Vector vs Bitmap

Today we are going to learn in a hands on way about vector image files verses bitmap image types.

The scenario is that you've found this small image and want to use it covering the full screen.


The screen you are on has 1024 pixels wide and 768 pixels tall,  to make this pumpkin image fill the whole screen you need to re-size it to around 1000 wide, lets do that and see what happens.


If you download and use the Bitmap image file, as you scale the image larger it will look blotchy or blurry.

Basically a bitmap image is made up of pixels, tiny dots that made the picture show, this pumpkin image has a pixel definition or size of 150 pixels or dots wide by 137 tall that is quite small and would be considered a low resolution image.
As the individual pixels times by 6 (150 x 6.66 = 999) they will duplicate over and over six times so that the original pixels that made the image are in the same places relational to each other just larger on the screen.

This process is called Pixelization.

Lets do this so that it makes a little more sense.

First load the program Inkscape
(Start > Programs > Inkscape)

Second download this image and open it in Inkscape, or copy and paste this image into Inkscape:

Then export the bitmap (File > Export Bitmap) and set the width to 1000.

Save to Y drive, give it a name, then go look at the image and see what you think of it.

Vector images are geometrical primitives such as points, lines, curves or shapes which the computer makes based on mathematical expressions that represent images. These mathematical expressions are not connected to exact pixels like a bitmap is so that if you want the shape larger or smaller the computer can simply multiply the math that makes that image to get a larger image. Let's try it out and see..

This time while in Inkscape click Path > Trace Bitmap.  Then click Ok.    (This will turn the bitmap into a vector)

Next select and move the pumpkin vector away from the pumpkin bitmap. 

With the vector selected you can change the color if you want, other wise simply export it as a bitmap to Y drive, with the width 1000 pixels again and go compare it with the first.

Compare the two images that are in your Y drive, maybe have them named bitmap.png and vector.png.

If you would like you can turn them into me, but mostly I just want to see that you completed this exercise so that we can build on this concept in later assignments.


password: lane

http://dropitto.me/lane <- click this to upload completed file.