Support

What Are Bitmap Images?

A bitmap is a type of memory organization or image file format used to store digital images. The term bitmap comes from the computer programming terminology, meaning just a map of bits, a spatially mapped array of bits. Now, along with pixmap, it commonly has a similar concept to that of a spatially mapped array of pixels. Raster images in general may be referred to as bitmaps or pixmaps, whether synthetic or photographic, in files or memory.
Bitmap images refer to those described by pixels - squares of color arranged in a grid.

View more about bitmap images ›

In computing, a bitmap is a mapping from some domain (for example, a range of integers) to bits, that is, values which are zero or one. It is also called a bit array or bitmap index.
In computer graphics, when the domain is a rectangle (indexed by two coordinates) a bitmap gives a way to store a binary image, that is, an image in which each pixel is either black or white (or any two colors).
The more general term pixmap refers to a map of pixels, where each one may store more than two colors, thus using more than one bit per pixel. Often bitmap is used for this as well. In some ways, the term bitmap implies one bit per pixel, while pixmap can be used for images with multiple bits per pixel.
For built-in graphics subsystems, many graphical user interfaces apply bitmaps; for instance, the Microsoft Windows and GDI subsystem of OS/2 platforms, where the specific format used is the Windows and OS/2 bitmap file format, usually named with the file extension of .BMP (or .DIB for device-independent bitmap). Besides BMP, other file formats that store literal bitmaps include InterLeaved Bitmap (ILBM), Portable Bitmap (PBM), X Bitmap (XBM), and Wireless Application Protocol Bitmap (WBMP). Similarly, most other image file formats, such as JPEG, TIFF, PNG, and GIF, also store bitmap images (as opposed to vector graphics), but they are not usually referred to as bitmaps, since they use compressed formats internally.

View more in Wikipadia

What Are Vector Graphics?

Vector graphics is the use of polygons to represent images in computer graphics. Vector graphics are based on vectors, which lead through locations called control points or nodes. Each of these points has a definite position on the x and y axes of the work plane and determines the direction of the path; further, each path may be assigned various attributes, including such values as stroke color, shape, curve, thickness, and fill.

View more about vector graphics ›

One of the first uses of vector graphic displays was the US SAGE air defense system. Vector graphics systems were only retired from U.S. en route air traffic control in 1999, and are likely still in use in military and specialised systems. Vector graphics were also used on the TX-2 at the MIT Lincoln Laboratory by computer graphics pioneer Ivan Sutherland to run his program Sketchpad in 1963.
Subsequent vector graphics systems, most of which iterated through dynamically modifiable stored lists of drawing instructions, include the IBM 2250, Imlac PDS-1, and DEC GT40. There was a home gaming system that used vector graphics called Vectrex as well as various arcade games like Asteroids, Space Wars and many cinematronics titles such as Rip-Off, and Tail Gunner using vector monitors. Storage scope displays, such as the Tektronix 4014, could display vector images but not modify them without first erasing the display.
In computer typography, modern outline fonts describe printable characters (glyphs) by cubic or quadratic mathematical curves with control points.[3] Nevertheless, bitmap fonts are still in use. Converting outlines requires filling them in; converting to bitmaps is not trivial, because bitmaps often don't have sufficient resolution to avoid "stairstepping" ("aliasing"), especially with smaller visible character sizes. Processing outline character data in sophisticated fashion to create satisfactory bitmaps for rendering is called "hinting". Although the term implies suggestion, the process is deterministic, and done by executable code, essentially a special-purpose computer language. While automatic hinting is possible, results can be inferior to that done by experts.
Modern vector graphics displays can sometimes be found at laser light shows, where two fast-moving X-Y mirrors position the beam to rapidly draw shapes and text as straight and curved strokes on a screen.
Vector graphics can be created in form using a pen plotter, a special type of printer that uses a series of ballpoint and felt-tip pens on a servo-driven mount that moves horizontally across the paper, with the plotter moving the paper back and forth through its paper path for vertical movement. Although a typical plot might easily require a few thousand paper motions, back and forth, the paper doesn't slip. In a tiny roll-fed plotter made by Alps in Japan, teeth on thin sprockets indented the paper near its edges on the first pass, and maintained registration on subsequent passes.
Some Hewlett-Packard pen plotters had two-axis pen carriers and stationery paper (plot size was limited). However, the moving-paper H-P plotters had grit wheels (akin to machine-shop grinding wheels) which, on the first pass, indented the paper surface, and collectively maintained registration.
Present-day vector graphic files such as engineering drawings are typically printed as bitmaps, after vector-to-raster conversion.
The term "vector graphics" is mainly used today in the context of two-dimensional computer graphics. It is one of several modes an artist can use to create an image on a raster display. Other modes include text, multimedia, and 3D rendering. Virtually all modern 3D rendering is done using extensions of 2D vector graphics techniques. Plotters used in technical drawing still draw vectors directly to paper.

View more in Wikipadia

Why Use Vector Images?

An image does not have any structure: it is just a collection of marks on paper, grains in film, or pixels in a bitmap. While such an image has its way, it has some limits. If the image is magnified to an extent, its artifacts will appear. The halftone dots, film grains and pixels become apparent. Images of sharp edges become fuzzy or jagged. See, for example, pixelation.
To the contrary, a vector image does not have the same problem. Edges are represented as a mathematical lines or curves, and they can be magnified thousands of times — until the precision of the numbers becomes an issue.

View more about the uses of vector images ›

Vector images are used in most aspects of graphic design and are the preferred format for printing, both on paper and on clothes. The reason for this is that while a bitmap image can look great on the screen, which usually has a resolution of about 72 pixels/dots per inch (DPI), it will normally have to be scaled by a factor of 8 or more when printed since modern printers routinely produce resolutions of 600 pixels/dots per inch. Vector images can handle this type of scaling without any problems while bitmap images struggle with it.
Many forms of printing require vector input in order to work - flex printing and embroidery for example.
Vector images are also used on the web in for example flash animations..

What Is Tracing? Vectorization?

In computer graphics, image tracing, raster-to-vector conversion or vectorization is the conversion of raster graphics into vector graphics.
Vectorization starts with an image which can be vectorized manually by hand or be done automatically by various computer pograms.

View more about image tracing ›

The task in vectorization is to convert a two-dimensional image into a two-dimensional vector representation of the image. It is not examining the image and attempting to recognize or extract a three-dimensional model; it is not a vision system. For most applications, vectorization does not involve optical character recognition; characters are treated as lines, curves, or filled objects without attaching any significance to them. An advantage is that the shape of the character is preserved, so artistic embellishments remain.
Continuous tone photographs (such as live portraits) are not good candidates for vectorization. Synthetic images such as maps, cartoons, logos, clip art, and technical drawings are candidates for vectorization. Those images could have been originally made as vector images because they are based on geometric shapes or drawn with simple curves.
The input is an image, but that image may be in many forms such as a photograph, a drawing on paper, or one of several raster file formats. Programs that do raster-to-vector conversion may accept bitmap formats such as TIFF, BMP and PNG.
The output is a vector file format. Common vector formats are SVG, DXF, EPS, EMF and AI.
Vectorization is used to update images or recover work. Personal computers often come with a simple paint program that produces a bitmap output file. These programs allow users to make simple illustrations by adding text, drawing outlines, and filling outline with a specific color. Only the results of these operations (the pixels) are saved in the resulting bitmap; the drawing and filling operations are discarded. Vectorization can be used to recapture some of the information that was lost.
Vectorization is also used to recover information that was originally in a vector format but has been lost or has become unavailable. A company may have commissioned a logo from a graphic arts firm. Although the graphics firm used a vector format, the client company may not have a copy of that format. Later, the company may get a vector format by scanning and vectorizing a paper copy of the logo.
The image can be vectorized manually. A person could look at the image, make some measurements, and then write the output file by hand. That was the case for the vectorization of a technical illustration about neutrinos. The illustration has a few geometric shapes and a lot of text; it was relatively easy to convert the shapes, and the SVG vector format allows the text (even subscripts and superscripts) to be entered easily.
The original image did not have any curves (except for the text), so the conversion is straightforward. Curves make the conversion more complicated, so computers are often used in the process. Vectorization often needs a computer to manage the vector data.
If the image is not in machine readable form, then it is scanned into a usable file format.
Automated programs can have mixed results. Our program is used to convert a PNG map to SVG. The program did a good job on the map boundaries (the most tedious task in the tracing) and the settings dropped out all the text (small objects).

What Is SVG?

SVG is a vector editing software for 2D graphics that are dependent on XML and supports interaction and animation. In XML text files, SVG pictures and their functionality are described. Because SVG files are simply XML files, they may be modified with any text editor. SVG files are supported by all current web browsers, and their markup may be rendered by them.

The task in vectorization is to convert a two-dimensional image into a two-dimensional vector representation of the image. It is not examining the image and attempting to recognize or extract a three-dimensional model; it is not a vision system. For most applications, vectorization does not involve optical character recognition; characters are treated as lines, curves, or filled objects without attaching any significance to them. An advantage is that the shape of the character is preserved, so artistic embellishments remain.
Continuous tone photographs (such as live portraits) are not good candidates for vectorization. Synthetic images such as maps, cartoons, logos, clip art, and technical drawings are candidates for vectorization. Those images could have been originally made as vector images because they are based on geometric shapes or drawn with simple curves.