Image Processing Reference
In-Depth Information
Figure 3.10
Results of crude OCR. A filter implemented in a 5
×
5 window was trained on the
original text image shown in (a). In this case, the “ideal” output was the image shown in (b)
which contained just the letter “e”s. The output from this filter is shown in (c). The result of re-
peating the process for letters “a” and “e” is shown in (d).
knowledge of the alphabet other than the training process and the resulting images
could easily be cleaned up further by post processing, leaving just the characters.
3.2.3 Resolution conversion
An important problem in image processing that is often overlooked is that of reso-
lution conversion. There is little point in having a 600 or 1200 dpi printer if the
