Marked card reader

A data encoding system, comprising:

• a supply of sheets having predetermined areas for receiving handwritten marks, the sheets bearing distinctive identification marks at spaced locations, the identification marks being positioned in predetermined relation to the areas for receiving handwritten marks;
• illumination means for the sheets and an image recorder operative to record in an image buffer a matrix of data points representing frozen-frame grey levels of pixels within a length and width on the sheets, the length and width including the identification marks;
• a data processor operative with the image buffer to define potential mark areas on the sheets relative to the identification marks;
• a discriminator having weighting and arithmetic elements operative to discern marks in the potential mark areas by weighting grey levels at a part of the potential mark areas and subtracting from the weighted grey level values of areas nearby said central part, the result indicating a mark present.

A mark sensing card reader for discerning presence of handwritten marks on potential mark fields on a plurality of cards, the cards having indicia at spaced locations, the indicia being distinctive of a certain product, the reader comprising:

• a planar image sensing device with drive and amplification means operative to capture analog data representing an image signal across an entire length and width of a field on successive ones of the cards fed into the reader;
• an analog to digital converter operative to digitize the analog signal into a matrix of pixel data points having variable grey levels;
• an image memory for storing said data points;
• means operable to detect the presence of said indicia distinctive of the certain product and to determine a position thereof in the image memory;
• a data processor operable to address data in the image memory to map said pixel data points relative to the indicia distinctive of the certain product and to define potential mark addresses within the matrix of pixel data points;
• and
• a contrast discriminator comparing the grey levels at pixels at said potential mark addresses with grey levels nearby said potential mark addresses, for discerning presence of said marks.

A method for reading a lottery game card having handwritten marks positioned thereon to indicate data, the method comprising the steps of:

• recording an instantaneous image of the card, the card having at least two spaced identification marks printed thereon;
• defining a plurality of potential mark areas with respect to the identification marks;
• comparing contrast between a central part of the potential mark areas and parts adjacent to the central part, thereby discriminating presence and absence of marks;
• and,
• storing the data.