How to convert bitmap (raster) image to vector image by Illustrator
Bitmap use point to form an image. The point is called pixel. When enlarge the bitmap image, it will become blurry and unclear.
Vector use mathematic equation to record all lines (including curves, point and shape). The lines call paths. When enlarge the image, it will re-calculate and re-draw all lines. So the image can remain clear and smooth.
Illustrator is a popular software for making and editing vector graphic.
To convert a bitmap image to vector image is called vectorize or vectorization.
To convert a vector image to bitmap image is called rasterize or rasterization.
In illustrator, there is a tool called "Image Trace" which can turn bitmap image to vector image easily.
Below is a tutorial of how to convert a bitmap image into a vector image in Illustrator.
Select the bitmap image that you want to change to vector.
Menu > Windows > Image Trace.
Open the "Image Trace" window.
Preset: "Black and White Logo"
Select "Preview" at the left bottom.
Now you can already preview the vector image.
If the vector image is not good enough, you can fine tune it by adjusting the setting in "Image Trace".
If the image is okay, press the "Expand" button on the tool bar on top.
After pressing the "Expand" button, the convertion is finished.
If you want to edit the image, click the right button of the mouse, select "ungroup".
Bitmap and Vector
Bitmaps are raster image files that use a grid made up of pixels. Each pixel has its own color information, and when the pixels are combined, they create an image. When a bitmap is enlarged, the pixels become larger and more visible, giving the image a grainy texture. Vector images are defined by paths, not pixels, so resizing one has no effect on the image quality.
Convert raster images like PNGs, BMPs and JPEGs to vector graphics.
A Raster graphics image is a rectangular grid of pixels, in which each pixel (or point) has an associated color value. Changing the size of the raster image mostly results in loss of apparent quality.
Vector graphics are not based on pixels but on primitives such as points, lines, curves which are represented by mathematical expressions. Without a loss in quality vector graphics are easily scale- and rotateable.
Convert JPG, PNG, GIF Images to Vectors
Bitmap images vs Vector images
Vector images consist of shapes like circles, rectangles, lines and curves, while bitmap images, also known as raster images, consist of a grid of pixels. Vectorization or tracing is the process of taking a bitmap image and re-drawing it as a vector image.
The shapes in vector images allow computers to do things that cannot be done with bitmap images, like scale them to any size without loss of quality and using them to e.g. cut, sew, paint, and laser engrave.
Bitmap image file formats
One of the most widely-used image formats. It has excellent compression characteristics and has the nice feature that the user may specify what level of compression they desire, trading off fidelity for file size.
We do not recommend using JPEG files for rasterized vector art, as the compression artifacts substantially degrade the quality of the image near edges.
The best of the lossless image formats is called PNG (Portable Network Graphics). This format is widely supported by web browsers and image viewers/editors.
There are actually several BMP formats (BitMaP). Windows and Macintosh have their own formats, both of which are called BMP. Most modern image editing tools are able to read both.
In any case, all of the variants of BMP should be avoided when possible, as they use little to no compression and consequently have unnecessarily large file sizes.
Vector image file formats
Adobe's EPS format (Encapsulated PostScript) is perhaps the most common vector image format. It is the standard interchange format in the print industry. It is widely supported as an export format, but due to the complexity of the full format specification, not all programs that claim to support EPS are able to import all variants of it. Adobe Illustrator and recent versions of CorelDRAW have very good support for reading and writing EPS. Ghostview can read it very well but does not have any editing capabilities. Inkscape can only export it.
The W3C standard vector image format is called SVG (Scalable Vector Graphics). Inkscape and recent versions of Adobe Illustrator and CorelDRAW have good support for reading and writing SVG. Further information on the SVG format may be found on the official SVG website.
Adobe's PDF format (Portable Document Format) is very widely used as a general purpose platform-independent document format. And while it is not exclusively used as such, it is also a very good vector image format. Adobe gives away the Acrobat PDF reader, but sells the tools required to create PDF files (third party tools that perform the same task are also for sale). Those tools work with any program that is able to print. Support for reading and editing PDF files is much more limited.
The native format of Adobe Illustrator is the AI format (Adobe Illustrator Artwork), a modified version of the older EPS format. The AI format is fairly widely supported, but is less ubiquitous than the EPS format, and most programs that read AI can also read EPS.
Drawing eXchange Format. A CAD format from Autodesk, used by CAD tools from many different vendors. Some programs have difficulty reading DXF files with splines (curves), so the Desktop Edition supports line+spline as well as line only output modes.