and "rewritten" into a store. Therefore, given uniform and predominantly shadow-free lighting and even color temperature during original videotaping, and careful slating of this data for each shot in foot candles and degrees kelvin respectively, digital data logged from pixel response of color data originally stored in film stock emulsion, under the same light intensity and color temperature conditions, can be referenced according to principal videographic variables and inserted in place of the original video color data. This would create an aesthetic comprise that permits approximation of potentially any film stock's anticipated response to the same stimulus represented in video form.
Existing technology for the printing industry and digital video provide for scan-sequential and specifically addressed pixel component modifications according to look-up-table data, as the system of the present invention employs, (i.e. U.S. Pat. Nos. 4,727,425; 4,710,806.)
New high definition television systems and video projection systems capable of manifesting a high definition compatible number of scanning lines provide the means for executing a process whereby actual film grain within celluloid emulsion can be married with a projected image, and videographed with a loss in image clarity low enough to produce a final result which provides a film "look" to images at an aesthetically acceptable sacrifice to the original high definition integrity of the video images. Present systems strive to simulate film grain appearances digitally, with a result that is visibly different from actual film grain appearances on monitors, following a telecine "transfer." By incorporating the general videography-of-film operating basis of telecine devices, high definition projection and camera units mounted on tracks, with macro lensing, "gen-lock" synched together, matching scan lines to the highest degree possible can capture a complete video frame as it is projected on a grey emulsion surface of optional size. This recreation of a video signal of a high number of scanning lines from a high definition projection would have a resulting actual clarity substantially less than that of the original video material, but with the aesthetic look of film originated images. Present systems for providing an NTSC signal from a high definition signal may be employed at this stage, or the signal may be maintained as as higher definition signal for recording, monitoring or broadcasting.
So, for many television applications where film is shot for telecine transfer to video, there are benefits to be gained by employing the system of the present invention. At the production level: a television camera is employed instead of a film camera providing silence; immediate screening of the actual material shot; immediate sound synching; lesser risk of reshoots from screening original material for problems immediately; and no expense of negative film. In post production: processing of film, transfer to video and sound synching are not needed; having shot video, dailies need not be awaited; all shot selections destined for final modification by the "FILMITATOR" system are made in preliminary "off-line" edit sessions, minimizing the actual amount of material submitted for modification and thus time charges as opposed to a film shoot where typically all material must be transferred to tape, at substantial expense, for initial screening; and during modification by this system, a variety of film stock component response and film grain options may be previewed and imparted to the original video material, providing a unique range of new post-production aesthetic effects to video originated material.