Editing Capturing Handwriting

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==== Bitmap Tracing ====
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==== Tracing bitmaps ====
  
 
When you scan or take a picture of vector artwork, or convert vector artwork into a bitmap format (for example by saving as a JPG file), you are ''removing the directional information from the artwork''. You are removing the data that says where each stroke starts and stops, and replacing it with a grid of color values.  
 
When you scan or take a picture of vector artwork, or convert vector artwork into a bitmap format (for example by saving as a JPG file), you are ''removing the directional information from the artwork''. You are removing the data that says where each stroke starts and stops, and replacing it with a grid of color values.  
  
To convert back from that grid of colored pixels into a list of strokes and directions is a complex problem that does not always have a clear solution. A simplistic approach is to draw vector contours around brightness levels -- this the type of automatic "outline tracing" that Inkscape's Trace Bitmap tool uses. You can find this tool in the menu as Path > Trace Bitmap.  This type of tracing tool is well suited to simple outline shapes that do not have complex internal structure.  
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To convert back from that grid of colored pixels into a list of strokes and directions is a complex problem that does not always have a clear solution. A simplistic approach is to draw vector contours around brightness levels -- this the type of "outline tracing" that Inkscape's Trace Bitmap tool uses. You can find this tool in the menu as Path > Trace Bitmap.  This type of tracing tool is well suited to simple outline shapes that do not have complex internal structure.  
  
 
This type of tracing usually results in plotting "double" lines around each stroke, since it is showing the outlines, and that can result in plotted letters that look hollow. In some cases a broad-nibbed fountain pen (or Sharpie) has a width that is sufficient to hide the fact. You can help a little bit by using an inset operation (In Illustrator, Effect > Path > Offset path), to make the width smaller. You might also consider using a smaller nibbed pen, but filling the text in the usual way so that it is not hollow.
 
This type of tracing usually results in plotting "double" lines around each stroke, since it is showing the outlines, and that can result in plotted letters that look hollow. In some cases a broad-nibbed fountain pen (or Sharpie) has a width that is sufficient to hide the fact. You can help a little bit by using an inset operation (In Illustrator, Effect > Path > Offset path), to make the width smaller. You might also consider using a smaller nibbed pen, but filling the text in the usual way so that it is not hollow.
  
  
==== Centerline Tracing ====
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==== Center tracing ====
  
A slightly more advanced type of bitmap tracing tries to draw centerlines through these contours, in order to estimate where the initial lines were located. This is called "center" or "centerline" tracing. And, while it sounds like a good idea in practice, the results of automated centerline tracing software are rarely good enough to pass for human handwriting, since the tracing tool has no intuition about how the lines should connect together, or appear when they overlap.
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A slightly more advanced type of bitmap tracing tries to draw centerlines through these contours, in order to estimate where the initial lines were located. This is called "center" or "centerline" tracing. And, while it sounds like a good idea in practice, the results are rarely good enough to pass for human handwriting, since the tracing tool has no intuition about how the lines should connect together, or appear when they overlap.
  
 
Here is an online program that can take your scanned text and convert it by center tracing to an SVG file that can opened in Inkscape: http://online.rapidresizer.com/tracer.php   
 
Here is an online program that can take your scanned text and convert it by center tracing to an SVG file that can opened in Inkscape: http://online.rapidresizer.com/tracer.php   
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''Aside:'' Going several steps further, automatically interpreting from a scanned image to determine not where the lines are, but instead the human's intent and drawing method is a decades-old, challenging problem in computer vision and AI, called "stroke extraction." In the context of handwriting, this problem is called "handwriting trajectory recovery." It is a specialized application, and not one that we advertise as a capability. Very little commercially (or freely) available software currently exists that can perform that task to an appreciable degree of satisfaction.
 
''Aside:'' Going several steps further, automatically interpreting from a scanned image to determine not where the lines are, but instead the human's intent and drawing method is a decades-old, challenging problem in computer vision and AI, called "stroke extraction." In the context of handwriting, this problem is called "handwriting trajectory recovery." It is a specialized application, and not one that we advertise as a capability. Very little commercially (or freely) available software currently exists that can perform that task to an appreciable degree of satisfaction.
 
 
==== Manual Tracing ====
 
 
Aside from using automatic tracing software, you can also ''manually'' trace a scan, in order to produce AxiDraw compatible vector curves. This process is labor intensive, but can also produce extremely high quality output. It is a good method when you need to reproduce ''short'' samples (short notes or a signature) of someone's existing handwriting.
 
 
As an example, suppose that you need to trace an existing (historical) signature, so that it can be printed as a single vector path. You might start with a photograph or scan of the signature. After importing the graphic into Inkscape, use the “pencil” tool to trace along the strokes, and use the additional path editing tools within Inkscape to adjust the strokes until they look proper.  (You can use similar tools and methods within other vector graphics such as Adobe Illustrator or Corel Draw, just as well.)  If you are using Inkscape to do this kind of manual tracing, see "Inkscape settings for handwriting capture" above for some settings that might be helpful.
 
 
With a little practice, this can become quite quick and effective.
 
  
  
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Here are a few possible starting points:
 
Here are a few possible starting points:
* If your goal is to to exactly copy a small number of handwritten notes, a great number of times, and you need to start with a photograph or scan, then consider manually tracing the file, as described above.
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* If your goal is to to exactly copy a small number of handwritten notes a great number of times, then take your scan into Illustrator or Inkscape, and manually trace along the strokes with the pen tool, ideally using a graphics tablet. With a little practice, this can be quite quick. (Additional notes on the topic of direct handwriting capture can be found further up this page.)
 
* If your goal is to generate a great many notes that look reasonably "hand written" but do not need to match someone's exact style, then use regular computer fonts or Hershey-style single-stroke fonts.
 
* If your goal is to generate a great many notes that look reasonably "hand written" but do not need to match someone's exact style, then use regular computer fonts or Hershey-style single-stroke fonts.
 
* If your goal is to digitize signatures, or other very small amounts of text, and do not have to start with scans, then use the jSignature tool discussed earlier or trace the text/signature with a graphics tablet.
 
* If your goal is to digitize signatures, or other very small amounts of text, and do not have to start with scans, then use the jSignature tool discussed earlier or trace the text/signature with a graphics tablet.
 
* If your goal is to reproduce complex artwork that starts as a bitmap image, then you may have no choice but to try and use some kind of bitmap tracing tool.
 
* If your goal is to reproduce complex artwork that starts as a bitmap image, then you may have no choice but to try and use some kind of bitmap tracing tool.

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