The image got heavy selective (=high contrast edge saving) blur to reduce the details. The background was removed in GIMP by manually drawing a clipping path (=actually defined the main outline). Drawing the outlines with the pen tool can sound unpleasant, but if the pen is familiar, drawing can be less work than deleting the unwanted outlines. Remove the fills, give a stroke to the shapesĮdge detecting and tracing easily generate much unwanted outlines, too. The outlines are possible to be made in 3 ways This shows that having only 4 greyshades from black to white, the fake engraving would need outlines and geodetic lines. The same image posterized to 4 greyshades including black and white: The parts are well separated in the posterized version and even the roundness is obvious, so this photo can stay well recognizable when halftoned with hatches that allow 8 greyshades or more evenly distributed from black to white. The left image is an adjusted photo, the right one is the same posterized to 8 levels. One can test, how good his image is for fake engravings by posterizing it to few greyshades.Īn example (done in Photoshop, but is as possible in GIMP): So, we must have an image which is recognizable having only few greyshades. Using plenty of different crosshatches or dashed lines we get more possible greyshades, but we also approach the normal raster halftoning used in printing. If we vary the line width 0.8 pixels, we have more flat distribution of possible greyshades. For example if we have one pixel wide black lines and we vary the space between the lines 0.7 pixels, we have only 8 greyshades + full white - Not very much variation + the step from full black to the next shade 50% grey is quite large. There are only limited amount of different possible line widths or line spacings. This is because the halftoning hatches must be quite dense to appear as halftones. The number of available greyshades is much less than the normal 256. The interesting way: "Adjust your photo and create halftoning with line patterns" Then at first try to trace your photo to BW and if the result is not good enough, get a fake engraving plugin" The easy answer: "Adjust your photo to have a good contrast. How to make fake engravings from photos using only GIMP and Inkscape, no Photoshop nor Illustrator? Making this definitely has been much more work than example 1. Dashed lines are used to give lighter appearance for quite wide lines. Here the line densities vary and several areas also have crosshatches. There are so few greyshades that without geodetic lines the surface forms couldnt be recognized. Obviously drawing plenty of geodetic lines has been a good alternative to having much more simulated greyshades. Here the line usage forms are 1,3, and 4. Geodetic lines (not common engraver's word, used here because there's no better available jus now) which make a greyshade and in addition try to show the curvature of the surface Hatches where the line density is constant, but the varying line widths simulate the greyshades. A variant exists: The line spacing can stay comfortably large, if a part of the lines have different direction (=crosshatching) Hatches where the varying line densities simulates the greyshades. The outlines of the shapes - often drawed, but they can be also left out if the forms are otherwise well recognizable The engravers seem to have four major line usage principles: the greyshades are simulated with line patterns which resemble the engraving patterns.the lines are black on white background.I assume you want to transfer semi-automatically BW photos and other greyscale images to line drawings, where Also I assume that you do not want to trace BW images altough sometimes the result could be good enough. I assume you are not going to engrave onscreen (=draw black lines one by one until the image is ready). Obviously the hat is the interesting part. Your example image has also a grey background pattern, which is not a part of the engraved hat.
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