US 4,327,375 AGranted

Process and apparatus for providing data indicative of the shape of leaf-like article

AssigneeService d'Exploitation Industrielle des Tabacs et des Allumettes

InventorJean F. Leclerc

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Abstract

Process and apparatus for providing digital data indicative of the contour of a leaf-like article, e.g. a tobacco leaf, and the flaws (holes) that it may comprise, from a video signal composed of image lines. The video signal is coded by comparing same with thresholds so as to detect transitions. The number n of points pertaining to a hole is compared with a threshold n.sub.1, firstly within a line X, then in successive lines X, X+1, and the code is converted to "flaw" when n.gtoreq.n.sub.1. Only when they precede a transition, the coded signals are stored in a memory in the order of appearance of the lines. The stored signals are readout in the opposite order, whereby all the codes pertaining to a given flaw can be rendered uniform and the codes pertaining to unsignificant flaws can be suppressed.

Claims7

Dependent claims

A process for deriving digital information indicative of the outer contour of a leaf-like article and of the holes which it may comprise, said holes having to be taken into consideration for the use of the article when their dimensions exceed a determined threshold, from a sampled analog video signal composed of image lines and representing the image of the article placed on a support, said process comprising the steps of comparing the video signal, for each image dot or sample, with a threshold and coding the dot "1" or "0" according to the result of the comparison;

detecting the transitions in the digital signal thus obtained;
coding this digital signal as a "leaf" signal or word when the signal is in state "0" (or "1") and as a "support" word when the signal is in state "1" (or "0") and when it relates to a hole;
comparing with the above-mentioned threshold, expressed by a number n.sub.1 of image dots, the number n of dots coded "1" (or "0") which follow one another, firstly in a line X (direction Y), then in consecutive lines X, X+1, etc. (direction X);
converting the "support" signals if n.div.n.sub.1, into "flaw" signals and transmitting them unchanged if n<n.sub.1 ;
storing solely the signals preceding a transition, together with corresponding position data Y, by writing them line by line as said lines appear;
reading the stored information in an order opposite the order of writing, whereby line X+1 is read before line X;
transmitting the signals other than the "support" signals unaltered, and processing the "support" signals as follows:
if a "support" signal of a line X is located in the vicinity of a "flaw" signal present in previously read line X+1, it is converted into a "flaw" signal, and if this is not the case, it is not transmitted.

5 more elements

An apparatus for delivering digital information indicative of the outer contour of a leaf-like article and and of holes which it may include, said apparatus comprising:

means for delivering a sampled analog video signal in the form of successive image lines, a comparator for comparing the video signal with a threshold and delivers a digital signal according to said comparison, a coder connected to receive an input signal from the comparator for delivering a pulse when transition occurs in the input signal and for delivering a digital signal or words according to the value of the input signal and the transitions, a processing circuit for receiving the digital signal from the comparator and counting the number of consecutive "1"s (or "0"s) in one line X and in successive lines X, X+1, etc. and delivering "support" or "flaw" words depending on whether said number is lower than or higher than a value n.sub.1, a switching circuit connected to the coder and to the processing circuit for substituting the words from the processing circuit for the corresponding words from the coder, a memory of which the directions of read-in and read-out are opposite and in which the signals from the switching circuit are entered together with their positions Y under the control of the transition pulses from the coder, an output circuit for receiving the stored "support" signals and converting a "support" signal located in line X in the vicinity of at least one "flaw" signal located in the line X+1 into a "flaw" signal and without passing the "flaw" signals from said circuit and the other signals from said memory.

Dependencies are inferred from the claim text.