Developing clip arts using old public domain images
TAt clker.com, we have been adding newer tools that help artists as well as non-artist develop vector illustrations. The most recent tool that we added is a fully automated vectorization tool that vectorizes any high definition photo the user uploads. In our experiments, this automated vectorization tool produced the best results on images of objects with white background, or illustration images with few colors.
We will show a complete example of how to use the output of this tool together with inkscape (from inkscape.org) to produce an illustration image ( clip art ).
 (a) Original |
 (b) Vectorized |
 (c) Clip art |
Figure 1
The original image that was vectorized is an image of a japanese woman sewing. The image was obtained from the library of congress (http://hdl.loc.gov/loc.pnp/jpd.02680). In Figure 1, picture (a) is the original picture. The original picture needs to be at least 0.7 mega pixel and the recommended size is 1 Mega pixel. If the picture resolution is higher than 1 Mega pixel, clker will reduce the size just during vectorization, and that helps with noise reduction.
Picture (b) is the automatically vectorized version. You will notice that when you click the SVG link the picture actually gets rendered in chrome/firefox/opera as SVG.
The third picture, which is the clip art illustration was obtained from (b) using inkscape. The picture was edited and the background was deleted. The Fluorescent color filter was applied to enhance the colors a little bit and the result was uploaded to clker. Producing (c) from (b) is a manual process because a human being is needed, who understands the picture.
 (a) Original |
 (b) Vectorized |
 (c) Clip art, cleaned with inkscape |
Figure (2)
Other examples include the “Lady talking in the phone” in Figure 2. The same exact process was applied. Picture (a) was uploaded with a resolution higher than 1 Mega pixel. After a little bit clker.com vectorized it and (b) was there. The SVG version of (b) was downloaded locally on my computer and edited with inkscape. All the objects around the lady were deleted and left the lady and the phone.
In both those examples the original picture was an illustration and the success rate when dealing with an illustration is higher than photographic images.
An example of a clip art that was generated from photographic image is shown in Figure 3.
(a) Original |
(b) Vectorized |
 (c) Clipart cleaned with inkscape |
The same procedure was applied. However, one has to keep in mind that in photographic images there are lots of gradients, and so the edges of the vectorized version will not be crisp clear and the images might need more work to clean up compared to vectorized illustrations.