Vector vs Bitmap.When creating or editing graphic images there are 2 main types; Vector images and Bitmap images.VectorVector graphics is the creation of digital images, using coordinate which lies on X, Y and sometimes Z axis to create lines and shapes shapes to represent images in a two- dimensional or three- dimensional space. Each element in a vector image can be edited individually for example changing the colour, shape, size and position. Vectors are considered higher quality images as they don’t lose quality when they are enlarged or shrunk down.
The file sizes for vector images are generally small due to the computer only needing to memorise the shape type, size, colour and position.Vectors are used in some food packaging as it can create tiny font sizes without pixelation or loss of quality meaning it may be easier to read the information given. They are also used to create designs which can be printed on clothes, to create animations and for embroidery.The advantages of using vector images is that you get small file sizes due to less information being needed. There is no aliasing which is jagged or pixelated edges around an image. Vectors don’t lose quality when they are stretched or shrunk beyond the original image size making them better for resizing.
As shown in the picture opposite, when the person zooms in on a bitmap image, there would be an appearance of pixelation which causes the appearance of the image to become blurry. However when you look at the vector, no matter how much you zoomed in, the quality will never be lostHowever, there are some disadvantages; Not all image editing software is compatible with creating vector images. An example of some programs which can do this are Adobe illustrator and Adobe Flash.BitmapBitmap images uses the placement of squares in a grid and assign a colour to each square. The squares are known as pixels. This format generally makes two-dimensional images.
This makes more information than using vectors since the computer needs to know every detail of every single pixel therefore the file sizes would be larger. However, most common bitmap file formats use compression to deal with this. When bitmap images are resized, pixelation would occur- this is where the image becomes more jagged around the edges or overall the image becomes blurry. To correct jagged edges many editors use a method called antialiasing where the make the edges fade in colour to the background colour to make the image less pixelated when it is at its native size.The advantages of using bitmap images is that they have more compatibility with more image editing software meaning it is easier to create and edit bitmap images Also the images appear more real due to the complexity of how the pixels are stored. However there are some disadvantages; for example, image quality can be lost when resizing images, the images may appear in larger file sizes due to the computer needing to remember the placement of all pixels. Compression- Lossy vs LosslessCompression is a way of shrinking down file sizes into more suitable and smaller amounts which can be used easier for its intended purposes.
Lossy CompressionLossy compression is a type of file compression that is designed to make the overall file size smaller. This is achieved through partial data discarding which is when the encoding doesn’t recognise the colour of all pixels and only generalises the colours to save data. This means that the image loses sharpness and precision causing the image to appear in a worser quality than initially taken. With lossy compression, you cannot have clear background images, the compression mechanism will give it sometimes a black background but mostly a white one. This is due to it being considered unnecessary for a high compression image and therefore discards the information. JPEG file types support lossy compression.
The picture opposite is an example of high compression, there is little distinction between certain shades of colour used. The background of the image appears more pixelated. The fur looks more fuzzy then it actually is.Compare it to this photo where the cat’s fur is more prominent and easier to see. It is also easier to see the background of the photo than before. The whiskers stick out more and the bed has more separation in colours.
Some people prefer lossy compression to lossless as it produces smaller file sizes so in applications like web graphics it would be more suitable due to lower sizes that the users have to load on their computer making loading timers faster. It is also used in some digital cameras and many phones with cameras when compressing image sizes down so the SD card or the camera’s internal memory could hold more images.Lossless CompressionLossless Compression is a type of file conversion which is designed to keep the file in its original quality after compressing the data. This means the quality of the photo would be higher than that of a photo using lossy compression since it doesn’t delete any data when compressing the file. This type of compression is more suitable for transparent background images since it would retain the data that gives the transparent aspect of the shape.
PNG file types use lossless compression.The image opposite is an example of a lossless compression. The image was placed into an image editing software to show the effect of the transparent background. The software has a white and grey checkerboard pattern to demonstrate there is no background on the image.
Ignore the grey border as that is just the image editing programs background. Some people would prefer lossless compression to lossy as it keeps images in a higher quality and greater level of detail. This means that the images come out sharper and better with more distinction between colour shades and patterns. People making high quality images for posters or cards would prefer this method of compression as the print would come out in better quality after it’s done. Colour Models- RGB vs CMYKA color model, as defined by Google, is a system for creating a full range of colours from a small set of primary colors. When talking about types of colour models, there are 2 types used in the image editing industry; RGB (Red Green Blue) and CMYK (Cyan, Magenta, Yellow, Key/black)RGB- Red Green BlueThe Red, Green and Blue colour model (often referred to as the RGB colour model) is an additive colour model in which the colour are added in various ways to produce a broad array of colours.
Additive colour models is a method of mixing a number of different light colours to produce a new colour.The way a RGB colour mixer in most image editing programs would work is that there is a slider system in which each colour in the model would be given a number to represent its position on their slider. The User can either input numbers into the boxes or use the slider for each colour to produce the colour they want to achieve. The maximum value given in RGB for a component is 255. The new colour would be given a hex code which is an assortment of letters and numbers after a hashtag which represents the combination of the RGB models values. You can copy and paste this into other image editing software if it allows users to input hex codes to gain the colours.RGB is commonly used in web based applications as additive colours are better to work with. Not only that but most devices which will view the information online would read the colours as RGB as they have led lights which emit light according to the RGB mix so a RGB image for web purpose would be slightly better to interpret on a device like a monitor or mobile phone than that using a CMYK colour model.
CMYK- Cyan, Magenta, Yellow, Key (Black)The Cyan, Magenta, Yellow and Key colour model (often referred to as the CMYK colour model) is a subtractive colour model. Subtractive colour models work by mixing a limited set of dyes, inks, paint pigments or natural colourants to create a wider range of colours. The ‘Key’ in CMYK is given to the colour black because in colour printing; cyan, magenta and yellow printing plates are carefully keyed or aligned, with the key of the black key plate.
The way a CMYK colour mixer in most image editing programs would work is that there is a slider system in which each colour in the model would be given a number to represent its position on their slider. The User can either input numbers into the boxes or use the slider for each colour to produce the colour they want to achieve. The maximum value given in CMYK for a component is 100. The new colour would be given a hex code which is an assortment of letters and numbers after a hashtag which represents the combination of the CMYK models values. You can copy and paste this into other image editing software if it allows users to input hex codes to gain the colours.CMYK is commonly used in images that would be printed like vector based graphics.
This is due to it being easier for the printer to interpret the values for the colours as printers use the CMYK colour model for ink. This means the quality of the colour would be better as there doesn’t need to be any interpretation or conversion of what the values may be. This is better in this application to RGB as it uses 4 values so the precision of the colour under printing can be greater than using a RGB colour scheme to print items.
File TypesWhen saving images into formats that can be viewed without having to use image editing software to view them. The software would normally convert the file into a different file format. The most common file formats are; JPEG, BMP and PNG.JPEGJPEG which is short for Joint Photographic Experts Group is a commonly used raster graphics image file format which uses lossy compression to resize the file to a small file size. This is commonly used in compressing images made with digital photography. JPEG files are all bitmap images also known as raster images. JPEG images have the tradeoff between low file sizes for loss in image quality (as explained earlier where I described lossy compression). Using this picture for example, the total file size for it in a PNG format is 402KB compared to the size of a JPEG which is 35.
7 KB. It’s common use is with digital photography and web pages. Due to it using lossy compression it would not be suitable for pictures that need exact reproduction for example logos with clear backgrounds. An advantage of the JPEG file format is the ability to reduce the file size to smaller formats which make it easier to view especially on web mediums where the speed of the connection may determine whether or not the site would take long to load or not.
However a disadvantage of the JPEG file format is that the image would lose any data about transparency. If an image has a transparent background it would be replaced with either a white or black to replace the transparent space.BMPBMP which is short for Bitmap Image File is a raster graphics file format which produces uncompressed images. BMP files are bitmap images (given in the name) also known as raster images. BMP images are uncompressed meaning they have the highest image quality however have the largest file size as result. This means that they become unsuitable for web based applications due to their massive file sizes.
This compared to lossless compression where the size can be reduced without image quality being lost, makes BMP images seem obsolete if we can achieve the same quality after compression without changing the quality of the file.An advantage of using a BMP file format is that it is an uncompressed image meaning it would be the highest quality. This is because no compression is performed on the file meaning the image made is truly what’s been designed. This can create a greater depth and complexity in the image.A disadvantage of this is that the file sizes are much larger than a PNG or JPEG. This is because with compression, file sizes are shrunk so redistribution of the image through web based means is easier than using BMP formats because they take longer to download or load for the user especially if they use slower internet connections.PNGPNG or Portable Network Graphics is a commonly used raster graphics image file format which uses lossless compression to resize the file to a small file size.
This form of compression (lossless) is different from lossy compression as data is not discarded when the image is being resized. This means that the image remains a high quality, not as high as a uncompressed BMP file but higher than a JPEG file. PNG graphics files are bitmap graphics files otherwise known as raster graphics files.
This is an example of a PNG graphic, it uses lossless compression which shows a transparent background represented on the image editing software with a white and grey background.An advantage of using PNG formats is that it has a higher image quality than JPEG. This is because PNG uses lossless compression which doesn’t subtract data whereas lossy compression has partial data discarding which means that data which is deemed unnecessary in creating a smaller file size gets deleted. This means there is more complexity with the overall product.However there is a disadvantage of using this type of file is that it is a large file size.
Not as large as the bmp file format but larger than JPEG files.
