There are many different types of images, and each type has its advantages and disadvantages depending on what you want to do with it, but before we get onto image types you need to understand how a picture on a computer is made up.
This blog post gives you an overview of the different types of image files.
Pixels
Pixels are the smallest part of an image, each pixel stores details about how much red, green and blue is in it (RGB) as computers make every colour through a combination of red, green and blue.
Pixels are square and they make up your computer screen. When you change the resolution of your computer screen you are changing how many pixels there are on the screen. The more pixels there are on your screen or in your image the better quality the image will look. The less pixels you have the more blocky your images will look (like Mario!)
Lossy vs Loss less file types
Sometimes image files can be pretty big so they will take up a lot of memory on your computer. In order to reduce the file size some kind of compression is needed.A lossy file type will lose some of the image quality as the file size is compressed. A loss less file type will keep all of the details in the image – creating a perfect copy.
Types of image compression (file types)
JPEG
JPEG stands for Joint Photographic Experts Group. This type of image compression is lossy, and it is commonly used in digital cameras and scanners. With JPEG images you can specify the quality of the image, obviously the higher the quality the larger the file size but it will also result in a higher quality image. The quality of a JPEG file can be reduced if it is edited heavily.
JPEG stands for Joint Photographic Experts Group. This type of image compression is lossy, and it is commonly used in digital cameras and scanners. With JPEG images you can specify the quality of the image, obviously the higher the quality the larger the file size but it will also result in a higher quality image. The quality of a JPEG file can be reduced if it is edited heavily.
GIF
GIF (Graphics Interchange Format) images are limited to 255 colours. GIFs are commonly used for logos and simple images which do not have a lot of colours in them. GIF images can also be animated. The type of compression is loss less.
GIF (Graphics Interchange Format) images are limited to 255 colours. GIFs are commonly used for logos and simple images which do not have a lot of colours in them. GIF images can also be animated. The type of compression is loss less.
TIFF
TIFF stands for Tagged Image File Format. TIFF images can be both lossy and loss less. TIFF files remember a lot of information about the image, so they can be quite big however they are usually quite a good quality.
TIFF stands for Tagged Image File Format. TIFF images can be both lossy and loss less. TIFF files remember a lot of information about the image, so they can be quite big however they are usually quite a good quality.
PSD
This is a Photoshop image file. It remembers all of the details about all the changes you have made to the image and so these files are usually pretty big.
This is a Photoshop image file. It remembers all of the details about all the changes you have made to the image and so these files are usually pretty big.
RAW
This type of image is what photographers use. When you take a photograph in RAW format, the camera records all of the details which were present at the time, this means that the file sizes are massive and totally loss less, however RAW images are very easy to manipulate.
This type of image is what photographers use. When you take a photograph in RAW format, the camera records all of the details which were present at the time, this means that the file sizes are massive and totally loss less, however RAW images are very easy to manipulate.
Vector images
These images are made up of mathematical formulas which work out the position of the different elements (shapes or objects) in the image. This means that when you zoom into a vector image it remains a good quality because the image is recalculated using the formulas. Due to the formulas and shapes being saved rather than individual pixels the file size for vector images can be small. Vector images normally look cartoon like, and are created from scratch on a computer.
These images are made up of mathematical formulas which work out the position of the different elements (shapes or objects) in the image. This means that when you zoom into a vector image it remains a good quality because the image is recalculated using the formulas. Due to the formulas and shapes being saved rather than individual pixels the file size for vector images can be small. Vector images normally look cartoon like, and are created from scratch on a computer.
Raster / Bitmap images
Bitmap images are made up of binary code – each pixel is either switched on or off. As the image needs to store details about each and every pixel, the file size for these types of graphics are normally quite big. When you use a digital camera or a scanner you are usually creating a bitmap image. When you resize a bitmap image you lose quality from the image and the closer you zoom in, the more obvious each individual pixel will become. As you can see each individual pixel, each pixels can be edited.
Bitmap images are made up of binary code – each pixel is either switched on or off. As the image needs to store details about each and every pixel, the file size for these types of graphics are normally quite big. When you use a digital camera or a scanner you are usually creating a bitmap image. When you resize a bitmap image you lose quality from the image and the closer you zoom in, the more obvious each individual pixel will become. As you can see each individual pixel, each pixels can be edited.
No comments:
Post a Comment