Common file formats

Common file formats

1. PNG Files - stands for portable network graphics. These files use comperssion that doenst result in loss of quality. It uses 16 million colours but the resulting file size is larger than GIF or JPEG.

   • advantages- Lossless compression of PNG images means that no image data is lost when saving or viewing the image. This results that there is no loss in the quality of the image when image is saved again and again in PNG image format.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.in PNG images an alpha channel is supported. An alpha channel can specify the opacity of any pixel from 0–255, where 0 is fully transparent and 255 is fully opaque. This allows you to create a graphic that has no background. Such an image can be placed on top of any other background and will retain a translucent effect, with the background showing through the pixels that are not opaque.
   • disadvantages- The PNG images also do not support animation. PNG fileformat does not compress photographic content very well, old versions of Internet Explorer did not properly support semitransparent PNG images without a convoluted work-around

2. BMP Files- This file format save the image as a map of pixels. It supports millions of colours but because of the very large file size the time taken to load the file from the Internet is large.

   • advantages- BMP files are especially useful for the storage of complex, real-world images. Intricate images, in conjunction with photographic equipment and video elements, can be easily stored in BMP format. BMP files store each pixel (or dot of colour) independently, therefore maintaining the accuracy and quality of the stored image. The BMP file format is universal and can be used with almost any program
   • disadvantages- They are memory intensive, so the higher the resolution the larger the file will be. BMP images are large files that require a lot of storage space because no effort is made to reduce the file size. BMPs aren't really suitable for Macintosh computers or the web.

3. EPS FIles- Stands for Encapsulated PostScript and is standard format for importing anf exporting PostScript files. EPS can contain text, graphics and images and contain a small preview image.

   • advantages- it does not require the computer to be equipped with Japanese fonts. This means you can send an EPS file to virtually any printing bureau to print your documents.EPS files are considered an ideal format for importing into computer graphics applications. EPS file format makes curved lines re-sizable too without degrading the quality.
   • disadvantages- The main drawback of EPS files is the fact that you need to have mostly Adobe products and PostScript printers to work on EPS filesthe files can be very large. Several megabytes is not untypical.Although EPS files are supported by most graphic design programs, page layout applications don't usually support modification of an EPS file's text, lines or colouration,

4. TIFF- This stands for Tagged Image File Format. TIFF is bitmapped image format and is ideally suited to scanned images, images with continuous colours and photographs. TIFFs are widely used and can be easily modified and can have a number of colours.

   • advnatages- a TIFF file can be compressed to reduce the file size, while still maintaining a high degree of image detail. Alternatively, it can be saved without compression to retain 100 per cent of the original image taken - where each pixel is identical to the original image taken. Like a GIF, you can also save it with a transparent background.
   • disadvantages- Good specification computer needed to process and load images. Most website and online images galleries do not support tiff uploading. Slow speeds when transferring to online galleries that do support TIFF files

5. PSD- Stands for PhotoShop Document. Photoshop ia a popular piece of software used for creating and modifying images. PSD file fomrat produces very high quality images but as there is no compression, the filse sizes are large. so they would take a while to upload and download on the internet.

   • advantages-can handle simple vector layers making them more suitable for importing and exporting data from programes like adobe illistrator. PSD files’ large size and capability to save significant amounts of file information make them an excellent choice for working files. PSD use lossless compression so quality of image is not lost.
   • Disadvantages-PSD files tend to be extremely large, since these lossless images use no compression. This preserves all image information, but can make the file itself unwieldy and difficult to email or transfer. The PSD format is a proprietary Adobe file format. The company does not release its specifications to the general public. PSD support is often inconsistent outside of Adobe’s products

6. JPEG- Stands for joint photographic expert group. it uses 24 bits of colour. JPEG is ideal for photographs and many didigatl cameras automatically ceate files with this file format. Like GIF, JPEG, compresses the original image.

   • advantages- Doesn’t take up much storage space. this format supported by every image editor and web browser on the market. It is also supported by every digital camera, and any video camcorder that can also take pictures. Every digital photo print shop also supports the JPEG standard. Photos are typically made up of thousands or even millions of colors. The JPEG format can handle that many colors as well as keep the file size to a minimum.
   • Disadvantages-The compression algorithm is “lossy”, which means data is discarded when the file is compressed. The more compression you use, the more artifacts may appear. These usually look like “smudges” in the image, and can really reduce the quality of the image. All the settings from the digital camera have already been applied to the JPEG. This can be a downside if, for example, you had the wrong colour balance set, then your digital pictures would have a colour cast to them.

7. GIF- stands for graphical interchange format and along witht the file format called JPEG, it is one of the two main file formats used for imagesused on the internet.

   • advantages- It is ideal for images that have large blocks of a single colour, and it can support up to a maximum of 256 colours. Unlike with JPGs, it is possible to alter the background colour of a GIF to make it transparent. This makes it possible to place it over other images or on webpages.
   • disadvantages- limited colour support, files often not as small as PNG, does not support full transparency (alpha channels)