| 摘要 |
Apparatus, and accompanying methods, for determining appropriate sampling points located throughout a scanned microfilmed bit-mapped "data strip" in order to properly extract the values of stored data bits therefrom. Each data bit is formed of a contiguous group of one or more pixels in the data strip. Specifically, my technique involves parsing the data strip into successive vertical strips that each has successive rows of pixels, determining inter-row and inter-pixel differential intensity values for each vertical strip, and defining vertical line addresses and horizontal pixel addresses in each of the strips as a function of the pixel positions of the inter-row and inter-pixel differential intensity values associated therewith. The individual pixels in each vertical strip, which are situated at the horizontal pixel addresses and which lie on those rows in that vertical strip specified by the vertical line addresses, are sampled in order to yield sampled pixel data. All the sampled pixel data collectively represents the values of the data bits stored in the data strip. Advantageously, the line and pixel addresses will appropriately change in response to skew that occurs between the data strip and a microfilm line scanner as the data strip is being scanned and/or to changes in data bit size that occurs from one data strip to the next.
|
