Bitmap And Vector
Suheil
Bitmap
A set of bits that represents a graphic image, with each bit or group of bits corresponding to a pixel in the image.
Bitmap
A set of bits that represents a graphic image, with each bit or group of bits corresponding to a pixel in the image.
Vector
Vector graphics is the use of geometrical primitives such as points , lines , curves , and shapes or poygons
GIF
The Graphics Interchange Format (better known by its acronym GIF is a bitmap image format.
JPEG
JPEG - named after its creator the Joint Photographic Expert Group, is a commonly used method of lossy compression for digital photography
TIFF
TIFF (originally standing for Tagged Image File Format)
is a file format for storing images, popular among graphic artists, the publishing industry, and both amateur and professional photographers in general.
PNG
Portable Network Graphics is a raster graphics file format that supports lossless data compression. PNG was created as an improved, non-patented replacement for Graphics Interchange Format (GIF),
Advantages and Disadvantages Of GIF
Gif - Disadvantages -
Low color palette:
One of the largest downfalls to the GIF format is its inability to have a color palette of more than 256 colors. This can create poor looking images when used on a photograph which may originally have thousands of different colors. -
Lower level of transparency:
As we discuss below, PNG has a much higher level of transparency support. GIF do not provide full transparency as is offered by PNG images. -images.
Patent Restrictions:
GIF has patent restrictions with it’s use.
Let us now see how the GIF images use lossless compression and where they can be best used.-
Lossless Compression
GIF uses lossless LZW compression, effective on indexed color. The format is loss-less, meaning it does not get blurry or messy. GIFs use a simple technique called LZW compression to reduce the file sizes of images by finding repeated patterns of pixels, but this compression never degrades the image quality.
Advantages -
Graphics in GIF format, or GIFs, are recommended when the images contain only a few distinct colors, such as line drawings, logos, or even black and white images. An example of a GIF would be "logo.gif."
Graphics with this file format are typically small in size, and therefore download and dispAnother advantage of using GIFs is that you can make their background transparent so that the background color of the Web page shows through.lay faster.
Advantages and Disadvantages Of JPEG
Advantages of JPEG-
JPEG files can be opened and viewed in almost all image viewing applications.The JPEG format is also compatible with all printers, allowing users to print JPEG files directly from the viewing application without having to change its format. JPEG is also compatible with practically every photo editing software, though the files often need to be saved to another format to save the alterations.. JPEG images are stored quickly by cameras and other devices. This allows users to capture fast moving action with a JPEG image that would be blurry in a higher resolution image. JPEG is often set as the default file format for digital cameras to enable them to take pictures quickly.
Disadvantages of JPEG-
When image files are converted to the JPEG format, significant amounts of information about the image are lost.The compression method is actually called the lossy compression technique. In essence, JPEG images are lower quality than other formatsJPEG is not suited for images that will be radically modified, since detail is lost each time the image is saved. Another limitation of JPEG is that it does not support layers, a problem for those who want to touch up or alter images.
Advantages and Disadvantages Of Tiff
Advantages-
One of the major advantages of TIFF files is that they can be edited with most popular image editing software on the market. All popular operating systems have built-in TIFF viewers.By default, TIFF files do not use compression. The big advantage to this is that there is no loss of image detail when a save is made.
Disadvantage-
Since compression is not used by default on TIFF files, the file size is generally quite big. This is a big disadvantage of TIFF files. Uncompressed TIFF images can take up a lot more space than a JPEG. In comparison to other imaging file formats, TIFF's are not as commonly used due to their large file size. In most cases, TIFF's will be used until a final save is required, this is often done as JPEG format to greatly reduce the file size.
Advantages and Disadvantages Of PNG
Advantages
Lossless compression
As we have studied in the previous article that JPEG images use the lossy compression and the GIF images use the LZW compression technique. However in contrast to both of them the PNG format uses ZIP compression which is lossless, and slightly more effective than LZW (slightly smaller files).
48-bit, true-color depth
PNGs are palette-based, with file size related to bit depth, or the number of colors contained in the palette. In general we can say that in case of PNG images you can use the lowest bit depth that creates an acceptable image. The quality of images and their colors are retained in PNG images.
Disadvantages
Interlacing
The way the images show up on the monitor screen of the viewer is also of great importance. JPEG accomplishes this with a top to bottom progressive display while PNG can use an interlacing scheme. If a PNG is not interlaced it is viewed progressively. PNG interlacing (formally known as Adam 7) begins by only reading a small percentage of all the data and filling in the empty spaces with an interpolated color value. The GIF format can also be interlaced, but the quality is not nearly as good, or fast as a PNG as GIF in
Browser support
Although the PNG images support alpha channels but the unfortunate thing with alpha in PNG’s is that browser support is way behind the times, although slowly catching up. IE6 doesn’t support alpha-channels. Once a new version of IE comes out with this vital support, you should see the effect springing up on trendy designers’ sites across the web.terlacing is only one-dimensional.