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

Title of script: Trace bitmap in Inkscape

Author: Arthi. A & Saurabh

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 the 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 0.91
Show the images	The images used as examples in this tutorial, have been provided in the Code File link. Pause the tutorial here and download the images on your machine.
Show the images	Here are the 2 images on my desktop. Let me open them.
Point to the images	Linux_raster.png is the raster image and Linux_vector.png is the vector image.
Zoom into both the images	Both the images may look similar. We will know the difference only by zooming into the image. Let's do so.
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 that 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.
Open Inkscape	Open Inkscape. Now, we will import the raster image.
Go to File >> Import	Go to File and click on Import.
Path menu >> Trace Bitmap	Now, go to Path menu and 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, check the Live Preview option to observe the changes.
Point to Preview window	As you can see in the Preview window, Brightness steps finds the difference in brightness.
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 it looks 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 similar to 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	I will choose Colors options by clicking 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 one side in order to see both 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 mentioned earlier the first image gets pixelated, while the second one does not gets pixelated. And we can also see the paths very clearly.
Delete the original image	Now, delete the original image.
Point to the image >> Click on Nodes tool	We will now learn to edit the vector image. To do so, click on the Nodes tool.
Add nodes on the head area	Let us add some hair style. Add nodes on the head area. Now move the nodes a little up, as demonstrated.
Point to the image	Next let us change the colors of the image.
Change the colors	You can change the colors according to your imagination.
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, that is, in PDF format. Go to File and then click on Save As.
PDF >> Image-vector	Change the extension to PDF and name it as Image-vector.
Point to the image	Next let us save the image as raster, that is, in PNG format.
File >> Save As	Once again, go to File and click on Save As.
Save the image as PNG	Now change the extension to PNG and 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 the 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 in greyscale.
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