Abstract: Three OCR systems are employed for text conversion and the results generated from each of the three are merged using a edit distance algorithm to estimate a correct common text ancestor. To make the process computationally feasible for large strings such as pages of documentation with 3,000 characters, the method is executed in two stages. The first procedure is carried out with each page considered as a string of lines. Where differences exist using the edit distance between the lines on a page to find the optimal alignment of the lines. In the event that choice must be made among three non-null lines, the procedure then is invoked on the three lines , by using the edit distance between the characters on a line to find the optimal alignment. The number of computations required of the procedure is further reduced by comer-cutting that hueristically determines an upper bound on the edit distance and limits calculations to those which do not exceed the upper bound.

Abstract: A process is described for preservation microfilming in which variations in the "fade" or background coloration of materials to be recorded is accommodated for. In particular, the process initially develops a characteristic of the camera based workstation itself which relates an exposure meter output with a select sequence of variations of the light source used with the workstation. A pseudo background target of constant hue such as a beige color is used for this purpose. A sample card also is utilized which carries a sequence of color samples each generally within a pertinent range of the spectra associated with the general coloration of the work to be recorded. Reflectance densitometer readings are taken for each of the samples on this card and the card, itself, is recorded on microfilm. The images of the samples on that test microfilm then are evaluated utilizing a transmittance densitometer.

Abstract: A system and method for treating publisher's textual and graphical data and converting it to device independent digital form for retention in master memory. Once both textual and graphical data have been converted to digital form, the graphical data are inserted in appropriate locations as determined by a formatting routine. Formatted articles then are collected for retention in master memory, and eventual production of local memory. The formatted page files residing in master memory are in a device independent form such that they are outputtable with high quality on a variety of output devices. Additionally, an index is generated for every word retained in master memory enabling the user to peruse as many as 30,000 complex pages for the desired subject matter.

Abstract: A system and apparatus for providing information exchange between a host computer facility and a remotely located user terminal. The host facility includes an audio memory under the control of a host computer which, in response to requests from the user facility is actuated to transmit audio information to the user terminal. During this audio mode of operation, carrier tones are removed and telephone interface components associated with the user terminal and host facility are enabled. The system further includes an interactive audio mode of operation wherein two-way telephonic communication is established between an intermediary or operator associated with the host facility and the user terminal. The related computer programs of the host facility and user terminal are configured such that control over the user facility from the host facility is emphasized.

Abstract: A viewdata system and decoder apparatus for providing interactive communication between a host computer and a consumer which utilizes, without modification, a conventional television receiver. The system utilizes telephonic communication, the handset of a telephone being positioned upon an acoustic coupling arrangement of the housing of the decoder. The decoder automatically carries out logon and logoff procedures through the utilization of memory retained character sequence which are transmitted at predetermined rates. A small, hand-held keypad provides for user interaction with the host computer, such keypad being coupled with the decoder housing through an elongate cable.