Abstract: A linear light source for a film scanner is disclosed which includes an elongated light integrating cavity having diffusely reflective walls. Light is introduced into the cavity through an input port, and an output beam of diffuse illumination is produced through a slot which is generally parallel to the longitudinal axis of the integrating cavity. In order to provide a light source which can produce a beam of a desired angular distribution, plates are positioned adjacent the exit slot of the cavity to form channels through which the light exits.

Abstract: The present invention efficiently and quickly computes the fit parameters for a noise reduction method wherein a digital image is first decomposed into two types of regions; smooth regions and edge regions. Within the digitized image a plane fit parameter is computed at every point. The computation of the fit parameters incorporates convolutions carried out in an efficient manner by the use of a slide sum technique.

Abstract: An interactive dynamic range adjustment method for printing digital images, and an implementation system, are disclosed. The method is based on experimental findings about visual photoreceptor adaption and human visual contrast sensitivity. The system adjusts the contrast of the low-frequency component only of the image, preserving (or if one wishes, enhancing) the high-frequency image component in its contrast. The adjustment is controlled by a mapping curve which the user manipulates interactively. The simulated optical print image and the dynamic range adjusted image are displayed side by side on a monitor screen so that the user can make proper selection of parameters to achieve the desired effect. For many images, the system automatically computes good parameters and no further adjustment is needed.

Abstract: At least one frame of a strip of photographic film is exposed to an image, and, prior to being developed, six (or so) calibration strips in a specially reserved frame on the same film are individually exposed to six predetermined calibration light sources producing six progressively increasing exposure levels spanning the exposure latitude of the film. A film layer develops a positive image in one color and a negative image in another color using positive and negative dyes, respectively. The film is scanned to determine the positive and negative dye amounts, D.sub.p and D.sub.n at each scanner pixel. The likeliest exposure value E as a function of D.sub.n and D.sub.p is determined probabilistically from six histograms obtained by scanning the six calibration patches on the film, all of the E's thus obtained being stored in a look-up table addressed by the corresponding values of D.sub.p and D.sub.n. The images recorded on the film are then scanned pixel-by-pixel, the D.sub.p and D.sub.