Inkscape/C4/Trace-bitmaps-in-Inkscape/English

From Script | Spoken-Tutorial
Revision as of 17:02, 4 September 2015 by Arthi (Talk | contribs)

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search

Title of script: Trace bitmap in Inkscape

Author: Arthi. A

Keywords: Difference between raster and vector image, various raster and vector formats, convert raster image to vector


Visual cue
Narration
Opening Slide Welcome to the Spoken Tutorial on “Trace bitmap in Inkscape” using Inkscape.
Learning Objectives (Slide) In this tutorial

We will learn to

  • Difference between raster and vector image
  • Various raster and vector formats
  • Convert raster image to vector


System requirement (Slide) To record this tutorial, I am using
  • Ubuntu Linux 12.04 OS
  • Inkscape version 0.48.4


Show the images Here are 2 images on my desktop.


Let me open them.



Open the images The first is the raster image and the second image is vector.



Zoom into both the images Both the images may look similar.


You can find the difference by zooming into the image.



Point to the first image Now the first image looks pixelated because a raster image is made of up pixels.



Point to the second image But the second image does not pixelate because a vector image is made up of paths.



Raster image formats (Slide) Some of the raster image formats are


  • JPEG
  • PNG
  • TIFF
  • GIF
  • BMP
    etc


Vector image formats (Slide) Some of the vector image formats are


  • SVG
  • AI
  • CGM
    etc


Compound formats The formats which can be both vector and raster are


  • PDF
  • EPS
  • SWF

<<PAUSE>>



Point to both the images Let us now learn how to convert this raster image to vector.



Slide This image is given to you in the code files link.


<<PAUSE>>

Open Inkscape Open Inkscape. Let us Import the raster image now.



Go to File >> Import Go to File. Click on Import.



Path menu >> Trace Bitmap Now, go to Path menu. Click on Trace Bitmap.



Point to the dialog box A dialog box opens up. Under the Mode tab we can see various options.



Point to the image Make sure the image is selected.
Point to the Brightness cutoff option By default Brightness cutoff option is selected.

Under Preview, click on Update button to observe the changes.

Point to Preview window As you can see in the Preview window, Brightness steps finds the difference in brightness.



Point to Update button Make sure to click on the Update button after selecting each option.
Click on Edge detection Now click on the second option, that is Edge detection.

As the name indicates it finds only the edges.

Click on Color quantization Color quantization traces along the boundaries of reduced colors.
Click on Invert image Invert image will invert the colors of the bitmap if you think the is better inverted.
Click on Multiple scans Multiple scans is good for multiple colors.
Click on Brightness cutoff Once again Brightness steps finds the difference in brightness.
Click on Colors Colors finds an amount of colors specified.



Click on Grays Grays is like colors, but finds only grayscale colors.
Point to Smooth option Smooth applies Gaussian blur to the bitmap before tracing.



Point to Stack scans Stack scans will stack scans on top of another instead of tiling.

This eliminates gaps.

Point to Remove Background Remove Background will take the background away. Let me click on it.



Point to the dialog box Now we have seen all the tracing options.

You can choose from any of these according to your requirement.

Click on colors option Let me choose colors options. Click on it.
Click on OK >> Close the dialog box Now click on OK and close the dialog box.
Point to the traced image The traced image in created on the top of the original image.
Click and move the image Click and move the image to see both of the images.
Zoom in to the images The image is now converted into raster.


Zoom in to the images.



Point to both the images As told earlier the first image gets pixelated, while the second one does not gets pixelated and you can see the paths clearly.



Delete the original image Delete the original image.
Point to the image >>

Click on Nodes tool

Now we can edit the vector image.

To do do, click on the Nodes tool.

Add 2 nodes on the head area Let us add some hair style.

Add 2 nodes on the head area. Now move the nodes little up.

Star tool >> draw stars Next click on the star tool and draw stars on the stomach area.
Point to the image Next let us change the colors of the image.
Change the colors Let me change the black color to blue.


Eyes color to green and the stomach area to pink.

Point to the image Let me now save the image in both raster and vector formats.



Save the image as PDF First save it as vector. So in a PDF format.


Go to File. Click on Save As.



PDF >> Image-vector Change the extension to PDF. Name it as Image-vector.
Point to the image Next let us save the image as rater, that is in a PNG format.
File >> Save As Once again go to File. Click on Save As.
Save the image as PNG Now change the extension to PNG. Click on Save.

Change the name as Linux-raster.

Open both the images Now let us go to the desktop and check both the images.
Point to both the images Now you can clearly identify the difference between the two images.
Summarize That's all for this tutorial. Let us summarize.

In this tutorial, we have learnt to

  • Difference between raster and vector image
  • Various raster and vector formats
  • Convert raster image to vector



Assignment As an assignment, select a vector image and convert to a raster of grey color.
About Slide The video available at the following link summarizes the Spoken Tutorial project. Please watch it.
About Slide The Spoken Tutorial Project Team conducts workshops and gives certificates for those who pass an online test.

For more details, please write to us.

About Slide Spoken Tutorial Project is supported by the NMEICT, MHRD, Government of India.

More information on this Mission is available at this link.

Acknowledgment We have come to the end of this tutorial.

This is Arthi and Saurabh from IIT Bombay, signing off. Thanks for joining.

Contributors and Content Editors

Arthi, Nancyvarkey