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Color pictures in black and white pages
It is time for examples of quality photo scans. For that, I took the photo of a page from an Ukrainian album on Kiev (Kyiv). Please note, that this is only to illustrate some procedures and therefore for copyright reasons I spoiled the photo with an overlayed text. The album is larger in size than a home scanner can take, so the photo scanning is the only way to copy the page. The photo scanning setup was not ideal due to a temporary arrangement that I use now. In particular, the lighting was a 50 watt overhead halogen bulb, ceiling lamps switched on, and a lighting diffusor. An ideal setup would require a bright (possibly special photo reprographic) overhead lamp.
In the first attached picture (image processing.jpg) you can see the original photo, the same photo binarized to black and white, and then the same binarized photo with the color picture inserted. To achieve that result you just copy the picture from the color original and paste it into the binarized one. You can do it with the free Irfanview program.
Why should one use color pictures in black and white pages instead of dealing with original color pages? For two reasons. First of all, a book of several hundred pages scanned in color will produce a set of images/pdf file of enormous size. Secondly, the black print in color pages is not quite black and the white background is not quite white. For comparison see the attached pictures (aleksander ocr pdf color.jpg and aleksander ocr pdf bw and color.jpg). The three images of OCRed photos in both pictures are sequentially the following pdf formats: text under picture, text over picture, and text and picture only.
Finally, I attach printscreens (lrf color vs black and white with color picture.jpg) from Sony Reader's Connect software that show lrf pages respectively for color and binarized (with color pictures inserted) pdf pages (text under image) refined with pdflrf program. Although the large size album with small print is not something you would carry with you in the Sony Reader, this example shows vividly the diiference between rendering color and mono pages in the Reader's lrf pages.
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