Discuss the impact that file format, compression techniques image resolution and colour depth have on file size and image quality. In this report, I will talk about my understanding of the impact in various file format, the different compression techniques, and different resolutions and different colour depth. I will show print screens of different types of compression techniques, megapixels under image quality & resolution and three different types of colour depths. I will explain the reasons why some are larger compared to others.
The format includes PSD, JPEG, TIFF, BMP and GIF. I will also go into detail why colour depths will affect the quality of the final output that the file has created. File formats: As you know, there are 5 different types of file formats that you could find when saving an image or when looking up an image under at the end of the title named under PSD, JPEG, TIFF, BMP, and GIF. However, I will explain four basic formats and they are PSD, JPEG, TIFF and GIF as BMP is used under GIF. Here are the types of formats and explanations of them:
* PSD format- The format PSD is used within Adobe Photoshop and this format is a default format for this software that allows saving the edited graphical images automatically to this specific format and also edit and/or change specific layers. Therefore the file allows you to open the file straight in Photoshop and edit the image plus use most of the features of the software. However, the main difficulty is that when editing or changing any features, you must open it on its actual software which is Adobe Photoshop.
Also the file is relatively large therefore; it will take up a lot of space on your computer which is in the RAM. JPEG format- JPEG is an acronym for ‘Joint Photographic Experts Group’ format. This format is a raster file document that is a popular file format that has range of compatibility, high quality compatibilities and file size. JPEG format is commonly used with all people; this is because it’s used a lot when downloading images from the internet or when taking pictures with cameras and etc. JPEG images do not take a lot of storage spaces which is an advantage. The disadvantage is that when you take JPEG image from the computer and try expanding it by stretching, then the possibilities are that it could get pixilated.
The quality of this file format is not so good as said before- it could get pixilated when stretched, printed, zoomed in as they are compressed to suit a smaller sized image, therefore not look efficient and unclear to see. * TIF format- TIF is also known as ‘Tag Information File Format’. This format is owned by Adobe and supported by image manipulation applications, by publishing by page by page layout applications, by scanning, faxing, word processing, optical character recognition and other applications. This format is used for traditional print graphics.
If a wrong technique is used, the possibility is that it could cause irreversible reduction in image quality. It is vital to know exactly what effect changing variables of an image has on the final product; this is due to when increasing the resolution. This is mainly because, when increasing the size of the file will also increase and improve the quality that reducing the image resolution of the image will reduce the file size and reduce the quality of the image the same time.
* GIF format- GIF is an acronym that is known as ‘Graphic Interchange Format’ and it’s mainly used on the web e. . websites and applications. GIF is a bitmap image format that makes a reasonably small file size foot print on storage. GIF supports RGB and grayscale colours; therefore, it’s not a preferred format for higher quality images although it is popular choices as it is fast to upload to Webpage’s. This format supports transparency that makes it great for producing simple and small cartooned images. This works well for logos, animations and many more. There is various range of colors- minimum of 256 colours and it can display different types of information at the same time.
The types of people that would use this format are website designers. A disadvantage is that a single TIF format file can take up to 100 megabytes or other storage spaces. The smallest TIFF files are too large to send by email, other applications; most Web browser cannot open TIFF files. All these file formats will result will either take a lot of spaces on the RAM or maybe taken up less spaces. E. g. JPEG formats will take less space compared to other formats, whereas, GIP and PSD will take a massive spaces.
Compression techniques: There are two types of compression techniques and they are named ‘lossy compression’ and ‘lossless compression’. The files can be compressed to make it smaller and each methods affect images in different ways. Therefore, the compression techniques are used to reduce the dark size of the file. Hence if the file size is reduced then there are more storage spaces. Lossy compression happens when the compression turns out in pixels and resolution is lost after compression taken places. This is why the file can be used efficiently and at a lower file size.
This compression usually happens during video conferencing and during freeze frames or when an image is pixilated. This is accepted as high resolution is not needed as long as the user understands the file. Disadvantage of it is that it could give poor quality which could cause miscommunication. Lossless compression is when you compress the file and expect it to be the same as before, so the user may want the output in high resolution; this is used when compressing important files, such as school work, bank information etc. here are some ways of compressing images so they are compressed to your standards, therefore, it can either increase or decrease the file size according to the users liking.
In simple words, lossless from the compressed images can be rebuilt from the compressed images. Whereas, lossy compression is the opposite, so the original image cannot be rebuilt from the compressed images. When we use different types of compression techniques, we could see the changes in the file size as shown above, due to the image of either low quality or high quality.
A JPEG file has a smaller file size compared to GIF file size; this is due to the compression. According to lossless compression, GIF image has higher resolution, this clearly states when looking at the file size Image resolution: Image is resolution is basically the amount of detailed the image contains. Therefore, it can be for digital images, such as vector or bitmap images, film images and other types of images. Image quality and resolution is essentially the amount of points that make up an image is its resolution.
The more the points used to create an image, the more quality and detail of the image will contain. Often larger files indicates an image with better resolution and an image with will small file size indicating a low resolution. Sometimes it’s compulsory to balance file size and resolution for the images intended use, for example, maximum resolution is required if an image is to be scaled up to be used on a billboard, in this situation, the file size is less important. Therefore, when it comes to different file formats, it’s clear that larger the image file is, better the quality of image.
If you have 3. 1 megapixel images on a mobile phone then the quality is average whereas, if you have a camera with 12. 1 megapixels, this would produce a good clarity and be able to see the details in all images and video. The disadvantage is that, the higher the number of pixels in an image, the more space it will need to be stored on either the phone or on a camera. For this, you would need a large memory stick to store the images or if it’s on computer then it will take a lot of hard drive.